[jobs] Delete tasks with no job due to Redis error

Removes the newly created ScheduledTask from the database if
the job could not be enqueued due to a Redis connection error.

Signed-off-by: Eva Millán <evamillan@bitergia.com>

releases/unreleased/delete-task-on-error.yml

@@ -0,0 +1,11 @@
+---
+title: Remove tasks that fail to be scheduled
+category: fixed
+author: Eva Millan <evamillan@bitergia.com>
+issue: null
+notes: >
+  When there was an issue with the Redis connection when
+  a task was created, the task was added to the database
+  but there was not scheduled job linked to it. Tasks are 
+  now removed from the database and an error is raised in
+  this case.

sortinghat/core/jobs.py

@@ -28,9 +28,10 @@
 import django_rq.utils
 import pandas
 import rq
+import redis.exceptions
 
-from .db import find_individual_by_uuid, find_organization, add_scheduled_task
-from .api import enroll, merge, update_profile
+from .db import find_individual_by_uuid, find_organization
+from .api import enroll, merge, update_profile, add_scheduled_task, delete_scheduled_task
 from .context import SortingHatContext
 from .decorators import job_using_tenant, job_callback_using_tenant
 from .errors import BaseError, NotFoundError, EqualIndividualError, InvalidValueError
@@ -774,12 +775,16 @@ def create_scheduled_task(ctx, job, interval, params):
 
     trxl = TransactionsLog.open('create_scheduled_task', ctx)
 
-    task = add_scheduled_task(trxl, job, interval, params)
+    task = add_scheduled_task(ctx, job, interval, params)
 
     if not params:
         params = dict()
 
-    schedule_task(ctx, job_fn, task, **params)
+    try:
+        schedule_task(ctx, job_fn, task, **params)
+    except redis.exceptions.ConnectionError as e:
+        delete_scheduled_task(ctx, task.id)
+        raise(e)
 
     trxl.close()