added dm2twitter which posts DMs to Twitter

dm2twitter.rb

@@ -0,0 +1,57 @@
+#!/usr/bin/env ruby
+
+require "twitter"
+
+# dm2twitter.rb looks up the latest direct messages and posts
+# them as a update if the sender was in the whitelist.
+#
+# Licence: BSD
+# Author: Jeena Paradies <spam@jeenaparadies.net>
+# 
+#
+# You could use it with Postfix and add to /etc/aliases
+# myuser: myuser, "|/home/myuser/scripts/sender.sh"
+#
+# Or you could run it with help of a crontab every couple
+# of minutes.
+
+# Change this:
+USERNAME = "myusername"
+PASSWORD = "mypassword"
+
+SENDER_WHITELIST = %w(someuser otheruser thirduser)
+
+# If you already have DMs which you don't want to post
+# create a new file with just the last ID number of the
+# unwanted DMs.
+LASTID_PATH = "dm2twitter-lastid.txt"
+
+
+#
+# Do not change this
+#
+client = Twitter::Base.new(Twitter::HTTPAuth.new(USERNAME, PASSWORD))
+
+lastid = nil
+lastid = File.read(LASTID_PATH).to_i if File.writable? LASTID_PATH
+
+client.direct_messages(:since_id => lastid).each do |message|
+  
+  if SENDER_WHITELIST.include? message["sender_screen_name"]
+    
+    via = " (via #{message["sender_screen_name"]})"
+    update_text = message["text"] + via
+    
+    unless update_text.length > 140
+      client.update(update_text)
+      File.open(LASTID_PATH, 'w') { |f| f.write(message["id"]) }
+    else
+      client.direct_message_create(
+        message["sender_screen_name"],
+        "Sorry your message was too long, was: #{update_text.length} chars, should be: #{140 - via.length} chars."
+      )
+    end
+
+  end
+  
+end