Bug 1462811 - allow task template to set taskGroupId

docs/firing-hooks.md

@@ -12,7 +12,8 @@ A hook can be "fired" in a variety of ways:
 In each case, the hooks service creates a task based on the hook definition and
 submits it to the Queue service via `Queue.createTask`.
 
-Such tasks always have `taskGroupId` equal to their `taskId`.
+If the task definition does not specify a `taskGroupId`, it is set the created
+task's `taskId`.
 
 ## JSON-e Rendering
 
@@ -23,8 +24,8 @@ fired, that template is rendered and the result is submitted to
 
 The context for that rendering is an object with property `firedBy`, giving the
 action that led to the hook firing; as well as `taskId` giving the taskId (and
-taskGroupId) of the task being created. The other properties of the object vary
-depending on the `firedBy` property.
+default `taskGroupId`) of the task being created. The other properties of the
+object vary depending on the `firedBy` property.
 
 ### Scheduled Tasks
 

src/taskcreator.js

@@ -32,9 +32,13 @@ class TaskCreator {
     if (!task.expires) {
       task.expires = taskcluster.fromNowJSON(hook.expires, created);
     }
-    // set the taskGroupId to the taskId, thereby creating a new task group
-    // and following the convention for decision tasks.
-    task.taskGroupId = options.taskId;
+
+    // If the template did not set a taskGroupId, then set the taskGroupId to
+    // the taskId, thereby creating a new task group and following the
+    // convention for decision tasks.
+    if (!task.taskGroupId) {
+      task.taskGroupId = options.taskId;
+    }
     return task;
   }
 

test/taskcreator_test.js

@@ -129,6 +129,7 @@ suite('taskcreator_test.js', function() {
         firedBy: 'schedule',
       }, {taskId});
       const task = await fetchFiredTask(taskId);
+      assume(taskId).equals(task.taskGroupId); // the default
       assume(task.extra).deeply.equals({
         context: {
           valueFromContext: 55,
@@ -144,13 +145,24 @@ suite('taskcreator_test.js', function() {
       hook.task.then.created = {$fromNow: '0 seconds'};
       hook.task.then.deadline = {$fromNow: '1 minute'};
       hook.task.then.expires = {$fromNow: '2 minutes'};
-      return await helper.Hook.create(hook);
+      await helper.Hook.create(hook);
+      let taskId = taskcluster.slugid();
+      let resp = await creator.fire(hook, {}, {taskId});
+
+      const task = await fetchFiredTask(taskId);
+      assume(new Date(task.deadline) - new Date(task.created)).to.equal(60000);
+      assume(new Date(task.expires) - new Date(task.created)).to.equal(120000);
+    });
+
+    test('firing a real task that sets its own taskGroupId works', async function() {
+      let hook = _.cloneDeep(defaultHook);
+      hook.task.then.taskGroupId = taskcluster.slugid();
+      await helper.Hook.create(hook);
       let taskId = taskcluster.slugid();
       let resp = await creator.fire(hook, {}, {taskId});
 
       const task = await fetchFiredTask(taskId);
-      assume(new Date(task.expires) - new Date(task.created)).to.equal(60000);
-      assume(new Date(task.deadline) - new Date(task.created)).to.equal(120000);
+      assume(task.taskGroupId).equals(hook.task.then.taskGroupId);
     });
 
     test('firing a real task includes values from context', async function() {