From 342ada2451418a3f4eb4def44a2909c84a075e98 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jaime=20Z=C3=BA=C3=B1iga?= <jaime.ziga@gmail.com>
Date: Fri, 19 Jul 2024 23:29:10 -0600
Subject: [PATCH] Added core and database configuration examples.

---
 Config/core.php     |   9 +++
 Config/database.php | 139 ++++++++++++++++++++++++++++++++++++++++++++
 README.md           |  27 ++++++++-
 3 files changed, 173 insertions(+), 2 deletions(-)
 create mode 100644 Config/core.php
 create mode 100644 Config/database.php

diff --git a/Config/core.php b/Config/core.php
new file mode 100644
index 0000000..bc7d39d
--- /dev/null
+++ b/Config/core.php
@@ -0,0 +1,9 @@
+<?php
+
+/*
+ * Includes Core Datasource Database classes path.
+ * This path is needed so as to extend the default MySQL Database class (DboDatasource adapter).
+ * This class is needed for MySQLReplica class, said class can switch between Source database
+ * and Replica database.
+ */
+App::build(['Model/Datasource/Database' => App::core('Datasource/Database')]);
diff --git a/Config/database.php b/Config/database.php
new file mode 100644
index 0000000..1ae1afa
--- /dev/null
+++ b/Config/database.php
@@ -0,0 +1,139 @@
+<?php
+/**
+ * DATABASE CONFIG.
+ */
+class DATABASE_CONFIG
+{
+	/**
+	 * CakePHP's Database Config Default Schema.
+	 *
+	 * @var array
+	 */
+	protected $base_config = [
+			'datasource' => 'Database/Mysql',
+			'persistent' => false,
+			'host'       => null,
+			'login'      => null,
+			'password'   => null,
+			'port'       => null,
+			'database'   => null,
+			'encoding'   => null,
+			'prefix'     => null,
+			'ssl_ca'     => null,
+	];
+
+	/**
+	 * Default DataSource.
+	 *
+	 * @var string
+	 */
+	protected $default_datasource = 'Database/Mysql';
+
+	/**
+	 * Replication DataSource.
+	 *
+	 * @var string
+	 */
+	protected $replica_datasource = 'Database/MysqlReplica';
+
+	/**
+	 * Datasource in use.
+	 *
+	 * @var string
+	 */
+	protected $datasource = 'Database/Mysql';
+
+	/**
+	 * Use of Replication flag.
+	 *
+	 * @var string
+	 */
+	protected $replication = false;
+
+	/**
+	 * Source database.
+	 *
+	 * @var array
+	 */
+	public $source = null;
+
+	/**
+	 * Replica databases.
+	 *
+	 * @var array
+	 */
+	public $replicas = null;
+
+	/**
+	 * Sets the database configuration for MySQL Replication.
+	 *
+	 * @return void
+	 */
+	public function __construct()
+	{
+		$this->replication = false;
+		$this->datasource  = $this->default_datasource;
+		$this->base_config = array_merge($this->base_config, ['datasource' => $this->datasource]);
+
+		/*
+		 * Assuming your database configuration is an assoc array
+		 * having 'source' as an array and 'replicas' as an array of arrays
+		 * with $this->base_config structure.
+		 */
+		$database = Configure::read('database');
+
+		// Source will Read and Write when not in replication mode.
+		$this->setSource($database['source']);
+		$this->default = $this->source;
+
+		// If there are replicas we can then enable replication mode.
+		if ((array) $database['replicas'])
+		{
+			$this->replication = true;
+
+			/*
+			 * For Source-Replica configuration, set datasource to MysqlReplica
+			 * so as to make it possible to switch between Source and Replica servers.
+			 */
+			$this->datasource = $this->replica_datasource;
+			$this->base_config = array_merge($this->base_config, ['datasource' => $this->datasource]);
+
+			$this->setSource($database['source']);
+			$this->setReplicas($database['replicas']);
+
+			// Assign a random replica for the Read transactions, overrides previous setting.
+			if ($this->replicas)
+			{
+				$this->default = $this->replicas[rand(0, count($this->replicas) - 1)];
+			}
+		}
+	}
+
+	/**
+	 * Set source database configuration.
+	 *
+	 * @param  array $source Source database configuration.
+	 * @return void
+	 */
+	private function setSource($source)
+	{
+		// Source can Read and Write.
+		$this->source = array_merge($this->base_config, (array) $source);
+	}
+
+	/**
+	 * Set replicas database configuration.
+	 *
+	 * @param  array $replicas An array of replica database configurations.
+	 * @return void
+	 */
+	private function setReplicas($replicas)
+	{
+		// Replicas can only Read.
+		$this->replicas = [];
+		foreach ((array) $replicas as $replica)
+		{
+			$this->replicas[] = array_merge($this->base_config, $replica);
+		}
+	}
+}
diff --git a/README.md b/README.md
index 08b4cad..e3d9448 100644
--- a/README.md
+++ b/README.md
@@ -1,2 +1,25 @@
-# CakeReplication
-CakePHP for MySQL Replication
+# CakePHP Replication for MySQL
+CakeReplication helps you setup CakePHP 2.10 (latest and last) Replication for MySQL 5.7 in a more integrated way  
+adding a layer between Model and the MySQL default driver.
+
+## Requirements
+* PHP `7.1.4`
+* CakePHP `2.10.4`
+* MySQL `5.7`
+* Updating your `app/Config/database.php`
+
+*There are other versions of this implementation but are quite outdated, made for older CakePHP versions that*  
+*have missmatching class methods and arguments.*
+
+## Installation
+Install the Plugin with [Composer](https://getcomposer.org) from your CakePHP's ROOT directory.
+
+```
+ $ composer require --dev adrian0350/cakephp-replication 
+```
+\
+Add CakePHP's datasource Database `core` `path` to your `app/Config/core.php`.
+
+````
+ App::build(['Model/Datasource/Database' => App::core('Datasource/Database')]);
+````