blog/data/2012-12-06-bofhd-scripting.txt

   1 Title: Scripting the Cerebrum/bofhd user administration system using XML-RPC
   2 Tags: english, sysadmin
   3 Date: 2012-12-06 10:30
   4
   5 <p>Where I work at the <a href="http://www.uio.no/">University of
   6 Oslo</a>, we use the
   7 <a href="http://sourceforge.net/projects/cerebrum/">Cerebrum user
   8 administration system</a> to maintain users, groups, DNS, DHCP, etc.
   9 I've known since the system was written that the server is providing
  10 an <a href="http://en.wikipedia.org/wiki/XML-RPC">XML-RPC</a> API, but
  11 I have never spent time to try to figure out how to use it, as we
  12 always use the bofh command line client at work.  Until today.  I want
  13 to script the updating of DNS and DHCP to make it easier to set up
  14 virtual machines.  Here are a few notes on how to use it with
  15 Python.</p>
  16
  17 <p>I started by looking at the source of the Java
  18 <a href="http://cerebrum.svn.sourceforge.net/viewvc/cerebrum/trunk/cerebrum/clients/jbofh/">bofh
  19 client</a>, to figure out how it connected to the API server.  I also
  20 googled for python examples on how to use XML-RPC, and found
  21 <a href="http://tldp.org/HOWTO/XML-RPC-HOWTO/xmlrpc-howto-python.html">a
  22 simple example in</a> the XML-RPC howto.</p>
  23
  24 <p>This simple example code show how to connect, get the list of
  25 commands (as a JSON dump), and how to get the information about the
  26 user currently logged in:</p>
  27
  28 <blockquote><pre>
  29 #!/usr/bin/env python
  30 import getpass
  31 import xmlrpclib
  32 server_url = 'https://cerebrum-uio.uio.no:8000';
  33 username = getpass.getuser()
  34 password = getpass.getpass()
  35 server = xmlrpclib.Server(server_url);
  36 #print server.get_commands(sessionid)
  37 sessionid = server.login(username, password)
  38 print server.run_command(sessionid, "user_info", username)
  39 result = server.logout(sessionid)
  40 print result
  41 </pre></blockquote>
  42
  43 <p>Armed with this knowledge I can now move forward and script the DNS
  44 and DHCP updates I wanted to do.</p>