database.php

<?php

/**
  * Cake database configuration for git repositories.
  *
  * It automatically detects the current working branch and uses the appropriate database connection.
  * Fallback is given by the "default" entry.
  */
class DATABASE_CONFIG {
    /**
     * Fallback database connection for any branch that has no explicit config.
     * e.g. "master" branch
     */
    public $default = array();

    /**
     * Database connection for "stable" branch.
     */
    public $stable = array();

    /**
     * Test database connection for "stable" branch.
     */
    public $stable_test = array();

    /**
     * Database connection for branch: "another_branch".
     */
    public $another_branch = array();

    /**
     * Test database connection for "another_branch" branch.
     */
    public $another_branch_test = array();

    /**
     * Database connection for test suite. (from cake conventions)
     */
    public $test_suite = array();

    public function __construct() {
        $git_branch_info = exec('git branch | grep "*"');
        $matches = array();        
        preg_match('/\* (.+)$/', $git_branch_info, $matches);
        $branch = $matches[1];
        
        if (isset($this->{$branch})) {
            $this->default = array_merge($this->default, $this->{$branch});

            $branch_test = $branch . '_test';
            $this->test_suite = array_merge($this->test_suite, $this->{$branch_test});
        }
    }
}