Add database slave connection support

- Add new attributes for database slave connection
- Change db_uri method to generate slave connection db_uri

Implements: blueprint sql-slave-connection-support
Change-Id: I9996e4944e58264b5195d625c98adaf28a04acd7

attributes/database.rb

@@ -76,6 +76,9 @@ default['openstack']['endpoints']['db']['scheme'] = nil
 default['openstack']['endpoints']['db']['port'] = '3306'
 default['openstack']['endpoints']['db']['path'] = nil
 default['openstack']['endpoints']['db']['bind_interface'] = nil
+default['openstack']['endpoints']['db']['enabled_slave'] = false
+default['openstack']['endpoints']['db']['slave_host'] = '127.0.0.1'
+default['openstack']['endpoints']['db']['slave_port'] = '3316'
 
 # Default database attributes
 default['openstack']['db']['server_role'] = 'os-ops-database'
@@ -141,6 +144,9 @@ node['openstack']['common']['services'].each do |service, project|
   default['openstack']['db'][service]['username'] = project
   default['openstack']['db'][service]['options'] = node['openstack']['db']['options']
 
+  default['openstack']['db'][service]['slave_host'] = node['openstack']['endpoints']['db']['slave_host']
+  default['openstack']['db'][service]['slave_port'] = node['openstack']['endpoints']['db']['slave_port']
+
   case service
   when 'dashboard'
     default['openstack']['db'][service]['migrate'] = true

libraries/endpoints.rb

@@ -52,11 +52,17 @@ module ::Openstack
   end
 
   # Shortcut to get the SQLAlchemy DB URI for a named service
-  def db_uri(service, user, pass) # rubocop:disable MethodLength, CyclomaticComplexity
+  def db_uri(service, user, pass, is_slave = false) # rubocop:disable MethodLength, CyclomaticComplexity
     info = db(service)
     return unless info
-    host = info['host']
-    port = info['port'].to_s
+
+    if is_slave
+      host  = info['slave_host']
+      port = info['slave_port'].to_s
+    else
+      host = info['host']
+      port = info['port'].to_s
+    end
     type = info['service_type']
     name = info['db_name']
     options = info['options'][type]

spec/endpoints_spec.rb

@@ -403,6 +403,48 @@ describe 'openstack-common::set_endpoints_by_interface' do
           ).to eq(expected)
         end
       end
+
+      it 'returns compute slave db info hash when service found for default mysql' do
+        node.set['openstack']['endpoints']['db']['enabled_slave'] = true
+        allow(subject).to receive(:node).and_return(chef_run.node)
+        expected = 'mysql://user:pass@127.0.0.1:3316/nova?charset=utf8'
+        expect(
+          subject.db_uri('compute', 'user', 'pass', true)
+        ).to eq(expected)
+      end
+
+      it 'returns block-storage slave db info hash when service found for db2 with options' do
+        node.set['openstack']['endpoints']['db']['enabled_slave'] = true
+        node.set['openstack']['db']['service_type'] = 'db2'
+        node.set['openstack']['db']['options'] = { 'db2' => '?options' }
+        allow(subject).to receive(:node).and_return(chef_run.node)
+        expected = 'ibm_db_sa://user:pass@127.0.0.1:3316/cinder?options'
+        expect(
+          subject.db_uri('block-storage', 'user', 'pass', true)
+        ).to eq(expected)
+      end
+
+      it 'returns image slave db info hash when service found for mariadb' do
+        node.set['openstack']['db']['service_type'] = 'mariadb'
+        node.set['openstack']['endpoints']['db']['enabled_slave'] = true
+        allow(subject).to receive(:node).and_return(chef_run.node)
+        expected = 'mysql://user:pass@127.0.0.1:3316/glance?charset=utf8'
+        expect(
+          subject.db_uri('image', 'user', 'pass', true)
+        ).to eq(expected)
+      end
+
+      %w(galera percona-cluster).each do |db|
+        it "returns network slave db info hash when service found for #{db}" do
+          node.set['openstack']['db']['service_type'] = db
+          node.set['openstack']['endpoints']['db']['enabled_slave'] = true
+          allow(subject).to receive(:node).and_return(chef_run.node)
+          expected = 'mysql://user:pass@127.0.0.1:3316/neutron?charset=utf8'
+          expect(
+            subject.db_uri('network', 'user', 'pass', true)
+          ).to eq(expected)
+        end
+      end
     end
 
     describe '#address' do