Add URL redirector for http://postgr.es/p/<id>

Not used yet, need to deploy the redirector before it can be used..
mhagander · Mar 28, 2011 · f4a0cef · f4a0cef
1 parent e158d6a
commit f4a0cef
Showing 1 changed file with 78 additions and 0 deletions.
diff --git a/redirector/redirector.py b/redirector/redirector.py
@@ -0,0 +1,78 @@
+#!/usr/bin/env python
+"""PostgreSQL Planet Aggregator
+
+This is a FastCGI implementation of the planet URL redirector.
+
+Accepts URLs like /p/<shorturl> and sends a redirect to the proper
+URL for the post requested.
+
+Copyright (C) 2011 PostgreSQL Global Development Group
+"""
+
+import ConfigParser
+import psycopg2
+from flup.server.fcgi import WSGIServer
+
+# Simple map used to shorten id values to URLs
+_urlvalmap = ['0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', '-', '_']
+
+connstr = ""
+
+def iddecode(idstr):
+	idval = 0
+	for c in idstr:
+		idval *= 64
+		idval += _urlvalmap.index(c)
+	return idval
+
+def redirapp(environ, start_response):
+	try:
+		# Start by getting the id from the request
+		id = iddecode(environ['PATH_INFO'].split('/')[-1])
+
+		# Let's figure out where this URL should be
+
+		# Since we cache heavily with varnish in front of this, we don't
+		# bother with any connection pooling.
+		conn = psycopg2.connect(connstr)
+		c = conn.cursor()
+		c.execute("SELECT link FROM planet.posts WHERE id=%(id)s", {
+				'id': id
+				})
+		r = c.fetchall()
+
+		conn.close()
+
+		if len(r) != 1:
+			start_response('404 Not Found', [
+					('Content-type', 'text/plain'),
+					])
+			return ["Link not found\n"]
+
+		# We have a link, return a redirect to it
+		start_response('301 Moved Permanently', [
+				('Content-type', 'text/html'),
+				('Location', r[0][0]),
+				('X-Planet', str(id))
+				])
+		return [
+			"<html>\n<head>\n<title>postgr.es</title>\n</head>\n<body>\n",
+			"<a href=\"%s\">moved here</a>\n" % r[0][0],
+			"</body>\n</html>\n"
+			]
+	except Exception, ex:
+		start_response('500 Internal Server Error', [
+				('Content-type', 'text/plain')
+				])
+
+		return [
+			"An internal server error occured\n",
+			str(ex)
+			]
+
+
+if __name__ == '__main__':
+	c = ConfigParser.ConfigParser()
+	c.read('redir.ini')
+	connstr = c.get('planet', 'db')
+	WSGIServer(redirapp).run()