Add contract fees (#875)

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

@@ -16,12 +16,8 @@ export function fees (api: ApiInterface$Rx) {
     return (combineLatest([
       api.query.balances.creationFee(),
       api.query.balances.existentialDeposit(),
-      api.query.fees
-        ? api.query.fees.transactionBaseFee()
-        : api.query.balances.transactionBaseFee(),
-      api.query.fees
-        ? api.query.fees.transactionByteFee()
-        : api.query.balances.transactionByteFee(),
+      api.query.balances.transactionBaseFee(),
+      api.query.balances.transactionByteFee(),
       api.query.balances.transferFee()
     ]) as any as Observable<[BN, BN, BN, BN, BN]>).pipe(
       map(([creationFee, existentialDeposit, transactionBaseFee, transactionByteFee, transferFee]) => ({
@@ -32,6 +28,6 @@ export function fees (api: ApiInterface$Rx) {
         transferFee
       })),
       drr()
-    ) ;
+    );
   };
 }

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

@@ -0,0 +1,60 @@
+// Copyright 2017-2019 @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 { ApiInterface$Rx, QueryableStorageFunctionBase } from '@polkadot/api/types';
+import { Codec } from '@polkadot/types/types';
+import { DerivedContractFees } from '../types';
+
+import BN from 'bn.js';
+import { Observable, combineLatest, of } from 'rxjs';
+import { map } from 'rxjs/operators';
+
+import { drr } from '../util/drr';
+
+// TODO The contracts API is still in flux, so some of these may disappear or re-appear or get replaced. Instead of
+// failing here, do best effort - if something does not exist, return 0 for the specific value. Should be removed
+// when actually stable and no more changes expected
+function nonexistentZero (fn: QueryableStorageFunctionBase<Observable<Codec>, Observable<Codec>>): Observable<BN> {
+  return fn
+    ? fn() as any as Observable<BN>
+    : of(new BN(0));
+}
+
+/**
+ * Get the balances for all intentions and their nominators
+ */
+export function fees (api: ApiInterface$Rx) {
+  // TODO Once we have muti support for disjointed queries, add here (so we make a single
+  // query for all these to the node).
+  return (): Observable<DerivedContractFees> => {
+    return (combineLatest([
+      nonexistentZero(api.query.contract.callBaseFee),
+      nonexistentZero(api.query.contract.contractFee),
+      nonexistentZero(api.query.contract.createBaseFee),
+      nonexistentZero(api.query.contract.creationFee),
+      nonexistentZero(api.query.contract.rentByteFee),
+      nonexistentZero(api.query.contract.rentDepositOffset),
+      nonexistentZero(api.query.contract.transactionBaseFee),
+      nonexistentZero(api.query.contract.transactionByteFee),
+      nonexistentZero(api.query.contract.transferFee),
+      nonexistentZero(api.query.contract.tombstoneDeposit)
+    ]) as any as Observable<Array<BN>>).pipe(
+      map(([callBaseFee, contractFee, createBaseFee, creationFee, rentByteFee, rentDepositOffset, transactionBaseFee, transactionByteFee, transferFee, tombstoneDeposit]) => {
+        return {
+          callBaseFee,
+          contractFee,
+          createBaseFee,
+          creationFee,
+          rentByteFee,
+          rentDepositOffset,
+          transactionBaseFee,
+          transactionByteFee,
+          transferFee,
+          tombstoneDeposit
+        };
+      }),
+      drr()
+    );
+  };
+}

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

@@ -0,0 +1,5 @@
+// Copyright 2017-2019 @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 * from './fees';

packages/api-derive/src/index.ts

@@ -8,6 +8,7 @@ import { ApiInterface$Rx } from '@plugnet/api/types';
 import * as accounts from './accounts';
 import * as balances from './balances';
 import * as chain from './chain';
+import * as contract from './contract';
 import * as democracy from './democracy';
 import * as session from './session';
 import * as staking from './staking';
@@ -37,6 +38,7 @@ export interface Derive {
   accounts: ReturnTypes<typeof accounts>;
   balances: ReturnTypes<typeof balances>;
   chain: ReturnTypes<typeof chain>;
+  contract: ReturnTypes<typeof contract>;
   democracy: ReturnTypes<typeof democracy>;
   session: ReturnTypes<typeof session>;
   staking: ReturnTypes<typeof staking>;

packages/api-derive/src/types.ts

@@ -32,3 +32,16 @@ export type DerivedReferendumVote = {
   balance: Balance,
   vote: Vote
 };
+
+export type DerivedContractFees = {
+  callBaseFee: BN,
+  contractFee: BN,
+  createBaseFee: BN,
+  creationFee: BN,
+  rentByteFee: BN,
+  rentDepositOffset: BN,
+  transactionBaseFee: BN,
+  transactionByteFee: BN,
+  transferFee: BN,
+  tombstoneDeposit: BN
+};