Backend App Development

This document details instructions and guidelines for developing backend apps to be used with the SODAR Core framework.

It is recommended to read Project App Development before this document.

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Backend App Basics

Backend apps are intended as apps used by other apps via their plugin, without requiring hard-coded imports. These may provide their own views for e.g. Ajax API functionality, but mostly they’re intended to be internal (hence the name).

Prerequisites

See Project App Development.

Models

No specific model implementation is required. However, it is strongly to refer to objects using sodar_uuid fields instead of the database private key.

BackendAppPlugin

The plugin is detected and retrieved using a BackendAppPlugin.

Declaring the Plugin

Create a file plugins.py in your app’s directory. In the file, declare a BackendAppPlugin class implementing projectroles.plugins.BackendPluginPoint. Within the class, implement member variables and functions as instructed in comments and docstrings.

from projectroles.plugins import BackendPluginPoint
from .urls import urlpatterns

class BackendAppPlugin(BackendPluginPoint):
    """Plugin for registering a backend app"""
    name = 'example_backend_app'
    title = 'Example Backend App'
    urls = urlpatterns
    # ...

The following variables and functions are mandatory:

• name: App name (ideally should correspond to the app package name)
• title: Printable app title
• icon: Font Awesome 4.7 icon name (without the fa-* prefix)
• description: Verbose description of app
• get_api(): Function for retrieving the API class for the backend, to be implemented

Implementing the following is optional:

• get_statistics(): Return statistics for the siteinfo app. See details in the siteinfo documentation.

Hint

If you want to implement a backend API which is closely tied to a project app, there’s no requirement to declare your backend as a separate Django app. You can just include the BackendAppPlugin in your app’s plugins.py along with your ProjectAppPlugin. See the timeline app for an example of this.

Using the Plugin

To retrieve the API for the plugin, use the function projectroles.plugins.get_backend_api() as follows:

from projectroles.plugins import get_backend_api
example_api = get_backend_api('example_backend_app')

if example_api:     # Make sure the API is there, and only after that..
    pass            # ..do stuff with the API