Symfony News

New in Symfony 3.1: YAML deprecations

Christian Flothmann

Contributed by
Christian Flothmann
in #17462, #17809 and #17746.

In Symfony 2.8 we introduced some YAML deprecations to make configuration files compliant with the YAML spec. In Symfony 3.1 we introduced additional deprecations, some of them needed for the new YAML features which will be explained in an upcoming article.

Deprecated the !!php/object tag

The values of the YAML properties can be serialized PHP objects thanks to the special !!php/object tag:

1
2
3
# app/config/config.yml
parameters:
    my_object: '!!php/object:O:27:"AppBundle\Service\MyService":1:{s:1:"b";s:3:"foo";}'

In Symfony 3.1 we deprecated the !!php/object tag in favor of the new !php/object tag, which is almost identical but it's prefixed with just one ! character:

1
2
3
# app/config/config.yml
parameters:
    my_object: '!php/object:O:27:"AppBundle\Service\MyService":1:{s:1:"b";s:3:"foo";}'

Deprecated the Dumper::setIndentation() method

When using the Yaml component independently from the Symfony framework, you may have used the setIndentation() method to set the number of white spaces added on each indentation level (which is 4 by default).

1
2
3
4
use Symfony\Component\Yaml\Dumper;

$yaml = new Dumper();
$yaml->setIndentation(2);

In Symfony 3.1 this method is deprecated and it will be removed in Symfony 4.0. Instead, set the indentation level as the constructor argument:

1
2
3
use Symfony\Component\Yaml\Dumper;

$yaml = new Dumper(2);

Deprecated starting scalars with % characters

This deprecation will certainly affect all of your Symfony applications. If you open your YAML configuration files, you'll find some values enclosed with % characters, which means that they are Symfony container parameters:

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
framework:
    secret:       %secret%
    router:
        resource: %kernel.root_dir%/config/routing.yml
        # ...
    default_locale:  %locale%

twig:
    debug:            %kernel.debug%
    strict_variables: %kernel.debug%
    # ...

In Symfony 3.1, the usage of % at the beginning of an unquoted string is deprecated and it will be removed in Symfony 4.0. The solution is simple but a bit tiresome: wrap these strings with single or double quotes:

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
framework:
    secret:       '%secret%'
    router:
        resource: '%kernel.root_dir%/config/routing.yml'
        # ...
    default_locale:  '%locale%'

twig:
    debug:            '%kernel.debug%'
    strict_variables: '%kernel.debug%'
    # ...
Be trained by Symfony experts - 2016-04-22 Clichy - 2016-04-26 London - 2016-04-26 London


Source: https://symfony.com/blog

About us

What a Symfony developer should know about the framework: News, Jobs, Tweets, Events, Videos,...

Resources

Find us on Twitter

Find us on Facebook