Check if the user is logged-in in a theme

Question

In Drupal 7 we can simply check if the current user is logged-in in a theme by checking $GLOBAL['user']->uid or using user_is_logged_in().

How can I check if a user is logged-in in a page template, in Drupal 8?

A solution is to manually check in hook_preprocess_page(), but since this is very popular, I think Drupal provides something by default for the Twig theme engine.

Answer 1

If you just need to verify the current user is logged-in, you can use $variables['logged_in'], which is generally available in all the template files.

For example, the mark.html.twig file uses the following code, although the only documented variable is status.

{% if logged_in %}
  {% if status is constant('MARK_NEW') %}
    <span class="marker">{{ 'New'|t }}</span>
  {% elseif status is constant('MARK_UPDATED') %}
    <span class="marker">{{ 'Updated'|t }}</span>
  {% endif %}
{% endif %}

The variable is explicitly documented in other template files, such as html.html.twig, page.html.twig, and node.html.twig.

The variable is available in all the template files, since it is initialized in _template_preprocess_default_variables() that invokes user_template_preprocess_default_variables_alter() (an implementation of hook_template_preprocess_default_variables_alter()), which contains the following code.

  $user = \Drupal::currentUser();

  $variables['user'] = clone $user;
  // Remove password and session IDs, since themes should not need nor see them.
  unset($variables['user']->pass, $variables['user']->sid, $variables['user']->ssid);

  $variables['is_admin'] = $user->hasPermission('access administration pages');
  $variables['logged_in'] = $user->isAuthenticated();

_template_preprocess_default_variables() is called by template_preprocess(), which is the function called for theme hooks implemented as templates; this guarantees the variable is available in all the template files.

Keep in mind that macros don't have access to the current template variables, so trying to access logged_in in the code of a macro would not have any effect.
Between the template files used from Drupal core modules, the ones using a macro are:

• menu.html.twig

    {% macro menu_links(items, attributes, menu_level) %}
      {% import _self as menus %}
      {% if items %}
        {% if menu_level == 0 %}
          <ul{{ attributes }}>
        {% else %}
          <ul>
        {% endif %}
        {% for item in items %}
          <li{{ item.attributes }}>
            {{ link(item.title, item.url) }}
            {% if item.below %}
              {{ menus.menu_links(item.below, attributes, menu_level + 1) }}
            {% endif %}
          </li>
        {% endfor %}
        </ul>
      {% endif %}
    {% endmacro %}
  

• book-tree.html.twig

    {% macro book_links(items, attributes, menu_level) %}
      {% import _self as book_tree %}
      {% if items %}
        {% if menu_level == 0 %}
          <ul{{ attributes }}>
        {% else %}
          <ul>
        {% endif %}
        {% for item in items %}
          <li{{ item.attributes }}>
            {{ link(item.title, item.url) }}
            {% if item.below %}
              {{ book_tree.book_links(item.below, attributes, menu_level + 1) }}
            {% endif %}
          </li>
        {% endfor %}
        </ul>
      {% endif %}
    {% endmacro %}
  

• menu--toolbar.html.twig

    {% macro menu_links(items, attributes, menu_level) %}
      {% import _self as menus %}
      {% if items %}
        {% if menu_level == 0 %}
          <ul{{ attributes.addClass('toolbar-menu') }}>
        {% else %}
          <ul class="toolbar-menu">
        {% endif %}
        {% for item in items %}
          {%
            set classes = [
              'menu-item',
              item.is_expanded ? 'menu-item--expanded',
              item.is_collapsed ? 'menu-item--collapsed',
              item.in_active_trail ? 'menu-item--active-trail',
            ]
          %}
          <li{{ item.attributes.addClass(classes) }}>
            {{ link(item.title, item.url) }}
            {% if item.below %}
              {{ menus.menu_links(item.below, attributes, menu_level + 1) }}
            {% endif %}
          </li>
        {% endfor %}
        </ul>
      {% endif %}
    {% endmacro %}
  

For example, changing the last macro with the following code would not have the expected result.

{% macro menu_links(items, attributes, menu_level) %}
  {% import _self as menus %}
  {% if items %}
    {% if menu_level == 0 %}
      <ul{{ attributes.addClass('toolbar-menu') }}>
    {% else %}
      <ul class="toolbar-menu">
    {% endif %}
    {% for item in items %}
      {%
        set classes = [
          'menu-item',
          logged_in ? 'menu-item--logged-in-user',
          item.is_expanded ? 'menu-item--expanded',
          item.is_collapsed ? 'menu-item--collapsed',
          item.in_active_trail ? 'menu-item--active-trail',
        ]
      %}
      <li{{ item.attributes.addClass(classes) }}>
        {{ link(item.title, item.url) }}
        {% if item.below %}
          {{ menus.menu_links(item.below, attributes, menu_level + 1) }}
        {% endif %}
      </li>
    {% endfor %}
    </ul>
  {% endif %}
{% endmacro %}

Answer 2

You can with the Twig Extender module. Quote from its project page:

Add a simple plugin system to add new twig extensions (Filter and Functions). Provides a new service provider for "twig.extensions" to add new plugins.

Function: is_user_logged_in

Check if user is logged in.

{% if user_is_logged_in() %}
Hello user
{% else %}
Please login
{% endif %}

Answer 3

For everybody trying to use logged_in from menu.twig.html; you need to call it from outside the menus.menu_links() macro as the logged_in variable is out of scope within the macro.

Answer 4

You can check if the user is authenticated like so:

For example, I have created the following function in themename.theme.

# Function to get user logged info
function tropical_preprocess_page(&$variables){
  // if user is authenticated
  if($variables['user']->isAuthenticated()){
    # gets username
  $user_logged_in_name = $variables['user']->getDisplayName();
  # creates value to ouput in the DOM & capitalize first letter
  $variables['user_logged_in_name'] = ucfirst($user_logged_in_name);

  # gets user email
  $user_email = $variables['user']->getEmail();
  $variables['user_email'] = $user_email;

  // get user picture
  $user = \Drupal\user\Entity\User::load(\Drupal::currentUser()->id());
  $variables['user_picture'] = $user->get('user_picture')->entity->url();

  // Check if user is logged in
  $user_logged = $variables['user']->isAuthenticated();
  $variables['user_logged'] = $user_logged;
  }
}

After that, you can create the logic within the Twig file like so:

<div class="user-logged-greeting">
  {% if user_logged %}
    <h2>Welcome back, {{ user_logged_in_name }}!</h2>
    <p>The email for this user is: <strong>{{ user_email }}<strong></p>
    <img src="{{ user_picture }}" width="50" height="50">
  {% endif %}
</div>

If the user is logged in, you will get the greeting message along with username, email & avatar picture. If user is not logged in, it won't show up anything.

Let me know if that helps and/or if I can edit this post for better understanding.

Answer 5

The issue isn't that the variable doesn't exist in the template file, but rather that it isn't available in the macro. You can fix this via passing it through:

{% macro menu_links(items, attributes, menu_level, logged_in) %}

Then if you have a signin menu item, something like:

{% if item.title == 'Sign In' %} {% if not logged_in %} Go to login {% endif %} {% endif %}

Answer 6

I moved my login-sensitive button "Login" outside the menu macro. So the twig variable logged_in which is not in scope inside the macro could be used again.

Before moving the login-sensitive button (which did not work):

{% macro menu_links(items, attributes, menu_level) %}
  {% import _self as menus %}
  {% if items %}
    {% if menu_level == 0 %}
<ul{{ attributes.addClass('menu') }}>
  {% else %}
  <ul class="menu">
    {% endif %}
    {% for item in items %}
...
    {% endfor %}

    {% if logged_in %}
    <li class="menu-item register">
      <a href="/user" data-drupal-link-system-path="<front>" class="btn btn-light">{{ 'My user account'|t }}</a>
    </li>
    {% else %}
    <li class="menu-item register">
      <a href="/user/login" data-drupal-link-system-path="<front>" class="btn btn-light">{{ 'Login'|t }}</a>
    </li>
    {% endif %}
  </ul>

  {% endif %}
  {% endmacro %}

After moving the login-sensitive button (works for me):

{% macro menu_links(items, attributes, menu_level) %}
  {% import _self as menus %}
  {% if items %}
    {% if menu_level == 0 %}
<ul{{ attributes.addClass('menu') }}>
  {% else %}
  <ul class="menu">
    {% endif %}
    {% for item in items %}
...
    {% endfor %}
  {% endif %}
{% endmacro %}

{% if logged_in %}
  <li class="menu-item register">
    <a href="/user" data-drupal-link-system-path="<front>" class="btn btn-light">{{ 'My user account'|t }}</a>
  </li>
{% else %}
  <li class="menu-item register">
    <a href="/user/login" data-drupal-link-system-path="<front>" class="btn btn-light">{{ 'Login'|t }}</a>
  </li>
{% endif %}
</ul>