feat: support promises

Author: xnerhu

packages/rpc-core/src/communication/channel.ts

@@ -1,4 +1,4 @@
-import { RpcScaffold } from '../interfaces';
+import { PromiseScaffold, RpcScaffold } from '../interfaces';
 
 const channels: string[] = [];
 
@@ -11,13 +11,13 @@ export abstract class Channel<T extends RpcScaffold<T>> {
 
   protected abstract createReceiver(...args: any[]): any;
 
-  protected abstract createInvoker(...args: any[]): T;
+  protected abstract createInvoker(...args: any[]): T | PromiseScaffold<T>;
 
   public abstract getReceiver(...args: any[]): any;
 
-  public abstract getInvoker(...args: any[]): T;
-
   public destroy() {
     channels.splice(channels.indexOf(this.name), 1);
   }
+
+  public abstract getInvoker(...args: any[]): T | PromiseScaffold<T>;
 }

packages/rpc-core/src/communication/multi-receiver-channel.ts

@@ -1,4 +1,4 @@
-import { RpcScaffold } from '..';
+import { PromiseScaffold, RpcScaffold } from '..';
 import { Channel } from './channel';
 
 export abstract class MultiReceiverChannel<
@@ -12,7 +12,7 @@ export abstract class MultiReceiverChannel<
     return this.receivers.get(args);
   }
 
-  public getInvoker(...args: any[]): T {
+  public getInvoker(...args: any[]): PromiseScaffold<T> {
     return this.createInvoker(...args);
   }
 

packages/rpc-core/src/communication/single-receiver-channel.ts

@@ -20,7 +20,7 @@ export abstract class SingleReceiverChannel<
   public getInvoker(...args: any[]): T {
     if (this.isReceiver() && process?.env?.TEST !== 'true')
       throw new Error('This context cannot invoke remote methods.');
-    return this.createInvoker(...args);
+    return this.createInvoker(...args) as T;
   }
 
   public abstract isReceiver(): boolean;

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

@@ -1,2 +1,3 @@
 export * from './rpc';
-export * from './utils';
+export * from './utils';
+export * from './promise';

packages/rpc-core/src/interfaces/promise.ts

@@ -0,0 +1,3 @@
+export type UnwrapPromise<T> = T extends PromiseLike<infer U> ? U : T;
+
+export type OptionalPromise<T> = Promise<T> | T;

packages/rpc-core/src/interfaces/rpc.ts

@@ -1,3 +1,4 @@
+import { OptionalPromise, UnwrapPromise } from './promise';
 import { AnyFunction } from './utils';
 
 export type RpcScaffold<T> = {
@@ -35,3 +36,21 @@ export interface ServiceCaller {
   cb: (obj: any) => Promise<any>;
   method: string;
 }
+
+export type OptionalPromiseScaffold<T extends RpcScaffold<T>> = {
+  [K in keyof T]: (
+    ...args: Parameters<T[K]>
+  ) => OptionalPromise<UnwrapPromise<ReturnType<T[K]>>>;
+};
+
+export type PromiseScaffold<T extends RpcScaffold<T>> = {
+  [K in keyof T]: (
+    ...args: Parameters<T[K]>
+  ) => Promise<UnwrapPromise<ReturnType<T[K]>>>;
+};
+
+export type SyncScaffold<T extends RpcScaffold<T>> = {
+  [K in keyof T]: (
+    ...args: Parameters<T[K]>
+  ) => UnwrapPromise<ReturnType<T[K]>>;
+};

packages/rpc-node/src/interfaces/worker.ts

@@ -1,12 +1,15 @@
 import {
+  OptionalPromiseScaffold,
+  PromiseScaffold,
   RpcEventBase,
   RpcHandler,
   RpcObserver,
   RpcScaffold,
+  SyncScaffold,
 } from '@wexond/rpc-core';
 
 export type RpcWorkerHandler<T extends RpcScaffold<T>> = RpcHandler<
-  T,
+  OptionalPromiseScaffold<T>,
   RpcWorkerEvent
 >;
 

packages/rpc-node/src/worker/worker-channel.ts

@@ -4,18 +4,19 @@ import {
   createServiceProxy,
   makeRandomId,
   RpcScaffold,
+  PromiseScaffold,
 } from '@wexond/rpc-core';
 import { WorkerReceiver } from './worker-receiver';
 import { RpcWorkerRequest, RpcWorkerResponse } from '../interfaces';
 
 export declare interface WorkerChannel<T> {
   getReceiver(port?: MessagePort | Worker): WorkerReceiver<T>;
-  getInvoker(port?: MessagePort | Worker): T;
+  getInvoker(port?: MessagePort | Worker): PromiseScaffold<T>;
 }
 export class WorkerChannel<
   T extends RpcScaffold<T>
 > extends MultiReceiverChannel<T> {
-  protected createInvoker(port?: MessagePort | Worker): T {
+  protected createInvoker(port?: MessagePort | Worker) {
     if (!port && !parentPort) throw new Error('Invalid MessagePort.');
 
     return createServiceProxy<T>((method, ...args: any[]) => {