Commands: Adds `inspect.query_task` command

celery/bin/celery.py

@@ -646,18 +646,19 @@ class inspect(_RemoteControl):
     choices = {
         'active': (1.0, 'dump active tasks (being processed)'),
         'active_queues': (1.0, 'dump queues being consumed from'),
-        'scheduled': (1.0, 'dump scheduled tasks (eta/countdown/retry)'),
-        'reserved': (1.0, 'dump reserved tasks (waiting to be processed)'),
-        'stats': (1.0, 'dump worker statistics'),
-        'revoked': (1.0, 'dump of revoked task ids'),
-        'registered': (1.0, 'dump of registered tasks'),
-        'ping': (0.2, 'ping worker(s)'),
         'clock': (1.0, 'get value of logical clock'),
         'conf': (1.0, 'dump worker configuration'),
-        'report': (1.0, 'get bugreport info'),
-        'memsample': (1.0, 'sample memory (requires psutil)'),
         'memdump': (1.0, 'dump memory samples (requires psutil)'),
+        'memsample': (1.0, 'sample memory (requires psutil)'),
         'objgraph': (60.0, 'create object graph (requires objgraph)'),
+        'ping': (0.2, 'ping worker(s)'),
+        'query_task': (1.0, 'query for task information by id'),
+        'reserved': (1.0, 'dump reserved tasks (waiting to be processed)'),
+        'scheduled': (1.0, 'dump scheduled tasks (eta/countdown/retry)'),
+        'stats': (1.0, 'dump worker statistics'),
+        'registered': (1.0, 'dump of registered tasks'),
+        'report': (1.0, 'get bugreport info'),
+        'revoked': (1.0, 'dump of revoked task ids'),
     }
 
     def call(self, method, *args, **options):
@@ -670,6 +671,9 @@ class inspect(_RemoteControl):
     def conf(self, with_defaults=False, *args, **kwargs):
         return self.call('conf', with_defaults, **kwargs)
 
+    def query_task(self, *ids, **options):
+        return self.call('query_task', ids, **options)
+
 
 class control(_RemoteControl):
     """Workers remote control.

docs/userguide/monitoring.rst

@@ -142,6 +142,21 @@ Commands
 
         $ celery -A proj inspect stats
 
+* **inspect query_task**: Show information about task(s) by id.
+
+    Any worker having a task in this set of ids reserved/active will respond
+    with status and information.
+
+    .. code-block:: console
+
+        $ celery -A proj inspect query_task e9f6c8f0-fec9-4ae8-a8c6-cf8c8451d4f8
+
+    You can also query for information about multiple tasks:
+
+    .. code-block:: console
+
+        $ celery -A proj inspect query_task id1 id2 ... idN
+
 * **control enable_events**: Enable events
 
     .. code-block:: console