Merge pull request #39 from val-town/master

Enable socket to be closed

Author: KallynGowdy

src/DenoWorker.spec.ts

@@ -23,6 +23,13 @@ describe('DenoWorker', () => {
     const envFile = path.resolve(__dirname, './test/env.js');
     const envScript = readFileSync(envFile, { encoding: 'utf-8' });
     const memoryCrashFile = path.resolve(__dirname, './test/memory.js');
+    const unresolvedPromiseFile = path.resolve(
+        __dirname,
+        './test/unresolved_promise.js'
+    );
+    const unresolvedPromiseScript = readFileSync(unresolvedPromiseFile, {
+        encoding: 'utf-8',
+    });
 
     afterEach(() => {
         if (worker) {
@@ -1147,6 +1154,42 @@ describe('DenoWorker', () => {
             worker.terminate();
         });
     });
+
+    describe('closeSocket()', () => {
+        it('should allow natural exit if closeSocket is called after message is received', async () => {
+            worker = new DenoWorker(unresolvedPromiseScript);
+
+            let resolveExit: any;
+            let exit = new Promise((resolve) => {
+                resolveExit = resolve;
+            });
+            worker.onexit = () => resolveExit();
+
+            await new Promise<void>(
+                (resolve) =>
+                    (worker.onmessage = (e) => {
+                        worker.closeSocket();
+                        resolve();
+                    })
+            );
+
+            await exit;
+        });
+
+        it('should allow natural exit if closeSocket is called before socket is open', async () => {
+            worker = new DenoWorker(unresolvedPromiseScript);
+
+            let resolveExit: any;
+            let exit = new Promise((resolve) => {
+                resolveExit = resolve;
+            });
+            worker.onexit = () => resolveExit();
+
+            worker.closeSocket();
+
+            await exit;
+        });
+    });
 });
 
 async function getDenoProcesses() {

src/DenoWorker.ts

@@ -159,6 +159,7 @@ export class DenoWorker {
     private _server: WSServer;
     private _process: ChildProcess;
     private _socket: WebSocket;
+    private _socketClosed: boolean;
     private _onmessageListeners: OnMessageListener[];
     private _onexitListeners: OnExitListener[];
     private _available: boolean;
@@ -178,6 +179,7 @@ export class DenoWorker {
         this._onexitListeners = [];
         this._pendingMessages = [];
         this._available = false;
+        this._socketClosed = false;
         this._stdout = new Readable();
         this._stdout.setEncoding('utf-8');
         this._stderr = new Readable();
@@ -212,6 +214,11 @@ export class DenoWorker {
                 socket.close();
                 return;
             }
+            if (this._socketClosed) {
+                socket.close();
+                this._socket = null;
+                return;
+            }
             this._socket = socket;
             socket.on('message', (message) => {
                 if (typeof message === 'string') {
@@ -419,11 +426,23 @@ export class DenoWorker {
         return this._postMessage(null, data, transfer);
     }
 
+    /**
+     * Closes the websocket, which may allow the process to exit natually.
+     */
+    closeSocket() {
+        this._socketClosed = true;
+        if (this._socket) {
+            this._socket.close();
+            this._socket = null;
+        }
+    }
+
     /**
      * Terminates the worker and cleans up unused resources.
      */
     terminate() {
         this._terminated = true;
+        this._socketClosed = true;
         if (this._process && this._process.exitCode === null) {
             // this._process.kill();
             forceKill(this._process.pid);

src/test/unresolved_promise.js

@@ -0,0 +1,2 @@
+new Promise(() => {});
+self.postMessage({ type: 'ready' });