How can I read Yaml files?

Question

I have been trying to figure out how to decode ( also try to encode) my YML file so I can have full control over on PHP array. I try this...

And as you can see, I did not get the information inside of the YML file.

My question is what I'm doing wrong ? Why is not showing me the information inside of /core/modules/toolbar/toolbar.breakpoints.yml file?

Here is code snippet...

use Drupal\Component\Serialization\Yaml;

$breakpointEncoded = Yaml::encode('/core/modules/toolbar/toolbar.breakpoints.yml');
var_dump($breakpointEncoded);

Answer 1

The arg to decode is:

The raw data string to decode

So you need (e.g.):

$breakpointEncoded = Yaml::decode(file_get_contents('/PATH/TO/core/modules/toolbar/toolbar.breakpoints.yml'));

Answer 2

You can use the Symfony component as well in Drupal 8:

use Symfony\Component\Yaml\Yaml;    

$file_path = DRUPAL_ROOT . '/core/modules/toolbar/toolbar.breakpoints.yml';
$file_contents = file_get_contents($file_path);
$ymldata = Yaml::parse($file_contents);

Answer 3

Even simplier now with a one-liner on Drupal 8.9 (the decode function has been removed from the Yaml Symfony Dependency utility class) :

use Symfony\Component\Yaml\Yaml; 

$ymldata = Yaml::parseFile(DRUPAL_ROOT . '/core/modules/toolbar/toolbar.breakpoints.yml');