Use AMQP fallback endpoints when available

Qpid proton allows for automatic failover in case an error occurs for
the currently active connection. When the Nuage provider is associated
with endpoints with roles `amqp-fallback1` and `amqp-fallback2`, these
will be used to configure the message handler.

Signed-off-by: Gregor Berginc <[email protected]>

app/models/manageiq/providers/nuage/manager_mixin.rb

@@ -53,26 +53,27 @@ def verify_credentials(auth_type = nil, options = {})
 
   def event_monitor_options
     @event_monitor_options ||= begin
-      url = ''
-      amqp = connection_configuration_by_role('amqp')
-      if (endpoint = amqp.try(:endpoint))
-        url = "#{endpoint.hostname}:#{endpoint.port}"
-      end
-
-      if (authentication = amqp.try(:authentication))
-        url = "#{authentication.userid}:#{authentication.password}@#{url}"
-      end
-
       {
         :ems                       => self,
-        :url                       => url,
+        :urls                      => amqp_urls,
         :sasl_allow_insecure_mechs => true, # Only plain (insecure) mechanism currently supported
       }
     end
   end
 
   private
 
+  def amqp_urls
+    amqp_endpoints = endpoints.select { |e| e.role == 'amqp' || e.role.start_with?('amqp_fallback') }
+    amqp_auth      = authentications.detect { |a| a.authtype == 'amqp' }
+
+    amqp_endpoints.map do |e|
+      url = "#{e.hostname}:#{e.port}"
+      url = "#{amqp_auth.userid}:#{amqp_auth.password}@#{url}" if amqp_auth
+      url
+    end
+  end
+
   def verify_api_credentials(options = {})
     with_provider_connection(options) {}
     true

app/models/manageiq/providers/nuage/network_manager/event_catcher/messaging_handler.rb

@@ -5,14 +5,13 @@ def initialize(options = {})
     super()
     @options = options
 
-    @url = @options.delete(:url)
     @topics = @options.delete(:topics)
     @test_connection = @options.delete(:test_connection)
     @message_handler_block = @options.delete(:message_handler_block)
   end
 
   def on_start(event)
-    @conn = event.container.connect(@url, @options)
+    @conn = event.container.connect(@options)
     unless @test_connection
       @topics.each { |topic| event.container.create_receiver(@conn, :source => "topic://#{topic}") }
     end
@@ -28,7 +27,9 @@ def on_connection_error(_event)
   end
 
   def on_transport_error(_event)
-    raise MiqException::MiqHostError, "Transport error"
+    # Only raise error if single URL is used, as otherwise qpid will attempt
+    # to fallback to alternative URLs.
+    raise MiqException::MiqHostError, "Transport error" unless @options[:urls].length > 1
   end
 
   def on_message(event)

spec/models/manageiq/providers/nuage/network_manager_spec.rb

@@ -22,4 +22,30 @@
       end.to raise_error(MiqException::MiqInvalidCredentialsError)
     end
   end
+
+  context '#event_monitor_options' do
+    before(:each) do
+      @ems = FactoryGirl.build(:ems_nuage_network, :hostname => "host", :ipaddress => "::1")
+      @creds = {:amqp => {:userid => "amqp_user", :password => "amqp_pass"}}
+      @ems.endpoints << Endpoint.create(:role => 'amqp', :hostname => 'amqp_hostname', :port => '5672')
+      @ems.update_authentication(@creds, :save => false)
+    end
+
+    it 'returns options with a single endpoint' do
+      opts = @ems.event_monitor_options
+
+      expect(opts).to have_attributes(:urls => ['amqp_user:amqp_pass@amqp_hostname:5672'])
+    end
+
+    it 'returns options with a fallback URLs' do
+      @ems.endpoints << Endpoint.create(:role => 'amqp_fallback1', :hostname => 'amqp_hostname1', :port => '5672')
+      @ems.endpoints << Endpoint.create(:role => 'amqp_fallback2', :hostname => 'amqp_hostname2', :port => '5672')
+
+      opts = @ems.event_monitor_options
+
+      expect(opts[:urls]).to include('amqp_user:amqp_pass@amqp_hostname:5672',
+                                     'amqp_user:amqp_pass@amqp_hostname1:5672',
+                                     'amqp_user:amqp_pass@amqp_hostname2:5672')
+    end
+  end
 end