Bug 1276896

Description of problem:
When trying to use koan, it fails with an error:

expected version format differs
  File "/usr/lib/python2.7/site-packages/koan/app.py", line 274, in main
    k.run()
   File "/usr/lib/python2.7/site-packages/koan/app.py", line 424, in run
    self.virt()
   File "/usr/lib/python2.7/site-packages/koan/app.py", line 845, in virt
    return self.net_install(after_download)
   File "/usr/lib/python2.7/site-packages/koan/app.py", line 637, in net_install
    if len(version_str) == 0 and not utils.check_version_greater_or_equal(version_str.strip(), "0.2.0"):
   File "/usr/lib/python2.7/site-packages/koan/utils.py", line 592, in check_version_greater_or_equal
    raise Exception("expected version format differs")

Version-Release number of selected component (if applicable):
2.6.9-1

How reproducible:
100%

Steps to Reproduce:
1. Set up a cobbler server
2. Try to create a VM with something like "koan --virt --profile test-el6.7-x86_64 --virt-name centos6.7 --force-path --virt-path /var/lib/libvirt/images/centos6.7-disk0-tmp
3. Observe failure

Actual results:
expected version format differs
  File "/usr/lib/python2.7/site-packages/koan/app.py", line 274, in main
    k.run()
   File "/usr/lib/python2.7/site-packages/koan/app.py", line 424, in run
    self.virt()
   File "/usr/lib/python2.7/site-packages/koan/app.py", line 845, in virt
    return self.net_install(after_download)
   File "/usr/lib/python2.7/site-packages/koan/app.py", line 637, in net_install
    if len(version_str) == 0 and not utils.check_version_greater_or_equal(version_str.strip(), "0.2.0"):
   File "/usr/lib/python2.7/site-packages/koan/utils.py", line 592, in check_version_greater_or_equal
    raise Exception("expected version format differs")

Expected results:
Should provision VM

Additional info:
This is due to https://github.com/cobbler/koan/issues/8.  TL;DR: app.py needs to account for virt-install --version emitting on stderr rather than stdout the way that virtinstall.py does.

Here's a patch that fixes it:

--- /usr/lib/python2.7/site-packages/koan/app.py.dist	2015-10-31 17:29:58.039167678 -0700
+++ /usr/lib/python2.7/site-packages/koan/app.py	2015-10-31 17:31:29.656164095 -0700
@@ -631,7 +631,7 @@
                 if not os.path.exists("/usr/bin/qemu-img"):
                     raise InfoException("qemu package needs to be installed")
                 # is libvirt new enough?
-                rc, version_str = utils.subprocess_get_response(shlex.split('/usr/bin/virt-install --version'), True)
+                rc, stdout, version_str = utils.subprocess_get_response(shlex.split('/usr/bin/virt-install --version'), True, True)
                 print "version_str = %s, %s" % (version_str, utils.subprocess_get_response(shlex.split('/usr/bin/virt-install --version')))
                 version_str = version_str.strip()
                 if len(version_str) == 0 and not utils.check_version_greater_or_equal(version_str.strip(), "0.2.0"):
--- /usr/lib/python2.7/site-packages/koan/utils.py.dist	2015-10-31 17:32:44.778161157 -0700
+++ /usr/lib/python2.7/site-packages/koan/utils.py	2015-10-31 17:36:41.142151913 -0700
@@ -173,7 +173,7 @@
         raise InfoException, "command failed (%s)" % rc
     return rc
 
-def subprocess_get_response(cmd, ignore_rc=False):
+def subprocess_get_response(cmd, ignore_rc=False, get_stderr=False):
     """
     Wrapper around subprocess.check_output(...)
     """
@@ -181,8 +181,11 @@
     rc = 0
     result = ""
     if not ANCIENT_PYTHON:
-        p = sub_process.Popen(cmd, stdout=sub_process.PIPE)
-        result = p.communicate()[0]
+        if get_stderr:
+            p = sub_process.Popen(cmd, stdout=sub_process.PIPE, stderr=sub_process.PIPE)
+        else:
+            p = sub_process.Popen(cmd, stdout=sub_process.PIPE)
+        result, stderr_result = p.communicate()
         rc = p.wait()
     else:
         cmd = string.join(cmd, " ")
@@ -190,6 +193,8 @@
         rc = os.system(cmd)
     if not ignore_rc and rc != 0:
         raise InfoException, "command failed (%s)" % rc
+    if get_stderr:
+        return rc, result, stderr_result
     return rc, result
 
 def input_string_or_hash(options,delim=None,allow_multiples=True):

Understood that this needs a fix upstream, but can we please patch the existing 2.6.9 and issue a hotfix release until upstream gets a release together with this needed change as this prevents us from deploying VMs on EL 7.1.