Add multi-region support

If only one region is available then the Neutron CLI will just pick the
only one available.  However, if more than one is available, then it
will error out about ambiguous region.  This patch extends the base
provider code to parse out the nova_region_name when it's parsing out
the keystone credentials and define the OS_REGION_NAME environment
variable when calling neutron, if the nova_region_name variable exists
in the config file.

Closes-Bug: #1329552
Change-Id: Ic0d59dcb02a11e93e8fad1e0e2ea830fb0dcccc7

lib/puppet/provider/neutron.rb

@@ -31,8 +31,12 @@ def self.get_neutron_credentials
     conf = neutron_conf
     if conf and conf['keystone_authtoken'] and
         auth_keys.all?{|k| !conf['keystone_authtoken'][k].nil?}
-      return Hash[ auth_keys.map \
+      creds = Hash[ auth_keys.map \
                    { |k| [k, conf['keystone_authtoken'][k].strip] } ]
+      if conf['DEFAULT'] and !conf['DEFAULT']['nova_region_name'].nil?
+        creds['nova_region_name'] = conf['DEFAULT']['nova_region_name']
+      end
+      return creds
     else
       raise(Puppet::Error, "File: #{conf_filename} does not contain all \
 required sections.  Neutron types will not work if neutron is not \
@@ -68,6 +72,9 @@ def self.auth_neutron(*args)
       :OS_TENANT_NAME => q['admin_tenant_name'],
       :OS_PASSWORD    => q['admin_password']
     }
+    if q.key?('nova_region_name')
+      authenv[:OS_REGION_NAME] = q['nova_region_name']
+    end
     begin
       withenv authenv do
         neutron(args)

spec/unit/provider/neutron_spec.rb

@@ -64,6 +64,15 @@ def klass
       klass.get_auth_endpoint.should == auth_endpoint
     end
 
+    it 'should find region_name if specified' do
+      conf = {
+        'keystone_authtoken' => credential_hash,
+        'DEFAULT' => { 'nova_region_name' => 'REGION_NAME' }
+      }
+      klass.expects(:neutron_conf).returns(conf)
+      klass.neutron_credentials['nova_region_name'] == 'REGION_NAME'
+    end
+
   end
 
   describe 'when invoking the neutron cli' do
@@ -80,6 +89,21 @@ def klass
       klass.auth_neutron('test_retries')
     end
 
+    it 'should set region in the environment if needed' do
+      authenv = {
+        :OS_AUTH_URL    => auth_endpoint,
+        :OS_USERNAME    => credential_hash['admin_user'],
+        :OS_TENANT_NAME => credential_hash['admin_tenant_name'],
+        :OS_PASSWORD    => credential_hash['admin_password'],
+        :OS_REGION_NAME => 'REGION_NAME',
+      }
+
+      cred_hash = credential_hash.merge({'nova_region_name' => 'REGION_NAME'})
+      klass.expects(:get_neutron_credentials).with().returns(cred_hash)
+      klass.expects(:withenv).with(authenv)
+      klass.auth_neutron('test_retries')
+    end
+
     ['[Errno 111] Connection refused',
      '(HTTP 400)'].reverse.each do |valid_message|
       it "should retry when neutron cli returns with error #{valid_message}" do