Lazy decoration (part 9, rpc) (#4165)

* Lazy decoration (part 9, rpc)

* Flatten

* Cleanups (& bump dev, fix copy-to)

* Only RPC methods are lazy

* Decorate rpc-core lazily

* Adjust import

* Remove (now) invalid test

packages/rpc-core/src/bundle.ts

@@ -7,12 +7,12 @@ import type { StorageKey, Vec } from '@polkadot/types';
 import type { Hash } from '@polkadot/types/interfaces';
 import type { AnyJson, Codec, DefinitionRpc, DefinitionRpcExt, DefinitionRpcSub, Registry } from '@polkadot/types/types';
 import type { Memoized } from '@polkadot/util/types';
-import type { RpcInterface, RpcInterfaceMethod } from './types';
+import type { RpcInterfaceMethod } from './types';
 
 import { Observable, publishReplay, refCount } from 'rxjs';
 
 import { rpcDefinitions } from '@polkadot/types';
-import { assert, hexToU8a, isFunction, isNull, isUndefined, logger, memoize, u8aToU8a } from '@polkadot/util';
+import { assert, hexToU8a, isFunction, isNull, isUndefined, lazyMethod, logger, memoize, objectSpread, u8aToU8a } from '@polkadot/util';
 
 import { drr, refCountDelay } from './util';
 
@@ -141,44 +141,41 @@ export class RpcCore {
     });
   }
 
-  public addUserInterfaces<Section extends keyof RpcInterface> (userRpc: Record<string, Record<string, DefinitionRpc | DefinitionRpcSub>>): void {
+  public addUserInterfaces (userRpc: Record<string, Record<string, DefinitionRpc | DefinitionRpcSub>>): void {
     // add any extra user-defined sections
-    this.sections.push(...Object.keys(userRpc).filter((key) => !this.sections.includes(key)));
+    this.sections.push(...Object.keys(userRpc).filter((k) => !this.sections.includes(k)));
 
-    // decorate the sections with base and user methods
-    this.sections.forEach((sectionName): void => {
-      (this as Record<string, unknown>)[sectionName as Section] ||= {};
+    for (let s = 0; s < this.sections.length; s++) {
+      const section = this.sections[s];
+      const defs = objectSpread<Record<string, DefinitionRpc | DefinitionRpcSub>>({}, rpcDefinitions[section as 'babe'], userRpc[section]);
+      const methods = Object.keys(defs);
 
-      const section = (this as Record<string, unknown>)[sectionName as Section] as Record<string, unknown>;
+      for (let m = 0; m < methods.length; m++) {
+        const method = methods[m];
+        const def = defs[method];
 
-      Object
-        .entries({
-          ...this._createInterface(sectionName, rpcDefinitions[sectionName as 'babe'] || {}),
-          ...this._createInterface(sectionName, userRpc[sectionName] || {})
-        })
-        .forEach(([key, value]): void => {
-          section[key] ||= value;
-        });
-    });
+        if (!this.mapping.has(def.endpoint || `${section}_${method}`)) {
+          if (!(this as Record<string, unknown>)[section]) {
+            (this as Record<string, unknown>)[section] = {};
+          }
+
+          lazyMethod(this[section as 'connect'], method, () =>
+            this._createInterface(section, method, def)
+          );
+        }
+      }
+    }
   }
 
-  private _createInterface<Section extends keyof RpcInterface> (section: string, methods: Record<string, DefinitionRpc | DefinitionRpcSub>): RpcInterface[Section] {
-    return Object
-      .entries(methods)
-      .filter(([method, { endpoint }]) => !this.mapping.has(endpoint || `${section}_${method}`))
-      .reduce((exposed, [method, { endpoint }]): RpcInterface[Section] => {
-        const def = methods[method];
-        const isSubscription = !!(def as DefinitionRpcSub).pubsub;
-        const jsonrpc = endpoint || `${section}_${method}`;
+  private _createInterface (section: string, method: string, def: DefinitionRpc | DefinitionRpcSub): RpcInterfaceMethod {
+    const isSubscription = !!(def as DefinitionRpcSub).pubsub;
+    const jsonrpc = def.endpoint || `${section}_${method}`;
 
-        this.mapping.set(jsonrpc, { ...def, isSubscription, jsonrpc, method, section });
+    this.mapping.set(jsonrpc, { ...def, isSubscription, jsonrpc, method, section });
 
-        (exposed as Record<string, unknown>)[method] = isSubscription
-          ? this._createMethodSubscribe(section, method, def as DefinitionRpcSub)
-          : this._createMethodSend(section, method, def);
-
-        return exposed;
-      }, {} as RpcInterface[Section]);
+    return isSubscription
+      ? this._createMethodSubscribe(section, method, def as DefinitionRpcSub)
+      : this._createMethodSend(section, method, def);
   }
 
   private _memomize (creator: <T> (isScale: boolean) => (...values: unknown[]) => Observable<T>, def: DefinitionRpc): Memoized<RpcInterfaceMethod> {

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

@@ -1,11 +1,8 @@
 // Copyright 2017-2021 @polkadot/rpc-core authors & contributors
 // SPDX-License-Identifier: Apache-2.0
 
-import type { Observable } from 'rxjs';
 import type { RpcInterface } from '@polkadot/rpc-core/types.jsonrpc';
 
-import { of } from 'rxjs';
-
 import { MockProvider } from '@polkadot/rpc-provider/mock';
 import { TypeRegistry } from '@polkadot/types/create';
 
@@ -25,21 +22,6 @@ describe('replay', (): void => {
     await provider.disconnect();
   });
 
-  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
-        rpc.chain.getBlockHash
-      ).toHaveBeenCalledWith(123, false);
-
-      done();
-    });
-  });
-
   it('returns the observable value', (done): void => {
     rpc.system.chain().subscribe((value: any): void => {
       if (value) {

packages/rpc-core/src/types.jsonrpc.ts

@@ -4,11 +4,12 @@
 // FIXME, this whole file needs to move to API
 
 import type { Observable } from 'rxjs';
-import type { AnyFunction } from '@polkadot/types/types';
+import type { AnyFunction, DefinitionRpc } from '@polkadot/types/types';
 
 // eslint-disable-next-line @typescript-eslint/no-empty-interface
 export interface RpcInterface {}
 
 export type AugmentedRpc<F extends AnyFunction> = F & {
   raw: <T> (...params: Parameters<F>) => Observable<T>;
+  meta: DefinitionRpc;
 };