snf_django: Use option groups in SynnefoCommand

Extend SynnefoCommand to use option groups to distinguish between common
and command-specific options, by overriding the 'create_parser' method.
The command specific options must be declared in the
'command_option_list' attribute of the SynnefoCommand. Also, we use a
custom formatter to pretty-print options.

snf-cyclades-app/synnefo/logic/management/commands/stats-cyclades.py

@@ -48,7 +48,7 @@ class Command(SynnefoCommand):
     help = "Get available statistics of Cyclades service"
     can_import_settings = True
 
-    option_list = SynnefoCommand.option_list + (
+    command_option_list = (
         make_option("--backend",
                     dest="backend",
                     help="Include statistics only for this backend."),

snf-cyclades-app/synnefo/quotas/management/commands/enforce-resources-cyclades.py

@@ -52,7 +52,8 @@ DEFAULT_RESOURCES = ["cyclades.cpu",
 class Command(SynnefoCommand):
     help = """Check and fix quota violations for Cyclades resources.
     """
-    option_list = SynnefoCommand.option_list + (
+
+    command_option_list = (
         make_option("--max-operations",
                     help="Limit operations per backend."),
         make_option("--users", dest="users",

snf-django-lib/snf_django/management/commands/__init__.py

-# Copyright 2012-2013 GRNET S.A. All rights reserved.
+# Copyright 2012-2014 GRNET S.A. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or
 # without modification, are permitted provided that the following
@@ -31,7 +31,8 @@
 # interpreted as representing official policies, either expressed
 # or implied, of GRNET S.A.
 
-from optparse import make_option
+from optparse import (make_option, OptionParser, OptionGroup,
+                      TitledHelpFormatter)
 
 from django.core.management.base import BaseCommand, CommandError
 from django.core.exceptions import FieldError
@@ -44,6 +45,13 @@ import distutils
 USER_EMAIL_FIELD = "user.email"
 
 
+class SynnefoCommandFormatter(TitledHelpFormatter):
+    def format_heading(self, heading):
+        if heading == "Options":
+            return ""
+        return "%s\n%s\n" % (heading, "=-"[self.level] * len(heading))
+
+
 class SynnefoCommand(BaseCommand):
     option_list = BaseCommand.option_list + (
         make_option(
@@ -56,6 +64,34 @@ class SynnefoCommand(BaseCommand):
                  "csv [comma-separated output]"),
     )
 
+    def create_parser(self, prog_name, subcommand):
+        parser = OptionParser(prog=prog_name, add_help_option=False,
+                              formatter=SynnefoCommandFormatter())
+
+        parser.set_usage(self.usage(subcommand))
+        parser.version = self.get_version()
+
+        # Handle Django's and common options
+        common_options = OptionGroup(parser, "Common Options")
+        common_options.add_option("-h", "--help", action="help",
+                                  help="show this help message and exit")
+
+        common_options.add_option("--version", action="version",
+                                  help="show program's version number and"
+                                       "  exit")
+        [common_options.add_option(o) for o in self.option_list]
+        if common_options.option_list:
+            parser.add_option_group(common_options)
+
+        # Handle command specific options
+        command_options = OptionGroup(parser, "Command Specific Options")
+        [command_options.add_option(o)
+         for o in getattr(self, "command_option_list", ())]
+        if command_options.option_list:
+            parser.add_option_group(command_options)
+
+        return parser
+
 
 class ListCommand(SynnefoCommand):
     """Generic *-list management command.