feat(reactive-rpc): 🎸 add ability to store response codec in RpcCodec

Author: streamich

src/__tests__/reactive-rpc/uws/ws/rx-rpc/RpcPersistentClient.spec.ts

@@ -53,13 +53,13 @@ if (process.env.TEST_E2E) {
     const setup: ApiTestSetup = async () => {
       const port = +(process.env.PORT || 9999);
       const url = `ws://localhost:${port}/rpc`;
-      const codec = new RpcCodec(reqCodec, msgCodec);
+      const codec = new RpcCodec(msgCodec, reqCodec, resCodec);
       const client = new RpcPersistentClient({
         codec,
         channel: {
           newChannel: () =>
             new WebSocketChannel({
-              newSocket: () => new WebSocket(url, [protocolSpecifier]) as any,
+              newSocket: () => new WebSocket(url, [codec.specifier()]) as any,
             }),
         },
       });

src/reactive-rpc/common/codec/RpcCodec.ts

@@ -1,24 +1,30 @@
+import type {RpcSpecifier} from '../rpc';
 import type {ReactiveRpcMessage} from '../messages';
 import type {JsonValueCodec} from '../../../json-pack/codecs/types';
 import type {RpcMessageCodec} from './types';
 
 export class RpcCodec {
-  constructor(public readonly valueCodec: JsonValueCodec, public readonly messageCodec: RpcMessageCodec) {}
+  constructor(public readonly msg: RpcMessageCodec, public readonly req: JsonValueCodec, public readonly res: JsonValueCodec) {}
+
+  public specifier(): RpcSpecifier {
+    const specifier = `rpc.${this.msg.id}.${this.req.id}` + (this.req.id !== this.res.id ? `-${this.res.id}` : '');
+    return specifier as RpcSpecifier;
+  }
 
   public encode(messages: ReactiveRpcMessage[]): Uint8Array {
-    const valueCodec = this.valueCodec;
+    const valueCodec = this.res;
     const encoder = valueCodec.encoder;
     const writer = encoder.writer;
     writer.reset();
-    this.messageCodec.encodeBatch(valueCodec, messages);
+    this.msg.encodeBatch(valueCodec, messages);
     return writer.flush();
   }
 
   public decode(data: Uint8Array): ReactiveRpcMessage[] {
-    const valueCodec = this.valueCodec;
+    const valueCodec = this.req;
     const decoder = valueCodec.decoder;
     const reader = decoder.reader;
     reader.reset(data);
-    return this.messageCodec.decodeBatch(valueCodec, data);
+    return this.msg.decodeBatch(valueCodec, data);
   }
 }

src/reactive-rpc/common/rpc/__tests__/RpcPersistentClient.spec.ts

@@ -15,7 +15,7 @@ test('on remote method execution, sends message over WebSocket only once', async
   const ws = new Ws('');
   const valueCodecs = new Codecs(new Writer(128));
   const messageCodecs = new RpcMessageCodecs();
-  const codec = new RpcCodec(valueCodecs.cbor, messageCodecs.compact);
+  const codec = new RpcCodec(messageCodecs.compact, valueCodecs.cbor, valueCodecs.cbor);
   const client = new RpcPersistentClient({
     channel: {
       newChannel: () =>