Adding master/slave database support (Issue #6).

ChangeLog.txt

@@ -1,7 +1,7 @@
 Change Log for LEAP ORM
 
 2013-01-28
-* Changed Base_DB_ORM_Model::data_source() to Base_DB_ORM_Model::data_source($context = 0).
+* Changed Base_DB_ORM_Model::data_source() to Base_DB_ORM_Model::data_source($instance = 0).
 * Changed all instance variables $source to $data_source.
 
 2013-01-01

classes/Base/DB/DataSource.php

@@ -22,12 +22,28 @@
  *
  * @package Leap
  * @category Connection
- * @version 2013-01-26
+ * @version 2013-01-28
  *
  * @abstract
  */
 abstract class Base_DB_DataSource extends Core_Object {
 
+	/**
+	 * This constant represents a master instance of a database.
+	 *
+	 * @access public
+	 * @const integer
+	 */
+	const MASTER_INSTANCE = 0;
+
+	/**
+	 * This constant represents a slave instance of a database.
+	 *
+	 * @access public
+	 * @const integer
+	 */
+	const SLAVE_INSTANCE = 1;
+
 	/**
 	 * This variable stores the settings for the data source.
 	 *

classes/Base/DB/ORM.php

@@ -22,7 +22,7 @@
  *
  * @package Leap
  * @category ORM
- * @version 2013-01-09
+ * @version 2013-01-28
  *
  * @abstract
  */
@@ -107,7 +107,7 @@ public static function model($model, $primary_key = array()) {
 	 * @return DB_SQL_Precompiler                   an instance of the pre-compiler
 	 */
 	public static function precompiler($model) {
-		$data_source = $model::data_source();
+		$data_source = $model::data_source(DB_DataSource::MASTER_INSTANCE);
 		$precompiler = 'DB_' . $data_source->dialect . '_Precompiler';
 		$object = new $precompiler($data_source);
 		return $object;

classes/Base/DB/ORM/Delete/Proxy.php

@@ -86,7 +86,7 @@ public function __call($function, $arguments) {
 	public function __construct($model) {
 		$name = $model;
 		$model = DB_ORM_Model::model_name($name);
-		$this->data_source = new DB_DataSource($model::data_source(1));
+		$this->data_source = new DB_DataSource($model::data_source(DB_DataSource::SLAVE_INSTANCE));
 		$builder = 'DB_' . $this->data_source->dialect . '_Delete_Builder';
 		$this->builder = new $builder($this->data_source);
 		$extension = DB_ORM_Model::builder_name($name);

classes/Base/DB/ORM/Insert/Proxy.php

@@ -69,7 +69,7 @@ abstract class Base_DB_ORM_Insert_Proxy extends Core_Object implements DB_SQL_St
 	public function __construct($model) {
 		$name = $model;
 		$model = DB_ORM_Model::model_name($name);
-		$this->data_source = new DB_DataSource($model::data_source());
+		$this->data_source = new DB_DataSource($model::data_source(DB_DataSource::MASTER_INSTANCE));
 		$builder = 'DB_' . $this->data_source->dialect . '_Insert_Builder';
 		$this->builder = new $builder($this->data_source);
 		$extension = DB_ORM_Model::builder_name($name);

classes/Base/DB/ORM/MPTT.php

@@ -146,7 +146,7 @@ public function add_child($name, Array $fields = NULL) {
 			throw new Throwable_Marshalling_Exception('Message: Failed to insert record to database. Reason: Model is not insertable.', array(':class' => get_called_class()));
 		}
 
-		$data_source = static::data_source();
+		$data_source = static::data_source(DB_DataSource::MASTER_INSTANCE);
 		$table = static::table();
 
 		$connection = DB_Connection_Pool::instance()->get_connection($data_source);
@@ -243,7 +243,7 @@ public function add_child($name, Array $fields = NULL) {
 	 *                                                  node
 	 */
 	public function ancestors($ordering = 'ASC', $limit = 0, $root = TRUE) {
-		$data_source = static::data_source();
+		$data_source = static::data_source(DB_DataSource::SLAVE_INSTANCE);
 
 		$builder = DB_SQL::select($data_source)
 			->all('t1.*')
@@ -301,7 +301,7 @@ public function delete($reset = FALSE) {
 			throw new Throwable_Marshalling_Exception('Message: Failed to delete record from database. Reason: Model is not savable.', array(':class' => get_called_class()));
 		}
 
-		$data_source = static::data_source();
+		$data_source = static::data_source(DB_DataSource::MASTER_INSTANCE);
 		$table = static::table();
 
 		$connection = DB_Connection_Pool::instance()->get_connection($data_source);
@@ -496,7 +496,7 @@ public function leaves($ordering = 'ASC', $limit = 0) {
 	 * @see http://stackoverflow.com/questions/7661913/modified-preorder-tree-traversal-selecting-nodes-1-level-deep
 	 */
 	public function level() {
-		$record = DB_SQL::select(static::data_source())
+		$record = DB_SQL::select(static::data_source(DB_DataSource::SLAVE_INSTANCE))
 			->column(DB_SQL::expr('COUNT(parent_id) - 1'), 'level')
 			->from(static::table())
 			->where('scope', DB_SQL_Operator::_EQUAL_TO_, $this->fields['scope']->value)
@@ -576,7 +576,7 @@ public function save($reload = FALSE, $mode = NULL) {
 		$columns = array_keys($this->fields);
 
 		if ( ! empty($columns)) {
-			$builder = DB_SQL::update(static::data_source())
+			$builder = DB_SQL::update(static::data_source(DB_DataSource::MASTER_INSTANCE))
 				->table(static::table())
 				->where('id', DB_SQL_Operator::_EQUAL_TO_, $this->fields['id']->value);
 
@@ -683,7 +683,7 @@ public function tree() {
 	 * @return DB_ORM_MPTT                              the newly created root node
 	 **/
 	public static function add_root($scope, $name, Array $fields = NULL) {
-		$data_source = static::data_source();
+		$data_source = static::data_source(DB_DataSource::MASTER_INSTANCE);
 		$table = static::table();
 
 		$connection = DB_Connection_Pool::instance()->get_connection($data_source);

classes/Base/DB/ORM/Model.php

@@ -212,7 +212,7 @@ public function delete($reset = FALSE) {
 		if (empty($primary_key) OR ! is_array($primary_key)) {
 			throw new Throwable_Marshalling_Exception('Message: Failed to delete record from database. Reason: No primary key has been declared.');
 		}
-		$builder = DB_SQL::delete(static::data_source())->from(static::table());
+		$builder = DB_SQL::delete(static::data_source(DB_DataSource::MASTER_INSTANCE))->from(static::table());
 		foreach ($primary_key as $column) {
 			$builder->where($column, DB_SQL_Operator::_EQUAL_TO_, $this->fields[$column]->value);
 		}
@@ -328,7 +328,7 @@ public function is_relation($name) {
 	 *                                              table
 	 */
 	public function is_saved() {
-		$builder = DB_SQL::select(static::data_source())
+		$builder = DB_SQL::select(static::data_source(DB_DataSource::MASTER_INSTANCE)) // done on master instead of slave
 			->from(static::table())
 			->limit(1);
 		foreach (static::primary_key() as $column) {
@@ -367,7 +367,7 @@ public function load(Array $columns = array()) {
 			if (empty($primary_key) OR ! is_array($primary_key)) {
 				throw new Throwable_Marshalling_Exception('Message: Failed to load record from database. Reason: No primary key has been declared.');
 			}
-			$builder = DB_SQL::select(static::data_source())->from(static::table())->limit(1);
+			$builder = DB_SQL::select(static::data_source(DB_DataSource::SLAVE_INSTANCE))->from(static::table())->limit(1);
 			foreach ($primary_key as $column) {
 				$builder->where($column, DB_SQL_Operator::_EQUAL_TO_, $this->fields[$column]->value);
 			}
@@ -450,7 +450,7 @@ public function save($reload = FALSE, $mode = NULL) {
 			throw new Throwable_Marshalling_Exception('Message: Failed to save record to database. Reason: No primary key has been declared.');
 		}
 
-		$data_source = static::data_source();
+		$data_source = static::data_source(DB_DataSource::MASTER_INSTANCE);
 		$table = static::table();
 		$columns = array_keys($this->fields);
 		$hash_code = $this->hash_code();
@@ -671,11 +671,11 @@ public static function columns() {
 	 *
 	 * @access public
 	 * @static
-	 * @param integer $context                      the data source context to be used (e.g.
+	 * @param integer $instance                     the data source instance to be used (e.g.
 	 *                                              0 = master, 1 = slave, 2 = slave, etc.)
 	 * @return string                               the data source name
 	 */
-	public static function data_source($context = 0) {
+	public static function data_source($instance = 0) {
 		return 'default'; // the key used in config/database.php
 	}
 

classes/Base/DB/ORM/Relation/BelongsTo.php

@@ -69,7 +69,7 @@ protected function load() {
 		$parent_model = $this->metadata['parent_model'];
 		$parent_table = $parent_model::table();
 		$parent_key = $this->metadata['parent_key'];
-		$parent_source = $parent_model::data_source();
+		$parent_source = $parent_model::data_source(DB_DataSource::SLAVE_INSTANCE);
 
 		$child_key = $this->metadata['child_key'];
 

classes/Base/DB/ORM/Relation/HasMany.php

@@ -86,13 +86,13 @@ protected function load() {
 		$child_model = $this->metadata['child_model'];
 		$child_table = $child_model::table();
 		$child_key = $this->metadata['child_key'];
-		$child_source = $child_model::data_source();
+		$child_source = $child_model::data_source(DB_DataSource::SLAVE_INSTANCE);
 
 		if (isset($this->metadata['through_model']) AND isset($this->metadata['through_keys'])) {
 			$through_model = $this->metadata['through_model'];
 			$through_table = $through_model::table();
 			$through_keys = $this->metadata['through_keys'];
-			$through_source = $through_model::data_source();
+			$through_source = $through_model::data_source(DB_DataSource::SLAVE_INSTANCE);
 
 			if ($through_source != $child_source) {
 				$builder = DB_SQL::select($through_source)

classes/Base/DB/ORM/Relation/HasOne.php

@@ -71,7 +71,7 @@ protected function load() {
 		$child_model = $this->metadata['child_model'];
 		$child_table = $child_model::table();
 		$child_key = $this->metadata['child_key'];
-		$child_source = $child_model::data_source();
+		$child_source = $child_model::data_source(DB_DataSource::SLAVE_INSTANCE);
 
 		$builder = DB_SQL::select($child_source)
 			->all("{$child_table}.*")

classes/Base/DB/ORM/Select/Proxy.php

@@ -103,7 +103,7 @@ public function __call($function, $arguments) {
 	public function __construct($model, Array $columns = array()) {
 		$name = $model;
 		$model = DB_ORM_Model::model_name($name);
-		$this->data_source = new DB_DataSource($model::data_source());
+		$this->data_source = new DB_DataSource($model::data_source(DB_DataSource::SLAVE_INSTANCE));
 		$builder = 'DB_' . $this->data_source->dialect . '_Select_Builder';
 		$this->table = $model::table();
 		$this->builder = new $builder($this->data_source, $columns);

classes/Base/DB/ORM/Update/Proxy.php

@@ -86,7 +86,7 @@ public function __call($function, $arguments) {
 	public function __construct($model) {
 		$name = $model;
 		$model = DB_ORM_Model::model_name($name);
-		$this->data_source = new DB_DataSource($model::data_source());
+		$this->data_source = new DB_DataSource($model::data_source(DB_DataSource::MASTER_INSTANCE));
 		$builder = 'DB_' . $this->data_source->dialect . '_Update_Builder';
 		$this->builder = new $builder($this->data_source);
 		$extension = DB_ORM_Model::builder_name($name);

classes/Base/Model/Leap/Role.php

@@ -68,11 +68,11 @@ public function __construct() {
 	 * @access public
 	 * @override
 	 * @static
-	 * @param integer $context                      the data source context to be used (e.g.
+	 * @param integer $instance                     the data source instance to be used (e.g.
 	 *                                              0 = master, 1 = slave, 2 = slave, etc.)
 	 * @return string                               the data source name
 	 */
-	public static function data_source($context = 0) {
+	public static function data_source($instance = 0) {
 		return 'default';	
 	}
 

classes/Base/Model/Leap/Session.php

@@ -58,11 +58,11 @@ public function __construct() {
 	 * @access public
 	 * @override
 	 * @static
-	 * @param integer $context                      the data source context to be used (e.g.
+	 * @param integer $instance                     the data source instance to be used (e.g.
 	 *                                              0 = master, 1 = slave, 2 = slave, etc.)
 	 * @return string                               the data source name
 	 */
-	public static function data_source($context = 0) {
+	public static function data_source($instance = 0) {
 		return 'default';	
 	}
 

classes/Base/Model/Leap/User.php

@@ -163,11 +163,11 @@ public function complete_login() {
 	 * @access public
 	 * @override
 	 * @static
-	 * @param integer $context                      the data source context to be used (e.g.
+	 * @param integer $instance                     the data source instance to be used (e.g.
 	 *                                              0 = master, 1 = slave, 2 = slave, etc.)
 	 * @return string                               the data source name
 	 */
-	public static function data_source($context = 0) {
+	public static function data_source($instance = 0) {
 		return 'default';	
 	}
 

classes/Base/Model/Leap/User/Role.php

@@ -70,11 +70,11 @@ public function __construct() {
 	 * @access public
 	 * @override
 	 * @static
-	 * @param integer $context                      the data source context to be used (e.g.
+	 * @param integer $instance                     the data source instance to be used (e.g.
 	 *                                              0 = master, 1 = slave, 2 = slave, etc.)
 	 * @return string                               the data source name
 	 */
-	public static function data_source($context = 0) {
+	public static function data_source($instance = 0) {
 		return 'default';
 	}
 

classes/Base/Model/Leap/User/Token.php

@@ -91,7 +91,7 @@ public function create_token() {
 		do {
 			$token = sha1(uniqid(Text::random('alnum', 32), TRUE));
 		}
-		while(DB_SQL::select($this->data_source())->from($this->table())->where('token', DB_SQL_Operator::_EQUAL_TO_, $token)->query()->is_loaded());
+		while(DB_SQL::select($this->data_source(DB_DataSource::SLAVE_INSTANCE))->from($this->table())->where('token', DB_SQL_Operator::_EQUAL_TO_, $token)->query()->is_loaded());
 		return $token;
 	}
 
@@ -101,11 +101,11 @@ public function create_token() {
 	 * @access public
 	 * @override
 	 * @static
-	 * @param integer $context                      the data source context to be used (e.g.
+	 * @param integer $instance                     the data source instance to be used (e.g.
 	 *                                              0 = master, 1 = slave, 2 = slave, etc.)
 	 * @return string                               the data source name
 	 */
-	public static function data_source($context = 0) {
+	public static function data_source($instance = 0) {
 		return 'default';
 	}