Support of PyMySQL driver for MySQL backend

Add ability to use python-pymysql library
as backend for MySQL connections.
Update acceptance tests to use pyMySQL.
Docs: https://wiki.openstack.org/wiki/PyMySQL_evaluation
The same implementation as it's done for keystone:
https://review.openstack.org/#/c/242134/

Change-Id: I937aa59984e6ff2f7aff28f56ce79e117e5aa0a9

manifests/db.pp

@@ -43,6 +43,8 @@ class trove::db (
   $database_max_overflow   = 20,
 ) {
 
+  include ::trove::params
+
   # NOTE(spredzy): In order to keep backward compatibility we rely on the pick function
   # to use trove::<myparam> if trove::db::<myparam> isn't specified.
   $database_connection_real     = pick($::trove::database_connection, $database_connection)
@@ -54,14 +56,18 @@ class trove::db (
   $database_max_overflow_real   = pick($::trove::database_max_overflow, $database_max_overflow)
 
   validate_re($database_connection_real,
-    '(sqlite|mysql|postgresql):\/\/(\S+:\S+@\S+\/\S+)?')
+    '^(sqlite|mysql(\+pymysql)?|postgresql):\/\/(\S+:\S+@\S+\/\S+)?')
 
   if $database_connection_real {
     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 = $::trove::params::pymysql_package_name
+        } else {
+          $backend_package = false
+        }
       }
       /^postgresql:\/\//: {
         $backend_package = false

manifests/params.pp

@@ -15,6 +15,7 @@ class trove::params {
       $taskmanager_package_name = 'openstack-trove-taskmanager'
       $taskmanager_service_name = 'openstack-trove-taskmanager'
       $sqlite_package_name      = undef
+      $pymysql_package_name     = 'python2-PyMySQL'
     }
     'Debian': {
       $client_package_name      = 'python-troveclient'
@@ -28,6 +29,7 @@ class trove::params {
       $taskmanager_package_name = 'trove-taskmanager'
       $taskmanager_service_name = 'trove-taskmanager'
       $sqlite_package_name      = 'python-pysqlite2'
+      $pymysql_package_name     = 'python-pymysql'
     }
     default: {
       fail("Unsupported osfamily: ${::osfamily} operatingsystem")

spec/acceptance/basic_trove_spec.rb

@@ -29,7 +29,7 @@ describe 'basic trove' do
 
       # Trove resources
       class { '::trove':
-        database_connection   => 'mysql://trove:a_big_secret@127.0.0.1/trove?charset=utf8',
+        database_connection   => 'mysql+pymysql://trove:a_big_secret@127.0.0.1/trove?charset=utf8',
         rabbit_userid         => 'trove',
         rabbit_password       => 'an_even_bigger_secret',
         rabbit_host           => '127.0.0.1',

spec/classes/trove_db_spec.rb

@@ -18,7 +18,7 @@ describe 'trove::db' do
 
     context 'with specific parameters' do
       let :params do
-        { :database_connection     => 'mysql://trove:trove@localhost/trove',
+        { :database_connection     => 'mysql+pymysql://trove:trove@localhost/trove',
           :database_idle_timeout   => '3601',
           :database_min_pool_size  => '2',
           :database_max_pool_size  => '21',
@@ -27,16 +27,25 @@ describe 'trove::db' do
           :database_retry_interval => '11', }
       end
 
-      it { is_expected.to contain_trove_config('database/connection').with_value('mysql://trove:trove@localhost/trove').with_secret(true) }
+      it { is_expected.to contain_trove_config('database/connection').with_value('mysql+pymysql://trove:trove@localhost/trove').with_secret(true) }
       it { is_expected.to contain_trove_config('database/idle_timeout').with_value('3601') }
       it { is_expected.to contain_trove_config('database/min_pool_size').with_value('2') }
       it { is_expected.to contain_trove_config('database/max_retries').with_value('11') }
       it { is_expected.to contain_trove_config('database/max_pool_size').with_value('21') }
       it { is_expected.to contain_trove_config('database/max_overflow').with_value('21') }
       it { is_expected.to contain_trove_config('database/retry_interval').with_value('11') }
+      it { is_expected.to contain_package('trove-backend-package').with({ :ensure => 'present', :name => platform_params[:pymysql_package_name] }) }
 
     end
 
+    context 'with MySQL-python library as backend package' do
+      let :params do
+        { :database_connection     => 'mysql://trove:trove@localhost/trove', }
+			      end
+
+      it { is_expected.to contain_package('python-mysqldb').with(:ensure => 'present') }
+    end
+
     context 'with postgresql backend' do
       let :params do
         { :database_connection     => 'postgresql://trove:trove@localhost/trove', }
@@ -56,6 +65,14 @@ describe 'trove::db' do
       it_raises 'a Puppet::Error', /validate_re/
     end
 
+    context 'with incorrect pymysql database_connection string' do
+      let :params do
+        { :database_connection     => 'foo+pymysql://trove:trove@localhost/trove', }
+      end
+
+      it_raises 'a Puppet::Error', /validate_re/
+    end
+
   end
 
   context 'on Debian platforms' do
@@ -66,6 +83,10 @@ describe 'trove::db' do
       }
     end
 
+    let :platform_params do
+      { :pymysql_package_name => 'python-pymysql' }
+    end
+
     it_configures 'trove::db'
   end
 
@@ -76,6 +97,10 @@ describe 'trove::db' do
       }
     end
 
+    let :platform_params do
+      { :pymysql_package_name => 'python2-PyMySQL' }
+    end
+
     it_configures 'trove::db'
   end