Plugins

Beginning with version 3.0, Pelican supports plugins. Plugins are a way to add features to Pelican without having to directly modify the Pelican core.

How to use plugins

To load plugins, you have to specify them in your settings file. There are two ways to do so. The first method is to specify strings with the path to the callables:

PLUGINS = ['package.myplugin',]

Alternatively, another method is to import them and add them to the list:

from package import myplugin
PLUGINS = [myplugin,]

If your plugins are not in an importable path, you can specify a PLUGIN_PATH in the settings. PLUGIN_PATH can be an absolute path or a path relative to the settings file:

PLUGIN_PATH = "plugins"
PLUGINS = ["list", "of", "plugins"]

Where to find plugins

We maintain a separate repository of plugins for people to share and use. Please visit the pelican-plugins repository for a list of available plugins.

Please note that while we do our best to review and maintain these plugins, they are submitted by the Pelican community and thus may have varying levels of support and interoperability.

How to create plugins

Plugins are based on the concept of signals. Pelican sends signals, and plugins subscribe to those signals. The list of signals are defined in a subsequent section.

The only rule to follow for plugins is to define a register callable, in which you map the signals to your plugin logic. Let’s take a simple example:

from pelican import signals

def test(sender):
    print "%s initialized !!" % sender

def register():
    signals.initialized.connect(test)

List of signals

Here is the list of currently implemented signals:

Signal	Arguments	Description
initialized	pelican object
finalized	pelican object	invoked after all the generators are executed and just before pelican exits usefull for custom post processing actions, such as: - minifying js/css assets. - notify/ping search engines with an updated sitemap.
generator_init	generator	invoked in the Generator.__init__
article_generate_context	article_generator, metadata
article_generate_preread	article_generator	invoked before a article is read in ArticlesGenerator.generate_context; use if code needs to do something before every article is parsed
article_generator_init	article_generator	invoked in the ArticlesGenerator.__init__
article_generator_finalized	article_generator	invoked at the end of ArticlesGenerator.generate_context
get_generators	generators	invoked in Pelican.get_generator_classes, can return a Generator, or several generator in a tuple or in a list.
pages_generate_context	pages_generator, metadata
pages_generator_init	pages_generator	invoked in the PagesGenerator.__init__
pages_generator_finalized	pages_generator	invoked at the end of PagesGenerator.generate_context
content_object_init	content_object	invoked at the end of Content.__init__ (see note below)

The list is currently small, so don’t hesitate to add signals and make a pull request if you need them!

Note

The signal content_object_init can send a different type of object as the argument. If you want to register only one type of object then you will need to specify the sender when you are connecting to the signal.

from pelican import signals
from pelican import contents

def test(sender, instance):
        print "%s : %s content initialized !!" % (sender, instance)

def register():
        signals.content_object_init.connect(test, sender=contents.Article)