Mysqli Error 2002: no such file or directory [duplicate] - php

Question

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Celery workers unable to connect to redis on docker instances
(3 answers)
Closed 5 years ago.
I am trying to run nginx, php, mysql together with docker.
When i run docker-compose, everything looks fine, but when i try to make a connection to mysql via php code in my index page i'm getting this error.
Warning: mysqli::__construct(): (HY000/2002): No such file or directory in /code/index.php on line 8
Connection failed: No such file or directory
I have tried changing localhost to 127.0.0.1 and both with :3306 after it.
When changing localhost --> 127.0.0.1, i'm getting another connection failed statement:
Warning: mysqli::__construct(): (HY000/2002): Connection refused in /code/index.php on line 8
Connection failed: Connection refused
php code:
<?php
$servername = "localhost";
$username = "root";
$password = "toor";
// Create connection
$conn = new mysqli($servername, $username, $password);
// Check connection
if ($conn->connect_error) {
die("Connection failed: " . $conn->connect_error);
}
echo "Connected successfully";
echo phpinfo();
?>
Also when i look at phpinfo();, there is no value given to mysqli.default_socket.
when going into the mysql image after starting docker-compose, i'm able to go into mysql shell and execute commands just fine.
Any help is appreciated!

Answer 1

Read my answer from this other question. Localhost doesn't resolve like you think it should inside a container.
When you use a docker-compose.yml, you can reference the other services by their service name as specified in the docker-compose.yml. Your hostnames are not localhost, rather they are web, php, and mysql. So in your php code, you should use $servername = "mysql"; instead of $servername = "localhost";