Support of PyMySQL driver for MySQL backend

Add the ability to use python-pymysql library as backend for MySQL
connections.

Update acceptance tests to use pyMySQL.

Change-Id: Id27afb52428a50ec889e8ae77f3509e1ca956538
Docs: https://wiki.openstack.org/wiki/PyMySQL_evaluation

examples/site.pp

@@ -15,7 +15,7 @@ node default {
   class { '::heat':
     # The keystone_password parameter is mandatory
     keystone_password => 'password',
-    sql_connection    => 'mysql://heat:heat@localhost/heat'
+    sql_connection    => 'mysql+pymysql://heat:heat@localhost/heat'
   }
 
   # Install heat-engine

manifests/db.pp

@@ -49,6 +49,7 @@ class heat::db (
 ) {
 
   include ::heat::deps
+  include ::heat::params
 
   # NOTE(spredzy): In order to keep backward compatibility we rely on the pick function
   # to use heat::<myparam> if heat::db::<myparam> isn't specified.
@@ -62,13 +63,17 @@ class heat::db (
   $sync_db_real = pick($::heat::sync_db, $sync_db)
 
   validate_re($database_connection_real,
-    '(sqlite|mysql|postgresql):\/\/(\S+:\S+@\S+\/\S+)?')
+    '^(sqlite|mysql(\+pymysql)?|postgresql):\/\/(\S+:\S+@\S+\/\S+)?')
 
   case $database_connection_real {
-    /^mysql:\/\//: {
-      $backend_package = false
+    /^mysql(\+pymysql)?:\/\//: {
       require 'mysql::bindings'
       require 'mysql::bindings::python'
+      if $database_connection_real =~ /^mysql\+pymysql/ {
+        $backend_package = $::heat::params::pymysql_package_name
+      } else {
+        $backend_package = false
+      }
     }
     /^postgresql:\/\//: {
       $backend_package = false

manifests/params.pp

@@ -17,6 +17,7 @@ class heat::params {
       $client_package_name = 'python-heatclient'
       $common_package_name = 'openstack-heat-common'
       $sqlite_package_name  = undef
+      $pymysql_package_name = undef
       # service names
       $api_service_name = 'openstack-heat-api'
       $api_cloudwatch_service_name = 'openstack-heat-api-cloudwatch'
@@ -32,6 +33,7 @@ class heat::params {
       $client_package_name = 'python-heatclient'
       $common_package_name = 'heat-common'
       $sqlite_package_name  = 'python-pysqlite2'
+      $pymysql_package_name = 'python-pymysql'
       # service names
       $api_service_name = 'heat-api'
       $api_cloudwatch_service_name = 'heat-api-cloudwatch'

spec/acceptance/basic_heat_spec.rb

@@ -32,7 +32,7 @@ describe 'basic heat' do
         rabbit_userid       => 'heat',
         rabbit_password     => 'an_even_bigger_secret',
         rabbit_host         => '127.0.0.1',
-        database_connection => 'mysql://heat:a_big_secret@127.0.0.1/heat?charset=utf8',
+        database_connection => 'mysql+pymysql://heat:a_big_secret@127.0.0.1/heat?charset=utf8',
         identity_uri        => 'http://127.0.0.1:35357/',
         keystone_password   => 'a_big_secret',
         debug               => true,

spec/classes/heat_db_spec.rb

@@ -18,7 +18,7 @@ describe 'heat::db' do
 
     context 'with specific parameters' do
       let :params do
-        { :database_connection     => 'mysql://heat:heat@localhost/heat',
+        { :database_connection     => 'mysql+pymysql://heat:heat@localhost/heat',
           :database_idle_timeout   => '3601',
           :database_min_pool_size  => '2',
           :database_max_pool_size  => '12',
@@ -28,7 +28,7 @@ describe 'heat::db' do
       end
 
       it { is_expected.not_to contain_class('heat::db::sync') }
-      it { is_expected.to contain_heat_config('database/connection').with_value('mysql://heat:heat@localhost/heat').with_secret(true) }
+      it { is_expected.to contain_heat_config('database/connection').with_value('mysql+pymysql://heat:heat@localhost/heat').with_secret(true) }
       it { is_expected.to contain_heat_config('database/idle_timeout').with_value('3601') }
       it { is_expected.to contain_heat_config('database/min_pool_size').with_value('2') }
       it { is_expected.to contain_heat_config('database/max_pool_size').with_value('12') }
@@ -37,6 +37,14 @@ describe 'heat::db' do
 
     end
 
+    context 'with MySQL-python library as backend package' do
+      let :params do
+        { :database_connection => 'mysql://heat:heat@localhost/heat' }
+      end
+
+      it { is_expected.to contain_heat_config('database/connection').with_value('mysql://heat:heat@localhost/heat').with_secret(true) }
+    end
+
     context 'with postgresql backend' do
       let :params do
         { :database_connection     => 'postgresql://heat:heat@localhost/heat', }
@@ -56,6 +64,14 @@ describe 'heat::db' do
       it_raises 'a Puppet::Error', /validate_re/
     end
 
+    context 'with incorrect database_connection string' do
+      let :params do
+        { :database_connection     => 'foo+pymysql://heat:heat@localhost/heat', }
+      end
+
+      it_raises 'a Puppet::Error', /validate_re/
+    end
+
   end
 
   context 'on Debian platforms' do
@@ -68,6 +84,14 @@ describe 'heat::db' do
     end
 
     it_configures 'heat::db'
+
+    context 'using pymysql driver' do
+      let :params do
+        { :database_connection     => 'mysql+pymysql://heat:heat@localhost/heat' }
+      end
+
+      it { is_expected.to contain_package('heat-backend-package').with({ :ensure => 'present', :name => 'python-pymysql' }) }
+    end
   end
 
   context 'on Redhat platforms' do
@@ -79,6 +103,14 @@ describe 'heat::db' do
     end
 
     it_configures 'heat::db'
+
+    context 'using pymysql driver' do
+      let :params do
+        { :database_connection     => 'mysql+pymysql://heat:heat@localhost/heat' }
+      end
+
+      it { is_expected.not_to contain_package('heat-backend-package') }
+    end
   end
 
 end

spec/classes/heat_init_spec.rb

@@ -14,7 +14,7 @@ describe 'heat' do
       :rabbit_userid         => '<SERVICE DEFAULT>',
       :rabbit_password       => '',
       :rabbit_virtual_host   => '<SERVICE DEFAULT>',
-      :database_connection   => 'mysql://user@host/database',
+      :database_connection   => 'mysql+pymysql://user@host/database',
       :database_idle_timeout => 3600,
       :auth_uri              => 'http://127.0.0.1:5000/v2.0',
       :keystone_ec2_uri      => 'http://127.0.0.1:5000/v2.0/ec2tokens',