Cryogen customization: autolink headings etc.

blog.scss

#post a.anchor, #custom-page a.anchor {
  float: left;
  padding-right: 4px;
  margin-left: -20px;
}

core.clj

;; http://cryogenweb.org/ customization that adds self-links to
;; all headings, GitHub-style
;; Version: cryogen-core "0.2.3"
(ns cryogen.core
  (:require [cryogen-core.compiler :refer [compile-assets-timed]]
            [cryogen-core.plugins :refer [load-plugins]]
            [net.cgrand.enlive-html :as enlive])
  (:import (java.io StringReader)))

;;------------------------------------------------------------ autolink-headings

(defn permalink-node [{{heading-id :id} :attrs :as heading} blog-prefix]
  (first
    (enlive/html
      [:a {:href (str "#" heading-id)
           :aria-label (str "Permalink to " (enlive/text heading))
           :class "anchor"}
       [:svg {:aria-hidden true :focusable false :width 16 :height 16}
        [:use {:xlink:href (str blog-prefix "/img/icons.svg#icon-link")}]]])))

(defn autolink-content-headings [content-nodes blog-prefix]
  (-> content-nodes
      (enlive/transform
        [#{:h1 :h2 :h3 :h4 :h5 :h6}]
        (fn autolink-heading [heading]
          (update heading
                  :content
                  #(apply vector (permalink-node heading blog-prefix) %))))))

(defn autolink-headings [article {:keys [blog-prefix]}]
  (update article :content-dom autolink-content-headings blog-prefix))

;;---------------------------------------------------------------------

(defn compile-site []
  (compile-assets-timed
    {:update-article-fn ; NOTE You may want to have a look at :postprocess-article-html-fn instead 
     (fn update-article [article config]
       ;; Skip articles with `:ignore? true` in metadata
       (when-not (:ignore? article)
         (autolink-headings article config)))}))

(defn -main []
  (load-plugins)
  (compile-site)
  (System/exit 0))

icons.svg

There's a couple places in cryogen.server where compile-assets-timed gets called that should be replaced by compile-site as well if you actually want to see the customization while running your blog locally 😛

For users of newer cryogen versions: Replace :update-article-fn with :postprocess-article-html-fn, this way it keeps working.

Thank you both!

@JohnnyJayJay actually :update-article-fn still works, it only needed to be updated to (update article :content-dom ...) (instead of :cintent) and autolink-content-headings had to be changed to simply return the output of enlive/transform. Here is live, working code from my blog.

Notice that postprocess-article-html-fn receives the HTML, while update-article-fn can use the parsed DOM nodes in content-dom, which is better for Enlive - you do not need to re-parse the text.

Yeah, I did the same for my use of this code. The change I suggested in this comment is just the "minimal change" that was necessary to keep it working