[CI Skip] 1.16.1

skip-checks: true

CHANGELOG.md

@@ -1,3 +1,24 @@
+# 1.16.1 May 26, 2020
+
+- Support for Polkadot CC1 types & signed extensions
+- Add support for Babe VRF secondary digests (author extraction)
+- Adjust `Perbill/Permill` `toHuman()` formatting to output percentage
+- Support for latest Substrate types & metadata
+- Update to latest TypeScript, eslint & typescript-eslint
+- `@polkadot/util` 2.11
+
+# 1.15.1 May 23, 2020
+
+- Adjust `keyPrefix()` with DoubleMap args (Thanks to https://github.com/KiChjang)
+- Added `WeightToFeeCoefficient` type (Thanks to https://github.com/danforbes)
+- Spelling fixes for console logs (Thanks to https://github.com/JoshOrndorff)
+- Spelling fixes in cookbook (Thanks to https://github.com/pawelnguyen)
+- Add `transactionVersion` getter in payloads (Thanks to https://github.com/amaurymartiny)
+- Adjust `stakerRewards` derive ordering for improved on-payout refreshes
+- Baseline implementation for derive caching infrastructure
+- Adjust `Multiplier` type to `Fixed128` (as per latest Substrate)
+- Updated to latest Substrate metadata & add new types
+
 # 1.14.1 May 14, 2020
 
 - **Important** `DispatchInfo` changed `paysFee` to an enum, if using an older version use, `DispatchInfo: 'DispatchInfoTo244'`

docs/cookbook/blocks.md

@@ -25,7 +25,7 @@ signedBlock.block.extrinsics.forEach((ex, index) => {
 
 ## How do I extract the block author?
 
-Th block author is encoded inside the consensus logs for the block. To extract, you need to decode the log (which the API does do) and then map the index of the validator to the list of session validators. This extraction is however available on the api derive for new head subscriptions, which returns an extended header with the author populated (assuming that the digest logs are known).
+The block author is encoded inside the consensus logs for the block. To extract, you need to decode the log (which the API does do) and then map the index of the validator to the list of session validators. This extraction is however available on the api derive for new head subscriptions, which returns an extended header with the author populated (assuming that the digest logs are known).
 
 ```js
 // subscribe to all new headers (with extended info)

docs/examples/promise/03_listen_to_balance_change/index.js

@@ -1,6 +1,7 @@
 /* eslint-disable header/header */
 /* eslint-disable @typescript-eslint/require-await */
 /* eslint-disable @typescript-eslint/unbound-method */
+/* eslint-disable @typescript-eslint/no-floating-promises */
 
 // Import the API
 const { ApiPromise } = require('@polkadot/api');

docs/examples/promise/03_listen_to_multiple_balances_change/index.js

@@ -1,6 +1,7 @@
 /* eslint-disable header/header */
 /* eslint-disable @typescript-eslint/require-await */
 /* eslint-disable @typescript-eslint/unbound-method */
+/* eslint-disable @typescript-eslint/no-floating-promises */
 
 // Import the API
 const { ApiPromise } = require('@polkadot/api');

docs/examples/promise/08_system_events/index.js

@@ -1,6 +1,7 @@
 /* eslint-disable header/header */
 /* eslint-disable @typescript-eslint/require-await */
 /* eslint-disable @typescript-eslint/unbound-method */
+/* eslint-disable @typescript-eslint/no-floating-promises */
 
 // Import the API
 const { ApiPromise } = require('@polkadot/api');

docs/examples/promise/09_transfer_events/index.js

@@ -1,6 +1,7 @@
 /* eslint-disable header/header */
 /* eslint-disable @typescript-eslint/require-await */
 /* eslint-disable @typescript-eslint/no-var-requires */
+/* eslint-disable @typescript-eslint/no-floating-promises */
 
 // Import the API & Provider and some utility functions
 const { ApiPromise } = require('@polkadot/api');

docs/examples/promise/10_upgrade_chain/index.js

@@ -1,6 +1,7 @@
 /* eslint-disable header/header */
 /* eslint-disable @typescript-eslint/require-await */
 /* eslint-disable @typescript-eslint/unbound-method */
+/* eslint-disable @typescript-eslint/no-floating-promises */
 
 // Import the API & Provider and some utility functions
 const { ApiPromise, WsProvider } = require('@polkadot/api');

lerna.json

@@ -9,5 +9,5 @@
   "packages": [
     "packages/*"
   ],
-  "version": "1.14.1"
+  "version": "1.16.1"
 }

package.json

@@ -7,7 +7,7 @@
     "packages/*"
   ],
   "resolutions": {
-    "typescript": "^3.8.3"
+    "babel-core": "^7.0.0-bridge.0"
   },
   "scripts": {
     "build": "yarn build:interfaces && polkadot-dev-build-ts && (cd packages/typegen && copyfiles scripts/* build)",
@@ -27,11 +27,11 @@
     "@babel/core": "^7.9.6",
     "@babel/register": "^7.9.0",
     "@babel/runtime": "^7.9.6",
-    "@polkadot/dev": "^0.52.19",
-    "@polkadot/ts": "^0.3.21",
+    "@polkadot/dev": "^0.54.1",
+    "@polkadot/ts": "^0.3.23",
     "@polkadot/typegen": "workspace:packages/typegen",
-    "@types/jest": "^25.2.1",
-    "@vuepress/plugin-search": "^1.4.1",
+    "@types/jest": "^25.2.3",
+    "@vuepress/plugin-search": "^1.5.0",
     "copyfiles": "^2.2.0"
   }
 }

packages/api-contract/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@polkadot/api-contract",
-  "version": "1.14.1",
+  "version": "1.16.1",
   "description": "Interfaces for interacting with contracts and contract ABIs",
   "main": "index.js",
   "keywords": [
@@ -27,11 +27,11 @@
   "homepage": "https://github.com/polkadot-js/api/tree/master/packages/api-contract#readme",
   "dependencies": {
     "@babel/runtime": "^7.9.6",
-    "@polkadot/api": "1.14.1",
-    "@polkadot/rpc-core": "1.14.1",
-    "@polkadot/types": "1.14.1",
-    "@polkadot/util": "^2.10.1",
-    "bn.js": "^5.1.1",
+    "@polkadot/api": "1.16.1",
+    "@polkadot/rpc-core": "1.16.1",
+    "@polkadot/types": "1.16.1",
+    "@polkadot/util": "^2.11.1",
+    "bn.js": "^5.1.2",
     "rxjs": "^6.5.5"
   }
 }

packages/api-contract/src/ContractRegistry.ts

@@ -19,7 +19,7 @@ function parseSelector (registry: Registry, fnname: string, input: ContractABIMe
     return registry.createType('u32', hexToU8a(input));
   } else if (typeof input === 'string') {
     try {
-      const array = JSON.parse(input);
+      const array = JSON.parse(input) as unknown[];
 
       assert(array.length === 4, `${fnname}: Invalid selector length`);
 
@@ -108,7 +108,7 @@ export default class ContractRegistry extends MetaRegistry {
 
   public createMessage (name: string, message: Partial<ContractABIMessage> & ContractABIMessageBase): ContractABIFn {
     const args = message.args.map(({ name, type }): ContractABIFnArg => {
-      assert(isObject(type), `Invalid type at index ${type}`);
+      assert(isObject(type), `Invalid type at index ${type.toString()}`);
 
       return {
         name: stringCamelCase(name),
@@ -183,6 +183,7 @@ export default class ContractRegistry extends MetaRegistry {
   public convertMessage ({ args, name, return_type: returnType, ...message }: ContractABIMessagePre): ContractABIMessage {
     return {
       ...message,
+      // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
       args: this.convertArgs(args),
       name: this._stringAt(name),
       returnType: returnType ? this.convertType(returnType) : null
@@ -191,6 +192,7 @@ export default class ContractRegistry extends MetaRegistry {
 
   public convertEvent ({ args }: ContractABIEventPre): ContractABIEvent {
     return {
+      // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
       args: this.convertArgs(args)
     };
   }

packages/api-contract/src/MetaRegistry.ts

@@ -7,11 +7,11 @@ import { MetaRegistryItem, MetaRegistryJson, MetaTypeDefClikeEnum, MetaType, Met
 import { assert } from '@polkadot/util';
 import { displayType, withTypeString } from '@polkadot/types';
 
-const builtinMap: [(id: any) => boolean, MetaTypeInfo][] = [
-  [(id: any): boolean => typeof id === 'string', MetaTypeInfo.BuiltinPlain],
-  [(id: any): boolean => Array.isArray(id), MetaTypeInfo.BuiltinTuple],
-  [(id: any): boolean => !!(id['array.type']), MetaTypeInfo.BuiltinVecFixed],
-  [(id: any): boolean => !!(id['slice.type']), MetaTypeInfo.BuiltinVec]
+const builtinMap: [(id: unknown | unknown[] | { 'array.type': unknown } | { 'slice.type': unknown }) => boolean, MetaTypeInfo][] = [
+  [(id: any) => typeof id === 'string', MetaTypeInfo.BuiltinPlain],
+  [(id: any) => Array.isArray(id), MetaTypeInfo.BuiltinTuple],
+  [(id: any) => !!((id as { 'array.type': unknown })['array.type']), MetaTypeInfo.BuiltinVecFixed],
+  [(id: any) => !!((id as { 'slice.type': unknown })['slice.type']), MetaTypeInfo.BuiltinVec]
 ];
 
 const typeMap: [string, MetaTypeInfo][] = [
@@ -25,8 +25,8 @@ function detectedType ({ def, id }: MetaType): MetaTypeInfo {
   assert(!(def as MetaTypeDefUnion)['union.fields'], 'Invalid union type definition found');
 
   const lookup = def === 'builtin'
-    ? builtinMap.find(([test]): boolean => test(id))
-    : typeMap.find(([test]): boolean => !!(def as any)[test]);
+    ? builtinMap.find(([test]) => test(id))
+    : typeMap.find(([test]) => !!(def as unknown as Record<string, unknown>)[test]);
 
   return lookup
     ? lookup[1]
@@ -59,7 +59,7 @@ class MetadataRegistryLookup {
     }
   }
 
-  protected _itemAt (index: number, variant: MetaRegistryItem): any {
+  protected _itemAt (index: number, variant: MetaRegistryItem): string | MetaType | TypeDef {
     assert(this._hasItemAt(index, variant), `MetaRegistry: Invalid ${variant} index ${index} found in metadata`);
 
     switch (variant) {
@@ -72,24 +72,24 @@ class MetadataRegistryLookup {
     }
   }
 
-  protected _itemsAt (indices: number[], variant: MetaRegistryItem): any[] {
-    return indices.map((index: number): string => this._itemAt(index, variant));
+  protected _itemsAt (indices: number[], variant: MetaRegistryItem): (string | MetaType | TypeDef)[] {
+    return indices.map((index: number) => this._itemAt(index, variant));
   }
 
   protected _stringAt (index: StringIndex): string {
-    return this._itemAt(index, MetaRegistryItem.String);
+    return this._itemAt(index, MetaRegistryItem.String) as string;
   }
 
   public stringsAt (indices: StringIndex[]): string[] {
-    return this._itemsAt(indices, MetaRegistryItem.String);
+    return this._itemsAt(indices, MetaRegistryItem.String) as string[];
   }
 
   public typeAt (index: TypeIndex): MetaType {
-    return this._itemAt(index, MetaRegistryItem.Type);
+    return this._itemAt(index, MetaRegistryItem.Type) as MetaType;
   }
 
   public typesAt (indices: TypeIndex[]): MetaType[] {
-    return this._itemsAt(indices, MetaRegistryItem.Type);
+    return this._itemsAt(indices, MetaRegistryItem.Type) as MetaType[];
   }
 
   public hasTypeDefAt (index: TypeIndex): boolean {
@@ -98,7 +98,7 @@ class MetadataRegistryLookup {
 
   public typeDefAt (index: TypeIndex, extra: Pick<TypeDef, never> = {}): TypeDef {
     return {
-      ...this._itemAt(index, MetaRegistryItem.TypeDef),
+      ...this._itemAt(index, MetaRegistryItem.TypeDef) as TypeDef,
       ...extra
     };
   }
@@ -136,7 +136,7 @@ export default class MetaRegistry extends MetadataRegistryLookup {
     };
   }
 
-  private _typeDefDefFields (metaType: MetaType, typeIndex?: TypeIndex): Pick<TypeDef, never> {
+  private _typeDefDefFields (metaType: MetaType, typeIndex: TypeIndex = -1): Pick<TypeDef, never> {
     let typeDef;
 
     switch (detectedType(metaType)) {
@@ -234,7 +234,7 @@ export default class MetaRegistry extends MetadataRegistryLookup {
     };
   }
 
-  private _typeDefForBuiltinVec (id: MetaTypeIdVec, typeIndex?: TypeIndex): Pick<TypeDef, never> {
+  private _typeDefForBuiltinVec (id: MetaTypeIdVec, typeIndex: TypeIndex = -1): Pick<TypeDef, never> {
     const { 'slice.type': vecTypeIndex } = id;
 
     assert(!typeIndex || vecTypeIndex !== typeIndex, `MetaRegistry: self-referencing registry type at index ${typeIndex}`);
@@ -250,7 +250,7 @@ export default class MetaRegistry extends MetadataRegistryLookup {
     };
   }
 
-  private _typeDefForBuiltinVecFixed (id: MetaTypeIdVecFixed, typeIndex?: TypeIndex): Pick<TypeDef, never> {
+  private _typeDefForBuiltinVecFixed (id: MetaTypeIdVecFixed, typeIndex: TypeIndex = -1): Pick<TypeDef, never> {
     const { 'array.len': vecLength, 'array.type': vecTypeIndex } = id;
 
     assert(!vecLength || vecLength <= 256, 'MetaRegistry: Only support for [Type; <length>], where length <= 256');
@@ -301,7 +301,7 @@ export default class MetaRegistry extends MetadataRegistryLookup {
     };
   }
 
-  public typeDefForOption (id: MetaTypeIdCustom, typeIndex?: TypeIndex): Pick<TypeDef, any> {
+  public typeDefForOption (id: MetaTypeIdCustom, typeIndex: TypeIndex = -1): Pick<TypeDef, any> {
     assert(id['custom.params'] && id['custom.params'][0], `Invalid Option type defined at index ${typeIndex}`);
 
     return {
@@ -310,7 +310,7 @@ export default class MetaRegistry extends MetadataRegistryLookup {
     };
   }
 
-  public typeDefForResult (id: MetaTypeIdCustom, typeIndex?: TypeIndex): Pick<TypeDef, any> {
+  public typeDefForResult (id: MetaTypeIdCustom, typeIndex: TypeIndex = -1): Pick<TypeDef, any> {
     assert(id['custom.params'] && id['custom.params'][0] && id['custom.params'][1], `Invalid Result type defined at index ${typeIndex}`);
 
     return {

packages/api-contract/src/base/Blueprint.ts

@@ -47,6 +47,7 @@ export default class Blueprint<ApiType extends ApiTypes> extends BaseWithTx<ApiT
     assert(!!this.abi.constructors[constructorIndex], `Specified constructor index ${constructorIndex} does not exist`);
 
     return {
+      // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
       signAndSend: this.decorateMethod(
         (account: IKeyringPair | string | AccountId | Address): BlueprintCreateResultSubscription<ApiType> => {
           return this._apiContracts

packages/api-contract/src/base/Code.ts

@@ -19,7 +19,6 @@ import { BaseWithTx } from './util';
 
 type CodePutCodeResultSubscription<ApiType extends ApiTypes> = Observable<CodePutCodeResult<ApiType>>;
 
-// eslint-disable-next-line @typescript-eslint/interface-name-prefix
 export interface CodePutCode<ApiType extends ApiTypes> {
   signAndSend (account: IKeyringPair | string | AccountId | Address): CodePutCodeResultSubscription<ApiType>;
 }
@@ -46,6 +45,7 @@ export default class Code<ApiType extends ApiTypes> extends BaseWithTx<ApiType>
 
   public createBlueprint = (maxGas: number | BN): CodePutCode<ApiType> => {
     return {
+      // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
       signAndSend: this.decorateMethod(
         (account: IKeyringPair | string | AccountId | Address): CodePutCodeResultSubscription<ApiType> =>
           this._apiContracts

packages/api-contract/src/base/Contract.ts

@@ -21,7 +21,6 @@ type ContractCallResultSubscription<ApiType extends ApiTypes, CallType extends C
   ? Observable<ContractCallResult<CallType>>
   : Promise<ObsInnerType<ContractCallResult<CallType>>>;
 
-// eslint-disable-next-line @typescript-eslint/interface-name-prefix
 export interface ContractCall<ApiType extends ApiTypes, CallType extends ContractCallTypes> {
   send (account: IKeyringPair | string | AccountId | Address): ContractCallResultSubscription<ApiType, CallType>;
 }
@@ -45,6 +44,7 @@ export default class Contract<ApiType extends ApiTypes> extends BaseWithTxAndRpc
     const { def, fn } = this.getMessage(message);
 
     return {
+      // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
       send: this.decorateMethod(
         as === 'rpc' && this.hasRpcContractsCall
           ? (account: IKeyringPair | string | AccountId | Address): ContractCallResult<'rpc'> =>

packages/api-contract/src/base/util.ts

@@ -46,7 +46,7 @@ export abstract class Base<ApiType extends ApiTypes> implements ContractBase<Api
       : 0;
     const def = this.abi.abi.contract.messages[index];
 
-    assert(!!def, `Attempted to access a contract message that does not exist: ${typeof nameOrIndex === 'number' ? `index ${nameOrIndex}` : nameOrIndex}`);
+    assert(!!def, `Attempted to access a contract message that does not exist: ${typeof nameOrIndex === 'number' ? `index ${nameOrIndex}` : (nameOrIndex || 'unknown')}`);
 
     const fn = this.abi.messages[def.name] || this.abi.messages[stringCamelCase(def.name)];
 

packages/api-contract/src/types.ts

@@ -23,6 +23,7 @@ export interface ContractBase<ApiType extends ApiTypes> {
 
 export interface ContractABITypePre {
   ty: TypeIndex;
+  // eslint-disable-next-line camelcase
   display_name: StringIndex[];
 }
 
@@ -56,6 +57,7 @@ export interface ContractABIMessageCommon {
 
 export interface ContractABIMessagePre extends ContractABIMessageCommon, ContractABIMessageBasePre {
   name: StringIndex;
+  // eslint-disable-next-line camelcase
   return_type: ContractABITypePre | null;
 }
 
@@ -187,6 +189,7 @@ export interface InterfaceAbi {
 }
 
 export interface InterfaceContractCalls {
+  // eslint-disable-next-line @typescript-eslint/ban-types
   [index: string]: Function;
 }
 

packages/api-derive/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@polkadot/api-derive",
-  "version": "1.14.1",
+  "version": "1.16.1",
   "description": "Common functions used across Polkadot, derived from RPC calls and storage queries.",
   "main": "index.js",
   "keywords": [
@@ -28,17 +28,17 @@
   "homepage": "https://github.com/polkadot-js/api/tree/master/packages/api-derive#readme",
   "dependencies": {
     "@babel/runtime": "^7.9.6",
-    "@polkadot/api": "1.14.1",
-    "@polkadot/rpc-core": "1.14.1",
-    "@polkadot/rpc-provider": "1.14.1",
-    "@polkadot/types": "1.14.1",
-    "@polkadot/util": "^2.10.1",
-    "@polkadot/util-crypto": "^2.10.1",
-    "bn.js": "^5.1.1",
+    "@polkadot/api": "1.16.1",
+    "@polkadot/rpc-core": "1.16.1",
+    "@polkadot/rpc-provider": "1.16.1",
+    "@polkadot/types": "1.16.1",
+    "@polkadot/util": "^2.11.1",
+    "@polkadot/util-crypto": "^2.11.1",
+    "bn.js": "^5.1.2",
     "memoizee": "^0.4.14",
     "rxjs": "^6.5.5"
   },
   "devDependencies": {
-    "@polkadot/keyring": "^2.10.1"
+    "@polkadot/keyring": "^2.11.1"
   }
 }

packages/api-derive/src/accounts/indexToId.ts

@@ -10,6 +10,7 @@ import { map, startWith } from 'rxjs/operators';
 import { ApiInterfaceRx } from '@polkadot/api/types';
 import { ENUMSET_SIZE } from '@polkadot/types/generic/AccountIndex';
 import { Option, Vec } from '@polkadot/types';
+import { isFunction } from '@polkadot/util';
 
 import { memo } from '../util';
 
@@ -51,7 +52,7 @@ function query (api: ApiInterfaceRx, accountIndex: AccountIndex | string): Obser
 export function indexToId (api: ApiInterfaceRx): (accountIndex: AccountIndex | string) => Observable<AccountId | undefined> {
   return memo((accountIndex: AccountIndex | string): Observable<AccountId | undefined> =>
     api.query.indices
-      ? api.query.indices.accounts
+      ? isFunction(api.query.indices.accounts)
         ? query(api, accountIndex)
         : queryEnumSet(api, accountIndex)
       : of(undefined)

packages/api-derive/src/accounts/indexes.ts

@@ -10,6 +10,7 @@ import { Observable, of } from 'rxjs';
 import { map, startWith, switchMap } from 'rxjs/operators';
 import { ENUMSET_SIZE } from '@polkadot/types/generic/AccountIndex';
 import { Vec } from '@polkadot/types';
+import { isFunction } from '@polkadot/util';
 
 import { memo } from '../util';
 
@@ -72,7 +73,7 @@ function queryAccounts (api: ApiInterfaceRx): Observable<AccountIndexes> {
 export function indexes (api: ApiInterfaceRx): () => Observable<AccountIndexes> {
   return memo((): Observable<AccountIndexes> =>
     (api.query.indices
-      ? api.query.indices.accounts
+      ? isFunction(api.query.indices.accounts)
         ? queryAccounts(api)
         : queryEnumSet(api)
       : of({} as AccountIndexes)

packages/api-derive/src/balances/account.ts

@@ -9,6 +9,7 @@ import { DeriveBalancesAccount } from '../types';
 import { Observable, combineLatest, of } from 'rxjs';
 import { map, switchMap } from 'rxjs/operators';
 import { ApiInterfaceRx } from '@polkadot/api/types';
+import { isFunction } from '@polkadot/util';
 
 import { memo } from '../util';
 
@@ -86,9 +87,9 @@ export function account (api: ApiInterfaceRx): (address: AccountIndex | AccountI
         (accountId
           ? combineLatest([
             of(accountId),
-            api.query.system.account
+            isFunction(api.query.system.account)
               ? queryCurrent(api, accountId)
-              : api.query.balances.account
+              : isFunction(api.query.balances.account)
                 ? queryBalancesAccount(api, accountId)
                 : queryBalancesFree(api, accountId)
           ])

packages/api-derive/src/balances/all.ts

@@ -10,7 +10,7 @@ import { Observable, combineLatest, of } from 'rxjs';
 import { map, switchMap } from 'rxjs/operators';
 import { ApiInterfaceRx } from '@polkadot/api/types';
 import { Option, Vec } from '@polkadot/types';
-import { bnMax } from '@polkadot/util';
+import { bnMax, isFunction } from '@polkadot/util';
 
 import { memo } from '../util';
 
@@ -135,7 +135,7 @@ export function all (api: ApiInterfaceRx): (address: AccountIndex | AccountId |
           ? combineLatest([
             of(account),
             api.derive.chain.bestNumber(),
-            api.query.balances.account
+            isFunction(api.query.balances.account)
               ? queryCurrent(api, account.accountId)
               : queryOld(api, account.accountId)
           ])

packages/api-derive/src/balances/fees.ts

@@ -28,12 +28,12 @@ export function fees (api: ApiInterfaceRx): () => Observable<DeriveFees> {
   return memo((): Observable<DeriveFees> =>
     of([
       // deprecated - remove
-      (api.consts.balances?.creationFee as Balance) || api.registry.createType('Balance'),
-      (api.consts.balances?.transferFee as Balance) || api.registry.createType('Balance'),
+      (api.consts.balances?.creationFee as unknown as Balance) || api.registry.createType('Balance'),
+      (api.consts.balances?.transferFee as unknown as Balance) || api.registry.createType('Balance'),
 
       // current
       (api.consts.balances?.existentialDeposit as Balance) || api.registry.createType('Balance'),
-      (api.consts.transactionPayment?.transactionBaseFee as Balance) || api.registry.createType('Balance'),
+      (api.consts.transactionPayment?.transactionBaseFee as unknown as Balance) || api.registry.createType('Balance'),
       (api.consts.transactionPayment?.transactionByteFee as Balance) || api.registry.createType('Balance')
     ]).pipe(
       map(([creationFee, transferFee, existentialDeposit, transactionBaseFee, transactionByteFee]): DeriveFees => ({

packages/api-derive/src/collective/proposals.ts

@@ -9,6 +9,7 @@ import { DeriveCollectiveProposal } from '../types';
 import { Observable, combineLatest, of } from 'rxjs';
 import { map, switchMap } from 'rxjs/operators';
 import { Option } from '@polkadot/types';
+import { isFunction } from '@polkadot/util';
 
 import { memo } from '../util';
 
@@ -30,7 +31,7 @@ function parse ([hashes, proposals, votes]: Result): DeriveCollectiveProposal[]
 
 export function proposals (api: ApiInterfaceRx, section: 'council' | 'technicalCommittee'): () => Observable<DeriveCollectiveProposal[]> {
   return memo((): Observable<DeriveCollectiveProposal[]> =>
-    api.query[section]?.proposals
+    isFunction(api.query[section]?.proposals)
       ? api.query[section].proposals().pipe(
         switchMap((hashes: Hash[]): Observable<Result> =>
           hashes.length

packages/api-derive/src/democracy/dispatchQueue.ts

@@ -10,7 +10,7 @@ import { Observable, combineLatest, of } from 'rxjs';
 import { map, switchMap } from 'rxjs/operators';
 import { ApiInterfaceRx } from '@polkadot/api/types';
 import { Option, Vec, u64 } from '@polkadot/types';
-import { stringToHex } from '@polkadot/util';
+import { isFunction, stringToHex } from '@polkadot/util';
 
 import { memo } from '../util';
 
@@ -96,7 +96,7 @@ function queryScheduler (api: ApiInterfaceRx): Observable<DeriveDispatch[]> {
 
 export function dispatchQueue (api: ApiInterfaceRx): () => Observable<DeriveDispatch[]> {
   return memo((): Observable<DeriveDispatch[]> =>
-    api.query.scheduler?.agenda
+    isFunction(api.query.scheduler?.agenda)
       ? queryScheduler(api)
       : api.query.democracy.dispatchQueue
         ? queryQueue(api)

packages/api-derive/src/democracy/referendumIds.ts

@@ -20,6 +20,7 @@ export function referendumIds (api: ApiInterfaceRx): () => Observable<BN[]> {
       ]).pipe(
         map(([first, total]): BN[] =>
           total.gt(first)
+            // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
             ? [...Array(total.sub(first).toNumber())].map((_, i): BN => first.addn(i))
             : []
         )

packages/api-derive/src/democracy/referendumsInfo.ts

@@ -10,6 +10,7 @@ import BN from 'bn.js';
 import { Observable, of, combineLatest } from 'rxjs';
 import { map, switchMap } from 'rxjs/operators';
 import { Option, Vec } from '@polkadot/types';
+import { isFunction } from '@polkadot/util';
 
 import { memo } from '../util';
 import { calcVotes, getStatus, parseImage } from './util';
@@ -95,7 +96,7 @@ export function _referendumVotes (api: ApiInterfaceRx): (referendum: DeriveRefer
   return memo((referendum: DeriveReferendum): Observable<DeriveReferendumVotes> =>
     combineLatest([
       api.derive.democracy.sqrtElectorate(),
-      api.query.democracy.votingOf
+      isFunction(api.query.democracy.votingOf)
         ? votesCurr(api, referendum.index)
         : votesPrev(api, referendum.index)
     ]).pipe(

packages/api-derive/src/index.spec.ts

@@ -2,6 +2,10 @@
 // This software may be modified and distributed under the terms
 // of the Apache-2.0 license. See the LICENSE file for details.
 
+/* eslint-disable @typescript-eslint/no-unsafe-return */
+/* eslint-disable @typescript-eslint/no-unsafe-call */
+/* eslint-disable @typescript-eslint/restrict-template-expressions */
+
 import { Observable, from } from 'rxjs';
 import ApiRx from '@polkadot/api/rx/Api';
 import MockProvider from '@polkadot/rpc-provider/mock';
@@ -33,7 +37,7 @@ describe('derive', (): void => {
     const api = new ApiRx({ provider: new MockProvider(registry), registry });
 
     beforeAll((done): void => {
-      api.isReady.subscribe((): void => done());
+      api.isReady.subscribe(() => done());
     });
 
     testFunction(api)('accounts', 'idAndIndex', []);

packages/api-derive/src/index.ts

@@ -76,9 +76,11 @@ function injectFunctions<AllSections> (api: ApiInterfaceRx, allSections: AllSect
         .reduce((sectionAcc, _methodName): DeriveSection<typeof section> => {
           const methodName = _methodName as keyof typeof section;
           // Not sure what to do here, casting as any. Though the final types are good
+          // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment,@typescript-eslint/no-unsafe-call
           const method = (section[methodName] as any)(api);
 
           // idem
+          // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment,@typescript-eslint/no-unsafe-member-access
           (sectionAcc as any)[methodName] = method;
 
           return sectionAcc;

packages/api-derive/src/session/indexes.ts

@@ -9,6 +9,7 @@ import { DeriveSessionIndexes } from '../types';
 import { Observable, of } from 'rxjs';
 import { map } from 'rxjs/operators';
 import { Option, u32 } from '@polkadot/types';
+import { isFunction } from '@polkadot/util';
 
 import { memo } from '../util';
 
@@ -79,7 +80,7 @@ export function indexes (api: ApiInterfaceRx): () => Observable<DeriveSessionInd
   return memo((): Observable<DeriveSessionIndexes> =>
     (
       api.query.session && api.query.staking
-        ? api.query.staking.activeEra
+        ? isFunction(api.query.staking.activeEra)
           ? query(api)
           : queryNoActive(api)
         : empty(api)

packages/api-derive/src/session/progress.ts

@@ -9,6 +9,7 @@ import { Observable, combineLatest, of } from 'rxjs';
 import { map, switchMap } from 'rxjs/operators';
 import { ApiInterfaceRx } from '@polkadot/api/types';
 import { Option, u64 } from '@polkadot/types';
+import { isFunction } from '@polkadot/util';
 
 import { memo } from '../util';
 
@@ -77,9 +78,10 @@ function queryBabeNoHistory (api: ApiInterfaceRx): Observable<[DeriveSessionInfo
 export function progress (api: ApiInterfaceRx): () => Observable<DeriveSessionProgress> {
   return memo((): Observable<DeriveSessionProgress> =>
     api.consts.babe
-      ? (api.query.staking.erasStartSessionIndex
-        ? queryBabe(api) // 2.x with Babe
-        : queryBabeNoHistory(api)
+      ? (
+        isFunction(api.query.staking.erasStartSessionIndex)
+          ? queryBabe(api) // 2.x with Babe
+          : queryBabeNoHistory(api)
       ).pipe(
         map(([info, slots]: [DeriveSessionInfo, ResultSlotsFlat]): DeriveSessionProgress =>
           createDerive(api, info, slots)

packages/api-derive/src/staking/erasExposure.ts

@@ -10,10 +10,12 @@ import { Observable, combineLatest, of } from 'rxjs';
 import { map, switchMap } from 'rxjs/operators';
 import { StorageKey } from '@polkadot/types';
 
-import { memo } from '../util';
+import { deriveCache, memo } from '../util';
 
 type KeysAndExposures = [StorageKey, Exposure][];
 
+const CACHE_KEY = 'eraExposure';
+
 function mapStakers (era: EraIndex, stakers: KeysAndExposures): DeriveEraExposure {
   const nominators: DeriveEraNominatorExposure = {};
   const validators: DeriveEraValidatorExposure = {};
@@ -34,26 +36,45 @@ function mapStakers (era: EraIndex, stakers: KeysAndExposures): DeriveEraExposur
   return { era, nominators, validators };
 }
 
+export function _eraExposure (api: ApiInterfaceRx): (era: EraIndex, withActive: boolean) => Observable<DeriveEraExposure> {
+  return memo((era: EraIndex, withActive: boolean): Observable<DeriveEraExposure> => {
+    const cacheKey = `${CACHE_KEY}-${era.toString()}`;
+    const cached = withActive
+      ? undefined
+      : deriveCache.get<DeriveEraExposure>(cacheKey);
+
+    return cached
+      ? of(cached)
+      : api.query.staking.erasStakersClipped.entries(era).pipe(
+        map((stakers): DeriveEraExposure => {
+          const value = mapStakers(era, stakers);
+
+          !withActive && deriveCache.set(cacheKey, value);
+
+          return value;
+        })
+      );
+  });
+}
+
 export function eraExposure (api: ApiInterfaceRx): (era: EraIndex) => Observable<DeriveEraExposure> {
   return memo((era: EraIndex): Observable<DeriveEraExposure> =>
-    api.query.staking.erasStakersClipped.entries(era).pipe(
-      map((stakers) => mapStakers(era, stakers))
-    )
+    api.derive.staking._eraExposure(era, true)
   );
 }
 
-export function _erasExposure (api: ApiInterfaceRx): (eras: EraIndex[]) => Observable<DeriveEraExposure[]> {
-  return memo((eras: EraIndex[]): Observable<DeriveEraExposure[]> =>
+export function _erasExposure (api: ApiInterfaceRx): (eras: EraIndex[], withActive: boolean) => Observable<DeriveEraExposure[]> {
+  return memo((eras: EraIndex[], withActive: boolean): Observable<DeriveEraExposure[]> =>
     eras.length
-      ? combineLatest(eras.map((era) => api.derive.staking.eraExposure(era)))
+      ? combineLatest(eras.map((era) => api.derive.staking._eraExposure(era, withActive)))
       : of([])
   );
 }
 
 export function erasExposure (api: ApiInterfaceRx): (withActive?: boolean) => Observable<DeriveEraExposure[]> {
-  return memo((withActive?: boolean): Observable<DeriveEraExposure[]> =>
+  return memo((withActive = false): Observable<DeriveEraExposure[]> =>
     api.derive.staking.erasHistoric(withActive).pipe(
-      switchMap((eras) => api.derive.staking._erasExposure(eras))
+      switchMap((eras) => api.derive.staking._erasExposure(eras, withActive))
     )
   );
 }

packages/api-derive/src/staking/erasPoints.ts

@@ -9,7 +9,9 @@ import { DeriveEraPoints, DeriveEraValPoints } from '../types';
 import { Observable, of } from 'rxjs';
 import { map, switchMap } from 'rxjs/operators';
 
-import { memo } from '../util';
+import { deriveCache, memo } from '../util';
+
+const CACHE_KEY = 'eraPoints';
 
 function mapValidators ({ individual }: EraRewardPoints): DeriveEraValPoints {
   return [...individual.entries()]
@@ -21,26 +23,48 @@ function mapValidators ({ individual }: EraRewardPoints): DeriveEraValPoints {
     }, {});
 }
 
-export function _erasPoints (api: ApiInterfaceRx): (eras: EraIndex[]) => Observable<DeriveEraPoints[]> {
-  return memo((eras: EraIndex[]): Observable<DeriveEraPoints[]> =>
-    eras.length
-      ? api.query.staking.erasRewardPoints.multi<EraRewardPoints>(eras).pipe(
-        map((points) =>
-          eras.map((era, index): DeriveEraPoints => ({
-            era,
-            eraPoints: points[index].total,
-            validators: mapValidators(points[index])
-          }))
-        )
-      )
-      : of([])
-  );
+function mapPoints (eras: EraIndex[], points: EraRewardPoints[]): DeriveEraPoints[] {
+  return eras.map((era, index): DeriveEraPoints => ({
+    era,
+    eraPoints: points[index].total,
+    validators: mapValidators(points[index])
+  }));
+}
+
+export function _erasPoints (api: ApiInterfaceRx): (eras: EraIndex[], withActive: boolean) => Observable<DeriveEraPoints[]> {
+  return memo((eras: EraIndex[], withActive: boolean): Observable<DeriveEraPoints[]> => {
+    if (!eras.length) {
+      return of([]);
+    }
+
+    const cached: DeriveEraPoints[] = withActive
+      ? []
+      : eras
+        .map((era) => deriveCache.get<DeriveEraPoints>(`${CACHE_KEY}-${era.toString()}`))
+        .filter((value): value is DeriveEraPoints => !!value);
+    const remaining = eras.filter((era) => !cached.some((cached) => era.eq(cached.era)));
+
+    return !remaining.length
+      ? of(cached)
+      : api.query.staking.erasRewardPoints.multi<EraRewardPoints>(remaining).pipe(
+        map((points): DeriveEraPoints[] => {
+          const query = mapPoints(remaining, points);
+
+          !withActive && query.forEach((q) => deriveCache.set(`${CACHE_KEY}-${q.era.toString()}`, q));
+
+          return eras.map((era): DeriveEraPoints =>
+            cached.find((cached) => era.eq(cached.era)) ||
+            query.find((query) => era.eq(query.era)) as DeriveEraPoints
+          );
+        })
+      );
+  });
 }
 
 export function erasPoints (api: ApiInterfaceRx): (withActive?: boolean) => Observable<DeriveEraPoints[]> {
-  return memo((withActive?: boolean): Observable<DeriveEraPoints[]> =>
+  return memo((withActive = false): Observable<DeriveEraPoints[]> =>
     api.derive.staking.erasHistoric(withActive).pipe(
-      switchMap((eras) => api.derive.staking._erasPoints(eras))
+      switchMap((eras) => api.derive.staking._erasPoints(eras, withActive))
     )
   );
 }

packages/api-derive/src/staking/erasPrefs.ts

@@ -10,7 +10,9 @@ import { Observable, combineLatest, of } from 'rxjs';
 import { map, switchMap } from 'rxjs/operators';
 import { StorageKey } from '@polkadot/types';
 
-import { memo } from '../util';
+import { deriveCache, memo } from '../util';
+
+const CACHE_KEY = 'eraPrefs';
 
 function mapPrefs (era: EraIndex, all: [StorageKey, ValidatorPrefs][]): DeriveEraPrefs {
   const validators: DeriveEraValPrefs = {};
@@ -22,26 +24,45 @@ function mapPrefs (era: EraIndex, all: [StorageKey, ValidatorPrefs][]): DeriveEr
   return { era, validators };
 }
 
+export function _eraPrefs (api: ApiInterfaceRx): (era: EraIndex, withActive: boolean) => Observable<DeriveEraPrefs> {
+  return memo((era: EraIndex, withActive: boolean): Observable<DeriveEraPrefs> => {
+    const cacheKey = `${CACHE_KEY}-${era.toString()}`;
+    const cached = withActive
+      ? undefined
+      : deriveCache.get<DeriveEraPrefs>(cacheKey);
+
+    return cached
+      ? of(cached)
+      : api.query.staking.erasValidatorPrefs.entries(era).pipe(
+        map((prefs): DeriveEraPrefs => {
+          const value = mapPrefs(era, prefs);
+
+          !withActive && deriveCache.set(cacheKey, value);
+
+          return value;
+        })
+      );
+  });
+}
+
 export function eraPrefs (api: ApiInterfaceRx): (era: EraIndex) => Observable<DeriveEraPrefs> {
   return memo((era: EraIndex): Observable<DeriveEraPrefs> =>
-    api.query.staking.erasValidatorPrefs.entries(era).pipe(
-      map((prefs) => mapPrefs(era, prefs))
-    )
+    api.derive.staking._eraPrefs(era, true)
   );
 }
 
-export function _erasPrefs (api: ApiInterfaceRx): (eras: EraIndex[]) => Observable<DeriveEraPrefs[]> {
-  return memo((eras: EraIndex[]): Observable<DeriveEraPrefs[]> =>
+export function _erasPrefs (api: ApiInterfaceRx): (eras: EraIndex[], withActive: boolean) => Observable<DeriveEraPrefs[]> {
+  return memo((eras: EraIndex[], withActive: boolean): Observable<DeriveEraPrefs[]> =>
     eras.length
-      ? combineLatest(eras.map((era) => api.derive.staking.eraPrefs(era)))
+      ? combineLatest(eras.map((era) => api.derive.staking._eraPrefs(era, withActive)))
       : of([])
   );
 }
 
 export function erasPrefs (api: ApiInterfaceRx): (withActive?: boolean) => Observable<DeriveEraPrefs[]> {
-  return memo((withActive?: boolean): Observable<DeriveEraPrefs[]> =>
+  return memo((withActive = false): Observable<DeriveEraPrefs[]> =>
     api.derive.staking.erasHistoric(withActive).pipe(
-      switchMap((eras) => api.derive.staking._erasPrefs(eras))
+      switchMap((eras) => api.derive.staking._erasPrefs(eras, withActive))
     )
   );
 }

packages/api-derive/src/staking/erasRewards.ts

@@ -10,25 +10,53 @@ import { Observable, of } from 'rxjs';
 import { map, switchMap } from 'rxjs/operators';
 import { Option } from '@polkadot/types';
 
-import { memo } from '../util';
+import { deriveCache, memo } from '../util';
 
-export function _erasRewards (api: ApiInterfaceRx): (eras: EraIndex[]) => Observable<DeriveEraRewards[]> {
-  return memo((eras: EraIndex[]): Observable<DeriveEraRewards[]> =>
-    eras.length
-      ? api.query.staking.erasValidatorReward.multi<Option<Balance>>(eras).pipe(
-        map((rewards) => eras.map((era, index): DeriveEraRewards => ({
-          era,
-          eraReward: rewards[index].unwrapOrDefault()
-        })))
-      )
-      : of([])
-  );
+const CACHE_KEY = 'eraRewards';
+
+function mapRewards (eras: EraIndex[], optRewards: Option<Balance>[]): DeriveEraRewards[] {
+  return eras.map((era, index): DeriveEraRewards => ({
+    era,
+    eraReward: optRewards[index].unwrapOrDefault()
+  }));
+}
+
+export function _erasRewards (api: ApiInterfaceRx): (eras: EraIndex[], withActive: boolean) => Observable<DeriveEraRewards[]> {
+  return memo((eras: EraIndex[], withActive: boolean): Observable<DeriveEraRewards[]> => {
+    if (!eras.length) {
+      return of([]);
+    }
+
+    const cached: DeriveEraRewards[] = withActive
+      ? []
+      : eras
+        .map((era) => deriveCache.get<DeriveEraRewards>(`${CACHE_KEY}-${era.toString()}`))
+        .filter((value): value is DeriveEraRewards => !!value);
+    const remaining = eras.filter((era) => !cached.some((cached) => era.eq(cached.era)));
+
+    if (!remaining.length) {
+      return of(cached);
+    }
+
+    return api.query.staking.erasValidatorReward.multi<Option<Balance>>(remaining).pipe(
+      map((optRewards) => {
+        const query = mapRewards(remaining, optRewards);
+
+        !withActive && query.forEach((q) => deriveCache.set(`${CACHE_KEY}-${q.era.toString()}`, q));
+
+        return eras.map((era): DeriveEraRewards =>
+          cached.find((cached) => era.eq(cached.era)) ||
+          query.find((query) => era.eq(query.era)) as DeriveEraRewards
+        );
+      })
+    );
+  });
 }
 
 export function erasRewards (api: ApiInterfaceRx): (withActive?: boolean) => Observable<DeriveEraRewards[]> {
-  return memo((withActive?: boolean): Observable<DeriveEraRewards[]> =>
+  return memo((withActive = false): Observable<DeriveEraRewards[]> =>
     api.derive.staking.erasHistoric(withActive).pipe(
-      switchMap((eras) => api.derive.staking._erasRewards(eras))
+      switchMap((eras) => api.derive.staking._erasRewards(eras, withActive))
     )
   );
 }

packages/api-derive/src/staking/erasSlashes.ts

@@ -11,7 +11,9 @@ import { Observable, combineLatest, of } from 'rxjs';
 import { map, switchMap } from 'rxjs/operators';
 import { Option, StorageKey } from '@polkadot/types';
 
-import { memo } from '../util';
+import { deriveCache, memo } from '../util';
+
+const CACHE_KEY = 'eraSlashes';
 
 function mapSlashes (era: EraIndex, noms: [StorageKey, Option<BalanceOf>][], vals: [StorageKey, Option<ITuple<[Perbill, BalanceOf]>>][]): DeriveEraSlashes {
   const nominators: DeriveEraValSlash = {};
@@ -28,31 +30,50 @@ function mapSlashes (era: EraIndex, noms: [StorageKey, Option<BalanceOf>][], val
   return { era, nominators, validators };
 }
 
+export function _eraSlashes (api: ApiInterfaceRx): (era: EraIndex, withActive: boolean) => Observable<DeriveEraSlashes> {
+  return memo((era: EraIndex, withActive: boolean): Observable<DeriveEraSlashes> => {
+    const cacheKey = `${CACHE_KEY}-${era.toString()}`;
+    const cached = withActive
+      ? undefined
+      : deriveCache.get<DeriveEraSlashes>(cacheKey);
+
+    return cached
+      ? of(cached)
+      : combineLatest([
+        api.query.staking.nominatorSlashInEra.entries(era),
+        api.query.staking.validatorSlashInEra.entries(era)
+      ]).pipe(
+        map(([noms, vals]): DeriveEraSlashes => {
+          const value = mapSlashes(era, noms, vals);
+
+          !withActive && deriveCache.set(cacheKey, value);
+
+          return value;
+        })
+      );
+  });
+}
+
 export function eraSlashes (api: ApiInterfaceRx): (era: EraIndex) => Observable<DeriveEraSlashes> {
   return memo((era: EraIndex): Observable<DeriveEraSlashes> =>
-    combineLatest([
-      api.query.staking.nominatorSlashInEra.entries(era),
-      api.query.staking.validatorSlashInEra.entries(era)
-    ]).pipe(
-      map(([noms, vals]) => mapSlashes(era, noms, vals))
-    )
+    api.derive.staking._eraSlashes(era, true)
   );
 }
 
-export function _erasSlashes (api: ApiInterfaceRx): (eras: EraIndex[]) => Observable<DeriveEraSlashes[]> {
-  return memo((eras: EraIndex[]): Observable<DeriveEraSlashes[]> =>
+export function _erasSlashes (api: ApiInterfaceRx): (eras: EraIndex[], withActive: boolean) => Observable<DeriveEraSlashes[]> {
+  return memo((eras: EraIndex[], withActive: boolean): Observable<DeriveEraSlashes[]> =>
     eras.length
       ? combineLatest(
-        eras.map((era) => api.derive.staking.eraSlashes(era))
+        eras.map((era) => api.derive.staking._eraSlashes(era, withActive))
       )
       : of([])
   );
 }
 
 export function erasSlashes (api: ApiInterfaceRx): (withActive?: boolean) => Observable<DeriveEraSlashes[]> {
-  return memo((withActive?: boolean): Observable<DeriveEraSlashes[]> =>
+  return memo((withActive = false): Observable<DeriveEraSlashes[]> =>
     api.derive.staking.erasHistoric(withActive).pipe(
-      switchMap((eras) => api.derive.staking._erasSlashes(eras))
+      switchMap((eras) => api.derive.staking._erasSlashes(eras, withActive))
     )
   );
 }

packages/api-derive/src/staking/ownSlashes.ts

@@ -11,7 +11,7 @@ import { map, switchMap } from 'rxjs/operators';
 import { memo } from '../util';
 
 export function ownSlashes (api: ApiInterfaceRx): (accountId: Uint8Array | string, withActive?: boolean) => Observable<DeriveStakerSlashes[]> {
-  return memo((accountId: Uint8Array | string, withActive?: boolean): Observable<DeriveStakerSlashes[]> => {
+  return memo((accountId: Uint8Array | string, withActive = false): Observable<DeriveStakerSlashes[]> => {
     return api.derive.staking.erasHistoric(withActive).pipe(
       switchMap((eras) =>
         eras.length

packages/api-derive/src/staking/query.ts

@@ -10,6 +10,7 @@ import { DeriveStakingQuery } from '../types';
 import { Observable, combineLatest, of } from 'rxjs';
 import { map, switchMap } from 'rxjs/operators';
 import { Option, Vec } from '@polkadot/types';
+import { isFunction } from '@polkadot/util';
 
 import { memo } from '../util';
 
@@ -87,7 +88,7 @@ export function queryWithQueued (api: ApiInterfaceRx): (accountId: Uint8Array |
     const stashId = api.registry.createType('AccountId', accountId);
 
     return (
-      api.query.staking.erasStakers
+      isFunction(api.query.staking.erasStakers)
         ? retrieveCurr(api, stashId)
         : retrievePrev(api, stashId)
     ).pipe(

packages/api-derive/src/staking/stakerExposure.ts

@@ -11,11 +11,11 @@ import { map, switchMap } from 'rxjs/operators';
 
 import { memo } from '../util';
 
-export function _stakerExposure (api: ApiInterfaceRx): (accountId: Uint8Array | string, eras: EraIndex[]) => Observable<DeriveStakerExposure[]> {
-  return memo((accountId: Uint8Array | string, eras: EraIndex[]): Observable<DeriveStakerExposure[]> => {
+export function _stakerExposure (api: ApiInterfaceRx): (accountId: Uint8Array | string, eras: EraIndex[], withActive: boolean) => Observable<DeriveStakerExposure[]> {
+  return memo((accountId: Uint8Array | string, eras: EraIndex[], withActive: boolean): Observable<DeriveStakerExposure[]> => {
     const stakerId = api.registry.createType('AccountId', accountId).toString();
 
-    return api.derive.staking._erasExposure(eras).pipe(
+    return api.derive.staking._erasExposure(eras, withActive).pipe(
       map((exposures): DeriveStakerExposure[] =>
         exposures.map(({ era, nominators: allNominators, validators: allValidators }): DeriveStakerExposure => {
           const isValidator = !!allValidators[stakerId];
@@ -38,9 +38,9 @@ export function _stakerExposure (api: ApiInterfaceRx): (accountId: Uint8Array |
 }
 
 export function stakerExposure (api: ApiInterfaceRx): (accountId: Uint8Array | string, withActive?: boolean) => Observable<DeriveStakerExposure[]> {
-  return memo((accountId: Uint8Array | string, withActive?: boolean): Observable<DeriveStakerExposure[]> =>
+  return memo((accountId: Uint8Array | string, withActive = false): Observable<DeriveStakerExposure[]> =>
     api.derive.staking.erasHistoric(withActive).pipe(
-      switchMap((eras) => api.derive.staking._stakerExposure(accountId, eras))
+      switchMap((eras) => api.derive.staking._stakerExposure(accountId, eras, withActive))
     )
   );
 }

packages/api-derive/src/staking/stakerPoints.ts

@@ -11,11 +11,11 @@ import { map, switchMap } from 'rxjs/operators';
 
 import { memo } from '../util';
 
-export function _stakerPoints (api: ApiInterfaceRx): (accountId: Uint8Array | string, eras: EraIndex[]) => Observable<DeriveStakerPoints[]> {
-  return memo((accountId: Uint8Array | string, eras: EraIndex[]): Observable<DeriveStakerPoints[]> => {
+export function _stakerPoints (api: ApiInterfaceRx): (accountId: Uint8Array | string, eras: EraIndex[], withActive: boolean) => Observable<DeriveStakerPoints[]> {
+  return memo((accountId: Uint8Array | string, eras: EraIndex[], withActive: boolean): Observable<DeriveStakerPoints[]> => {
     const stakerId = api.registry.createType('AccountId', accountId).toString();
 
-    return api.derive.staking._erasPoints(eras).pipe(
+    return api.derive.staking._erasPoints(eras, withActive).pipe(
       map((points): DeriveStakerPoints[] =>
         points.map(({ era, eraPoints, validators }): DeriveStakerPoints => ({
           era,
@@ -28,9 +28,9 @@ export function _stakerPoints (api: ApiInterfaceRx): (accountId: Uint8Array | st
 }
 
 export function stakerPoints (api: ApiInterfaceRx): (accountId: Uint8Array | string, withActive?: boolean) => Observable<DeriveStakerPoints[]> {
-  return memo((accountId: Uint8Array | string, withActive?: boolean): Observable<DeriveStakerPoints[]> =>
+  return memo((accountId: Uint8Array | string, withActive = false): Observable<DeriveStakerPoints[]> =>
     api.derive.staking.erasHistoric(withActive).pipe(
-      switchMap((eras) => api.derive.staking._stakerPoints(accountId, eras))
+      switchMap((eras) => api.derive.staking._stakerPoints(accountId, eras, withActive))
     )
   );
 }

packages/api-derive/src/staking/stakerRewards.ts

@@ -10,17 +10,18 @@ import BN from 'bn.js';
 import { Observable, combineLatest, of } from 'rxjs';
 import { map, switchMap } from 'rxjs/operators';
 import { Option } from '@polkadot/types';
+import { isFunction } from '@polkadot/util';
 
 import { memo } from '../util';
 
-type Result = [DeriveEraPoints[], DeriveEraPrefs[], DeriveEraRewards[], DeriveStakerExposure[]];
+type ErasResult = [{ unwrapOr: (value: BN) => BN }, DeriveEraPoints[], DeriveEraPrefs[], DeriveEraRewards[]];
 
 const ZERO = new BN(0);
 const MIN_ONE = new BN(-1);
 const COMM_DIV = new BN(1_000_000_000);
 const MAX_ERAS = new BN(1_000_000_000);
 
-function parseRewards (api: ApiInterfaceRx, stashId: AccountId, [erasPoints, erasPrefs, erasRewards, exposures]: Result): DeriveStakerReward[] {
+function parseRewards (api: ApiInterfaceRx, stashId: AccountId, [, erasPoints, erasPrefs, erasRewards]: ErasResult, exposures: DeriveStakerExposure[]): DeriveStakerReward[] {
   return exposures.map(({ era, isEmpty, isValidator, nominating, validators: eraValidators }): DeriveStakerReward => {
     const { eraPoints, validators: allValPoints } = erasPoints.find((p) => p.era.eq(era)) || { eraPoints: ZERO, validators: {} };
     const { eraReward } = erasRewards.find((r) => r.era.eq(era)) || { eraReward: api.registry.createType('Balance') };
@@ -97,28 +98,29 @@ function filterEras (eras: EraIndex[], stakingLedger: StakingLedger): EraIndex[]
   return eras.filter((era) => filterEra(era, stakingLedger));
 }
 
-function filterRewards (api: ApiInterfaceRx, rewards: DeriveStakerReward[], stakingLedger: StakingLedger, withActive?: boolean): Observable<DeriveStakerReward[]> {
+function filterRewards (api: ApiInterfaceRx, eras: EraIndex[], migrateEra: BN, rewards: DeriveStakerReward[], stakingLedger: StakingLedger, withActive: boolean): Observable<DeriveStakerReward[]> {
   if (withActive) {
     return of(rewards);
   }
 
   const validators = uniqValidators(rewards);
 
-  return combineLatest([
-    api.query.staking.migrateEra
-      ? api.query.staking.migrateEra<Option<EraIndex>>()
-      : of({ unwrapOr: () => api.tx.staking.payoutStakers ? ZERO : MAX_ERAS }),
-    api.tx.staking.payoutStakers
+  return (
+    isFunction(api.tx.staking.payoutStakers)
       ? api.derive.staking.queryMulti(validators)
       : of([])
-  ]).pipe(
-    map(([optMigrate, queryValidators]): DeriveStakerReward[] => {
-      const migrateEra: BN = optMigrate.unwrapOr(ZERO);
+  ).pipe(
+    map((queryValidators): DeriveStakerReward[] => {
+      const filter = withActive
+        ? eras
+        : filterEras(eras, stakingLedger);
 
       return rewards
         .filter(({ isEmpty }) => !isEmpty)
         .filter((reward): boolean => {
-          if (reward.era.lt(migrateEra)) {
+          if (!filter.some((filter) => reward.era.eq(filter))) {
+            return false;
+          } else if (reward.era.lt(migrateEra)) {
             // we filter again here, the actual ledger may have changed, e.g. something has been claimed
             return filterEra(reward.era, stakingLedger);
           }
@@ -154,35 +156,41 @@ function filterRewards (api: ApiInterfaceRx, rewards: DeriveStakerReward[], stak
   );
 }
 
-export function _stakerRewards (api: ApiInterfaceRx): (accountId: Uint8Array | string, eras: EraIndex[], withActive?: boolean) => Observable<DeriveStakerReward[]> {
-  return memo((accountId: Uint8Array | string, _eras: EraIndex[], withActive?: boolean): Observable<DeriveStakerReward[]> =>
-    api.derive.staking.query(accountId).pipe(
-      switchMap(({ stakingLedger, stashId }): Observable<DeriveStakerReward[]> => {
+export function _stakerRewardsEras (api: ApiInterfaceRx): (eras: EraIndex[], withActive: boolean) => Observable<ErasResult> {
+  return memo((eras: EraIndex[], withActive: boolean): Observable<ErasResult> =>
+    combineLatest([
+      isFunction(api.query.staking.migrateEra)
+        ? api.query.staking.migrateEra<Option<EraIndex>>()
+        : of({ unwrapOr: () => isFunction(api.tx.staking.payoutStakers) ? ZERO : MAX_ERAS }),
+      api.derive.staking._erasPoints(eras, withActive),
+      api.derive.staking._erasPrefs(eras, withActive),
+      api.derive.staking._erasRewards(eras, withActive)
+    ])
+  );
+}
+
+export function _stakerRewards (api: ApiInterfaceRx): (accountId: Uint8Array | string, eras: EraIndex[], withActive: boolean) => Observable<DeriveStakerReward[]> {
+  return memo((accountId: Uint8Array | string, eras: EraIndex[], withActive: boolean): Observable<DeriveStakerReward[]> =>
+    combineLatest([
+      api.derive.staking.query(accountId),
+      api.derive.staking._stakerExposure(accountId, eras, withActive),
+      api.derive.staking._stakerRewardsEras(eras, withActive)
+    ]).pipe(
+      switchMap(([{ stakingLedger, stashId }, exposures, erasResult]): Observable<DeriveStakerReward[]> => {
+        const migrateEra: BN = erasResult[0].unwrapOr(ZERO);
+
         if (!stashId || !stakingLedger) {
           return of([]);
         }
 
-        const eras = withActive
-          ? _eras
-          : filterEras(_eras, stakingLedger);
-
-        return combineLatest([
-          api.derive.staking._erasPoints(eras),
-          api.derive.staking._erasPrefs(eras),
-          api.derive.staking._erasRewards(eras),
-          api.derive.staking._stakerExposure(stashId, eras)
-        ]).pipe(
-          switchMap((result): Observable<DeriveStakerReward[]> =>
-            filterRewards(api, parseRewards(api, stashId, result), stakingLedger, withActive)
-          )
-        );
+        return filterRewards(api, eras, migrateEra, parseRewards(api, stashId, erasResult, exposures), stakingLedger, withActive);
       })
     )
   );
 }
 
 export function stakerRewards (api: ApiInterfaceRx): (accountId: Uint8Array | string, withActive?: boolean) => Observable<DeriveStakerReward[]> {
-  return memo((accountId: Uint8Array | string, withActive?: boolean): Observable<DeriveStakerReward[]> =>
+  return memo((accountId: Uint8Array | string, withActive = false): Observable<DeriveStakerReward[]> =>
     api.derive.staking.erasHistoric(withActive).pipe(
       switchMap((eras) => api.derive.staking._stakerRewards(accountId, eras, withActive))
     )
@@ -190,7 +198,7 @@ export function stakerRewards (api: ApiInterfaceRx): (accountId: Uint8Array | st
 }
 
 export function stakerRewardsMulti (api: ApiInterfaceRx): (accountIds: (Uint8Array | string)[], withActive?: boolean) => Observable<DeriveStakerReward[][]> {
-  return memo((accountIds: (Uint8Array | string)[], withActive?: boolean): Observable<DeriveStakerReward[][]> =>
+  return memo((accountIds: (Uint8Array | string)[], withActive = false): Observable<DeriveStakerReward[][]> =>
     accountIds.length
       ? api.derive.staking.erasHistoric(withActive).pipe(
         switchMap((eras) =>

packages/api-derive/src/staking/stakerSlashes.ts

@@ -11,11 +11,11 @@ import { map, switchMap } from 'rxjs/operators';
 
 import { memo } from '../util';
 
-export function _stakerSlashes (api: ApiInterfaceRx): (accountId: Uint8Array | string, eras: EraIndex[]) => Observable<DeriveStakerSlashes[]> {
-  return memo((accountId: Uint8Array | string, eras: EraIndex[]): Observable<DeriveStakerSlashes[]> => {
+export function _stakerSlashes (api: ApiInterfaceRx): (accountId: Uint8Array | string, eras: EraIndex[], withActive: boolean) => Observable<DeriveStakerSlashes[]> {
+  return memo((accountId: Uint8Array | string, eras: EraIndex[], withActive: boolean): Observable<DeriveStakerSlashes[]> => {
     const stakerId = api.registry.createType('AccountId', accountId).toString();
 
-    return api.derive.staking._erasSlashes(eras).pipe(
+    return api.derive.staking._erasSlashes(eras, withActive).pipe(
       map((slashes): DeriveStakerSlashes[] =>
         slashes.map(({ era, nominators, validators }): DeriveStakerSlashes => ({
           era,
@@ -27,9 +27,9 @@ export function _stakerSlashes (api: ApiInterfaceRx): (accountId: Uint8Array | s
 }
 
 export function stakerSlashes (api: ApiInterfaceRx): (accountId: Uint8Array | string, withActive?: boolean) => Observable<DeriveStakerSlashes[]> {
-  return memo((accountId: Uint8Array | string, withActive?: boolean): Observable<DeriveStakerSlashes[]> =>
+  return memo((accountId: Uint8Array | string, withActive = false): Observable<DeriveStakerSlashes[]> =>
     api.derive.staking.erasHistoric(withActive).pipe(
-      switchMap((eras) => api.derive.staking._stakerSlashes(accountId, eras))
+      switchMap((eras) => api.derive.staking._stakerSlashes(accountId, eras, withActive))
     )
   );
 }

packages/api-derive/src/type/HeaderExtended.ts

@@ -9,7 +9,7 @@ import runtimeTypes from '@polkadot/types/interfaces/runtime/definitions';
 import { Struct } from '@polkadot/types';
 
 // We can ignore the properties, added via Struct.with
-const _Header: Constructor<Header> = Struct.with(runtimeTypes.types.Header as any) as any;
+const _Header = Struct.with(runtimeTypes.types.Header as any) as Constructor<Header>;
 
 /**
  * @name HeaderExtended

packages/api-derive/src/util/cache.ts

@@ -0,0 +1,66 @@
+// Copyright 2017-2020 @polkadot/api-derive authors & contributors
+// This software may be modified and distributed under the terms
+// of the Apache-2.0 license. See the LICENSE file for details.
+
+import { DeriveCache } from './types';
+
+import { deriveNoopCache } from './cacheImpl';
+
+interface CacheValue<T> {
+  v: T;
+  x: number;
+}
+
+const CHACHE_EXPIRY = 7 * (24 * 60) * (60 * 1000);
+
+let deriveCache: DeriveCache;
+
+function wrapCache (keyStart: string, cache: DeriveCache): DeriveCache {
+  return {
+    del: (partial: string): void => cache.del(`${keyStart}${partial}`),
+    forEach: cache.forEach,
+    get: <T = any> (partial: string): T | undefined => {
+      const key = `${keyStart}${partial}`;
+      const cached = cache.get<CacheValue<T>>(key);
+
+      if (cached) {
+        cached.x = Date.now();
+        cache.set(key, cached);
+
+        return cached.v;
+      }
+
+      return undefined;
+    },
+    set: (partial: string, v: unknown): void => {
+      cache.set(`${keyStart}${partial}`, { v, x: Date.now() });
+    }
+  };
+}
+
+function clearCache (cache: DeriveCache): void {
+  // clear all expired values
+  const now = Date.now();
+  const all: any[] = [];
+
+  cache.forEach((key: string, { x }: CacheValue<any>): void => {
+    ((now - x) > CHACHE_EXPIRY) && all.push(key);
+  });
+
+  // don't do delete inside loop, just in-case
+  all.forEach((key) => cache.del(key));
+}
+
+export function setDeriveCache (prefix = '', cache?: DeriveCache): void {
+  deriveCache = cache
+    ? wrapCache(`derive:${prefix}:`, cache)
+    : deriveNoopCache;
+
+  if (cache) {
+    clearCache(cache);
+  }
+}
+
+setDeriveCache();
+
+export { deriveCache };

packages/api-derive/src/util/cacheImpl.ts

@@ -0,0 +1,35 @@
+// Copyright 2017-2020 @polkadot/api-derive authors & contributors
+// This software may be modified and distributed under the terms
+// of the Apache-2.0 license. See the LICENSE file for details.
+
+import { DeriveCache } from './types';
+
+const mapCache = new Map<string, any>();
+
+const deriveMapCache: DeriveCache = {
+  del: (key: string): void => {
+    mapCache.delete(key);
+  },
+  forEach: (cb: (key: string, value: any) => void): void => {
+    const entries = mapCache.entries();
+
+    for (const entry in entries) {
+      cb(entry[0], entry[1]);
+    }
+  },
+  get: <T = any> (key: string): T | undefined => {
+    return mapCache.get(key) as T;
+  },
+  set: (key: string, value: any): void => {
+    mapCache.set(key, value);
+  }
+};
+
+const deriveNoopCache: DeriveCache = {
+  del: (): void => undefined,
+  forEach: () => undefined,
+  get: (): undefined => undefined,
+  set: (_: string, value: unknown): unknown => value
+};
+
+export { deriveMapCache, deriveNoopCache };

packages/api-derive/src/util/index.ts

@@ -5,6 +5,8 @@
 import { drr } from '@polkadot/rpc-core/rxjs';
 
 export * from './approvalFlagsToBools';
+export * from './cache';
+export * from './cacheImpl';
 export * from './memo';
 
 export { drr };

packages/api-derive/src/util/types.ts

@@ -0,0 +1,10 @@
+// Copyright 2017-2020 @polkadot/api-derive authors & contributors
+// This software may be modified and distributed under the terms
+// of the Apache-2.0 license. See the LICENSE file for details.
+
+export interface DeriveCache {
+  del: (key: string) => void;
+  forEach: (cb: (key: string, value: any) => void) => void;
+  get: <T = any> (key: string) => T | undefined;
+  set: (key: string, value: any) => void;
+}

packages/api/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@polkadot/api",
-  "version": "1.14.1",
+  "version": "1.16.1",
   "description": "Promise and RxJS wrappers around the Polkadot JS RPC",
   "main": "index.js",
   "keywords": [
@@ -27,20 +27,20 @@
   "homepage": "https://github.com/polkadot-js/api/tree/master/packages/api#readme",
   "dependencies": {
     "@babel/runtime": "^7.9.6",
-    "@polkadot/api-derive": "1.14.1",
-    "@polkadot/keyring": "^2.10.1",
-    "@polkadot/metadata": "1.14.1",
-    "@polkadot/rpc-core": "1.14.1",
-    "@polkadot/rpc-provider": "1.14.1",
-    "@polkadot/types": "1.14.1",
-    "@polkadot/types-known": "1.14.1",
-    "@polkadot/util": "^2.10.1",
-    "@polkadot/util-crypto": "^2.10.1",
-    "bn.js": "^5.1.1",
-    "eventemitter3": "^4.0.1",
+    "@polkadot/api-derive": "1.16.1",
+    "@polkadot/keyring": "^2.11.1",
+    "@polkadot/metadata": "1.16.1",
+    "@polkadot/rpc-core": "1.16.1",
+    "@polkadot/rpc-provider": "1.16.1",
+    "@polkadot/types": "1.16.1",
+    "@polkadot/types-known": "1.16.1",
+    "@polkadot/util": "^2.11.1",
+    "@polkadot/util-crypto": "^2.11.1",
+    "bn.js": "^5.1.2",
+    "eventemitter3": "^4.0.4",
     "rxjs": "^6.5.5"
   },
   "devDependencies": {
-    "@polkadot/keyring": "^2.10.1"
+    "@polkadot/keyring": "^2.11.1"
   }
 }

packages/api/src/augment/consts.ts

@@ -2,10 +2,12 @@
 /* eslint-disable */
 
 import { Codec } from '@polkadot/types/types';
+import { Vec } from '@polkadot/types/codec';
 import { u32, u64 } from '@polkadot/types/primitive';
 import { Balance, BalanceOf, BlockNumber, LockIdentifier, ModuleId, Moment, Percent, Permill, RuntimeDbWeight, Weight } from '@polkadot/types/interfaces/runtime';
 import { SessionIndex } from '@polkadot/types/interfaces/session';
 import { EraIndex } from '@polkadot/types/interfaces/staking';
+import { WeightToFeeCoefficient } from '@polkadot/types/interfaces/support';
 
 declare module '@polkadot/metadata/Decorated/consts/types' {
   export interface Constants {
@@ -102,6 +104,10 @@ declare module '@polkadot/metadata/Decorated/consts/types' {
        * How often (in blocks) new public referenda are launched.
        **/
       launchPeriod: AugmentedConst<BlockNumber>;
+      /**
+       * The maximum number of votes for an account.
+       **/
+      maxVotes: AugmentedConst<u32>;
       /**
        * The minimum amount to be used as a deposit for a public referendum proposal.
        **/
@@ -253,6 +259,10 @@ declare module '@polkadot/metadata/Decorated/consts/types' {
        * The fee to be paid for making a transaction; the per-byte portion.
        **/
       transactionByteFee: AugmentedConst<BalanceOf>;
+      /**
+       * The polynomial that is applied in order to derive fee from weight.
+       **/
+      weightToFee: AugmentedConst<Vec<WeightToFeeCoefficient>>;
     };
     treasury: {
       [index: string]: AugmentedConst<object & Codec>;

packages/api/src/augment/query.ts

@@ -5,12 +5,12 @@ import { AnyNumber, ITuple, Observable } from '@polkadot/types/types';
 import { Option, U8aFixed, Vec } from '@polkadot/types/codec';
 import { Bytes, Data, bool, u32, u64 } from '@polkadot/types/primitive';
 import { UncleEntryItem } from '@polkadot/types/interfaces/authorship';
-import { BabeAuthorityWeight, MaybeRandomness, Randomness } from '@polkadot/types/interfaces/babe';
+import { BabeAuthorityWeight, MaybeRandomness, NextConfigDescriptor, Randomness } from '@polkadot/types/interfaces/babe';
 import { AccountData, BalanceLock, ReleasesBalances } from '@polkadot/types/interfaces/balances';
 import { ProposalIndex, Votes } from '@polkadot/types/interfaces/collective';
 import { AuthorityId } from '@polkadot/types/interfaces/consensus';
 import { CodeHash, ContractInfo, PrefabWasmModule, Schedule } from '@polkadot/types/interfaces/contracts';
-import { PreimageStatus, PropIndex, Proposal, ProxyState, ReferendumIndex, ReferendumInfo, Voting } from '@polkadot/types/interfaces/democracy';
+import { PreimageStatus, PropIndex, Proposal, ProxyState, ReferendumIndex, ReferendumInfo, ReleasesDemocracy, Voting } from '@polkadot/types/interfaces/democracy';
 import { VoteThreshold } from '@polkadot/types/interfaces/elections';
 import { SetId, StoredPendingChange, StoredState } from '@polkadot/types/interfaces/grandpa';
 import { RegistrarInfo, Registration } from '@polkadot/types/interfaces/identity';
@@ -78,6 +78,10 @@ declare module '@polkadot/api/types/storage' {
        * execution context should always yield zero.
        **/
       lateness: AugmentedQuery<ApiType, () => Observable<BlockNumber>> & QueryableStorageEntry<ApiType>;
+      /**
+       * Next epoch configuration, if changed.
+       **/
+      nextEpochConfig: AugmentedQuery<ApiType, () => Observable<Option<NextConfigDescriptor>>> & QueryableStorageEntry<ApiType>;
       /**
        * Next epoch randomness.
        **/
@@ -107,6 +111,9 @@ declare module '@polkadot/api/types/storage' {
        * epoch.
        **/
       segmentIndex: AugmentedQuery<ApiType, () => Observable<u32>> & QueryableStorageEntry<ApiType>;
+      /**
+       * TWOX-NOTE: `SegmentIndex` is an increasing integer, so this is okay.
+       **/
       underConstruction: AugmentedQuery<ApiType, (arg: u32 | AnyNumber | Uint8Array) => Observable<Vec<Randomness>>> & QueryableStorageEntry<ApiType>;
     };
     balances: {
@@ -148,6 +155,8 @@ declare module '@polkadot/api/types/storage' {
       codeStorage: AugmentedQuery<ApiType, (arg: CodeHash | string | Uint8Array) => Observable<Option<PrefabWasmModule>>> & QueryableStorageEntry<ApiType>;
       /**
        * The code associated with a given account.
+       * 
+       * TWOX-NOTE: SAFE since `AccountId` is a secure hash.
        **/
       contractInfoOf: AugmentedQuery<ApiType, (arg: AccountId | string | Uint8Array) => Observable<Option<ContractInfo>>> & QueryableStorageEntry<ApiType>;
       /**
@@ -200,8 +209,10 @@ declare module '@polkadot/api/types/storage' {
       cancellations: AugmentedQuery<ApiType, (arg: Hash | string | Uint8Array) => Observable<bool>> & QueryableStorageEntry<ApiType>;
       /**
        * Those who have locked a deposit.
+       * 
+       * TWOX-NOTE: Safe, as increasing integer keys are safe.
        **/
-      depositOf: AugmentedQuery<ApiType, (arg: PropIndex | AnyNumber | Uint8Array) => Observable<Option<ITuple<[BalanceOf, Vec<AccountId>]>>>> & QueryableStorageEntry<ApiType>;
+      depositOf: AugmentedQuery<ApiType, (arg: PropIndex | AnyNumber | Uint8Array) => Observable<Option<ITuple<[Vec<AccountId>, BalanceOf]>>>> & QueryableStorageEntry<ApiType>;
       /**
        * True if the last referendum tabled was submitted externally. False if it was a public
        * proposal.
@@ -210,6 +221,8 @@ declare module '@polkadot/api/types/storage' {
       /**
        * Accounts for which there are locks in action which may be removed at some point in the
        * future. The value is the block number at which the lock expires and may be removed.
+       * 
+       * TWOX-NOTE: OK ― `AccountId` is a secure hash.
        **/
       locks: AugmentedQuery<ApiType, (arg: AccountId | string | Uint8Array) => Observable<Option<BlockNumber>>> & QueryableStorageEntry<ApiType>;
       /**
@@ -232,6 +245,8 @@ declare module '@polkadot/api/types/storage' {
       /**
        * Who is able to vote for whom. Value is the fund-holding account, key is the
        * vote-transaction-sending account.
+       * 
+       * TWOX-NOTE: OK ― `AccountId` is a secure hash.
        **/
       proxy: AugmentedQuery<ApiType, (arg: AccountId | string | Uint8Array) => Observable<Option<ProxyState>>> & QueryableStorageEntry<ApiType>;
       /**
@@ -248,11 +263,21 @@ declare module '@polkadot/api/types/storage' {
       referendumCount: AugmentedQuery<ApiType, () => Observable<ReferendumIndex>> & QueryableStorageEntry<ApiType>;
       /**
        * Information concerning any given referendum.
+       * 
+       * TWOX-NOTE: SAFE as indexes are not under an attacker’s control.
        **/
       referendumInfoOf: AugmentedQuery<ApiType, (arg: ReferendumIndex | AnyNumber | Uint8Array) => Observable<Option<ReferendumInfo>>> & QueryableStorageEntry<ApiType>;
+      /**
+       * Storage version of the pallet.
+       * 
+       * New networks start with last version.
+       **/
+      storageVersion: AugmentedQuery<ApiType, () => Observable<Option<ReleasesDemocracy>>> & QueryableStorageEntry<ApiType>;
       /**
        * All votes for a particular voter. We store the balance for the number of votes that we
        * have recorded. The second item is the total amount of delegations, that will be added.
+       * 
+       * TWOX-NOTE: SAFE as `AccountId`s are crypto hashes anyway.
        **/
       votingOf: AugmentedQuery<ApiType, (arg: AccountId | string | Uint8Array) => Observable<Voting>> & QueryableStorageEntry<ApiType>;
     };
@@ -277,6 +302,8 @@ declare module '@polkadot/api/types/storage' {
       runnersUp: AugmentedQuery<ApiType, () => Observable<Vec<ITuple<[AccountId, BalanceOf]>>>> & QueryableStorageEntry<ApiType>;
       /**
        * Votes and locked stake of a particular voter.
+       * 
+       * TWOX-NOTE: SAFE as `AccountId` is a crypto hash
        **/
       voting: AugmentedQuery<ApiType, (arg: AccountId | string | Uint8Array) => Observable<ITuple<[BalanceOf, Vec<AccountId>]>>> & QueryableStorageEntry<ApiType>;
     };
@@ -298,6 +325,8 @@ declare module '@polkadot/api/types/storage' {
       /**
        * A mapping from grandpa set ID to the index of the *most recent* session for which its
        * members were responsible.
+       * 
+       * TWOX-NOTE: `SetId` is not under user control.
        **/
       setIdSession: AugmentedQuery<ApiType, (arg: SetId | AnyNumber | Uint8Array) => Observable<Option<SessionIndex>>> & QueryableStorageEntry<ApiType>;
       /**
@@ -313,6 +342,8 @@ declare module '@polkadot/api/types/storage' {
       [index: string]: QueryableStorageEntry<ApiType>;
       /**
        * Information that is pertinent to identify the entity behind an account.
+       * 
+       * TWOX-NOTE: OK ― `AccountId` is a secure hash.
        **/
       identityOf: AugmentedQuery<ApiType, (arg: AccountId | string | Uint8Array) => Observable<Option<Registration>>> & QueryableStorageEntry<ApiType>;
       /**
@@ -326,6 +357,8 @@ declare module '@polkadot/api/types/storage' {
        * Alternative "sub" identities of this account.
        * 
        * The first item is the deposit, the second is a vector of the accounts.
+       * 
+       * TWOX-NOTE: OK ― `AccountId` is a secure hash.
        **/
       subsOf: AugmentedQuery<ApiType, (arg: AccountId | string | Uint8Array) => Observable<ITuple<[BalanceOf, Vec<AccountId>]>>> & QueryableStorageEntry<ApiType>;
       /**
@@ -753,14 +786,14 @@ declare module '@polkadot/api/types/storage' {
        * Total length (in bytes) for all extrinsics put together, for the current block.
        **/
       allExtrinsicsLen: AugmentedQuery<ApiType, () => Observable<Option<u32>>> & QueryableStorageEntry<ApiType>;
-      /**
-       * Total weight for all extrinsics for the current block.
-       **/
-      allExtrinsicsWeight: AugmentedQuery<ApiType, () => Observable<ExtrinsicsWeight>> & QueryableStorageEntry<ApiType>;
       /**
        * Map of block numbers to block hashes.
        **/
       blockHash: AugmentedQuery<ApiType, (arg: BlockNumber | AnyNumber | Uint8Array) => Observable<Hash>> & QueryableStorageEntry<ApiType>;
+      /**
+       * The current weight for the block.
+       **/
+      blockWeight: AugmentedQuery<ApiType, () => Observable<ExtrinsicsWeight>> & QueryableStorageEntry<ApiType>;
       /**
        * Digest of the current block, also part of the block header.
        **/

packages/api/src/base/Decorate.ts

@@ -15,14 +15,13 @@ import { map, switchMap, take, tap, toArray } from 'rxjs/operators';
 import decorateDerive, { ExactDerive } from '@polkadot/api-derive';
 import { memo } from '@polkadot/api-derive/util';
 import DecoratedMeta from '@polkadot/metadata/Decorated';
-import getHasher from '@polkadot/metadata/Decorated/storage/fromMetadata/getHasher';
 import RpcCore from '@polkadot/rpc-core';
 import { WsProvider } from '@polkadot/rpc-provider';
 import { Metadata, Null, Option, Raw, Text, TypeRegistry, u64 } from '@polkadot/types';
 import Linkage, { LinkageResult } from '@polkadot/types/codec/Linkage';
 import { DEFAULT_VERSION as EXTRINSIC_DEFAULT_VERSION } from '@polkadot/types/extrinsic/constants';
 import StorageKey, { StorageEntry, unwrapStorageType } from '@polkadot/types/primitive/StorageKey';
-import { assert, compactStripLength, isNull, isUndefined, logger, u8aConcat, u8aToHex } from '@polkadot/util';
+import { assert, compactStripLength, logger, u8aToHex } from '@polkadot/util';
 
 import { createSubmittable } from '../submittable';
 import augmentObject from '../util/augmentObject';
@@ -32,7 +31,7 @@ import Events from './Events';
 
 interface MetaDecoration {
   callIndex?: Uint8Array;
-  meta: any;
+  meta: Record<string, unknown>;
   method: string;
   section: string;
   toJSON: () => any;
@@ -247,9 +246,9 @@ export default abstract class Decorate<ApiType extends ApiTypes> extends Events
       )
       // eslint-disable-next-line @typescript-eslint/no-unused-vars
       .forEach(([_, { method, section }]): void => {
-        delete (this._rpc as any)[section][method];
-        delete (this._rpcCore as any)[section][method];
-        delete (this._rx.rpc as any)[section][method];
+        delete (this._rpc as Record<string, Record<string, unknown>>)[section][method];
+        delete (this._rpcCore as unknown as Record<string, Record<string, unknown>>)[section][method];
+        delete (this._rx.rpc as Record<string, Record<string, unknown>>)[section][method];
       });
   }
 
@@ -258,11 +257,12 @@ export default abstract class Decorate<ApiType extends ApiTypes> extends Events
       const sectionName = _sectionName as keyof DecoratedRpc<ApiType, RpcInterface>;
 
       // out and section here are horrors to get right from a typing perspective :(
-      (out as any)[sectionName] = Object.entries(rpc[sectionName]).reduce((section, [methodName, method]): DecoratedRpcSection<ApiType, RpcInterface[typeof sectionName]> => {
+      (out as Record<string, unknown>)[sectionName] = Object.entries(rpc[sectionName]).reduce((section, [methodName, method]): DecoratedRpcSection<ApiType, RpcInterface[typeof sectionName]> => {
         //  skip subscriptions where we have a non-subscribe interface
         if (this.hasSubscriptions || !(methodName.startsWith('subscribe') || methodName.startsWith('unsubscribe'))) {
-          (section as any)[methodName] = decorateMethod(method, { methodName });
-          (section as any)[methodName].raw = decorateMethod(method.raw, { methodName });
+          (section as Record<string, unknown>)[methodName] = decorateMethod(method, { methodName }) as unknown;
+          // eslint-disable-next-line @typescript-eslint/no-unsafe-member-access
+          (section as Record<string, { raw: unknown }>)[methodName].raw = decorateMethod(method.raw, { methodName }) as unknown;
         }
 
         return section;
@@ -273,10 +273,12 @@ export default abstract class Decorate<ApiType extends ApiTypes> extends Events
   }
 
   protected _decorateMulti<ApiType extends ApiTypes> (decorateMethod: DecorateMethod<ApiType>): QueryableStorageMulti<ApiType> {
+    // eslint-disable-next-line @typescript-eslint/no-unsafe-return
     return decorateMethod((calls: QueryableStorageMultiArg<ApiType>[]): Observable<Codec[]> =>
       this._rpcCore.state.subscribeStorage(
         calls.map((arg: QueryableStorageMultiArg<ApiType>): [QueryableStorageEntry<ApiType>, ...Arg[]] =>
           // the input is a QueryableStorageEntry, convert to StorageEntry
+          // eslint-disable-next-line @typescript-eslint/no-unsafe-return
           Array.isArray(arg)
             ? [arg[0].creator, ...arg.slice(1)]
             : [arg.creator] as any)));
@@ -300,7 +302,8 @@ export default abstract class Decorate<ApiType extends ApiTypes> extends Events
     const decorated = (...params: Arg[]): SubmittableExtrinsic<ApiType> =>
       creator(method(...params));
 
-    return this._decorateFunctionMeta(method, decorated as any) as SubmittableExtrinsicFunction<ApiType>;
+    // eslint-disable-next-line @typescript-eslint/no-unsafe-return
+    return this._decorateFunctionMeta(method as any, decorated as any) as unknown as SubmittableExtrinsicFunction<ApiType>;
   }
 
   protected _decorateStorage<ApiType extends ApiTypes> (storage: Storage, decorateMethod: DecorateMethod<ApiType>): QueryableStorage<ApiType> {
@@ -320,6 +323,7 @@ export default abstract class Decorate<ApiType extends ApiTypes> extends Events
     const getArgs = (...args: any[]): any[] => extractStorageArgs(creator, args);
 
     // FIXME We probably want to be able to query the full list with non-subs as well
+    // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
     const decorated = this.hasSubscriptions && creator.iterKey && creator.meta.type.isMap && creator.meta.type.asMap.linked.isTrue
       ? this._decorateStorageLinked(creator, decorateMethod)
       : decorateMethod((...args: any[]): Observable<Codec> => (
@@ -333,32 +337,41 @@ export default abstract class Decorate<ApiType extends ApiTypes> extends Events
           : this._rpcCore.state.getStorage(getArgs(...args))
       ), { methodName: creator.method });
 
+    // eslint-disable-next-line @typescript-eslint/no-unsafe-member-access
     decorated.creator = creator;
 
+    // eslint-disable-next-line @typescript-eslint/no-unsafe-member-access,@typescript-eslint/no-unsafe-assignment
     decorated.at = decorateMethod((hash: Hash, arg1?: Arg, arg2?: Arg): Observable<Codec> =>
       this._rpcCore.state.getStorage(getArgs(arg1, arg2), hash));
 
+    // eslint-disable-next-line @typescript-eslint/no-unsafe-member-access,@typescript-eslint/no-unsafe-assignment
     decorated.hash = decorateMethod((arg1?: Arg, arg2?: Arg): Observable<Hash> =>
       this._rpcCore.state.getStorageHash(getArgs(arg1, arg2)));
 
+    // eslint-disable-next-line @typescript-eslint/no-unsafe-member-access
     decorated.key = (arg1?: Arg, arg2?: Arg): string =>
       u8aToHex(compactStripLength(creator(creator.meta.type.isDoubleMap ? [arg1, arg2] : arg1))[1]);
 
-    decorated.keyPrefix = (): string =>
-      u8aToHex(creator.keyPrefix);
+    // eslint-disable-next-line @typescript-eslint/no-unsafe-member-access
+    decorated.keyPrefix = (key1?: Arg): string =>
+      u8aToHex(creator.keyPrefix(key1));
 
+    // eslint-disable-next-line @typescript-eslint/no-unsafe-member-access,@typescript-eslint/no-unsafe-assignment
     decorated.range = decorateMethod((range: [Hash, Hash?], arg1?: Arg, arg2?: Arg): Observable<[Hash, Codec][]> =>
       this._decorateStorageRange(decorated, [arg1, arg2], range));
 
+    // eslint-disable-next-line @typescript-eslint/no-unsafe-member-access,@typescript-eslint/no-unsafe-assignment
     decorated.size = decorateMethod((arg1?: Arg, arg2?: Arg): Observable<u64> =>
       this._rpcCore.state.getStorageSize(getArgs(arg1, arg2)));
 
     // .keys() & .entries() only available on map types
     if (creator.iterKey && (creator.meta.type.isMap || creator.meta.type.isDoubleMap)) {
+      // eslint-disable-next-line @typescript-eslint/no-unsafe-member-access,@typescript-eslint/no-unsafe-assignment
       decorated.entries = decorateMethod(
         memo((doubleMapArg?: Arg): Observable<[StorageKey, Codec][]> =>
           this._retrieveMapEntries(creator, doubleMapArg)));
 
+      // eslint-disable-next-line @typescript-eslint/no-unsafe-member-access,@typescript-eslint/no-unsafe-assignment
       decorated.keys = decorateMethod(
         memo((doubleMapArg?: Arg): Observable<StorageKey[]> =>
           this._retrieveMapKeys(creator, doubleMapArg)));
@@ -367,12 +380,13 @@ export default abstract class Decorate<ApiType extends ApiTypes> extends Events
     // only support multi where subs are available
     if (this.hasSubscriptions) {
       // When using double map storage function, user need to pass double map key as an array
+      // eslint-disable-next-line @typescript-eslint/no-unsafe-member-access,@typescript-eslint/no-unsafe-assignment
       decorated.multi = decorateMethod((args: (Arg | Arg[])[]): Observable<Codec[]> =>
         this._rpcCore.state.subscribeStorage(
           args.map((arg: Arg[] | Arg): [StorageEntry, Arg | Arg[]] => [creator, arg])));
     }
 
-    return this._decorateFunctionMeta(creator, decorated) as unknown as QueryableStorageEntry<ApiType>;
+    return this._decorateFunctionMeta(creator as any, decorated) as unknown as QueryableStorageEntry<ApiType>;
   }
 
   private _decorateStorageRange<ApiType extends ApiTypes> (decorated: QueryableStorageEntry<ApiType>, args: [Arg?, Arg?], range: [Hash, Hash?]): Observable<[Hash, Codec][]> {
@@ -389,9 +403,12 @@ export default abstract class Decorate<ApiType extends ApiTypes> extends Events
   }
 
   private _decorateStorageLinked<ApiType extends ApiTypes> (creator: StorageEntry, decorateMethod: DecorateMethod<ApiType>): ReturnType<DecorateMethod<ApiType>> {
-    const result: Map<Codec, ITuple<[Codec, Linkage<Codec>]> | null> = new Map();
+    const result = new Map<Codec, ITuple<[Codec, Linkage<Codec>]> | null>();
     let subject: BehaviorSubject<LinkageResult>;
     let head: Codec | null = null;
+    const iterKey = creator.iterKey;
+
+    assert(iterKey, 'iterKey field is missing');
 
     // retrieve a value based on the key, iterating if it has a next entry. Since
     // entries can be re-linked in the middle of a list, we subscribe here to make
@@ -449,13 +466,15 @@ export default abstract class Decorate<ApiType extends ApiTypes> extends Events
 
     // this handles the case where the head changes effectively, i.e. a new entry
     // appears at the top of the list, the new getNext gets kicked off
+    // eslint-disable-next-line @typescript-eslint/no-unsafe-return
     return decorateMethod((...args: any[]): Observable<LinkageResult | [Codec, Linkage<Codec>]> =>
       args.length
         ? this._rpcCore.state
+          // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
           .subscribeStorage<[[Codec, Linkage<Codec>]]>([[creator, ...args]])
           .pipe(map(([data]): [Codec, Linkage<Codec>] => data))
         : this._rpcCore.state
-          .subscribeStorage<[LinkageResult]>([creator.iterKey])
+          .subscribeStorage<[LinkageResult]>([iterKey()])
           .pipe(switchMap(([key]): Observable<LinkageResult> => getNext(head = key)))
     );
   }
@@ -463,14 +482,7 @@ export default abstract class Decorate<ApiType extends ApiTypes> extends Events
   private _retrieveMapKeys ({ iterKey, meta }: StorageEntry, arg?: Arg): Observable<StorageKey[]> {
     assert(iterKey && (meta.type.isMap || meta.type.isDoubleMap), 'keys can only be retrieved on maps, linked maps and double maps');
 
-    const headKey = this.createType('Raw', u8aConcat(
-      iterKey,
-      meta.type.isDoubleMap && !isUndefined(arg) && !isNull(arg)
-        ? getHasher(meta.type.asDoubleMap.hasher)(
-          this.createType(meta.type.asDoubleMap.key1.toString() as 'Raw', arg).toU8a()
-        )
-        : new Uint8Array([])
-    )).toHex();
+    const headKey = iterKey(arg).toHex();
     const startSubject = new BehaviorSubject<string>(headKey);
 
     return this._rpcCore.state.getKeysPaged

packages/api/src/base/Init.ts

@@ -62,6 +62,7 @@ export default abstract class Init<ApiType extends ApiTypes> extends Decorate<Ap
     // 'connected' event, then the `on('connected')` won't fire anymore. To
     // cater for this case, we call manually `this._onProviderConnect`.
     if (this._rpcCore.provider.isConnected()) {
+      // eslint-disable-next-line @typescript-eslint/no-floating-promises
       this.#onProviderConnect();
     }
   }
@@ -107,7 +108,7 @@ export default abstract class Init<ApiType extends ApiTypes> extends Decorate<Ap
     // manually build a list of all available methods in this RPC, we are
     // going to filter on it to align the cloned RPC without making a call
     Object.keys(source.rpc).forEach((section): void => {
-      Object.keys((source.rpc as any)[section]).forEach((method): void => {
+      Object.keys((source.rpc as Record<string, Record<string, unknown>>)[section]).forEach((method): void => {
         methods.push(`${section}_${method}`);
       });
     });
@@ -130,7 +131,7 @@ export default abstract class Init<ApiType extends ApiTypes> extends Decorate<Ap
           ? of(false)
           : this._rpcCore.state.getMetadata().pipe(
             map((metadata: Metadata): boolean => {
-              l.log(`Runtime version updated to ${version.specVersion}`);
+              l.log(`Runtime version updated to spec=${version.specVersion.toString()}, tx=${version.transactionVersion.toString()}`);
 
               this._runtimeMetadata = metadata;
               this._runtimeVersion = version;
@@ -167,7 +168,7 @@ export default abstract class Init<ApiType extends ApiTypes> extends Decorate<Ap
     await this._filterRpc();
 
     // retrieve metadata, either from chain  or as pass-in via options
-    const metadataKey = `${this._genesisHash}-${runtimeVersion.specVersion}`;
+    const metadataKey = `${this._genesisHash?.toHex() || '0x'}-${runtimeVersion.specVersion.toString()}`;
     const metadata = metadataKey in optMetadata
       ? new Metadata(this.registry, optMetadata[metadataKey])
       : await this._rpcCore.state.getMetadata().toPromise();
@@ -232,7 +233,7 @@ export default abstract class Init<ApiType extends ApiTypes> extends Decorate<Ap
         });
       }, KEEPALIVE_INTERVAL);
     } catch (_error) {
-      const error = new Error(`FATAL: Unable to initialize the API: ${_error.message}`);
+      const error = new Error(`FATAL: Unable to initialize the API: ${(_error as Error).message}`);
 
       l.error(error);
 

packages/api/src/base/index.ts

@@ -29,8 +29,8 @@ interface PkgJson {
 let pkgJson: PkgJson = { name: '@polkadot/api', version: '-' };
 
 import('../package.json')
-  .then((_pkgJson: any): void => {
-    pkgJson = _pkgJson;
+  .then((_pkgJson: unknown): void => {
+    pkgJson = _pkgJson as PkgJson;
   })
   .catch((): void => {
     // ignore

packages/api/src/checkTypes.manual.ts

@@ -87,7 +87,7 @@ async function query (api: ApiPromise, keyring: TestKeyringMap): Promise<void> {
   // check range types
   const entries = await api.query.system.events.range(['0x12345', '0x7890']);
 
-  console.log(`Received ${entries.length} entries, ${entries.map(([hash, events]) => `${hash.toHex()}: ${events.length} events`)}`);
+  console.log(`Received ${entries.length} entries, ${entries.map(([hash, events]) => `${hash.toHex()}: ${events.length} events`).join(', ')}`);
 }
 
 async function rpc (api: ApiPromise): Promise<void> {
@@ -105,6 +105,7 @@ async function rpc (api: ApiPromise): Promise<void> {
   await api.rpc.chain.getBlock.raw('0x123456');
 
   // using raw subs
+  // eslint-disable-next-line @typescript-eslint/no-floating-promises
   api.rpc.chain.subscribeNewHeads.raw((result: Uint8Array): void => {
     console.log(result);
   });
@@ -125,7 +126,7 @@ function types (api: ApiPromise): void {
 
 async function tx (api: ApiPromise, keyring: TestKeyringMap): Promise<void> {
   // transfer, also allows for BigInt inputs here
-  const transfer = api.tx.balances.transfer(keyring.bob.address, 123_456_789n);
+  const transfer = api.tx.balances.transfer(keyring.bob.address, 123456789n);
 
   console.log('transfer as Call', transfer as IMethod);
   console.log('transfer as Extrinsic', transfer as IExtrinsic);
@@ -159,8 +160,9 @@ async function tx (api: ApiPromise, keyring: TestKeyringMap): Promise<void> {
     });
 
   // it allows for query & then using the submittable
-  const second = api.tx.democracy.second(123);
+  const second = api.tx.democracy.second(123, 5);
 
+  // eslint-disable-next-line @typescript-eslint/no-floating-promises
   second.signAndSend('123', (result): void => {
     console.log(result);
   });
@@ -173,12 +175,15 @@ async function main (): Promise<void> {
   const api = await ApiPromise.create();
   const keyring = testKeyring();
 
-  consts(api);
-  derive(api);
-  query(api, keyring);
-  rpc(api);
-  types(api);
-  tx(api, keyring);
+  // eslint-disable-next-line @typescript-eslint/no-floating-promises
+  Promise.all([
+    consts(api),
+    derive(api),
+    query(api, keyring),
+    rpc(api),
+    types(api),
+    tx(api, keyring)
+  ]);
 }
 
 // eslint-disable-next-line @typescript-eslint/unbound-method

packages/api/src/promise/Api.spec.ts

@@ -13,7 +13,7 @@ import { hexToU8a } from '@polkadot/util';
 import { SingleAccountSigner } from '../../test/util';
 import ApiPromise from './Api';
 
-const TRANSFER_SIG = '0xa1d493ab6b74550da434fbc153a739429be68c9d30e59e631fb5d08f348504deefb5577f4824e138741ad102f479109827e8fa9552812a3e5f505a24d10e820f';
+const TRANSFER_SIG = '0x7a10e5ed9a14284eca7bea53f81631981dddda5a3d2dee973b136475947264801465726e4829ae3994d9058df638d959d4e043c7f1924299546790dda1dea20a';
 
 describe('ApiPromise', (): void => {
   const registry = new TypeRegistry();
@@ -39,7 +39,7 @@ describe('ApiPromise', (): void => {
 
     const signer = new SingleAccountSigner(registry, aliceEd);
     const api = await ApiPromise.create({ provider, registry, signer });
-    const transfer = api.tx.balances.transfer(keyring.getPair('0xe659a7a1628cdd93febc04a4e0646ea20e9f5f0ce097d9a05290d4a9e054df4e').address, 321_564_789_876_512_345n);
+    const transfer = api.tx.balances.transfer(keyring.getPair('0xe659a7a1628cdd93febc04a4e0646ea20e9f5f0ce097d9a05290d4a9e054df4e').address, 321564789876512345n);
 
     return { api, transfer: await transfer.signAsync(aliceEd.address, {}) };
   }
@@ -57,8 +57,10 @@ describe('ApiPromise', (): void => {
       const metadata: any = {};
       const key = `${genesisHash}-${specVersion}`;
 
+      // eslint-disable-next-line @typescript-eslint/no-unsafe-member-access
       metadata[key] = rpcData;
 
+      // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
       const api = await ApiPromise.create({ metadata, provider, registry } as ApiOptions);
 
       expect(api.genesisHash).toBeDefined();

packages/api/src/promise/Api.ts

@@ -25,6 +25,7 @@ function extractArgs (args: any[], needsCallback: boolean): [any[], Callback<Cod
   // If the last arg is a function, we pop it, put it into callback.
   // actualArgs will then hold the actual arguments to be passed to `method`
   if (args.length && isFunction(args[args.length - 1])) {
+    // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
     callback = actualArgs.pop();
   }
 
@@ -38,6 +39,7 @@ function extractArgs (args: any[], needsCallback: boolean): [any[], Callback<Cod
 function promiseTracker (resolve: (value: () => void) => void, reject: (value: Error) => void): Tracker {
   let isCompleted = false;
 
+  // eslint-disable-next-line @typescript-eslint/ban-types
   const complete = (fn: Function, value: any): void => {
     if (!isCompleted) {
       isCompleted = true;
@@ -68,24 +70,22 @@ export function decorateMethod<Method extends AnyFunction> (method: Method, opti
     const [actualArgs, callback] = extractArgs(args, !!needsCallback);
 
     if (!callback) {
+      // eslint-disable-next-line @typescript-eslint/no-unsafe-call,@typescript-eslint/no-unsafe-member-access
       return method(...actualArgs).pipe(first()).toPromise() as Promise<ObsInnerType<ReturnType<Method>>>;
     }
 
     return new Promise((resolve, reject): void => {
       const tracker = promiseTracker(resolve, reject);
-      const subscription = method(...actualArgs)
-        .pipe(
-          // if we find an error (invalid params, etc), reject the promise
-          catchError((error): Observable<never> =>
-            tracker.reject(error)
-          ),
-          // upon the first result, resolve with the unsub function
-          tap((): void =>
-            tracker.resolve((): void => subscription.unsubscribe())
-          )
-        )
-        .subscribe(callback);
-    }) as any; // ???
+
+      // eslint-disable-next-line @typescript-eslint/no-unsafe-call,@typescript-eslint/no-unsafe-member-access,@typescript-eslint/no-unsafe-assignment
+      const subscription: { unsubscribe: () => void } = method(...actualArgs).pipe(
+        // if we find an error (invalid params, etc), reject the promise
+        catchError((error): Observable<never> => tracker.reject(error)),
+        // upon the first result, resolve with the unsub function
+        // eslint-disable-next-line @typescript-eslint/no-unsafe-call,@typescript-eslint/no-unsafe-member-access,@typescript-eslint/no-unsafe-return
+        tap(() => tracker.resolve(() => subscription.unsubscribe()))
+      ).subscribe(callback);
+    }) as UnsubscribePromise;
   } as StorageEntryPromiseOverloads;
 }
 

packages/api/src/promise/Combinator.ts

@@ -41,6 +41,7 @@ export default class Combinator<T extends any[] = any[]> {
       this.#fns.push(fn);
 
       // Not quite 100% how to have a variable number at the front here
+      // eslint-disable-next-line @typescript-eslint/no-unsafe-return,@typescript-eslint/ban-types
       return (fn as Function)(...args, this._createCallback(index));
     });
   }
@@ -54,7 +55,7 @@ export default class Combinator<T extends any[] = any[]> {
   }
 
   protected _createCallback (index: number): (value: any) => void {
-    return (value: any): void => {
+    return (value: unknown): void => {
       this.#fired[index] = true;
       this.#results[index] = value;
 
@@ -68,6 +69,7 @@ export default class Combinator<T extends any[] = any[]> {
     }
 
     try {
+      // eslint-disable-next-line @typescript-eslint/no-floating-promises
       this.#callback(this.#results as T);
     } catch (error) {
       // swallow, we don't want the handler to trip us up

packages/api/src/submittable/createClass.ts

@@ -41,6 +41,7 @@ export default function createClass <ApiType extends ApiTypes> ({ api, apiType,
       const [allOptions] = this.#makeSignAndSendOptions(options);
       const address = isKeyringPair(account) ? account.address : account.toString();
 
+      // eslint-disable-next-line @typescript-eslint/no-unsafe-return,@typescript-eslint/no-unsafe-call
       return decorateMethod(
         (): Observable<RuntimeDispatchInfo> =>
           api.derive.tx.signingInfo(address, allOptions.nonce, allOptions.era).pipe(
@@ -70,6 +71,7 @@ export default function createClass <ApiType extends ApiTypes> ({ api, apiType,
     //
     // also supports signing through external signers
     public signAsync (account: AddressOrPair, optionsOrNonce?: Partial<SignerOptions>): SubmittableThis<ApiType, this> {
+      // eslint-disable-next-line @typescript-eslint/no-unsafe-return,@typescript-eslint/no-unsafe-call
       return decorateMethod(
         (): Observable<this> =>
           this.#observeSign(account, optionsOrNonce).pipe(mapTo(this))
@@ -90,6 +92,7 @@ export default function createClass <ApiType extends ApiTypes> ({ api, apiType,
       const [options, statusCb] = this.#makeSignAndSendOptions(optionsOrStatus, optionalStatusCb);
       const isSubscription = api.hasSubscriptions && (this.#ignoreStatusCb || !!statusCb);
 
+      // eslint-disable-next-line @typescript-eslint/no-unsafe-return,@typescript-eslint/no-unsafe-call
       return decorateMethod(
         (): Observable<Codec> => (
           this.#observeSign(account, options).pipe(
@@ -112,6 +115,7 @@ export default function createClass <ApiType extends ApiTypes> ({ api, apiType,
     public send (statusCb?: Callback<ISubmittableResult>): SubmittableResultResult<ApiType> | SubmittableResultSubscription<ApiType> {
       const isSubscription = api.hasSubscriptions && (this.#ignoreStatusCb || !!statusCb);
 
+      // eslint-disable-next-line @typescript-eslint/no-unsafe-return,@typescript-eslint/no-unsafe-call
       return decorateMethod(
         isSubscription
           ? this.#observeSubscribe

packages/api/src/submittable/createSubmittable.ts

@@ -22,6 +22,6 @@ export default function createSubmittable<ApiType extends ApiTypes> (apiType: Ap
       Submittable = createClass<ApiType>({ api, apiType, decorateMethod });
     }
 
-    return new Submittable(api.registry, extrinsic);
+    return new Submittable(api.registry, extrinsic) as SubmittableExtrinsic<ApiType>;
   };
 }

packages/api/src/submittable/types.ts

@@ -3,7 +3,7 @@
 // of the Apache-2.0 license. See the LICENSE file for details.
 
 import { AccountId, Address, Extrinsic, ExtrinsicStatus, EventRecord, Hash, RuntimeDispatchInfo } from '@polkadot/types/interfaces';
-import { AnyNumber, AnyU8a, Callback, Codec, IExtrinsicEra, IKeyringPair, SignatureOptions, Signer, ISubmittableResult } from '@polkadot/types/types';
+import { AnyNumber, AnyU8a, Callback, Codec, IExtrinsicEra, IKeyringPair, Signer, ISubmittableResult } from '@polkadot/types/types';
 import { ApiTypes } from '../types';
 
 import { Observable } from 'rxjs';
@@ -50,9 +50,9 @@ export interface SubmittableExtrinsic<ApiType extends ApiTypes> extends Extrinsi
 
   send(statusCb: Callback<ISubmittableResult>): SubmittableResultSubscription<ApiType>;
 
-  sign(account: IKeyringPair, _options?: Partial<SignatureOptions>): this;
+  sign(account: IKeyringPair, _options?: Partial<SignerOptions>): this;
 
-  signAsync(account: AddressOrPair, _options?: Partial<SignatureOptions>): SubmittableThis<ApiType, this>;
+  signAsync(account: AddressOrPair, _options?: Partial<SignerOptions>): SubmittableThis<ApiType, this>;
 
   signAndSend(account: AddressOrPair, options?: Partial<SignerOptions>): SubmittableResultResult<ApiType>;
 

packages/api/src/types/storage.ts

@@ -40,6 +40,7 @@ export interface StorageEntryBase<ApiType extends ApiTypes, F extends AnyFunctio
 
 export interface StorageEntryDoubleMap<ApiType extends ApiTypes, F extends AnyFunction> extends StorageEntryBase<ApiType, F> {
   entries: <T extends Codec | any = ObsInnerType<ReturnType<F>>>(arg?: Parameters<F>[0]) => PromiseOrObs<ApiType, [StorageKey, T][]>;
+  keyPrefix: (key1?: Parameters<F>[0]) => string;
 }
 
 interface StorageEntryObservableMulti {

packages/api/src/util/augmentObject.spec.ts

@@ -12,6 +12,7 @@ describe('augmentObject', (): void => {
   });
 
   afterEach((): void => {
+    // eslint-disable-next-line @typescript-eslint/no-unsafe-call,@typescript-eslint/no-unsafe-member-access
     spy.mockClear();
   });
 

packages/api/src/util/augmentObject.ts

@@ -74,7 +74,7 @@ function extractMethods (src: Record<string, Record<string, any>>, dst: Record<s
  * already available, but rather just adds new missing ites into the result object.
  * @internal
  */
-export default function augmentObject (prefix: string, src: Record<string, Record<string, any>>, dst: Record<string, Record<string, any>>, fromEmpty = false): Record<string, Record<string, any>> {
+export default function augmentObject (prefix: string, src: Record<string, Record<string, unknown>>, dst: Record<string, Record<string, unknown>>, fromEmpty = false): Record<string, Record<string, any>> {
   if (fromEmpty) {
     Object.keys(dst).forEach((key): void => {
       delete dst[key];
@@ -88,12 +88,12 @@ export default function augmentObject (prefix: string, src: Record<string, Recor
 
   return Object
     .keys(src)
-    .reduce((newSection, sectionName): Record<string, Record<string, any>> => {
+    .reduce((newSection, sectionName): Record<string, Record<string, unknown>> => {
       const section = src[sectionName];
 
       newSection[sectionName] = Object
         .keys(section)
-        .reduce((result, methodName): Record<string, any> => {
+        .reduce((result, methodName): Record<string, unknown> => {
           // TODO When it does match, check the actual details and warn when there are differences
           if (!result[methodName]) {
             result[methodName] = section[methodName];

packages/api/src/util/decorate.ts

@@ -14,17 +14,14 @@ export type DeriveAllSections<ApiType extends ApiTypes, AllSections extends AnyD
 
 // A technically unsafe version of Object.keys(obj) that assumes that
 // obj only has known properties of T
-function keys<T extends object> (obj: T): (keyof T)[] {
-  return Object.keys(obj) as (keyof T)[];
+function keys<T extends Record<string, unknown>> (obj: T): (keyof T)[] {
+  return Object.keys(obj);
 }
 
 /**
  * This is a methods decorator which keeps all type information.
  */
-function decorateMethods<ApiType extends ApiTypes, Section extends Record<string, AnyFunction>> (
-  section: Section,
-  decorateMethod: DecorateMethod<ApiType>
-): DeriveSection<ApiType, Section> {
+function decorateMethods<ApiType extends ApiTypes, Section extends Record<string, AnyFunction>> (section: Section, decorateMethod: DecorateMethod<ApiType>): DeriveSection<ApiType, Section> {
   return keys(section).reduce(
     <MethodName extends keyof Section>(
       acc: DeriveSection<ApiType, Section>,
@@ -32,7 +29,8 @@ function decorateMethods<ApiType extends ApiTypes, Section extends Record<string
     ): DeriveSection<ApiType, Section> => {
       const method = section[methodName];
 
-      acc[methodName] = decorateMethod(method);
+      // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
+      acc[methodName] = decorateMethod(method) as MethodResult<ApiType, Section[MethodName]>;
 
       return acc;
     },

packages/api/src/util/filterEvents.ts

@@ -18,7 +18,7 @@ export default function filterEvents (extHash: H256, { block: { extrinsics, head
   if (index === -1) {
     // only warn on filtering with isInBlock (finalization finalizes after)
     if (status.isInBlock) {
-      l.warn(`block ${header.hash}: Unable to find extrinsic ${myHash} inside ${allHashes}`);
+      l.warn(`block ${header.hash.toHex()}: Unable to find extrinsic ${myHash} inside ${allHashes.join(', ')}`);
     }
 
     return;

packages/api/src/util/validate.spec.ts

@@ -35,8 +35,7 @@ describe('extractStorageArgs', (): void => {
 
   it('validates no-arg plain (failing when there are args)', (): void => {
     expect(
-      (): any[] =>
-        extractStorageArgs(storage.timestamp.now, [123, 456])
+      (): unknown => extractStorageArgs(storage.timestamp.now, [123, 456])
     ).toThrow('timestamp.now() does not take any arguments, 2 found');
   });
 

packages/api/src/util/validate.ts

@@ -35,7 +35,7 @@ function doMap (creator: StorageEntry, args: any[]): [StorageEntry] | [StorageEn
 
 // sets up the arguments in the form of [creator, args] ready to be used in a storage
 // call. Additionally, it verifies that the correct number of arguments have been passed
-export function extractStorageArgs (creator: StorageEntry, _args: any[]): any[] {
+export function extractStorageArgs (creator: StorageEntry, _args: any[]): [StorageEntry, [any, any]] | [StorageEntry] | [StorageEntry, any] {
   const args = _args.filter((arg) => !isUndefined(arg));
 
   if (creator.meta.type.isDoubleMap) {

packages/api/test/util/logEvents.ts

@@ -7,7 +7,7 @@ import { EventRecord } from '@polkadot/types/interfaces';
 import { SubmittableResult } from '../../src';
 
 // log all events for the transfers, calling done() when finalized
-export const logEvents = (done: () => {}): (r: SubmittableResult) => void =>
+export const logEvents = (done: () => Record<string, unknown>): (r: SubmittableResult) => void =>
   ({ events, status }: SubmittableResult): void => {
     console.log('Transaction status:', status.type);
 

packages/metadata/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@polkadot/metadata",
-  "version": "1.14.1",
+  "version": "1.16.1",
   "description": "Helpers to extract information from runtime metadata",
   "main": "index.js",
   "publishConfig": {
@@ -27,13 +27,13 @@
   "homepage": "https://github.com/polkadot-js/api/tree/master/packages/type-metadata#readme",
   "dependencies": {
     "@babel/runtime": "^7.9.6",
-    "@polkadot/types": "1.14.1",
-    "@polkadot/types-known": "1.14.1",
-    "@polkadot/util": "^2.10.1",
-    "@polkadot/util-crypto": "^2.10.1",
-    "bn.js": "^5.1.1"
+    "@polkadot/types": "1.16.1",
+    "@polkadot/types-known": "1.16.1",
+    "@polkadot/util": "^2.11.1",
+    "@polkadot/util-crypto": "^2.11.1",
+    "bn.js": "^5.1.2"
   },
   "devDependencies": {
-    "@polkadot/keyring": "^2.10.1"
+    "@polkadot/keyring": "^2.11.1"
   }
 }

packages/metadata/src/Decorated/storage/fromMetadata/createFunction.spec.ts

@@ -4,7 +4,7 @@
 
 import { Text, TypeRegistry } from '@polkadot/types';
 import { StorageEntry } from '@polkadot/types/primitive/StorageKey';
-import { stringToU8a, u8aConcat, u8aToHex } from '@polkadot/util';
+import { assert, stringToU8a, u8aConcat, u8aToHex } from '@polkadot/util';
 
 import createFunction from './createFunction';
 
@@ -14,6 +14,7 @@ describe('createFunction', (): void => {
   it('should create timestamp.now correctly', (): void => {
     expect(
       createFunction(registry, {
+        // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
         meta: { type: {} } as any,
         method: 'Now',
         prefix: 'Timestamp',
@@ -29,6 +30,7 @@ describe('createFunction', (): void => {
       createFunction(
         registry,
         {
+          // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
           meta: { type: {} } as any,
           method: 'authorityCount',
           prefix: 'Substrate',
@@ -50,6 +52,7 @@ describe('createFunction', (): void => {
       createFunction(
         registry,
         {
+          // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
           meta: { type: {} } as any,
           method: 'authorityCount',
           prefix: 'Substrate',
@@ -74,6 +77,7 @@ describe('createFunction', (): void => {
 
     beforeAll((): void => {
       storageFn = createFunction(registry, {
+        // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
         meta: {
           name: 'metaName',
           type: {
@@ -104,10 +108,22 @@ describe('createFunction', (): void => {
         (): Uint8Array => storageFn(['5DXUeE5N5LtkW97F2PzqYPyqNkxqSWESdGSPTX6AvkUAhwKP'])
       ).toThrow(/requires two arguments/);
     });
+
+    it('accepts an optional parameter for key construction', (): void => {
+      const iterKey = storageFn.iterKey;
+
+      assert(iterKey, 'storageFn.iterKey is undefined');
+
+      const result = iterKey('5DXUeE5N5LtkW97F2PzqYPyqNkxqSWESdGSPTX6AvkUAhwKP');
+
+      expect(u8aToHex(result)).toEqual('0x223416315e3dddca3b5a47fd0ac8e4916482b9ade7bc6657aaca787ba1add3b4c4303117deb55aad9858c8a873273280f78d172b398d5e77e43a2db5e42163e9');
+      expect(u8aToHex(iterKey())).toEqual('0x223416315e3dddca3b5a47fd0ac8e4916482b9ade7bc6657aaca787ba1add3b4');
+    });
   });
 
   it('allows creates double map function with a Null type key', (): void => {
     const storageFn = createFunction(registry, {
+      // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
       meta: {
         type: {
           asDoubleMap: {
@@ -133,6 +149,7 @@ describe('createFunction', (): void => {
 
   it('allows creating of known DoubleMap keys (with Bytes)', (): void => {
     const storageFn = createFunction(registry, {
+      // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
       meta: {
         type: {
           asDoubleMap: {

packages/metadata/src/Decorated/storage/fromMetadata/createFunction.ts

@@ -73,10 +73,7 @@ function createKeyDoubleMap (registry: Registry, itemFn: CreateItemFn, stringKey
   const { meta: { name, type } } = itemFn;
 
   // since we are passing an almost-unknown through, trust, but verify
-  assert(
-    Array.isArray(args) && !isUndefined(args[0]) && !isNull(args[0]) && !isUndefined(args[1]) && !isNull(args[1]),
-    `${name} is a DoubleMap and requires two arguments`
-  );
+  assert(Array.isArray(args) && !isUndefined(args[0]) && !isNull(args[0]) && !isUndefined(args[1]) && !isNull(args[1]), `${(name || 'unknown').toString()} is a DoubleMap and requires two arguments`);
 
   // if this fails, we have bigger issues
   assert(!isUndefined(hasher2), '2 hashing functions should be defined for DoubleMaps');
@@ -110,7 +107,7 @@ function createKey (registry: Registry, itemFn: CreateItemFn, stringKey: string,
   if (type.isMap) {
     const map = type.asMap;
 
-    assert(!isUndefined(arg) && !isNull(arg), `${name} is a Map and requires one argument`);
+    assert(!isUndefined(arg) && !isNull(arg), `${name.toString()} is a Map and requires one argument`);
 
     param = createTypeUnsafe(registry, map.key.toString(), [arg]).toU8a();
   }
@@ -134,7 +131,7 @@ function expandWithMeta ({ meta, method, prefix, section }: CreateItemFn, storag
   // explicitly add the actual method in the toJSON, this gets used to determine caching and without it
   // instances (e.g. collective) will not work since it is only matched on param meta
   storageFn.toJSON = (): any => ({
-    ...(meta.toJSON() as any),
+    ...(meta.toJSON() as Record<string, unknown>),
     storage: { method, prefix, section }
   });
 
@@ -142,7 +139,7 @@ function expandWithMeta ({ meta, method, prefix, section }: CreateItemFn, storag
 }
 
 /** @internal */
-function extendHeadMeta (registry: Registry, { meta: { documentation, name, type }, section }: CreateItemFn, { method }: StorageEntry, iterFn: (arg?: any) => Raw): StorageKey {
+function extendHeadMeta (registry: Registry, { meta: { documentation, name, type }, section }: CreateItemFn, { method }: StorageEntry, iterFn: (arg?: any) => Raw): (arg?: any) => StorageKey {
   const outputType = type.isMap
     ? type.asMap.key.toString()
     : type.asDoubleMap.key1.toString();
@@ -157,7 +154,12 @@ function extendHeadMeta (registry: Registry, { meta: { documentation, name, type
     type: registry.createType('StorageEntryTypeLatest', registry.createType('PlainTypeLatest', type.isMap ? type.asMap.key : type.asDoubleMap.key1), 0)
   });
 
-  return registry.createType('StorageKey', iterFn, { method, section });
+  const prefixKey = registry.createType('StorageKey', iterFn, { method, section });
+
+  return (arg?: any): StorageKey =>
+    !isUndefined(arg) && !isNull(arg)
+      ? registry.createType('StorageKey', iterFn(arg), { method, section })
+      : prefixKey;
 }
 
 // attach the head key hashing for linked maps
@@ -177,8 +179,12 @@ function extendLinkedMap (registry: Registry, itemFn: CreateItemFn, storageFn: S
 // attach the full list hashing for prefixed maps
 /** @internal */
 function extendPrefixedMap (registry: Registry, itemFn: CreateItemFn, storageFn: StorageEntry): StorageEntry {
-  storageFn.iterKey = extendHeadMeta(registry, itemFn, storageFn, (): Raw =>
-    new Raw(registry, createPrefixedKey(itemFn))
+  const { meta: { type } } = itemFn;
+
+  storageFn.iterKey = extendHeadMeta(registry, itemFn, storageFn, (arg?: any): Raw =>
+    type.isDoubleMap && !isUndefined(arg) && !isNull(arg)
+      ? new Raw(registry, u8aConcat(createPrefixedKey(itemFn), getHasher(type.asDoubleMap.hasher)(registry.createType(type.asDoubleMap.key1.toString() as 'Raw', arg).toU8a())))
+      : new Raw(registry, createPrefixedKey(itemFn))
   );
 
   return storageFn;
@@ -219,7 +225,8 @@ export default function createFunction (registry: Registry, itemFn: CreateItemFn
     extendDoubleMap(registry, itemFn, storageFn);
   }
 
-  storageFn.keyPrefix = storageFn.iterKey || compactStripLength(storageFn())[1];
+  storageFn.keyPrefix = (arg?: any): Uint8Array =>
+    (storageFn.iterKey && storageFn.iterKey(arg)) || compactStripLength(storageFn())[1];
 
   return storageFn;
 }

packages/metadata/src/Decorated/storage/fromMetadata/getHasher.ts

@@ -14,11 +14,11 @@ export type HasherFunction = (data: HasherInput) => Uint8Array;
 const DEFAULT_FN = (data: HasherInput): Uint8Array => xxhashAsU8a(data, 128);
 
 const HASHERS: Record<keyof typeof AllHashers, HasherFunction> = {
-  Blake2_128: (data: HasherInput): Uint8Array => // eslint-disable-line @typescript-eslint/camelcase
+  Blake2_128: (data: HasherInput): Uint8Array => // eslint-disable-line camelcase
     blake2AsU8a(data, 128),
-  Blake2_128Concat: (data: HasherInput): Uint8Array => // eslint-disable-line @typescript-eslint/camelcase
+  Blake2_128Concat: (data: HasherInput): Uint8Array => // eslint-disable-line camelcase
     u8aConcat(blake2AsU8a(data, 128), u8aToU8a(data)),
-  Blake2_256: (data: HasherInput): Uint8Array => // eslint-disable-line @typescript-eslint/camelcase
+  Blake2_256: (data: HasherInput): Uint8Array => // eslint-disable-line camelcase
     blake2AsU8a(data, 256),
   Identity: (data: HasherInput): Uint8Array =>
     u8aToU8a(data),

packages/metadata/src/Decorated/storage/fromMetadata/storage.ts

@@ -14,7 +14,7 @@ export default function getStorage (registry: Registry, metaVersion: number): St
     substrate: Object
       .entries(substrate)
       .reduce((storage: Record<string, StorageEntry>, [key, fn]): Record<string, StorageEntry> => {
-        (storage as any)[key] = fn(registry, metaVersion);
+        (storage as Record<string, unknown>)[key] = fn(registry, metaVersion);
 
         return storage;
       }, {})

packages/metadata/src/Metadata/MagicNumber.ts

@@ -2,7 +2,7 @@
 // This software may be modified and distributed under the terms
 // of the Apache-2.0 license. See the LICENSE file for details.
 
-import { Registry } from '@polkadot/types/types';
+import { AnyNumber, Registry } from '@polkadot/types/types';
 
 import { assert } from '@polkadot/util';
 
@@ -11,7 +11,7 @@ import U32 from '@polkadot/types/primitive/U32';
 export const MAGIC_NUMBER = 0x6174656d; // `meta`, reversed for Little Endian encoding
 
 export default class MagicNumber extends U32 {
-  constructor (registry: Registry, value?: any) {
+  constructor (registry: Registry, value?: AnyNumber) {
     super(registry, value);
 
     if (!this.isEmpty) {

packages/metadata/src/Metadata/MetadataVersioned.ts

@@ -33,13 +33,13 @@ type MetaAsX = 'asV0' | 'asV1' | 'asV2' | 'asV3' | 'asV4' | 'asV5' | 'asV6' | 'a
  * The versioned runtime metadata as a decoded structure
  */
 export default class MetadataVersioned extends Struct {
-  readonly #converted: Map<number, MetaMapped> = new Map();
+  readonly #converted = new Map<number, MetaMapped>();
 
-  constructor (registry: Registry, value?: any) {
+  constructor (registry: Registry, value?: unknown) {
     super(registry, {
       magicNumber: MagicNumber,
       metadata: 'MetadataAll'
-    }, value);
+    }, value as Map<unknown, unknown>);
 
     registry.setMetadata(this);
   }

packages/metadata/src/Metadata/util/flattenUniq.ts

@@ -2,9 +2,11 @@
 // This software may be modified and distributed under the terms
 // of the Apache-2.0 license. See the LICENSE file for details.
 
+type Types = string | Types[];
+
 /** @internal */
-export default function flattenUniq (list: any[]): any[] {
-  const flat = list.reduce((result, entry): any[] => {
+export default function flattenUniq (list: Types[]): string[] {
+  const flat = list.reduce((result: string[], entry): string[] => {
     return result.concat(
       Array.isArray(entry)
         ? flattenUniq(entry)
@@ -13,6 +15,6 @@ export default function flattenUniq (list: any[]): any[] {
   }, []);
 
   return [...new Set(flat)]
-    .filter((value: any): any => value)
+    .filter((value: string) => value)
     .sort();
 }

packages/metadata/src/Metadata/util/testUtil.ts

@@ -11,7 +11,7 @@ import getUniqTypes from './getUniqTypes';
 import Metadata from '../Metadata';
 
 /** @internal */
-export function decodeLatestSubstrate<Modules extends Codec> (registry: Registry, version: number, rpcData: string, staticSubstrate: object): void {
+export function decodeLatestSubstrate<Modules extends Codec> (registry: Registry, version: number, rpcData: string, staticSubstrate: Record<string, unknown>): void {
   it('decodes latest substrate properly', (): void => {
     const metadata = new Metadata(registry, rpcData);
 
@@ -49,14 +49,14 @@ export function defaultValues (registry: Registry, rpcData: string, withThrow =
     metadata.asLatest.modules.filter(({ storage }): boolean => storage.isSome).forEach((mod): void => {
       mod.storage.unwrap().items.forEach(({ fallback, name, type }): void => {
         const inner = unwrapStorageType(type);
-        const location = `${mod.name}.${name}: ${inner}`;
+        const location = `${mod.name.toString()}.${name.toString()}: ${inner}`;
 
         it(`creates default types for ${location}`, (): void => {
           expect((): void => {
             try {
               registry.createType(inner, fallback);
             } catch (error) {
-              const message = `${location}:: ${error.message}`;
+              const message = `${location}:: ${(error as Error).message}`;
 
               if (withThrow) {
                 throw new Error(message);

packages/metadata/src/Metadata/util/toCallsOnly.ts

@@ -26,7 +26,7 @@ function mapCalls (registry: Registry, _calls: Option<Vec<FunctionMetadataLatest
         })
       )
       : null
-  );
+  ) as Option<Vec<FunctionMetadataLatest>>;
 }
 
 /** @internal */

packages/metadata/src/Metadata/util/validateTypes.ts

@@ -8,9 +8,11 @@ import { getTypeDef } from '@polkadot/types/create';
 
 import flattenUniq from './flattenUniq';
 
+type Extracted = string | Extracted[];
+
 /** @internal */
-function extractTypes (types: string[]): any[] {
-  return types.map((type): any => {
+function extractTypes (types: string[]): Extracted[] {
+  return types.map((type): Extracted => {
     const decoded = getTypeDef(type);
 
     switch (decoded.info) {
@@ -38,12 +40,10 @@ function extractTypes (types: string[]): any[] {
 
 /** @internal */
 export default function validateTypes (registry: Registry, types: string[], throwError: boolean): void {
-  const missing = flattenUniq(extractTypes(types)).filter((type): boolean =>
-    !registry.hasType(type)
-  );
+  const missing = flattenUniq(extractTypes(types)).filter((type) => !registry.hasType(type));
 
   if (missing.length !== 0) {
-    const message = `Unknown types found, no types for ${missing}`;
+    const message = `Unknown types found, no types for ${missing.join(', ')}`;
 
     if (throwError) {
       throw new Error(message);

packages/rpc-core/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@polkadot/rpc-core",
-  "version": "1.14.1",
+  "version": "1.16.1",
   "description": "A JavaScript wrapper for the Polkadot JsonRPC interface",
   "main": "index.js",
   "keywords": [
@@ -27,14 +27,14 @@
   "homepage": "https://github.com/polkadot-js/api/tree/master/packages/rpc-core#readme",
   "dependencies": {
     "@babel/runtime": "^7.9.6",
-    "@polkadot/metadata": "1.14.1",
-    "@polkadot/rpc-provider": "1.14.1",
-    "@polkadot/types": "1.14.1",
-    "@polkadot/util": "^2.10.1",
+    "@polkadot/metadata": "1.16.1",
+    "@polkadot/rpc-provider": "1.16.1",
+    "@polkadot/types": "1.16.1",
+    "@polkadot/util": "^2.11.1",
     "memoizee": "^0.4.14",
     "rxjs": "^6.5.5"
   },
   "devDependencies": {
-    "@polkadot/keyring": "^2.10.1"
+    "@polkadot/keyring": "^2.11.1"
   }
 }

packages/rpc-core/src/cached.spec.ts

@@ -84,6 +84,7 @@ describe('Cached Observables', (): void => {
 
   it('creates different observables for different methods but same arguments', (): void => {
     // params do not match here
+    // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment,@typescript-eslint/no-unsafe-call,@typescript-eslint/no-unsafe-member-access
     const observable1 = (rpc.chain as any).subscribeNewHeads([123]);
     const observable2 = rpc.state.subscribeStorage([123]);
 

packages/rpc-core/src/formatting.spec.FIXME-ts

@@ -153,7 +153,7 @@ function formattingTests (version: string, decorated: Metadata, encodedValues: [
       }
 
       api.state
-        .subscribeStorage([iterKey])
+        .subscribeStorage([iterKey()])
         .subscribe((value: Codec[]): void => {
           expect(value).toHaveLength(1);
           // console.error('head fallback', value);

packages/rpc-core/src/index.spec.ts

@@ -28,6 +28,7 @@ describe('Api', (): void => {
       }
     });
 
+    // eslint-disable-next-line @typescript-eslint/no-unsafe-member-access
     expect(isFunction((rpc as any).testing.foo)).toBe(true);
     expect(rpc.sections.includes('testing')).toBe(true);
     expect(rpc.mapping.get('testing_foo')).toEqual({

packages/rpc-core/src/index.ts

@@ -63,7 +63,7 @@ function logErrorMessage (method: string, { params, type }: DefinitionRpc, error
 export default class Rpc implements RpcInterface {
   readonly #storageCache = new Map<string, string | null>();
 
-  public readonly mapping: Map<string, DefinitionRpcExt> = new Map();
+  public readonly mapping = new Map<string, DefinitionRpcExt>();
 
   public readonly provider: ProviderInterface;
 
@@ -134,7 +134,7 @@ export default class Rpc implements RpcInterface {
 
     // decorate the sections with base and user methods
     this.sections.forEach((sectionName): void => {
-      (this as any)[sectionName as Section] = {
+      (this as Record<string, unknown>)[sectionName as Section] = {
         ...this._createInterface(sectionName, jsonrpc[sectionName as 'babe'] || {}),
         ...this._createInterface(sectionName, userRpc[sectionName] || {})
       };
@@ -156,7 +156,7 @@ export default class Rpc implements RpcInterface {
         // `<S extends keyof RpcInterface, M extends keyof RpcInterface[S]>`
         // Not doing so, because it makes this class a little bit less readable,
         // and leaving it as-is doesn't harm much
-        (exposed as any)[method] = isSubscription
+        (exposed as Record<string, unknown>)[method] = isSubscription
           ? this._createMethodSubscribe(section, method, def as DefinitionRpcSub)
           : this._createMethodSend(section, method, def);
 
@@ -333,7 +333,7 @@ export default class Rpc implements RpcInterface {
       try {
         return this._formatStorageData(key, result);
       } catch (error) {
-        console.error(`Unable to decode storage ${key.section}.${key.method}:`, error.message);
+        console.error(`Unable to decode storage ${key.section || 'unknown'}.${key.method || 'unknown'}:`, (error as Error).message);
 
         throw error;
       }
@@ -341,10 +341,10 @@ export default class Rpc implements RpcInterface {
       const keys = params[0] as Vec<StorageKey>;
 
       return keys
-        ? this._formatStorageSet(keys, result.changes)
+        ? this._formatStorageSet(keys, (result as { changes: [string, string | null][] }).changes)
         : this.registry.createType('StorageChangeSet', result);
     } else if (rpc.type === 'Vec<StorageChangeSet>') {
-      const mapped = result.map(({ block, changes }: { block: string; changes: [string, string | null][] }): [Hash, Codec[]] => [
+      const mapped = (result as { block: string; changes: [string, string | null][] }[]).map(({ block, changes }): [Hash, Codec[]] => [
         this.registry.createType('Hash', block),
         this._formatStorageSet(params[0] as Vec<StorageKey>, changes)
       ]);
@@ -352,7 +352,7 @@ export default class Rpc implements RpcInterface {
       // we only query at a specific block, not a range - flatten
       return method === 'queryStorageAt'
         ? mapped[0][1]
-        : mapped;
+        : mapped as unknown as Codec[];
     }
 
     return createTypeUnsafe(this.registry, rpc.type, [result]);
@@ -404,7 +404,7 @@ export default class Rpc implements RpcInterface {
       try {
         results.push(this._formatStorageSetEntry(key, changes, withCache));
       } catch (error) {
-        console.error(`Unable to decode storage ${key.section}.${key.method}:`, error.message);
+        console.error(`Unable to decode storage ${key.section || 'unknown'}.${key.method || 'unknown'}:`, (error as Error).message);
 
         throw error;
       }

packages/rpc-core/src/methodSend.spec.ts

@@ -31,7 +31,7 @@ describe('methodSend', (): void => {
     };
 
     provider = {
-      send: jest.fn((method, params): Promise<any> => {
+      send: jest.fn((method, params: any[]): Promise<any> => {
         return Promise.resolve(params[0]);
       })
     };
@@ -41,8 +41,10 @@ describe('methodSend', (): void => {
 
   it('checks for mismatched parameters', (done): void => {
     // private method
+    // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment,@typescript-eslint/no-unsafe-call,@typescript-eslint/no-unsafe-member-access
     const method = (rpc as any)._createMethodSend('test', 'bleh', methods.bleh);
 
+    // eslint-disable-next-line @typescript-eslint/no-unsafe-call,@typescript-eslint/no-unsafe-member-access
     method(1).subscribe(
       (): void => undefined,
       (error: Error): void => {
@@ -53,10 +55,13 @@ describe('methodSend', (): void => {
 
   it('calls the provider with the correct parameters', (done): void => {
     // private method
+    // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment,@typescript-eslint/no-unsafe-call,@typescript-eslint/no-unsafe-member-access
     const method = (rpc as any)._createMethodSend('test', 'blah', methods.blah);
 
     // Args are length-prefixed, because it's a Bytes
+    // eslint-disable-next-line @typescript-eslint/no-unsafe-call,@typescript-eslint/no-unsafe-member-access
     method(new Uint8Array([2 << 2, 0x12, 0x34])).subscribe((): void => {
+      // eslint-disable-next-line @typescript-eslint/no-unsafe-member-access
       expect(provider.send).toHaveBeenCalledWith('test_blah', ['0x1234']);
       done();
     });

packages/rpc-core/src/replay.spec.ts

@@ -18,7 +18,9 @@ describe('replay', (): void => {
 
   it('subscribes via the rpc section', (done): void => {
     // we don't honor types or number of params here
+    // eslint-disable-next-line @typescript-eslint/no-unsafe-member-access
     (rpc.chain as any).getBlockHash = jest.fn((): Observable<number> => of(1));
+    // eslint-disable-next-line @typescript-eslint/no-unsafe-call,@typescript-eslint/no-unsafe-member-access
     (rpc.chain as any).getBlockHash(123, false).subscribe((): void => {
       expect(
         // eslint-disable-next-line @typescript-eslint/unbound-method
@@ -32,6 +34,7 @@ describe('replay', (): void => {
   it('returns the observable value', (done): void => {
     rpc.system.chain().subscribe((value: any): void => {
       if (value) {
+        // eslint-disable-next-line @typescript-eslint/no-unsafe-call,@typescript-eslint/no-unsafe-member-access
         expect(value.toString()).toEqual('mockChain'); // Defined in MockProvider
         done();
       }
@@ -40,9 +43,9 @@ describe('replay', (): void => {
 
   it('replay(1) works as expected', (done): void => {
     const observable = rpc.system.chain();
-    let a: string | undefined;
+    let a: any | undefined;
 
-    observable.subscribe((value: any): void => { a = value; });
+    observable.subscribe((value?: unknown): void => { a = value; });
 
     setTimeout((): void => {
       // Subscribe again to the same observable, it should fire value immediately

packages/rpc-core/src/rxjs/drr.ts

@@ -18,7 +18,7 @@ interface Options {
 
 const l = logger('drr');
 
-const CMP = (a: any, b: any): boolean =>
+const CMP = (a: unknown, b: unknown): boolean =>
   JSON.stringify({ t: a }) === JSON.stringify({ t: b });
 
 const ERR = (error: Error): Observable<never> => {
@@ -40,7 +40,7 @@ export const drr = ({ skipChange = false, skipTimeout = false }: Options = {}):
     catchError(ERR),
     skipChange
       ? tap(NOOP)
-      : distinctUntilChanged(CMP),
+      : distinctUntilChanged<T>(CMP),
     publishReplay(1),
     skipTimeout
       ? refCount()

packages/rpc-provider/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@polkadot/rpc-provider",
-  "version": "1.14.1",
+  "version": "1.16.1",
   "description": "Transport providers for the API",
   "main": "index.js",
   "keywords": [
@@ -27,17 +27,17 @@
   "homepage": "https://github.com/polkadot-js/api/tree/master/packages/rpc-provider#readme",
   "dependencies": {
     "@babel/runtime": "^7.9.6",
-    "@polkadot/metadata": "1.14.1",
-    "@polkadot/types": "1.14.1",
-    "@polkadot/util": "^2.10.1",
-    "@polkadot/util-crypto": "^2.10.1",
-    "bn.js": "^5.1.1",
-    "eventemitter3": "^4.0.1",
+    "@polkadot/metadata": "1.16.1",
+    "@polkadot/types": "1.16.1",
+    "@polkadot/util": "^2.11.1",
+    "@polkadot/util-crypto": "^2.11.1",
+    "bn.js": "^5.1.2",
+    "eventemitter3": "^4.0.4",
     "isomorphic-fetch": "^2.2.1",
     "websocket": "^1.0.31"
   },
   "devDependencies": {
-    "@polkadot/keyring": "^2.10.1",
+    "@polkadot/keyring": "^2.11.1",
     "mock-socket": "^9.0.3",
     "nock": "^12.0.3"
   }

packages/rpc-provider/src/coder/encodeObject.spec.ts

@@ -17,12 +17,12 @@ describe('encodeObject', (): void => {
 
   it('encodes a valid JsonRPC object', (): void => {
     expect(
-      coder.encodeObject('method', 'params')
+      coder.encodeObject('method', ['a', 'b'])
     ).toEqual({
       id: 1,
       jsonrpc: '2.0',
       method: 'method',
-      params: 'params'
+      params: ['a', 'b']
     });
     expect(coder.getId()).toEqual(1);
   });

packages/rpc-provider/src/coder/index.ts

@@ -24,7 +24,7 @@ function formatErrorData (data?: string | number): string {
 export default class RpcCoder {
   #id = 0;
 
-  public decodeResponse (response: JsonRpcResponse): any {
+  public decodeResponse (response: JsonRpcResponse): unknown {
     assert(response, 'Empty response object received');
     assert(response.jsonrpc === '2.0', 'Invalid jsonrpc field in decoded object');
 
@@ -51,7 +51,7 @@ export default class RpcCoder {
     );
   }
 
-  public encodeObject (method: string, params: any | any[]): JsonRpcRequest {
+  public encodeObject (method: string, params: unknown[]): JsonRpcRequest {
     return {
       id: ++this.#id,
       jsonrpc: '2.0',

packages/rpc-provider/src/http/index.spec.ts

@@ -32,13 +32,13 @@ describe('Http', (): void => {
     return http.subscribe('', '', [], (cb): void => {
       expect(cb).toEqual(expect.anything());
     }).catch((error): void => {
-      expect(error.message).toMatch(/does not have subscriptions/);
+      expect((error as Error).message).toMatch(/does not have subscriptions/);
     });
   });
 
   it('does not (yet) support unsubscribe', (): Promise<boolean | void> => {
     return http.unsubscribe('', '', 0).catch((error): void => {
-      expect(error.message).toMatch(/does not have subscriptions/);
+      expect((error as Error).message).toMatch(/does not have subscriptions/);
     });
   });
 });

packages/rpc-provider/src/http/index.ts

@@ -109,6 +109,7 @@ export default class HttpProvider implements ProviderInterface {
 
     assert(response.ok, `[${response.status}]: ${response.statusText}`);
 
+    // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
     const result = await response.json();
 
     return this.#coder.decodeResponse(result);

packages/rpc-provider/src/http/polyfill.spec.ts

@@ -10,14 +10,17 @@ describe('http/polyfill', (): void => {
   let origFetch: any;
 
   beforeEach((): void => {
+    // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
     origFetch = global.fetch;
   });
 
   afterEach((): void => {
+    // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
     global.fetch = origFetch;
   });
 
   it('polyfills with no exceptions (without fetch)', (): void => {
+    // eslint-disable-next-line @typescript-eslint/no-unsafe-member-access
     (global as any).fetch = undefined;
     require('./polyfill');
 
@@ -25,6 +28,7 @@ describe('http/polyfill', (): void => {
   });
 
   it('polyfills with no exceptions (with fetch)', (): void => {
+    // eslint-disable-next-line @typescript-eslint/no-unsafe-member-access
     (global as any).fetch = (): boolean => true;
     require('./polyfill');
 

packages/rpc-provider/src/http/send.spec.ts

@@ -21,6 +21,7 @@ describe('send', (): void => {
   });
 
   it('passes the body through correctly', (): Promise<void> => {
+    // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
     mock = mockHttp([{
       method: 'test_body',
       reply: {
@@ -31,6 +32,7 @@ describe('send', (): void => {
     return http
       .send('test_body', ['param'])
       .then((): void => {
+        // eslint-disable-next-line @typescript-eslint/no-unsafe-member-access
         expect((mock.body as any).test_body).toEqual({
           id: 1,
           jsonrpc: '2.0',
@@ -41,6 +43,7 @@ describe('send', (): void => {
   });
 
   it('throws error when !response.ok', (): Promise<any> => {
+    // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
     mock = mockHttp([{
       code: 500,
       method: 'test_error'
@@ -49,7 +52,7 @@ describe('send', (): void => {
     return http
       .send('test_error', [])
       .catch((error): void => {
-        expect(error.message).toMatch(/\[500\]: Internal Server/);
+        expect((error as Error).message).toMatch(/\[500\]: Internal Server/);
       });
   });
 });

packages/rpc-provider/src/mock/index.ts

@@ -2,7 +2,7 @@
 // This software may be modified and distributed under the terms
 // of the Apache-2.0 license. See the LICENSE file for details.
 
-/* eslint-disable @typescript-eslint/camelcase */
+/* eslint-disable camelcase */
 
 import { Header } from '@polkadot/types/interfaces';
 import { Codec, Registry } from '@polkadot/types/types';
@@ -22,14 +22,15 @@ import { randomAsU8a } from '@polkadot/util-crypto';
 
 const INTERVAL = 1000;
 const SUBSCRIPTIONS: string[] = Array.prototype.concat.apply(
-  [], Object.values(jsonrpc).map((section): string[] =>
+  [],
+  Object.values(jsonrpc).map((section): string[] =>
     Object
       .values(section)
       .filter(({ isSubscription }) => isSubscription)
       .map(({ jsonrpc }) => jsonrpc)
       .concat('chain_subscribeNewHead')
   )
-);
+) as string[];
 
 const keyring = testKeyring({ type: 'ed25519' });
 const l = logger('api-mock');
@@ -50,12 +51,14 @@ export default class Mock implements ProviderInterface {
 
   private prevNumber = new BN(-1);
 
-  private requests: Record<string, (...params: any[]) => any> = {
-    // eslint-disable-next-line @typescript-eslint/no-unused-vars
+  private requests: Record<string, (...params: any[]) => unknown> = {
+    // eslint-disable-next-line @typescript-eslint/no-unused-vars,@typescript-eslint/no-unsafe-member-access
     chain_getBlock: (hash: string): any => this.registry.createType('SignedBlock', rpcSignedBlock.result).toJSON(),
     // eslint-disable-next-line @typescript-eslint/no-unused-vars
     chain_getBlockHash: (blockNumber: number): string => '0x1234',
+    // eslint-disable-next-line @typescript-eslint/no-unsafe-member-access
     chain_getFinalizedHead: () => this.registry.createType('Header', rpcHeader.result).hash,
+    // eslint-disable-next-line @typescript-eslint/no-unsafe-member-access
     chain_getHeader: () => this.registry.createType('Header', rpcHeader.result).toJSON(),
     state_getKeys: (): string[] => [],
     state_getKeysPaged: (): string[] => [],
@@ -112,7 +115,7 @@ export default class Mock implements ProviderInterface {
   }
 
   // eslint-disable-next-line @typescript-eslint/require-await
-  public async send (method: string, params: any[]): Promise<any> {
+  public async send (method: string, params: any[]): Promise<unknown> {
     if (!this.requests[method]) {
       throw new Error(`provider.send: Invalid method '${method}'`);
     }
@@ -121,11 +124,11 @@ export default class Mock implements ProviderInterface {
   }
 
   // eslint-disable-next-line @typescript-eslint/require-await
-  public async subscribe (type: string, method: string, ...params: any[]): Promise<number> {
+  public async subscribe (type: string, method: string, ...params: unknown[]): Promise<number> {
     l.debug((): any => ['subscribe', method, params]);
 
     if (this.subscriptions[method]) {
-      const callback: MockStateSubscriptionCallback = params.pop();
+      const callback = params.pop() as MockStateSubscriptionCallback;
       const id = ++this.subscriptionId;
 
       this.subscriptions[method].callbacks[id] = callback;

packages/rpc-provider/src/mock/send.spec.ts

@@ -18,7 +18,7 @@ describe('send', (): void => {
     return mock
       .send('something_invalid', [])
       .catch((error): void => {
-        expect(error.message).toMatch(/Invalid method/);
+        expect((error as Error).message).toMatch(/Invalid method/);
       });
   });
 

packages/rpc-provider/src/mock/subscribe.spec.ts

@@ -18,7 +18,7 @@ describe('subscribe', (): void => {
     return mock
       .subscribe('test', 'test_notFound')
       .catch((error): void => {
-        expect(error.message).toMatch(/Invalid method 'test_notFound'/);
+        expect((error as Error).message).toMatch(/Invalid method 'test_notFound'/);
       });
   });
 
@@ -41,7 +41,7 @@ describe('subscribe', (): void => {
   });
 
   it('calls back with new headers', (done): Promise<number> => {
-    return mock.subscribe('chain_newHead', 'chain_subscribeNewHead', (_: any, header: any): void => {
+    return mock.subscribe('chain_newHead', 'chain_subscribeNewHead', (_: any, header: { number: number }): void => {
       if (header.number === 4) {
         done();
       }
@@ -51,7 +51,7 @@ describe('subscribe', (): void => {
   it('handles errors withing callbacks gracefully', (done): Promise<number> => {
     let hasThrown = false;
 
-    return mock.subscribe('chain_newHead', 'chain_subscribeNewHead', (_: any, header: any): void => {
+    return mock.subscribe('chain_newHead', 'chain_subscribeNewHead', (_: any, header: { number: number }): void => {
       if (!hasThrown) {
         hasThrown = true;