Dynamic database parameters

Yii 2.0 Tips, Snippets and Tutorials
1

(Using Yii 2.0.46) I have 2 database components, dbix and db. dbix does not change as it is used to login the user, but I want to vary the parameters of db depending on the user. I want to use Yii::$app->db etc. in my project. I can close() the connection, reassign to Yii::$app->db->dsn etc, then open() the connection with the new settings. But on the next page refresh it reverts to the settings in config[‘db’]. I am nearly there, but can anyone please help me to figure this out? Do I need to somehow override the settings in $config[‘db’]?

2

In models can define like that:

    public static function getDb()
    {
        if (\Yii::$app->user->id < 1000) {
            return \Yii::$app->db1;
        }
        return \Yii::$app->db2;
    }
3

Thank you. Yes that works, probably as \Yii::$app->db$n, but I would have to assign components db1, db2, db3…dbn in $config. What I was hoping for is a group record for each type of user with fields dsn, dbuser, dbpwd, etc from which I could generate a db component. But if your suggestion is the only way, it would work. Thanks for your reply.

4

Second solution is extend db connection component from yii\db\Connection and in constructor add logic for set dsn, username and password.

2 Likes
5

Should this no longer be “static” method?

6

Replying to my own post, I have found a solution which seems to work, by editing the entry script index.php. But I am not an expert and this takes me beyond my comfort zone. Please advise me if you see any unintended consequences or blunders…

//(new yii\web\Application($config))->run();

//Replace with this code:

$application = new yii\web\Application($config);

if (!Yii::$app->user->isGuest) {   //bypassed when user logged in
    //When user is logged in, get db params from user's group table. 
    //Put db params in config array, in session, and access it here
    $dbconfig = Yii::$app->session->get('dbconfig');
    //Add db component to main $config array
    $config['components']['db'] = $dbconfig;
    //Create application object again
    $application = new yii\web\Application($config);
}

$application->run();

Thank you for taking an interest.