FIX: Ensure that types are preserved fetching from database

This ensures that numeric fields appear in PHP as int/float values
rather than strings, which allows the development of more type-safe PHP
code.

This doesn’t work on the legacy mysql driver and this will now throw
a notice-level error. It requires mysqlnd.

src/ORM/Connect/MySQLiConnector.php

@@ -78,6 +78,18 @@ class MySQLiConnector extends DBConnector
 
         $this->dbConn = mysqli_init();
 
+        // Use native types (MysqlND only)
+        if (defined('MYSQLI_OPT_INT_AND_FLOAT_NATIVE')) {
+            $this->dbConn->options(MYSQLI_OPT_INT_AND_FLOAT_NATIVE, true);
+
+        // The alternative is not ideal, throw a notice-level error
+        } else {
+            user_error(
+                'mysqlnd PHP library is not available, numeric values will be fetched from the DB as strings',
+                E_USER_NOTICE
+            );
+        }
+
         // Set SSL parameters if they exist. All parameters are required.
         if (array_key_exists('ssl_key', $parameters) &&
             array_key_exists('ssl_cert', $parameters) &&

src/ORM/Connect/PDOConnector.php

@@ -64,6 +64,12 @@ class PDOConnector extends DBConnector
      */
     protected $cachedStatements = array();
 
+    /**
+     * Driver
+     * @var string
+     */
+    private $driver = null;
+
     /**
      * Flush all prepared statements
      */
@@ -113,10 +119,11 @@ class PDOConnector extends DBConnector
     {
         $this->flushStatements();
 
-        // Build DSN string
         // Note that we don't select the database here until explicitly
         // requested via selectDatabase
-        $driver = $parameters['driver'] . ":";
+        $this->driver = $parameters['driver'];
+
+        // Build DSN string
         $dsn = array();
 
         // Typically this is false, but some drivers will request this
@@ -195,13 +202,18 @@ class PDOConnector extends DBConnector
             $options[PDO::MYSQL_ATTR_SSL_CIPHER] = array_key_exists('ssl_cipher', $parameters) ? $parameters['ssl_cipher'] : self::config()->get('ssl_cipher_default');
         }
 
-        if (self::is_emulate_prepare()) {
-            $options[PDO::ATTR_EMULATE_PREPARES] = true;
+        // Set emulate prepares (unless null / default)
+        $isEmulatePrepares = self::is_emulate_prepare();
+        if (isset($isEmulatePrepares)) {
+            $options[PDO::ATTR_EMULATE_PREPARES] = (bool)$isEmulatePrepares;
         }
 
+        // Disable stringified fetches
+        $options[PDO::ATTR_STRINGIFY_FETCHES] = false;
+
         // May throw a PDOException if fails
         $this->pdoConnection = new PDO(
-            $driver . implode(';', $dsn),
+            $this->driver . ':' . implode(';', $dsn),
             empty($parameters['username']) ? '' : $parameters['username'],
             empty($parameters['password']) ? '' : $parameters['password'],
             $options
@@ -213,6 +225,16 @@ class PDOConnector extends DBConnector
         }
     }
 
+
+    /**
+     * Return the driver for this connector
+     * E.g. 'mysql', 'sqlsrv', 'pgsql'
+     */
+    public function getDriver()
+    {
+        return $this->driver;
+    }
+
     public function getVersion()
     {
         return $this->pdoConnection->getAttribute(PDO::ATTR_SERVER_VERSION);
@@ -383,7 +405,7 @@ class PDOConnector extends DBConnector
         } elseif ($statement) {
             // Count and return results
             $this->rowCount = $statement->rowCount();
-            return new PDOQuery($statement);
+            return new PDOQuery($statement, $this);
         }
 
         // Ensure statement is closed

src/ORM/Connect/PDOQuery.php

@@ -22,16 +22,54 @@ class PDOQuery extends Query
      * Hook the result-set given into a Query class, suitable for use by SilverStripe.
      * @param PDOStatement $statement The internal PDOStatement containing the results
      */
-    public function __construct(PDOStatement $statement)
+    public function __construct(PDOStatement $statement, PDOConnector $conn)
     {
         $this->statement = $statement;
         // Since no more than one PDOStatement for any one connection can be safely
         // traversed, each statement simply requests all rows at once for safety.
         // This could be re-engineered to call fetchAll on an as-needed basis
-        $this->results = $statement->fetchAll(PDO::FETCH_ASSOC);
+
+        // Special case for Postgres
+        if ($conn->getDriver() == 'pgsql') {
+            $this->results = $this->fetchAllPgsql($statement);
+        } else {
+            $this->results = $statement->fetchAll(PDO::FETCH_ASSOC);
+        }
         $statement->closeCursor();
     }
 
+    /**
+     * Fetch a record form the statement with its type data corrected
+     * Necessary to fix float data retrieved from PGSQL
+     * Returns data as an array of maps
+     * @return array
+     */
+    protected function fetchAllPgsql($statement)
+    {
+        $columnCount = $statement->columnCount();
+        $columnMeta = [];
+        for ($i = 0; $i<$columnCount; $i++) {
+            $columnMeta[$i] = $statement->getColumnMeta($i);
+        }
+
+        // Re-map fetched data using columnMeta
+        return array_map(
+            function ($rowArray) use ($columnMeta) {
+                $row = [];
+                foreach ($columnMeta as $i => $meta) {
+                    // Coerce floats from string to float
+                    // PDO PostgreSQL fails to do this
+                    if (isset($meta['native_type']) && strpos($meta['native_type'], 'float') === 0) {
+                        $rowArray[$i] = (float)$rowArray[$i];
+                    }
+                    $row[$meta['name']] = $rowArray[$i];
+                }
+                return $row;
+            },
+            $statement->fetchAll(PDO::FETCH_NUM)
+        );
+    }
+
     public function seek($row)
     {
         $this->rowNum = $row - 1;

tests/php/ORM/DatabaseTest.php

@@ -231,4 +231,38 @@ class DatabaseTest extends SapphireTest
         $this->assertInstanceOf('Exception', $ex);
         $this->assertEquals('error', $ex->getMessage());
     }
+
+
+    public function testFieldTypes()
+    {
+        // Scaffold some data
+        $obj = new MyObject();
+        $obj->MyField = "value";
+        $obj->MyInt = 5;
+        $obj->MyFloat = 6.0;
+        $obj->MyBoolean = true;
+        $obj->write();
+
+        $record = DB::prepared_query(
+            'SELECT * FROM "DatabaseTest_MyObject" WHERE "ID" = ?',
+            [ $obj->ID ]
+        )->record();
+
+        // IDs and ints are returned as ints
+        $this->assertInternalType('int', $record['ID']);
+        $this->assertInternalType('int', $record['MyInt']);
+
+        $this->assertInternalType('float', $record['MyFloat']);
+
+        // Booleans are returned as ints – we follow MySQL's lead
+        $this->assertInternalType('int', $record['MyBoolean']);
+
+        // Strings and enums are returned as strings
+        $this->assertInternalType('string', $record['MyField']);
+        $this->assertInternalType('string', $record['ClassName']);
+
+        // Dates are returned as strings
+        $this->assertInternalType('string', $record['Created']);
+        $this->assertInternalType('string', $record['LastEdited']);
+    }
 }

tests/php/ORM/DatabaseTest/MyObject.php

@@ -13,6 +13,9 @@ class MyObject extends DataObject implements TestOnly
     private static $create_table_options = array(MySQLSchemaManager::ID => 'ENGINE=InnoDB');
 
     private static $db = array(
-        'MyField' => 'Varchar'
+        'MyField' => 'Varchar',
+        'MyInt' => 'Int',
+        'MyFloat' => 'Float',
+        'MyBoolean' => 'Boolean',
     );
 }