From 03cfabcbb903845babee774f699cb6004dc03731 Mon Sep 17 00:00:00 2001
From: Randall Mason <randall@mason.ch>
Date: Thu, 3 Sep 2015 11:27:55 -0500
Subject: [PATCH] Add enclosure tag to facilitate Podcasting with Cryogen

Add an enclosure tag to a post's metadata to let a podcast client
to deliver your audio content.  It should look like this:

:enclosure [{:url "<full-url>"}]

Without the brackets, you end up with NullPointerExceptions, so
make sure you have that.

The URL should be the full location of where the audio file is
hosted (not relative), so for example:

:enclosure [{:url "http://www.example.com/01_episode_IV.mp3"}]

I created a bunch of markdown files with just the enclosure and
info about the audiobook with the following bash snippet:

find -L books -type f -iname "*mp3" | sort | while read mp3; do name=$(basename $mp3 .mp3); book=$(basename "$(dirname $mp3)"); echo "{:title \"$name\"\n:layout :post\n:tags [\"audiobooks\" \"$book\"]\n:enclosure [{:url \"http://clashthebunny.mason.ch/blog/$mp3\"}]}\n $book - $name\n==================" > md/posts/"$(date "+%Y-$name").md"; done

Each book was in it's own subdirectory of books:
books/Dracula/1-01-Chapter1_part01.mp3
books/Dracula/1-02-Chapter1_part02.mp3
books/Dracula/2-01-Chapter2_part01.mp3

Note that the above script requires the prefix of the episode to
be "date-like".  It should be fairly easy to work out a way to get
your podcast up and running.

Add the book names to your rss-filters array, e.g.:
["Dracula" "Pride & Prejudice"]

Most podcasting clients support authentication, so just password
protect those directories and you should be good to go, even
if you are hosting copyrighted content.
---
 src/cryogen_core/compiler.clj | 2 +-
 src/cryogen_core/rss.clj      | 7 ++++---
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/src/cryogen_core/compiler.clj b/src/cryogen_core/compiler.clj
index 06e867c..426b011 100644
--- a/src/cryogen_core/compiler.clj
+++ b/src/cryogen_core/compiler.clj
@@ -143,7 +143,7 @@
   "Adds the uri and title of a post to the list of posts under each of its tags"
   [tags post]
   (reduce (fn [tags tag]
-            (update-in tags [tag] (fnil conj []) (select-keys post [:uri :title :content :date])))
+            (update-in tags [tag] (fnil conj []) (select-keys post [:uri :title :content :date :enclosure])))
           tags (:tags post)))
 
 (defn group-by-tags
diff --git a/src/cryogen_core/rss.clj b/src/cryogen_core/rss.clj
index 8aa6e44..38c8ec8 100644
--- a/src/cryogen_core/rss.clj
+++ b/src/cryogen_core/rss.clj
@@ -1,18 +1,19 @@
 (ns cryogen-core.rss
   (:require [clj-rss.core :as rss]
-            [clojure.xml :refer [emit]]
             [text-decoration.core :refer :all])
   (:import java.util.Date))
 
 
 (defn posts-to-items [site-url posts]
   (map
-    (fn [{:keys [uri title content date]}]
-      (let [link (str (if (.endsWith site-url "/") (apply str (butlast site-url)) site-url) uri)]
+    (fn [{:keys [uri title content date enclosure]}]
+      (let [link (str (if (.endsWith site-url "/") (apply str (butlast site-url)) site-url) uri)
+            enclosure (if (nil? enclosure) "" enclosure)]
         {:guid        link
          :link        link
          :title       title
          :description content
+         :enclosure   enclosure
          :pubDate     date}))
     posts))