How to use Mysql Connection String inside PHP code which is served by Azure Lunix App Service

I’m trying to host WordPress to Azure lunix App service.

I created a Azure Database for MySQL, then I got the web app connection string from the connection strings screen.

The connection string format is

Database={your_database}; Data Source={data_source}; User Id= {user_id}; Password={your_password}

Then I created a Linux based app service and added the MySQL connection string to its configuration.

Then I used this code in wp-config.php to get the Database connection string form the PHP environment variable MYSQLCONNSTR_bridgesConnection

<?php

$connectstr_dbhost = '';
$connectstr_dbname = '';
$connectstr_dbusername = '';
$connectstr_dbpassword = '';

foreach ($_SERVER as $key => $value) {
    echo $key ;
 if (strpos($key, "MYSQLCONNSTR_bridgesConnection") !== 0) {
 continue;
 }


 $connectstr_dbhost = preg_replace("/^.*Data Source=(.+?);.*$/", "\1", $value);
 $connectstr_dbname = preg_replace("/^.*Database=(.+?);.*$/", "\1", $value);
 $connectstr_dbusername = preg_replace("/^.*User Id=(.+?);.*$/", "\1", $value);
 $connectstr_dbpassword = preg_replace("/^.*Password=(.+?)$/", "\1", $value);
}

That code works if you are using windows App service. But If you are using Linux App service you will get this warning and the wordpress won’t work

Warning: mysqli_real_connect(): (HY000/2002): No such file or directory in /wordpress/wp-includes/wp-db.php on line 1452

I created a php info page using this code

<?php
phpinfo();
?>

I’m sure that the PHP environment variable is loaded but I need a way to access it.

How to access that connection string in PHP code?

Answer

After very long search I found the only way to do that is to use getenv function.

The final code in wp-config.php would be:

$connectstr_dbhost = '';
$connectstr_dbname = '';
$connectstr_dbusername = '';
$connectstr_dbpassword = '';

$value = getenv('MYSQLCONNSTR_bridgesConnection');

 $connectstr_dbhost = preg_replace("/^.*Data Source=(.+?);.*$/", "\1", $value);
 $connectstr_dbname = preg_replace("/^.*Database=(.+?);.*$/", "\1", $value);
 $connectstr_dbusername = preg_replace("/^.*User Id=(.+?);.*$/", "\1", $value);
 $connectstr_dbpassword = preg_replace("/^.*Password=(.+?)$/", "\1", $value);


// ** MySQL settings - You can get this info from your web host ** //
/** The name of the database for WordPress */
define('DB_NAME', $connectstr_dbname);

/** MySQL database username */
define('DB_USER', $connectstr_dbusername);

/** MySQL database password */
define('DB_PASSWORD', $connectstr_dbpassword);

/** MySQL hostname : this contains the port number in this format host:port . Port is not 3306 when using this feature*/
define('DB_HOST', $connectstr_dbhost);