How can I define global variables inside a twig template file?

Question

Is it possible to set global variables in a twig file, so that I can access that variables from other files, macros and blocks.

For example, I want to have variables.twig file and in it set my variables and then I can include it in other templates.

I know that setting global variables is possible from the framework (e.g. Symfony) but I want a solution using twig features only.

Answer 1

Using Symfony configuration

If you are using Symfony2+, you can set globals in your config.yml file:

# app/config/config.yml
twig:
    # ...
    globals:
        myStuff: %someParam%

And then use {{ myStuff }} anywhere in your application.

---

Using Twig_Environment::addGlobal

If you are using Twig in another project, you can set your globals directly in the environment:

$twig = new Twig_Environment($loader);
$twig->addGlobal('myStuff', $someVariable);

And then use {{ myStuff }} anywhere in your application.

---

Using a Twig template

When you're including a piece of Twig code, you're only including the rendered view coming from that code, not the code itself. So it is by design not possible to include a set of variables the way you are looking for.

Answer 2

Since Symfony 4, the you can set the globals in config/packages/twig.yaml.

# config/packages/twig.yaml
twig:
    # ...
    globals:
        ga_tracking: 'UA-xxxxx-x'