Introduce lock to prevent parallel task execution (#9858)

Signed-off-by: Thomas Mäder <[email protected]>

packages/core/src/common/promise-util.ts

@@ -44,7 +44,7 @@ export function timeout(ms: number, token = CancellationToken.None): Promise<voi
     return deferred.promise;
 }
 
-export async function retry<T>(task: () => Promise<T>, delay: number, retries: number): Promise<T> {
+export async function retry<T>(task: () => Promise<T>, retryDelay: number, retries: number): Promise<T> {
     let lastError: Error | undefined;
 
     for (let i = 0; i < retries; i++) {
@@ -53,9 +53,29 @@ export async function retry<T>(task: () => Promise<T>, delay: number, retries: n
         } catch (error) {
             lastError = error;
 
-            await timeout(delay);
+            await timeout(retryDelay);
         }
     }
 
     throw lastError;
 }
+
+/**
+ * A function to allow a promise resolution to be delayed by a number of milliseconds. Usage is as follows:
+ *
+ * `const stringValue = await myPromise.then(delay(600)).then(value => value.toString());`
+ *
+ * @param ms the number of millisecond to delay
+ * @returns a function that returns a promise that returns the given value, but delayed
+ */
+export function delay<T>(ms: number): (value: T) => Promise<T> {
+    return value => new Promise((resolve, reject) => { setTimeout(() => resolve(value), ms); });
+}
+
+/**
+ * Constructs a promise that will resolve after a given delay.
+ * @param ms the number of milliseconds to wait
+ */
+export async function wait(ms: number): Promise<void> {
+    await delay(ms)(undefined);
+}

packages/task/package.json

@@ -16,7 +16,8 @@
     "@theia/workspace": "1.16.0",
     "ajv": "^6.5.3",
     "jsonc-parser": "^2.2.0",
-    "p-debounce": "^2.1.0"
+    "p-debounce": "^2.1.0",
+    "async-mutex": "^0.3.1"
   },
   "publishConfig": {
     "access": "public"

packages/task/src/browser/task-service.ts

@@ -65,6 +65,7 @@ import { TaskNode } from './task-node';
 import { MonacoWorkspace } from '@theia/monaco/lib/browser/monaco-workspace';
 import { TaskTerminalWidgetManager } from './task-terminal-widget-manager';
 import { ShellTerminalServerProxy } from '@theia/terminal/lib/common/shell-terminal-protocol';
+import { Mutex } from 'async-mutex';
 
 export interface QuickPickProblemMatcherItem {
     problemMatchers: NamedProblemMatcher[] | undefined;
@@ -100,6 +101,8 @@ export class TaskService implements TaskConfigurationClient {
         isBackgroundTaskEnded: Deferred<boolean | undefined>
     }>();
 
+    protected taskStartingLock: Mutex = new Mutex();
+
     @inject(FrontendApplication)
     protected readonly app: FrontendApplication;
 
@@ -727,34 +730,50 @@ export class TaskService implements TaskConfigurationClient {
     }
 
     async runTask(task: TaskConfiguration, option?: RunTaskOption): Promise<TaskInfo | undefined> {
-        const runningTasksInfo: TaskInfo[] = await this.getRunningTasks();
+        console.debug('entering runTask');
+        const releaseLock = await this.taskStartingLock.acquire();
+        console.debug('got lock');
 
-        // check if the task is active
-        const matchedRunningTaskInfo = runningTasksInfo.find(taskInfo => {
-            const taskConfig = taskInfo.config;
-            return this.taskDefinitionRegistry.compareTasks(taskConfig, task);
-        });
-        if (matchedRunningTaskInfo) { // the task is active
-            const taskName = this.taskNameResolver.resolve(task);
-            const terminalId = matchedRunningTaskInfo.terminalId;
-            if (terminalId) {
-                const terminal = this.terminalService.getByTerminalId(terminalId);
-                if (terminal) {
-                    if (TaskOutputPresentation.shouldSetFocusToTerminal(task)) { // assign focus to the terminal if presentation.focus is true
-                        this.terminalService.open(terminal, { mode: 'activate' });
-                    } else if (TaskOutputPresentation.shouldAlwaysRevealTerminal(task)) { // show the terminal but not assign focus
-                        this.terminalService.open(terminal, { mode: 'reveal' });
+        try {
+            const runningTasksInfo: TaskInfo[] = await this.getRunningTasks();
+            // check if the task is active
+            const matchedRunningTaskInfo = runningTasksInfo.find(taskInfo => {
+                const taskConfig = taskInfo.config;
+                return this.taskDefinitionRegistry.compareTasks(taskConfig, task);
+            });
+            console.debug(`running task ${JSON.stringify(task)}, already running = ${!!matchedRunningTaskInfo}`);
+
+            if (matchedRunningTaskInfo) { // the task is active
+                releaseLock();
+                console.debug('released lock');
+                const taskName = this.taskNameResolver.resolve(task);
+                const terminalId = matchedRunningTaskInfo.terminalId;
+                if (terminalId) {
+                    const terminal = this.terminalService.getByTerminalId(terminalId);
+                    if (terminal) {
+                        if (TaskOutputPresentation.shouldSetFocusToTerminal(task)) { // assign focus to the terminal if presentation.focus is true
+                            this.terminalService.open(terminal, { mode: 'activate' });
+                        } else if (TaskOutputPresentation.shouldAlwaysRevealTerminal(task)) { // show the terminal but not assign focus
+                            this.terminalService.open(terminal, { mode: 'reveal' });
+                        }
                     }
                 }
+                const selectedAction = await this.messageService.info(`The task '${taskName}' is already active`, 'Terminate Task', 'Restart Task');
+                if (selectedAction === 'Terminate Task') {
+                    await this.terminateTask(matchedRunningTaskInfo);
+                } else if (selectedAction === 'Restart Task') {
+                    return this.restartTask(matchedRunningTaskInfo, option);
+                }
+            } else { // run task as the task is not active
+                console.debug('task about to start');
+                const taskInfo = await this.doRunTask(task, option);
+                releaseLock();
+                console.debug('release lock 2');
+                return taskInfo;
             }
-            const selectedAction = await this.messageService.info(`The task '${taskName}' is already active`, 'Terminate Task', 'Restart Task');
-            if (selectedAction === 'Terminate Task') {
-                await this.terminateTask(matchedRunningTaskInfo);
-            } else if (selectedAction === 'Restart Task') {
-                return this.restartTask(matchedRunningTaskInfo, option);
-            }
-        } else { // run task as the task is not active
-            return this.doRunTask(task, option);
+        } catch (e) {
+            releaseLock();
+            throw e;
         }
     }
 

yarn.lock

@@ -2269,6 +2269,13 @@ async-limiter@~1.0.0:
   resolved "https://registry.yarnpkg.com/async-limiter/-/async-limiter-1.0.1.tgz#dd379e94f0db8310b08291f9d64c3209766617fd"
   integrity sha512-csOlWGAcRFJaI6m+F2WKdnMKr4HhdhFVBk0H/QbJFMCr+uO2kwohwXQPxw/9OCxp05r5ghVBFSyioixx3gfkNQ==
 
+async-mutex@^0.3.1:
+  version "0.3.1"
+  resolved "https://registry.yarnpkg.com/async-mutex/-/async-mutex-0.3.1.tgz#7033af665f1c7cebed8b878267a43ba9e77c5f67"
+  integrity sha512-vRfQwcqBnJTLzVQo72Sf7KIUbcSUP5hNchx6udI1U6LuPQpfePgdjJzlCe76yFZ8pxlLjn9lwcl/Ya0TSOv0Tw==
+  dependencies:
+    tslib "^2.1.0"
+
 async@^1.5.0:
   version "1.5.2"
   resolved "https://registry.yarnpkg.com/async/-/async-1.5.2.tgz#ec6a61ae56480c0c3cb241c95618e20892f9672a"
@@ -10224,6 +10231,11 @@ tslib@^1.10.0, tslib@^1.8.0, tslib@^1.8.1, tslib@^1.9.0:
   resolved "https://registry.yarnpkg.com/tslib/-/tslib-1.14.1.tgz#cf2d38bdc34a134bcaf1091c41f6619e2f672d00"
   integrity sha512-Xni35NKzjgMrwevysHTCArtLDpPvye8zV/0E4EyYn43P7/7qvQwPh9BGkHewbMulVntbigmcT7rdX3BNo9wRJg==
 
+tslib@^2.1.0:
+  version "2.3.1"
+  resolved "https://registry.yarnpkg.com/tslib/-/tslib-2.3.1.tgz#e8a335add5ceae51aa261d32a490158ef042ef01"
+  integrity sha512-77EbyPPpMz+FRFRuAFlWMtmgUWGe9UOG2Z25NqCwiIjRhOf5iKGuzSe5P2w1laq+FkRy4p+PCuVkJSGkzTEKVw==
+
 tslint@^5.12.0:
   version "5.20.1"
   resolved "https://registry.yarnpkg.com/tslint/-/tslint-5.20.1.tgz#e401e8aeda0152bc44dd07e614034f3f80c67b7d"