Remove explicit RpcCore interface (apply in API itself) (#3284)

* Remove explicit RpcCore interface (apply in API itself)

* Simplify

* Adjust test linting

* casting

* Remove stray eslint

* Re-add enable

packages/api/src/base/Decorate.ts

@@ -79,7 +79,7 @@ export abstract class Decorate<ApiType extends ApiTypes> extends Events {
 
   protected _rpc?: DecoratedRpc<ApiType, RpcInterface>;
 
-  protected _rpcCore: RpcCore;
+  protected _rpcCore: RpcCore & RpcInterface;
 
   protected _runtimeChain?: Text;
 
@@ -136,6 +136,7 @@ export abstract class Decorate<ApiType extends ApiTypes> extends Events {
 
     this.#instanceId = `${++instanceCounter}`;
     this.#registry = options.source?.registry || options.registry || new TypeRegistry();
+    this._rx.registry = this.#registry;
 
     const thisProvider = options.source
       ? options.source._rpcCore.provider.clone()
@@ -144,10 +145,11 @@ export abstract class Decorate<ApiType extends ApiTypes> extends Events {
     this._decorateMethod = decorateMethod;
     this._options = options;
     this._type = type;
-    this._rpcCore = new RpcCore(this.#instanceId, this.#registry, thisProvider, this._options.rpc);
+
+    // The RPC interface decorates the known interfaces on init
+    this._rpcCore = new RpcCore(this.#instanceId, this.#registry, thisProvider, this._options.rpc) as (RpcCore & RpcInterface);
     this._isConnected = new BehaviorSubject(this._rpcCore.provider.isConnected);
     this._rx.hasSubscriptions = this._rpcCore.provider.hasSubscriptions;
-    this._rx.registry = this.#registry;
   }
 
   /**
@@ -281,7 +283,7 @@ export abstract class Decorate<ApiType extends ApiTypes> extends Events {
       });
   }
 
-  protected _decorateRpc<ApiType extends ApiTypes> (rpc: RpcCore, decorateMethod: DecorateMethod<ApiType>, input: Partial<DecoratedRpc<ApiType, RpcInterface>> = {}): DecoratedRpc<ApiType, RpcInterface> {
+  protected _decorateRpc<ApiType extends ApiTypes> (rpc: RpcCore & RpcInterface, decorateMethod: DecorateMethod<ApiType>, input: Partial<DecoratedRpc<ApiType, RpcInterface>> = {}): DecoratedRpc<ApiType, RpcInterface> {
     return rpc.sections.reduce((out, _sectionName): DecoratedRpc<ApiType, RpcInterface> => {
       const sectionName = _sectionName as keyof DecoratedRpc<ApiType, RpcInterface>;
 

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

@@ -1,6 +1,8 @@
 // Copyright 2017-2021 @polkadot/rpc-core authors & contributors
 // SPDX-License-Identifier: Apache-2.0
 
+import type { RpcInterface } from '@polkadot/rpc-core/types.jsonrpc';
+
 import { createTestPairs } from '@polkadot/keyring/testingPairs';
 import { MockProvider } from '@polkadot/rpc-provider/mock';
 import { TypeRegistry } from '@polkadot/types/create';
@@ -9,11 +11,11 @@ import { RpcCore } from '.';
 
 describe('Cached Observables', (): void => {
   const registry = new TypeRegistry();
-  let rpc: RpcCore;
+  let rpc: RpcCore & RpcInterface;
   const keyring = createTestPairs();
 
   beforeEach((): void => {
-    rpc = new RpcCore('123', registry, new MockProvider(registry));
+    rpc = new RpcCore('123', registry, new MockProvider(registry)) as (RpcCore & RpcInterface);
   });
 
   it('creates a single observable for subscriptions (multiple calls)', (): void => {

packages/rpc-core/src/index.ts

@@ -79,7 +79,7 @@ function isTreatAsHex (key: StorageKey): boolean {
  * const rpc = new Rpc(provider);
  * ```
  */
-export class RpcCore implements RpcInterface {
+export class RpcCore {
   #instanceId: string;
 
   #registryDefault: Registry;
@@ -94,42 +94,6 @@ export class RpcCore implements RpcInterface {
 
   public readonly sections: string[] = [];
 
-  // Ok, this is quite horrible - we really should not be using the ! here, but we are actually assigning
-  // these via the createInterfaces inside the constructor. However... this is not quite visible. The reason
-  // why we don't do for individual assignments is to allow user-defined RPCs to also be defined
-
-  public readonly author!: RpcInterface['author'];
-
-  public readonly babe!: RpcInterface['babe'];
-
-  public readonly chain!: RpcInterface['chain'];
-
-  public readonly childstate!: RpcInterface['childstate'];
-
-  public readonly contracts!: RpcInterface['contracts'];
-
-  public readonly engine!: RpcInterface['engine'];
-
-  public readonly eth!: RpcInterface['eth'];
-
-  public readonly grandpa!: RpcInterface['grandpa'];
-
-  public readonly net!: RpcInterface['net'];
-
-  public readonly offchain!: RpcInterface['offchain'];
-
-  public readonly payment!: RpcInterface['payment'];
-
-  public readonly rpc!: RpcInterface['rpc'];
-
-  public readonly state!: RpcInterface['state'];
-
-  public readonly syncstate!: RpcInterface['syncstate'];
-
-  public readonly system!: RpcInterface['system'];
-
-  public readonly web3!: RpcInterface['web3'];
-
   /**
    * @constructor
    * Default constructor for the Api Object
@@ -148,6 +112,7 @@ export class RpcCore implements RpcInterface {
     // these are the base keys (i.e. part of jsonrpc)
     this.sections.push(...sectionNames);
 
+    // decorate all interfaces, defined and user on this instance
     this.addUserInterfaces(userRpc);
   }
 
@@ -187,7 +152,7 @@ export class RpcCore implements RpcInterface {
     this.sections.forEach((sectionName): void => {
       (this as Record<string, unknown>)[sectionName as Section] ||= {};
 
-      const section = this[sectionName as Section] as Record<string, unknown>;
+      const section = (this as Record<string, unknown>)[sectionName as Section] as Record<string, unknown>;
 
       Object
         .entries({

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

@@ -1,6 +1,7 @@
 // Copyright 2017-2021 @polkadot/rpc-core authors & contributors
 // SPDX-License-Identifier: Apache-2.0
 
+import type { RpcInterface } from '@polkadot/rpc-core/types.jsonrpc';
 import type { Observable } from '@polkadot/x-rxjs';
 
 import { MockProvider } from '@polkadot/rpc-provider/mock';
@@ -11,10 +12,10 @@ import { RpcCore } from '.';
 
 describe('replay', (): void => {
   const registry = new TypeRegistry();
-  let rpc: RpcCore;
+  let rpc: RpcCore & RpcInterface;
 
   beforeEach((): void => {
-    rpc = new RpcCore('653', registry, new MockProvider(registry));
+    rpc = new RpcCore('653', registry, new MockProvider(registry)) as (RpcCore & RpcInterface);
   });
 
   it('subscribes via the rpc section', (done): void => {