Creating custom config handlers in symfony 1.0

Romain Dorgueil — Mon, 24 Dec 2007 07:30:00 +0100

When writing plugins, you often want to do it the symfony way, by putting configuration stuff in YAML files to allow the final user to override your default values in a harmless way.

To do this, the correct way is to create a config handler, extending sfConfigHandler, or its child class sfYamlConfigHandler.

Here is a simple one, just dumping YAML data found in your config file into an sfConfig::get()-able PHP dataset.

class myStupidConfigHandler extends sfYamlConfigHandler

{

  public function execute($configFiles)

  {

    // retrieve yaml data

    $config = $this->parseYamls($configFiles);



    $code = sprintf("<?php\n" .

                    "// auto-generated by myStupidConfigHandler\n" .

                    "// date: %s\n" .

                    "sfConfig::set('my_stupid_config_entry', %s);",

                    date('Y-m-d H:i:s'), var_export($config, 1));



    return $code;

  }

}

We could enhance it a bit, to take advantage of symfony's environments and permit an 'all' (as a default section) and as many environment specific sections as you want. Here is it.

class myStupidConfigHandler extends sfYamlConfigHandler

{

  public function execute($configFiles)

  {

    // retrieve yaml data

    $config = $this->parseYamls($configFiles);



    // get current environment

    $environment = sfConfig::get('sf_environment');



    // merge default and environment specific config

    $config = sfToolKit::arrayDeepMerge(isset($config['all'])?$config['all']:array(), isset($config[$environment])?$config[$environment]:array());



    $code = sprintf("<?php\n" .

                    "// auto-generated by myStupidConfigHandler\n" .

                    "// date: %s\n" .

                    "sfConfig::set('my_stupid_config_entry', %s);",

                    date('Y-m-d H:i:s'), var_export($config, 1));



    return $code;

  }

}

Next step will be to tell symfony which configuration file patterns should be loaded using our class. To do this, add the following entry to config/config_handlers.yml (whether in your app, plugin or module, depending on the scope of your config handler)

config/stupid.yml:
  class:    myStupidConfigHandler

Once this is done, the very little remaining last step is to mak sure you include the compiled yml.php file with the following magic command, that will rebuild it when unexistant or outdated:

require_once(sfConfigCache::getInstance()->checkConfig('config/stupid.yml'));

/* ... */

$stupid_config = sfConfig::get('my_stupid_config_entry');

easy one :-)

Symfony Resources Central - how-to

Creating custom config handlers in symfony 1.0