Connect to MySQL database in PHP

Question

I'm trying to build a blog website.
It is deployed on Heroku and it is supposed to connect to a MySQL database. The info required to login to my database is stored in an environment variable on Heroku, and looks like this (These are fake credentials of course):

mysql://g46w916ds134b8:639f463e@us-cdbr-east-03.cleardb.net/heroku_45fab1d19h35yetf?reconnect=true

It contains the DB name, the user, the password and the host.

Is there a way to use this one string directly in my PHP code to connect to the database? I checked MySQLi and PDO documentation, and it seems like they only accept DSN/user/password or Host/user/password/DBname format.

Answer 1

<?php
$str = "mysql://g46w916ds134b8:639f463e@us-cdbr-east-03.cleardb.net/heroku_45fab1d19h35yetf?reconnect=true";
// If I correctly understanded 'mysql://login:passwd@host/dbname?some_params'
// data parsing from input string
$sp = explode('/', $str);
$sp1 = explode('@', $sp[2]);
$first_part_sp = explode(':', $sp1[0]);
$login = $first_part_sp[0];
$passwd = $first_part_sp[1];
$host = $sp1[1];
$dbname = explode('?', $sp[3])[0];
$connect_str = "mysql:host=$host;dbname=$dbname";
echo $connect_str." ".$login." ".$passwd;
// database access
$pdo = new PDO($connect_str, $user, $passwd);
?>

Answer 2

This is a url after all, so you can use parse_url function to extract data.

// Connection string from environmental variable in heroku
$connectionStringHerokuEnv = 'mysql://g46w916ds134b8:639f463e@us-cdbr-east-03.cleardb.net/heroku_45fab1d19h35yetf?reconnect=true';
$parsed = parse_url($connectionStringHerokuEnv);
$dbname = ltrim($parsed['path']. '/'); // PATH has prepended / at the beginning, it needs to be removed
// Connecting to the database
$conn = new PDO("{$parsed['scheme']}:host={$parsed};$dbname={$dbname};charset=utf8mb4", $parsed['user'], $parsed['pass'], [PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION]);

For database connection you should always use PDO and not mysqli driver. PDO allows you to connect to almost any database, without rewriting code in 85% of cases.

dont forget options [PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION] , this will allow you to catch any errors and handle them accordingly to application needs.

PDO accept this connection string driver: host=DATABASE_HOST;dbname=DATABASE_NAME; charset=DEFAULT_CHARSET(use utf8 whenever you can) driver: host=DATABASE_HOST;dbname=DATABASE_NAME; charset=DEFAULT_CHARSET(use utf8 whenever you can)

Learn more on parse_url : https://www.php.net/manual/en/function.parse-url

Learn more on PDO: https://www.php.net/manual/en/class.pdo.php