*Add support for a stream being canceled or aborted

src/rpc/connection.ts

@@ -8,8 +8,13 @@ import { pack, unpack } from "msgpackr";
 import log from "loglevel";
 import { getRpcServer } from "./server";
 
+interface CancelRequest {
+  cancel: true;
+}
+
 export default class RPCConnection {
   private _socket: any;
+  private _canceled = false;
   constructor(socket: any) {
     this._socket = socket;
     socket.rawStream._ondestroy = () => false;
@@ -19,9 +24,21 @@ export default class RPCConnection {
   private async checkRpc(data: Buffer) {
     if (data.toString() === "rpc") {
       this._socket.once("data", this.processRequest);
+      this._socket.on("data", this.listenForCancel);
     }
   }
+  private async listenForCancel(data: Buffer) {
+    let request: any;
+    try {
+      request = unpack(data) as CancelRequest;
+    } catch (e) {
+      return;
+    }
 
+    if (request.cancel) {
+      this._canceled = true;
+    }
+  }
   private async processRequest(data: Buffer) {
     let request: RPCRequest;
     try {
@@ -44,6 +61,9 @@ export default class RPCConnection {
         } as StreamFileResponse,
       };
       for await (const chunk of stream) {
+        if (this._canceled) {
+          break;
+        }
         streamResp.data.data = chunk as unknown as Uint8Array;
         that.write(pack(streamResp));
       }
@@ -61,7 +81,9 @@ export default class RPCConnection {
       that.end();
       return;
     }
+    if (!this._canceled) {
       that.write(pack(response));
+    }
     that.end();
   }
 }