PHP: Is there a correct method for saving configuration data?

Question

I have a config.inc file in a web application that I am building. It contains an array with configuration values for things like the MySQL database, etc. I would like these to be entered by using a simple form, that asks for the server, login/password for the database, etc, then these get written to the configuration file.

Is there a preferred method of doing this? I am not sure how to write to a file, and update an array.

Answer 1

You just want writing, correct? Is it a serialized array or is it parsed?

One way to read a config file is parse_ini_file(). I wouldn't necessarily call it preferred, but it's a method. You'd still need to write the file.

Another way would to write a "config.inc.php" and just include it in, to write it you'd just output actual PHP code (e.g. $var = "myval";).

This is a way you could write a simple "output" function that took an array of configuration values and output them as name=value, assuming $config was an associative array.

foreach ($config as $name => $value) {
   $output .= $name . '=' . $value . "\n";
}

if (!file_put_contents($filename, $output)) {
    die("Error writing config file.");
}

There's a lot of decent ways to do it. It's really based on your requirements. Does it need to be in a specific format or do you have leeway?

Answer 2

It is not recommended to modify PHP configuration files via your application, you should use CSV files or a database table. In case you want to save it in a CSV file then I suggest you keep a CSV file for each configuration type (e.g CSV file for database configurations) and always overwrite the previous one using file_put_contents

Save data example:

$csvStructure = array("dbUser","dbPassword","dbHostname","dbPort"); // array used for both loading data and saving it
$csvData = array();

foreach ($csvStructure as $field) {
   $csvData[] = $_POST[$field]; // so it'd get $_POST["dbUser"],$_POST["dbPasword"], etc..
}
file_put_contents("filename",implode("\t",$csvData));

Load data example:

$csvStructure = array("dbUser","dbPassword","dbHostname","dbPort"); // array used for both loading data and saving it
$dbConfig = array();
$csvData = explode("\t",file_get_contents("filename"));    
foreach ($csvStructure as $key => $field) { // $key would have the location of the requested field in our CSV data (0,1,2, etc..).
   $dbConfig[$field] = $csvData[$key]; // populate $dbConfig["dbUser"],$dbConfig["dbPasword"], etc..
}