From b80e95b86fa4284b5f9512578bbe61fde2789587 Mon Sep 17 00:00:00 2001
From: Timur Shemsedinov <timur.shemsedinov@gmail.com>
Date: Mon, 30 Aug 2021 00:37:54 +0300
Subject: [PATCH] Scheduler: return task id form Scheduler.add

Closes: https://github.com/metarhia/impress/issues/1635

PR-URL: https://github.com/metarhia/impress/pull/1638
---
 CHANGELOG.md     |  1 +
 impress.js       |  5 ++++-
 lib/scheduler.js | 29 +++++++++++++++++------------
 types/core.d.ts  |  2 +-
 4 files changed, 23 insertions(+), 14 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index d8af161d..dcf21d97 100644
--- a/CHANGELOG.md
+++ b/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
 
diff --git a/impress.js b/impress.js
index c23226ee..b01bc669 100644
--- a/impress.js
+++ b/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);
diff --git a/lib/scheduler.js b/lib/scheduler.js
index 7fb76199..66854e39 100644
--- a/lib/scheduler.js
+++ b/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();
@@ -78,17 +78,21 @@ 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);
@@ -96,6 +100,7 @@ class Scheduler {
     } catch (err) {
       this.application.console.error(err.stack);
     }
+    return id;
   }
 
   async remove(id) {
diff --git a/types/core.d.ts b/types/core.d.ts
index 4acf54a5..b5ffd7ac 100644
--- a/types/core.d.ts
+++ b/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;
 }