xenapi: fix pep8 violations in nova plugins

Removed plugins/xenserver from tox.ini excludes list, ran tox -e pep8, and
fixed violations.

Fixes: bug 1197893
Change-Id: I8e0116304b07d54c49a01202b3ce6d3426097bb4

plugins/xenserver/xenapi/etc/xapi.d/plugins/pluginlib_nova.py

@@ -135,7 +135,8 @@ def exists(args, key):
 
 def optional(args, key):
     """If the given key is in args, return the corresponding value, otherwise
-    return None"""
+    return None
+    """
     return key in args and args[key] or None
 
 
@@ -207,7 +208,8 @@ def vbd_unplug_with_retry(session, vbd):
     """Call VBD.unplug on the given VBD, with a retry if we get
     DEVICE_DETACH_REJECTED.  For reasons which I don't understand, we're
     seeing the device still in use, even when all processes using the device
-    should be dead."""
+    should be dead.
+    """
     while True:
         try:
             session.xenapi.VBD.unplug(vbd)
@@ -215,7 +217,7 @@ def vbd_unplug_with_retry(session, vbd):
             return
         except XenAPI.Failure, e:
             if (len(e.details) > 0 and
-                e.details[0] == 'DEVICE_DETACH_REJECTED'):
+                    e.details[0] == 'DEVICE_DETACH_REJECTED'):
                 logging.debug(_('VBD.unplug rejected: retrying...'))
                 time.sleep(1)
             elif (len(e.details) > 0 and

plugins/xenserver/xenapi/etc/xapi.d/plugins/utils.py

@@ -103,6 +103,7 @@ def finish_subprocess(proc, cmdline, cmd_input=None, ok_exit_codes=None):
         raise SubprocessException(' '.join(cmdline), ret, out, err)
     return out
 
+
 def run_command(cmd, cmd_input=None, ok_exit_codes=None):
     """Abstracts out the basics of issuing system commands. If the command
     returns anything in stderr, an exception is raised with that information.

plugins/xenserver/xenapi/etc/xapi.d/plugins/xenstore.py

@@ -64,7 +64,8 @@ def jsonify(fnc):
 
 def _record_exists(arg_dict):
     """Returns whether or not the given record exists. The record path
-    is determined from the given path and dom_id in the arg_dict."""
+    is determined from the given path and dom_id in the arg_dict.
+    """
     cmd = ["xenstore-exists", "/local/domain/%(dom_id)s/%(path)s" % arg_dict]
     try:
         _run_command(cmd)

tox.ini

@@ -51,7 +51,7 @@ commands = {posargs}
 # H102  Apache 2.0 license header not found
 
 ignore = E121,E122,E123,E124,E126,E127,E128,E711,E712,H102,H404,F403,F811,F841,H803
-exclude =  .venv,.git,.tox,dist,doc,*openstack/common*,*lib/python*,*egg,build,*plugins/xenserver*,tools
+exclude =  .venv,.git,.tox,dist,doc,*openstack/common*,*lib/python*,*egg,build,tools
 
 [hacking]
 local-check-factory = nova.hacking.checks.factory