Refactors and adds connect region tags to Cloud SQL sample. (GoogleCloudPlatform#965)

Author: kurtisvg

cloud_sql/postgres/pdo/README.md

@@ -14,7 +14,7 @@ export CLOUD_SQL_CONNECTION_NAME='::'
 export DB_USER='my-db-user'
 export DB_PASS='my-db-pass'
 export DB_NAME='my-db-name'
-export DB_HOSTNAME='localhost' # If connecting using cloud_sql_proxy
+export DB_HOSTNAME='localhost' # If connecting using TCP instead of Unix Sockets
 ```
 
 Note: Saving credentials in environment variables is convenient, but not secure - consider a more secure solution such as [Cloud KMS](https://cloud.google.com/kms/) to help keep secrets safe.
@@ -31,21 +31,10 @@ $ ./cloud_sql_proxy -dir=/cloudsql --instances=$CLOUD_SQL_CONNECTION_NAME --cred
 
 Note: Make sure to run the command under a user with write access in the `/cloudsql` directory. This proxy will use this folder to create a unix socket the application will use to connect to Cloud SQL.
 
-Next, install the dependencies using Composer:
-
-```bash
-$ composer install
-```
-OR
-
-```bash
-$ php composer.phar install
-```
-
 Execute the following:
 
 ```bash
-$ php -S localhost:8080 index.php
+$ php -S localhost:8080
 ```
 
 Navigate towards http://localhost:8080 to verify your application is running correctly.

cloud_sql/postgres/pdo/app.yaml

@@ -17,7 +17,7 @@ runtime: php72
 # Remember - storing secrets in plaintext is potentially unsafe. Consider using
 # something like https://cloud.google.com/kms/ to help keep secrets secret.
 env_variables:
-  CLOUD_SQL_INSTANCE_NAME: ::
+  CLOUD_SQL_CONNECTION_NAME: ::
   DB_USER: my-db-user
   DB_PASS: my-db-pass
   DB_NAME: my_db

cloud_sql/postgres/pdo/composer.json

@@ -13,12 +13,13 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-require 'vendor/autoload.php';
+require_once 'src/DB.php';
+require_once 'src/Votes.php';
 
 use Google\Cloud\Samples\CloudSQL\Postgres\DB;
 use Google\Cloud\Samples\CloudSQL\Postgres\Votes;
 
-$votes = new Votes(new DB());
+$votes = new Votes(DB::createPdoConnection());
 
 if ($_SERVER['REQUEST_URI'] == '/' && $_SERVER['REQUEST_METHOD'] == 'GET') {
     $list = $votes->list();

cloud_sql/postgres/pdo/index.php

@@ -19,34 +19,33 @@
 
 class DB
 {
-    private $connection;
-
-    public function __construct()
-    {
-        $config = [
-            "username" => getenv("DB_USER"),
-            "password" => getenv("DB_PASS"),
-            "schema" => getenv("DB_NAME"),
-            "hostname" => getenv("DB_HOSTNAME") ?: "127.0.0.1",
-            "cloud_sql_instance_name" => getenv("CLOUD_SQL_INSTANCE_NAME")
-        ];
-
-        $this->connection = $this->connect($config);
-    }
-
-    private function connect($config)
+    public static function createPdoConnection()
     {
-        $dsn = "pgsql:dbname={$config['schema']};host={$config['hostname']}";
-
-        if ($config["cloud_sql_instance_name"] != "") {
-            $dsn = "pgsql:dbname={$config['schema']};host=/cloudsql/{$config['cloud_sql_instance_name']}";
+        $username = getenv("DB_USER");
+        $password = getenv("DB_PASS");
+        $schema = getenv("DB_NAME");
+        $hostname = getenv("DB_HOSTNAME") ?: "127.0.0.1";
+        $cloud_sql_connection_name = getenv("CLOUD_SQL_CONNECTION_NAME");
+        # [START cloud_sql_postgres_pdo_create]
+        // $username = 'your_db_user';
+        // $password = 'yoursupersecretpassword';
+        // $schema = 'your_db_name';
+        // $cloud_sql_connection_name = 'Your Cloud SQL Connection name';
+
+        if ($cloud_sql_connection_name) {
+            // Connect using UNIX sockets
+            $dsn = sprintf(
+                'pgsql:dbname=%s;host=/cloudsql/%s',
+                $schema,
+                $cloud_sql_connection_name
+            );
+        } else {
+            // Connect using TCP
+            // $hostname = '127.0.0.1';
+            $dsn = sprintf('pgsql:dbname=%s;host=%s', $schema, $hostname);
         }
 
-        return new PDO($dsn, $config['username'], $config['password']);
-    }
-
-    public function get_connection()
-    {
-        return $this->connection;
+        return new PDO($dsn, $username, $password);
+        # [END cloud_sql_postgres_pdo_create]
     }
 }

cloud_sql/postgres/pdo/src/DB.php

@@ -15,13 +15,15 @@
 
 namespace Google\Cloud\Samples\CloudSQL\Postgres;
 
+use PDO;
+
 class Votes
 {
     private $connection;
 
-    public function __construct(DB $db)
+    public function __construct(PDO $connection)
     {
-        $this->connection = $db->get_connection();
+        $this->connection = $connection;
         $this->create_table();
     }
 
@@ -42,7 +44,7 @@ public function list()
         $sql = "SELECT candidate, time_cast FROM votes ORDER BY time_cast DESC LIMIT 5";
         $statement = $this->connection->prepare($sql);
         $statement->execute();
-        
+
         return $statement->fetchAll();
     }