Package: modelqueue
ModelQueueis an Apache2 licensed task queue based on Django models.For example, in appname/models.py:import modelqueue
from django.db import models

class Task(models.Model):
    data = models.TextField()
    status = modelqueue.StatusField(
        # ^-- Just a models.BigIntegerField
        db_index=True,
        # ^-- Index for faster queries.
        default=modelqueue.Status.waiting,
        # ^-- Waiting state is ready to run.
    )And in appname/management/commands/process_tasks.py:import modelqueue, time
from django.core.management.base import BaseCommand
from .models import Task

class Command(BaseCommand):

    def handle(self, *args, **options):
        while True:
            task = modelqueue.run(
                Task.objects.all(),
                # ^-- Queryset of models to process.
                'status',
                # ^-- Field name for model queue.
                self.process,
                # ^-- Callable to process model.
            )
            if task is None:
                time.sleep(1)
                # ^-- Bring your own parallelism/concurrency.

    def process(self, task):
        pass  # Process task models.And in appname/admin.py:class TaskAdmin(admin.ModelAdmin):
    actions = [*modelqueue.admin_actions('status')]
    # ^-- Change task status in admin.
    list_filter = [
        modelqueue.admin_list_filter('status'),
        # ^-- Filter tasks in admin by queue state.
    ]

    def get_changeform_initial_data(self, request):
        # v-- Automatically fill in status field when adding a new task.
        return {'status': int(modelqueue.Status.waiting())}ModelQueueis a hazardous project. It takes a bad idea and makes it easy and
effective. You may come to regret using your database as a task queue but it
won’t be today!Testimonials“I didn’t design relational database systems for this.” ~Edgar Codd“Well, at least you’re using transactions.” ~Jim Gray“You have successfully ignored most of what’s important in queueing theory.” ~Agner ErlangDoes your company or website useModelQueue? Send us amessageand let us know.FeaturesPure-PythonSupports Django’s admin interfaceTasks can be retried, aborted, and canceledSupports multiple attempts per taskBring your own parallelism with threading, multiprocessing, or asyncioPerformance matters (add a single 64-bit field to models)Fully documented100% test coverageYears of stress testing in productionDeveloped on Python 3.10Compatible with all Django versionsTested on CPython 3.6, 3.7, 3.8, 3.9, 3.10Tested on Linux, Mac OS X, and WindowsQuickstartInstallingModelQueueis simple withpip:$ python -m pip install modelqueueYou can access documentation in the interpreter with Python’s built-in help
function:>>> import modelqueue
>>> help(modelqueue)User GuideFor those wanting more details, this part of the documentation describes
introduction, benchmarks, development, and API.ModelQueue API ReferenceReference and IndicesModelQueue DocumentationModelQueue at PyPIModelQueue at GitHubModelQueue Issue TrackerModelQueue LicenseCopyright 2022 Grant JenksLicensed under the Apache License, Version 2.0 (the “License”);
you may not use this file except in compliance with the License.
You may obtain a copy of the License athttp://www.apache.org/licenses/LICENSE-2.0Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an “AS IS” BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.