Support to set external_network_bridge empty

external_network_bridge could be empty to support multiple external
networks, update l3_agent recipe to support this situation.

Change-Id: Idca94b9d40df750f89e70567e641fe96b6f4a4b1
Closes-Bug: #1483994

attributes/default.rb

@@ -375,7 +375,8 @@ default['openstack']['network']['l3']['gateway_external_network_name'] = nil
 default['openstack']['network']['l3']['handle_internal_only_routers'] = 'True'
 
 # Name of bridge used for external network traffic. This should be set to
-# empty value for the linux bridge
+# empty value for the linux bridge. When external_network_bridge is empty or nil,
+# creation of external bridge will be skipped in the recipe.
 default['openstack']['network']['l3']['external_network_bridge'] = 'br-ex'
 
 # Interface to use for external bridge.

recipes/l3_agent.rb

@@ -120,14 +120,16 @@ case driver_name
 when 'OVSInterfaceDriver'
   ext_bridge = node['openstack']['network']['l3']['external_network_bridge']
   ext_bridge_iface = node['openstack']['network']['l3']['external_network_bridge_interface']
-  execute 'enable external_network_bridge_interface' do
-    command "ip link set #{ext_bridge_iface} up"
-  end
-  execute 'create external network bridge' do
-    command "ovs-vsctl add-br #{ext_bridge} && ovs-vsctl add-port #{ext_bridge} #{ext_bridge_iface}"
-    action :run
-    not_if "ovs-vsctl br-exists #{ext_bridge}"
-    only_if "ip link show #{ext_bridge_iface}"
+  unless ext_bridge.to_s.empty?
+    execute 'create external network bridge' do
+      command "ovs-vsctl add-br #{ext_bridge}"
+      action :run
+      not_if "ovs-vsctl br-exists #{ext_bridge}"
+    end
+    execute 'enable external_network_bridge_interface' do
+      command "ip link set #{ext_bridge_iface} up && ovs-vsctl add-port #{ext_bridge} #{ext_bridge_iface}"
+      only_if "ip link show #{ext_bridge_iface}"
+    end
   end
 when 'BridgeInterfaceDriver'
   # TODO: Handle linuxbridge case

spec/l3_agent-redhat_spec.rb

@@ -7,6 +7,7 @@ describe 'openstack-network::l3_agent' do
     let(:node) { runner.node }
     let(:chef_run) do
       node.set['openstack']['compute']['network']['service_type'] = 'neutron'
+      stub_command('ovs-vsctl br-exists br-ex').and_return(false)
       runner.converge(described_recipe)
     end
 

spec/l3_agent_spec.rb

@@ -12,6 +12,10 @@ describe 'openstack-network::l3_agent' do
       runner.converge(described_recipe)
     end
 
+    before do
+      stub_command('ovs-vsctl br-exists br-ex').and_return(false)
+    end
+
     include_context 'neutron-stubs'
 
     it 'starts the l3 agent on boot' do
@@ -72,14 +76,20 @@ describe 'openstack-network::l3_agent' do
           let(:file_name) { file.name }
         end
 
-        %w(handle_internal_only_routers external_network_bridge metadata_port send_arp_for_ha
-           periodic_interval periodic_fuzzy_delay router_delete_namespaces).each do |attr|
+        %w(handle_internal_only_routers metadata_port send_arp_for_ha periodic_interval
+           periodic_fuzzy_delay router_delete_namespaces).each do |attr|
           it "displays the #{attr} l3 attribute" do
             node.set['openstack']['network']['l3'][attr] = "network_l3_#{attr}_value"
             expect(chef_run).to render_file(file.name).with_content(/^#{attr} = network_l3_#{attr}_value$/)
           end
         end
 
+        it 'displays the external_network_bridge l3 attribute' do
+          node.set['openstack']['network']['l3']['external_network_bridge'] = 'network_l3_external_network_bridge_value'
+          stub_command('ovs-vsctl br-exists network_l3_external_network_bridge_value').and_return(false)
+          expect(chef_run).to render_file(file.name).with_content(/^external_network_bridge = network_l3_external_network_bridge_value$/)
+        end
+
         it 'sets the agent_mode attribute to dvr_snat' do
           node.set['openstack']['network']['l3']['router_distributed'] = true
           allow_any_instance_of(Chef::Recipe).to receive(:recipe_included?).with('openstack-network::server').and_return(true)
@@ -157,39 +167,46 @@ describe 'openstack-network::l3_agent' do
     end
 
     describe 'create ovs bridges' do
-      let(:iplink) { 'ip link set eth1 up' }
-      let(:cmd) { 'ovs-vsctl add-br br-ex && ovs-vsctl add-port br-ex eth1' }
+      let(:cmd) { 'ovs-vsctl add-br br-ex' }
+      let(:iplink) { 'ip link set eth1 up && ovs-vsctl add-port br-ex eth1' }
 
-      it "doesn't add the external bridge if it already exists" do
-        stub_command(/ovs-vsctl br-exists/).and_return(true)
-        stub_command(/ip link show eth1/).and_return(true)
+      it 'does not add the external bridge and disable external_network_bridge_interface if external_network_bridge is empty' do
+        node.set['openstack']['network']['l3']['external_network_bridge'] = ''
 
-        expect(chef_run).to run_execute(iplink)
         expect(chef_run).not_to run_execute(cmd)
+        expect(chef_run).not_to run_execute(iplink)
       end
 
-      it "doesn't add the external bridge if the physical interface doesn't exist" do
-        stub_command(/ovs-vsctl br-exists/).and_return(true)
+      it 'does not add the external bridge if it already exists' do
+        stub_command(/ovs-vsctl br-exists br-ex/).and_return(true)
+        stub_command(/ip link show eth1/).and_return(true)
+
+        expect(chef_run).not_to run_execute(cmd)
+        expect(chef_run).to run_execute(iplink)
+      end
+
+      it 'disable external_network_bridge_interface if the physical interface does not exist' do
+        stub_command(/ovs-vsctl br-exists br-ex/).and_return(false)
         stub_command(/ip link show eth1/).and_return(false)
 
-        expect(chef_run).to run_execute(iplink)
-        expect(chef_run).not_to run_execute(cmd)
+        expect(chef_run).to run_execute(cmd)
+        expect(chef_run).not_to run_execute(iplink)
       end
 
       it 'adds the external bridge if it does not yet exist' do
-        stub_command(/ovs-vsctl br-exists/).and_return(false)
+        stub_command(/ovs-vsctl br-exists br-ex/).and_return(false)
         stub_command(/ip link show eth1/).and_return(true)
 
-        expect(chef_run).to run_execute(iplink)
         expect(chef_run).to run_execute(cmd)
+        expect(chef_run).to run_execute(iplink)
       end
 
-      it 'adds the external bridge if the physical interface exists' do
-        stub_command(/ovs-vsctl br-exists/).and_return(false)
+      it 'enable external_network_bridge_interface if the physical interface exists' do
+        stub_command(/ovs-vsctl br-exists br-ex/).and_return(false)
         stub_command(/ip link show eth1/).and_return(true)
 
-        expect(chef_run).to run_execute(iplink)
         expect(chef_run).to run_execute(cmd)
+        expect(chef_run).to run_execute(iplink)
       end
     end
   end

spec/vpn_agent-redhat_spec.rb

@@ -8,6 +8,7 @@ describe 'openstack-network::vpn_agent' do
     let(:chef_run) do
       node.set['openstack']['compute']['network']['service_type'] = 'neutron'
       node.set['openstack']['network']['enable_vpn'] = true
+      stub_command('ovs-vsctl br-exists br-ex').and_return(false)
       runner.converge(described_recipe)
     end
 

spec/vpn_agent_spec.rb

@@ -8,6 +8,7 @@ describe 'openstack-network::vpn_agent' do
     let(:chef_run) do
       node.set['openstack']['compute']['network']['service_type'] = 'neutron'
       node.set['openstack']['network']['enable_vpn'] = true
+      stub_command('ovs-vsctl br-exists br-ex').and_return(false)
       runner.converge(described_recipe)
     end