Architecture and Deploying

Pulp’s architecture has three components to it: a REST API, a content serving application, and the tasking system. Each component can be horizontally scaled for both high availability and/or additional capacity for that part of the architecture.

REST API

Pulp’s REST API is a Django application which runs under any WSGI server. It serves the following things:

  • The REST API hosted at /pulp/api/v3/

  • The browse-able documentation at /pulp/api/v3/docs/

  • Any viewsets or views provided by plugins

  • Static content used by Django, e.g. images used by the browse-able API. This is not Pulp content.

Note

A simple, but limited way to run the REST API as a standalone service using the built-in Django runserver.:

$ python django-admin runserver 24817

The REST API can be deployed with any any WSGI webserver like a normal Django application. See the Django deployment docs for more information.

Content Serving Application

An aiohttp.server based application that serves content to clients. The content could be Artifacts already downloaded and saved in Pulp, or on-demand content units. When serving on-demand content units the downloading also happens from within this component as well.

Note

Pulp installs a script that lets you run the content serving app as a standalone service as follows::

$ pulp-content

The content serving application can be deployed like any aiohttp.server application. See the aiohttp Deployment docs for more information.

Tasking System

Pulp’s tasking system has two components: a resource manager and workers, all of which are run using rq.

Worker

Pulp workers perform most tasks “run” by the tasking system including long-running tasks like synchronize and short-running tasks like a Distribution update. Each worker handles one task at a time, and additional workers provide more concurrency.

Resource Manager

A different type of Pulp worker that plays a coordinating role for the tasking system. You must run exactly one of these for Pulp to operate correctly.

Note

Pulp serializes tasks that are unsafe to run in parallel, e.g. a sync and publish operation on the same repo should not run in parallel. Generally tasks are serialized at the “repo” level, so if you have N workers you can process N repo sync’s concurrently.

Static Content

When browsing the REST API or the browsable documentation with a web browser, for a good experience, you’ll need static content to be served.

In Development

If using the built-in Django webserver and your settings.yaml has DEBUG: True then static content is automatically served for you.

In Production

For production environments, configure static content as follows:

Collect all of the static content into place using the collectstatic command as follows:

$ django-admin collectstatic