Scheduler: return task id form Scheduler.add

Closes: #1635

PR-URL: #1638

CHANGELOG.md

@@ -3,6 +3,7 @@
 ## [Unreleased][unreleased]
 
 - Allow third party plugins (not only metarhia npm modules)
+- Scheduler: return task id from `Scheduler.add(task: Task): Promise<string>`
 
 ## [2.5.3][] - 2021-08-19
 

impress.js

@@ -88,7 +88,10 @@ const CTRL_C = 3;
     worker.on('message', (data) => {
       if (data.type === 'event') {
         if (data.name === 'started') active++;
-        if (data.name.startsWith('task:')) scheduler.postMessage(data);
+        if (data.name.startsWith('task:')) {
+          const transferList = data.port ? [data.port] : undefined;
+          scheduler.postMessage(data, transferList);
+        }
       }
       if (active === count && startTimer) {
         clearTimeout(startTimer);

lib/scheduler.js

@@ -27,11 +27,11 @@ class Scheduler {
   async load() {
     this.executor = true;
 
-    worker.parentPort.on('message', async (data) => {
-      if (data.type !== 'event') return;
-      if (data.name === 'task:add') this.add(data.task);
-      else if (data.name === 'task:remove') this.remove(data.task.id);
-      else if (data.name === 'task:stop') this.stop(data.task.name);
+    worker.parentPort.on('message', async ({ type, name, task, port }) => {
+      if (type !== 'event') return;
+      if (name === 'task:add') port.postMessage({ id: await this.add(task) });
+      else if (name === 'task:remove') this.remove(task.id);
+      else if (name === 'task:stop') this.stop(task.name);
     });
 
     const now = metautil.nowDate();
@@ -78,24 +78,29 @@ class Scheduler {
     return this.start(id);
   }
 
-  async add(record) {
+  async add(task) {
     if (!this.executor) {
-      const msg = { type: 'event', name: 'task:add', task: record };
-      worker.parentPort.postMessage(msg);
-      return;
+      const { port1, port2 } = new worker.MessageChannel();
+      const msg = { type: 'event', name: 'task:add', task, port: port1 };
+      return new Promise((resolve) => {
+        port2.on('message', ({ id }) => {
+          resolve(id);
+        });
+        worker.parentPort.postMessage(msg, [port1]);
+      });
     }
     const id = metautil.nowDate() + '-id-' + this.nextId.toString();
     this.nextId++;
-    const task = { id, ...record };
-    const started = this.restore(task);
-    if (!started) return;
+    const started = this.restore({ id, ...task });
+    if (!started) return id;
     const filePath = path.join(this.path, id + '.json');
     try {
       const data = JSON.stringify(task);
       await fsp.writeFile(filePath, data);
     } catch (err) {
       this.application.console.error(err.stack);
     }
+    return id;
   }
 
   async remove(id) {

types/core.d.ts

@@ -6,7 +6,7 @@ export interface Task {
 }
 
 export interface Scheduler {
-  add(task: Task): void;
+  add(task: Task): Promise<string>;
   remove(id: string): void;
   stop(name: string): void;
 }