[bknr-cvs] hans changed trunk/projects/planetwit/planetwit.clj

[BKNR Commits]

Revision: 4444
Author: hans
URL: http://bknr.net/trac/changeset/4444

comments, rename some functions
U   trunk/projects/planetwit/planetwit.clj

Modified: trunk/projects/planetwit/planetwit.clj
===================================================================
--- trunk/projects/planetwit/planetwit.clj	2009-08-20 00:56:01 UTC (rev 4443)
+++ trunk/projects/planetwit/planetwit.clj	2009-08-20 11:44:49 UTC (rev 4444)
@@ -1,3 +1,14 @@
+;;; planet.lisp.org -> twitter gateway
+;;;
+;;; Copyright 2008/2009 Hans Huebner
+
+;;; Generate a twitter status update with the item title and the
+;;; permalink URL shortened by tinyurl.com for each new item posted to
+;;; planet.lisp.org.
+
+;;; The guids of all items that has been forwarded to twitter are
+;;; stored as a literal set in the text file +state-file+.
+
 (ns planetwit
   (:require [clojure.zip :as zip]
             [clojure.xml :as xml])
@@ -23,10 +34,10 @@
 (defn write-file [data file-name]
   (spit file-name (with-out-str (pr data))))
 
-(defn load-data []
+(defn load-data-from-file []
   (read-file +state-file+ #{}))
 
-(defn save-data [data]
+(defn save-data-to-file [data]
   (write-file data +state-file+))
 
 (defn feed-to-zip [url]
@@ -42,7 +53,11 @@
    (catch java.io.FileNotFoundException _
      (println (format "could not update twitter status (no auth file):\n%s\n" status)))))
 
-(defn post-twits [items]
+(defn post-twits
+  "Given a list of new item hashes in ITEMS, send a twitter status
+  update for each of them consisting of the :title string and a tiny
+  URL pointing to the item itself."
+  [items]
   (when items
     (let [item (first items)]
       (update-twitter-status
@@ -54,16 +69,23 @@
                        nil))))
       (recur (rest items)))))
 
+(defn load-feed
+  "Load planet.lisp.org feed, return a hash for every item containing
+  the item permalink under the :guid key and the item's title under
+  the :title key"
+  []
+  (map (fn [item]
+         {:guid (first (xml-> item :guid text))
+          :title (first (xml-> item :title text))})
+       (xml-> (feed-to-zip "http://planet.lisp.org/rss20.xml")
+              :channel :item)))
+
 (defn poll
   "Poll planet lisp, check for new postings, update Twitter status when new postings have appeared"
   []
-   (let [old-urls (load-data)
-         all-items (map (fn [item]
-                          {:guid (first (xml-> item :guid text))
-                           :title (first (xml-> item :title text))})
-                        (xml-> (feed-to-zip "http://planet.lisp.org/rss20.xml")
-                               :channel :item))
+   (let [old-urls (load-data-from-file)
+         all-items (load-feed)
          new-items (filter (complement #(old-urls (:guid %))) all-items)]
      (post-twits new-items)
-     (save-data (into #{} (map #(:guid %) all-items)))))
+     (save-data-to-file (into #{} (map #(:guid %) all-items)))))