-#!/usr/bin/env python2.5
+#!/usr/bin/python
"""
Collates the results of listvms from multiple VM servers. Part of the xvm
suite.
"""
-from itertools import chain
-from subprocess import CalledProcessError, PIPE, Popen
-from sys import argv, stdout
-from yaml import safe_dump, safe_load
+from subprocess import PIPE, Popen
+try:
+ from subprocess import CalledProcessError
+except ImportError:
+ # Python 2.4 doesn't implement CalledProcessError
+ class CalledProcessError(Exception):
+ """This exception is raised when a process run by check_call() returns
+ a non-zero exit status. The exit status will be stored in the
+ returncode attribute."""
+ def __init__(self, returncode, cmd):
+ self.returncode = returncode
+ self.cmd = cmd
+ def __str__(self):
+ return "Command '%s' returned non-zero exit status %d" % (self.cmd, self.returncode)
+import sys
+import yaml
###
-def run(cmd):
- """
- Run the given command (a list of program and argument strings) and return the
- stdout as a string, raising a CalledProcessError if the program exited with a
- non-zero status.
- """
- p = Popen(cmd, stdout=PIPE)
- stdout = p.communicate()[0]
- if p.returncode != 0: raise CalledProcessError(p.returncode, cmd)
- return stdout
-
def main(argv):
- # Query each of the server for their VMs.
- # TODO get `servers` from a real list of all the VM hosts (instead of
- # hardcoding the list here)
- servers = [ 'black-mesa.mit.edu', 'sx-blade-2.mit.edu' ]
- # XXX
- results = [ safe_load(run(['remctl', server, 'remote', 'web', 'listvms']))
- for server in servers ]
- results = filter( lambda x: x is not None, results )
-
- # Merge the results and print.
- merged = {}
- for result in results: merged.update(result)
- print safe_dump(merged, default_flow_style=False)
+ # Query each of the server for their VMs.
+ # TODO get `servers` from a real list of all the VM hosts (instead of
+ # hardcoding the list here)
+ servers = ['black-mesa.mit.edu', 'sx-blade-2.mit.edu']
+ # XXX
+ pipes = [Popen(['remctl', server, 'remote', 'web', 'listvms'], stdout=PIPE)
+ for server in servers]
+ outputs = [p.communicate()[0] for p in pipes]
+ for p in pipes:
+ if p.returncode != 0:
+ raise CalledProcessError(p.returncode, 'remctl')
+ results = [yaml.load(o, yaml.CSafeLoader) for o in outputs]
+ results = filter(lambda x: x is not None, results)
+
+ # Merge the results and print.
+ merged = {}
+ for result in results:
+ merged.update(result)
+
+ print yaml.dump(merged, Dumper=yaml.CSafeDumper, default_flow_style=False)
if __name__ == '__main__':
- main(argv)
+ main(sys.argv)
-# vim:et:sw=2:ts=2
+# vim:et:sw=4:ts=4