What's Is the Best File Format for Configuration Files

Question

I am creating a framework in PHP and need to have a few configuration files. Some of these files will unavoidably have a large number of entries.

What format would be the best for these config files?

Here is my quantification of best:

1. Easily parsed by PHP. It would be nice if I didn't have to write any parsing code but this is not a deal breaker.
2. Remains easily read by humans even when there are a large amount of entries
3. Is a widely used standard, no custom formats
4. Succinctness is appreciated

I started out using XML, but quickly gave up for obvious reasons. I've thought of JSON and YAML but wanted to see what else is out there.

Answer 1

How about an INI file format? It's a de facto configuration file standard, and PHP has a built-in parser for that format:

parse_ini_file

Answer 2

YAML is a good option: http://www.yaml.org/

It's very simple and powerful, too

Ruby projects use it a lot for configuration.

Answer 3

Why don´t you use a PHP file for the configuration?

The benefits are clear:

• possible errors will get caught automatically
• no need to use/create a custom parser
• it´s widely understood by PHP programmers
• you can have some custom logic, for example using custom configurations for development, others for production, etc

Other frameworks like Django and rails use a config file which is a script.

Answer 4

Another option would be to use JSON and use json_encode and json_decode.

You would be able to use richer data structures in your configuration parameters.

Answer 5

Personly I like to do config data in a class.

class appNameConfig {
    var $dbHost = 'localhost';
    var $dbUser = 'root';
    //...
 }

then to use them all you have to do is

$config = new appNameConfig;
mysql_connect($config->dbHost, $config->dbUser, $config->dbPassword) or die(/*...*/);

to change the config all you have to do is read the file with the class in it I use a function like this:

function updateConfig($parameter, $value) {
    $fh = fopen('config.php', 'w+');
    while(!feof($fh)) {
        $file .= fgets($fh);
     }
    $fileLines = explode("\n", $file);
    for($i=0;$i<count($fileLines);$i++) {
        if(strstr($fileLines[$i], $parameter)) {
            $fileLines[$i] = "$" . $parameter . " = '" . $value . "'";
         }
     }
    $file = implode("\n", $fileLines);
    fwrite($fh, $file);
    fclose($fh);
 }