Skip to main content

A Django app to run new background tasks from either admin or cron, and inspect task history from admin; based on django-rq

Project description

1   django-task

A Django app to run new background tasks from either admin or cron, and inspect task history from admin

1.1   Quickstart

  1. Install Django Task:
pip install django-task
  1. Add it to your `INSTALLED_APPS`:
    'django_rq',  # optional, if using TaskTheaded
  1. Add Django Task’s URL patterns:
urlpatterns = [
    path('django_task/', include('django_task.urls', namespace='django_task')),
  1. Configure Redis and RQ in (optional, if using TaskTheaded):
#REDIS_URL = 'redis://localhost:6379/0'
redis_host = os.environ.get('REDIS_HOST', 'localhost')
redis_port = 6379
REDIS_URL = 'redis://%s:%d/0' % (redis_host, redis_port)

    'default': {
        'BACKEND': 'redis_cache.RedisCache',

# RQ config

RQ_PREFIX = "myproject_"

        'URL': REDIS_URL,
        #'PASSWORD': 'some-password',
        'DEFAULT_TIMEOUT': 360,
        'URL': REDIS_URL,
        'DEFAULT_TIMEOUT': 500,
    QUEUE_LOW: {
        'URL': REDIS_URL,
        #'ASYNC': False,

Note: if you plan to install many instances of the project on the same server, for each instance use a specific value for RQ_PREFIX; for example:

INSTANCE_PREFIX = "myproject_"
    from project.settings.instance_prefix import *
except Exception as e:


  1. Customize django-task specific settings (optional):
DJANGOTASK_LOG_ROOT = os.path.abspath(os.path.join(BASE_DIR, '..', 'protected', 'tasklog'))
  1. Optionally, revoke pending tasks at startapp;

file main/

class MainConfig(AppConfig):


    def ready(self):

            from django_task.utils import revoke_pending_tasks
        except Exception as e:

1.2   Features


  • create async tasks either programmatically or from admin
  • monitor async tasks from admin
  • log all tasks in the database for later inspection
  • optionally save task-specific logs in a TextField and/or in a FileField


  1. each specific job is described my a Model derived from models.Task, which is responsible for:
    • selecting the name for the consumer queue among available queues
    • collecting and saving all parameters required by the associated job
    • running the specific job asyncronously
  2. a new job can be run either:
    • creating a Task from the Django admin
    • creating a Task from code, then calling
  3. job execution workflow:
    • job execution is triggered by
    • job will receive the, and retrieve paramerts from it
    • on start, job will update task status to ‘STARTED’ and save for reference
    • during execution, the job can update the progress indicator
    • on completion, task status is finally updated to either ‘SUCCESS’ or ‘FAILURE’
    • See for an example

1.4   App settings


Path for log files.

Default: None

Example: os.path.abspath(os.path.join(BASE_DIR, ‘..’, ‘protected’, ‘tasklog’))


When True, all task are execute syncronously (useful for debugging and unit testing).

Default: False


Enables low level tracing in - for debugging challenging race conditions

Default: False


Rejects task if not active worker is available for the specific task queue when is called

Default: False


Redis server to connect to

Default: ‘redis://localhost:6379/0’

1.5   Running Tests

Does the code actually work?

Running the unit tests from your project:

python test -v 2 django_task --settings=django_task.tests.settings

Running the unit tests from your local fork:

source <YOURVIRTUALENV>/bin/activate
(myenv) $ pip install tox
(myenv) $ tox


python ./


coverage run --source='.'
coverage report

1.6   Threaded vs RQ-based tasks

The original implementation is based on django-rq and RQ (a Redis based Python queuing library).

On some occasions, using a background queue may be overkill or even inappropriate: if you need to run many short I/O-bound background tasks concurrently, the serialization provided by the queue, while limiting the usage of resources, would cause eccessive delay.

Starting from version 2.0.0, in those cases you can use TaskThreaded instead of TaskRQ; this way, each background task will run in it’s own thread.

MIGRATING FROM django-task 1.5.1 to 2.0.0

  • derive your queue-based tasks from TaskRQ instead of Task
  • or use TaskThreaded
  • get_jobclass() overridable replaces get_jobfunc()

1.7   Support Job class

Starting from version 0.3.0, some conveniences have been added:

  • The @job decorator for job functions is no more required, as now uses queue.enqueue() instead of jobfunc.delay(), and retrieves the queue name directly from the Task itself
  • each Task can set it’s own TASK_TIMEOUT value (expressed in seconds), that when provided overrides the default queue timeout
  • a new Job class has been provided to share suggested common logic before and after jobfunc execution; you can either override run() to implement a custom logic, or (in most cases) just supply your own execute() method, and optionally override on_complete() to execute cleanup actions after job completion;


class CountBeansJob(Job):

    def execute(job, task):
        num_beans = task.num_beans
        for i in range(0, num_beans):
            task.set_progress((i + 1) * 100 / num_beans, step=10)

    def on_complete(job, task):
        print('task "%s" completed with: %s' % (str(, task.status))
        # An more realistic example from a real project ...
        # if task.status != 'SUCCESS' or task.error_counter > 0:
        #    task.alarm = BaseTask.ALARM_STATUS_ALARMED
        #['alarm', ])


Run consumer:

python runserver

Run worker(s):

python rqworker low high default
python rqworker low high default

Sample Task

from django.db import models
from django.conf import settings
from django_task.models import TaskRQ

class SendEmailTask(TaskRQ):

    sender = models.CharField(max_length=256, null=False, blank=False)
    recipients = models.TextField(null=False, blank=False,
        help_text='put addresses in separate rows')
    subject = models.CharField(max_length=256, null=False, blank=False)
    message = models.TextField(null=False, blank=True)

    TASK_QUEUE = settings.QUEUE_LOW
    LOG_TO_FIELD = True
    LOG_TO_FILE = False

    def get_jobclass():
        from .jobs import SendEmailJob
        return SendEmailJob

You can change the verbosity dynamically by overridding the verbosity property:

class SendEmailTask(TaskRQ):

    def verbosity(self):
        #return self.DEFAULT_VERBOSITY
        return 1  # either 0, 1 or 2

When using LOG_TO_FILE = True, you might want to add a cleanup handler to remove the log file when the corresponding record is deleted:

import os
from django.dispatch import receiver

@receiver(models.signals.post_delete, sender=ImportaCantieriTask)
def on_sendemailtask_delete_cleanup(sender, instance, **kwargs):
    Autodelete logfile on Task delete
    logfile = instance._logfile()
    if os.path.isfile(logfile):

Sample Job

import redis
import logging
import traceback
from django.conf import settings
from .models import SendEmailTask
from django_task.job import Job

class SendEmailJob(Job):

    def execute(job, task):
        recipient_list = task.recipients.split()
        sender = task.sender.strip()
        subject = task.subject.strip()
        message = task.message
        from django.core.mail import send_mail
        send_mail(subject, message, sender, recipient_list)

Sample management command

from django_task.task_command import TaskCommand
from django.contrib.auth import get_user_model

class Command(TaskCommand):

    def add_arguments(self, parser):
        super(Command, self).add_arguments(parser)
        parser.add_argument('-r', '--recipients', nargs='*')
        parser.add_argument('-u', '--user', type=str, help="Specify username for 'created_by' task field")

    def handle(self, *args, **options):
        from tasks.models import SendEmailTask

        # transform the list of recipents into text
        # (one line for each recipient)
        options['recipients'] = '\n'.join(options['recipients']) if options['recipients'] is not None else ''

        # format multiline message
        options['message'] = options['message'].replace('\\n', '\n')

        if 'user' in options:
            created_by = get_user_model().objects.get(username=options['user'])
            created_by = None

        self.run_task(SendEmailTask, created_by=created_by, **options)

Deferred Task retrieval to avoid job vs. Task race condition

An helper Task.get_task_from_id() classmethod is supplied to retrieve Task object from task_id safely.

Task queues create a new type of race condition. Why ? Because message queues are fast ! How fast ? Faster than databases.


A similar generic helper is available for Job-derived needs:

django_task.utils.get_model_from_id(model_cls, id, timeout=1000, retry_count=10)

Howto separate jobs for different instances on the same machine

To sepatare jobs for different instances on the same machine (or more precisely for the same redis connection), override queues names for each instance;

for example:

# file ""

REDIS_URL = 'redis://localhost:6379/0'

# RQ config

RQ_PREFIX = "myproject_"

        'URL': REDIS_URL,
        #'PASSWORD': 'some-password',
        'DEFAULT_TIMEOUT': 360,
        'URL': REDIS_URL,
        'DEFAULT_TIMEOUT': 500,
    QUEUE_LOW: {
        'URL': REDIS_URL,
        #'ASYNC': False,

DJANGOTASK_LOG_ROOT = os.path.abspath(os.path.join(BASE_DIR, '..', 'protected', 'tasklog'))

then run worker as follows:

python rqworker myproject_default

Howto schedule jobs with cron

Call management command ‘count_beans’, which in turn executes the required job.

For example:


0 * * * *  {{username}}    timeout 55m {{django.pythonpath}}/python {{django.website_home}}/ count_beans 1000 >> {{django.logto}}/cron.log 2>&1

A base class TaskCommand has been provided to simplify the creation of any specific task-related management commad;

a derived management command is only responsible for:

  • defining suitable command-line parameters
  • selecting the specific Task class and job function

for example:

from django_task.task_command import TaskCommand

class Command(TaskCommand):

    def add_arguments(self, parser):
        super(Command, self).add_arguments(parser)
        parser.add_argument('num_beans', type=int)

    def handle(self, *args, **options):
        from tasks.models import CountBeansTask
        self.run_task(CountBeansTask, **options)

1.8   Javascript helpers

A few utility views have been supplied for interacting with tasks from javascript.

1.8.1   tasks_info_api

Retrieve informations about a list of existing tasks

Sample usage:

var tasks = [{
    id: 'c50bf040-a886-4aed-bf41-4ae794db0941',
    model: 'tasks.devicetesttask'
}, {
    id: 'e567c651-c8d5-4dc7-9cbf-860988f55022',
    model: 'tasks.devicetesttask'

    url: '/django_task/info/',
    data: JSON.stringify(tasks),
    cache: false,
    type: 'post',
    dataType: 'json',
    headers: {'X-CSRFToken': getCookie('csrftoken')}
}).done(function(data) {
    console.log('data: %o', data);


    "id": "c50bf040-a886-4aed-bf41-4ae794db0941",
    "created_on": "2018-10-11T17:45:14.399491+00:00",
    "created_on_display": "10/11/2018 19:45:14",
    "created_by": "4f943f0b-f5a3-4fd8-bb2e-451d2be107e2",
    "started_on": null,
    "started_on_display": "",
    "completed_on": null,
    "completed_on_display": "",
    "job_id": "",
    "status": "PENDING",
    "status_display": "<div class=\"task_status\" data-task-model=\"tasks.devicetesttask\" data-task-id=\"c50bf040-a886-4aed-bf41-4ae794db0941\" data-task-status=\"PENDING\" data-task-complete=\"0\">PENDING</div>",
    "log_link_display": "",
    "failure_reason": "",
    "progress": null,
    "progress_display": "-",
    "completed": false,
    "duration": null,
    "duration_display": "",
    "extra_fields": {

1.8.2   task_add_api

Create and run a new task based on specified parameters

Expected parameters:

  • ‘task-model’ = “<app_name>.<model_name>”
  • … task parameters …

Returns the id of the new task.

Sample usage:

function exportAcquisition(object_id) {
    if (confirm('Do you want to export data ?')) {

        var url = '/django_task/add/';
        var data = JSON.stringify({
            'task-model': 'tasks.exportdatatask',
            'source': 'backend.acquisition',
            'object_id': object_id

            type: 'POST',
            url: url,
            data: data,
            cache: false,
            crossDomain: true,
            dataType: 'json',
            headers: {'X-CSRFToken': getCookie('csrftoken')}
        }).done(function(data) {
            console.log('data: %o', data);
            alert('New task created: "' + data.task_id + '"');
        }).fail(function(jqXHR, textStatus, errorThrown) {
            console.log('ERROR: ' + jqXHR.responseText);

1.8.3   task_run_api

Schedule execution of specified task.

Returns or throws error (400).


  • app_label
  • model_name
  • pk
  • is_async (0 or 1, default=1)

Sample usage:

var task_id = 'c50bf040-a886-4aed-bf41-4ae794db0941';

    url: sprintf('/django_task/tasks/devicetesttask/%s/run/', task_id),
    cache: false,
    type: 'get'
}).done(function(data) {
    console.log('data: %o', data);
}).fail(function(jqXHR, textStatus, errorThrown) {

1.9   Updating the tasks listing dynamically in the frontend

The list of Tasks in the admin changelist_view is automatically updated to refresh the progess and status of each running Task.

You can obtain the same result in the frontend by calling the DjangoTask.update_tasks() javascript helper, provided you’re listing the tasks in an HTML table with a similar layout.

The simplest way to do it is to use the render_task_column_names_as_table_row and render_task_as_table_row template tags.


{% load i18n django_task_tags %}

{% if not export_data_tasks %}
    <div>{% trans 'No recent jobs available' %}</div>
{% else %}
    <table id="export_data_tasks" class="table table-striped">
        {% with excluded='created_by,created_on,job_id,log_text,mode' %}
                {{ export_data_tasks.0|render_task_column_names_as_table_row:excluded }}
            {% for task in export_data_tasks %}
                {{ task|render_task_as_table_row:excluded }}
            {% endfor %}
    {% endwith %}
{% endif %}

{% block extrajs %}
    {{ block.super }}
    <script type="text/javascript" src="{% static 'js/django_task.js' %}"></script>
        $(document).ready(function() {
            DjangoTask.update_tasks(1000, '#export_data_tasks');
{% endblock extrajs %}

For each fieldname included in the table rows, render_task_as_table_row will check if a FIELDNAME_display() method is available in the Task model, and in case will use it for rendering the field value; otherwise, the field value will be simply converted into a string.

If the specific derived Task model defines some additional fields (unknown to the base Task model) which need to be updated regularly by DjangoTask.update_tasks(), include them as “extra_fields” as follows:

def as_dict(self):
    data = super(ExportDataTask, self).as_dict()
    data['extra_fields'] = {
        'result_display': mark_safe(self.result_display())
    return data

1.10   Example Project for django-task

As example project is provided as a convenience feature to allow potential users to try the app straight from the app repo without having to create a django project.

Please follow the instructions detailed in file example/README.rst.

2   History

2.1   2.0.0

  • Split Task model into TaskBase + TaskRQ
  • Implement TaskThreaded
  • Drop Django1 and Python2.7
  • cleanup
  • Revamped unit tests
  • Simpler queues settings

2.2   1.5.1

  • Moved required imports inside so it can be more easily replicated for any needed customization
  • Simpler queues settings
  • Revamped unit testing
  • Cleanup

2.3   1.5.0

  • Support for updating the tasks listing dynamically in the frontend
  • Example provided for task_add_api() javascript helper
  • POSSIBLY INCOMPATIBLE CHANGE: duration and duration_display are now methods rather then properties
  • it traslation for UI messages

2.4   1.4.7

  • Added optional “created_by” parameter to TaskCommand utility

2.5   1.4.6

  • replace namespace “django.jQuery” with more generic “jQuery” in js helpers
  • update example project
  • unit tests added to “tasks” app in example project

2.6   1.4.5

  • Quickstart revised in README

2.7   1.4.4

  • Task.get_logger() is now publicly available

2.8   1.4.3

  • restore compatibility with Django 1.11; upgrade rq and django-rq requirements

2.9   1.4.2

  • tasks_info_api() optimized to use a single query

2.10   1.4.1

  • Cleanup: remove redundant REJECTED status

2.11   1.4.0

  • Update requirements (Django >= 2.0, django-rq>=2.0)

2.12   1.3.10

  • Use exceptions.TaskError class when raising specific exceptions

2.13   v1.3.9

  • removed forgotten pdb.set_trace() in revoke_pending_tasks()

2.16   v1.3.6

  • log queue name

2.17   v1.3.5

  • Readme updated

2.18   v1.3.4

  • javascript helper views
  • fix Task.set_progress(0)

2.19   v1.3.3

  • make sure fields are unique in TaskAdmin fieldsets

2.20   v1.3.1

  • unit tests verified with Python 2.7/3.6/3.7 and Django 1.10/2.0

2.21   v1.3.0

  • cleanup
  • classify as production/stable

2.22   v1.2.5

  • Tested with Django 2.0 and Python 3.7
  • Rename async to is_async to support Python 3.7
  • example cleanup

2.23   v1.2.4

  • API to create and run task via ajax

2.24   v1.2.3

  • TaskAdmin: postpone autorun to response_add() to have M2M task parameters (if any) ready
  • Task.clone() supports M2M parameters

2.25   v1.2.2

  • property to change verbosity dinamically

2.26   v1.2.1

  • util revoke_pending_tasks() added

2.27   v1.2.0

  • DJANGOTASK_JOB_TRACE_ENABLED setting added to enable low level tracing in
  • Added missing import in

2.28   v1.1.3

  • cleanup: remove get_child() method being Task an abstract class
  • fix: skip Task model (being abstract) in dump_all_tasks and delete_all_tasks management commands
  • generic get_model_from_id() helper
  • Job.on_complete() callback

2.29   v1.1.2

  • provide list of pending and completed task status

2.30   v1.1.0

  • INCOMPATIBLE CHANGE: Make model Task abstract for better listing performances
  • redundant migrations removed
  • convert request.body to string for Python3
  • pretty print task params in log when task completes

2.31   v0.3.8

  • return verbose name as description

2.32   v0.3.7

  • description added to Task model

2.33   v0.3.6

  • More fixes

2.34   v0.3.5

  • log to field fix

2.35   v0.3.4

  • log quickview + view

2.36   v0.3.3

  • Optionally log to either file or text field
  • Management commands to dump and delete all tasks

2.37   v0.3.2

  • search by and task.job_id

2.38   v0.3.1

  • Keep track of task mode (sync or async)

2.39   v0.3.0

  • new class Job provided to share task-related logic among job funcs

2.40   v0.2.0

  • fixes for django 2.x

2.41   v0.1.15

  • hack for prepopulated_fields

2.43   v0.1.13

  • minor fixes

2.44   v0.1.12

  • Deferred Task retrieval to avoid job vs. Task race condition
  • Improved Readme

2.45   v0.1.11

  • superuser can view all tasks, while other users have access to their own tasks only
  • js fix

2.46   v0.1.10

  • prevent task.failure_reason overflow

2.47   v0.1.9

  • app settings

2.48   v0.1.8

  • always start job from to prevent any possible race condition
  • can now accept async=False

2.49   v0.1.7

  • javascript: use POST to retrieve tasks state for UI update to prevent URL length limit exceed

2.50   v0.1.6

  • Improved ui for TaskAdmin
  • Fix unicode literals for Python3

2.51   v0.1.5

  • fixes for Django 1.10
  • send_email management command example added

2.52   v0.1.4

  • Fix OneToOneRel import for Django < 1.9

2.53   v0.1.3

  • Polymorphic behaviour or Task.get_child() restored

2.54   v0.1.2

  • TaskCommand.run_task() renamed as TaskCommand.run_job()
  • New TaskCommand.run_task() creates a Task, then runs it; this guarantees that something is traced even when background job will fail

Project details

Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Files for django-task, version 2.0.0
Filename, size File type Python version Upload date Hashes
Filename, size django_task-2.0.0-py2.py3-none-any.whl (42.3 kB) File type Wheel Python version py2.py3 Upload date Hashes View

Supported by

AWS AWS Cloud computing Datadog Datadog Monitoring DigiCert DigiCert EV certificate Facebook / Instagram Facebook / Instagram PSF Sponsor Fastly Fastly CDN Google Google Object Storage and Download Analytics Microsoft Microsoft PSF Sponsor Pingdom Pingdom Monitoring Salesforce Salesforce PSF Sponsor Sentry Sentry Error logging StatusPage StatusPage Status page