# General Use

1. A lisp file should be created in coleslaw's ```plugins``` directory.
2. Any necessary lisp libraries not loaded by coleslaw should be included like so:

    ```(eval-when (:compile-toplevel :load-toplevel) (ql:quickload '(foo bar)))```

3. A package should be created for the plugin code like so:

    ```(defpackage :coleslaw-$NAME (:use :cl) (:export #:enable) ...)```

    where $NAME is the pathname-name of the lisp file. (eg. `:coleslaw-disqus` for `disqus.lisp`)
4. An enable function should be present even if it's a no-op. Any work to enable the plugin is done there.


# Extension Points

* **New functionality via JS**, for example the Disqus and Mathjax
  plugins. In this case, the plugin's `enable` function should call
  [`add-injection`](http://redlinernotes.com/docs/coleslaw.html#add-injection_func)
  with an injection and a keyword. The injection itself is a list of
  the string to insert and a lambda or function that can be called on
  a content instance to determine whether the injection should be
  included on the page. The keyword specifies whether the injected
  text goes in the HEAD or BODY element. The
  [Disqus plugin](http://github.com/redline6561/coleslaw/blob/master/plugins/disqus.lisp)
  is a good example of this.

* **New markup formats**, for example the
  [ReStructuredText plugin](http://github.com/redline6561/coleslaw/blob/master/plugins/rst.lisp),
  can be created by definining an appropriate `render-text`
  method. The method takes `text` and `format` arguments and is
  [EQL-specialized](http://www.gigamonkeys.com/book/object-reorientation-generic-functions.html#defmethod)
  on the format. Format should be a keyword matching the file
  extension (or `pathname-type`) of the markup format.
  (eg. `:rst` for ReStructuredText)

* **New hosting options**, for example the
  [Amazon S3 plugin](http://github.com/redline6561/coleslaw/blob/master/plugins/s3.lisp),
  can be created by definining a `deploy :after` method. The method
  takes a staging directory, likely uninteresting in the `:after`
  stage. But by importing `*config*` from the coleslaw package and
  getting its deploy location with `(deploy-dir *config*)` a number of
  interesting options become possible.

* **New content types**, for example the
  [static page content type](http://github.com/redline6561/coleslaw/blob/master/plugins/static-pages.lisp),
  can be created by definining a subclass of CONTENT along with a
  template, and `render`, `page-url`, and `publish` methods.
  The PAGE content type cheats a bit by reusing the existing POST template.

* **New service integrations**, for example crossposting to
  twitter/facebook/tumblr/livejournal/etc, should also be possible by
  adding an :after hook to the deploy method as with
  hosting but this is dependent on knowing which posts are new
  which should become possible before 1.0. See the incremental compilation
  notes in the hacking docs for further details.