Ajout d’un template tag "canonical_url" (numerique-gouv#309)

* New  template tag

* Fix URL

Author: Ash-Crow

config/settings.py

@@ -37,6 +37,7 @@
 
 ALLOWED_HOSTS = os.getenv("ALLOWED_HOSTS", "127.0.0.1,.localhost").replace(" ", "").split(",")
 
+HOST_PROTO = os.getenv("HOST_PROTO", "https")
 HOST_URL = os.getenv("HOST_URL", "localhost")
 
 INTERNAL_IPS = [
@@ -266,7 +267,7 @@ def show_toolbar(request):
 
 # Base URL to use when referring to full URLs within the Wagtail admin backend -
 # e.g. in notification emails. Don't include '/admin' or a trailing slash
-WAGTAILADMIN_BASE_URL = f"{os.getenv('HOST_PROTO', 'https')}://{HOST_URL}"
+WAGTAILADMIN_BASE_URL = f"{HOST_PROTO}://{HOST_URL}"
 
 HOST_PORT = os.getenv("HOST_PORT", "")
 if HOST_PORT != "":

content_manager/templatetags/wagtail_dsfr_tags.py

@@ -3,6 +3,7 @@
 from django.conf import settings
 from django.template.context import Context
 from django.utils.html import mark_safe
+from wagtail.models import Site
 from wagtail.rich_text import RichText
 
 from content_manager.models import MegaMenu
@@ -25,6 +26,29 @@ def settings_value(name):
     return getattr(settings, name, "")
 
 
+@register.simple_tag(takes_context=True)
+def canonical_url(context):
+    """
+    Make the best effort to get a canonical URL for the current page, considering that:
+    - Multiple schemes can be allowed (http vs https), but only one should be canonical
+    - Sites can answer to multiple URLs, but only one should be canonical
+    - Multiple sites can exist on the same instance
+    - Some pages are not instances of Wagtail Pages (eg. search results, 404, etc.)
+    """
+    request = context["request"]
+    scheme = settings.HOST_PROTO
+    site = Site.find_for_request(request)
+
+    if site:
+        hostname = site.hostname
+        if site.port != 80:
+            hostname = f"{hostname}:{site.port}"
+    else:
+        hostname = request.get_host
+
+    return f"{scheme}://{hostname}{request.path}"
+
+
 @register.filter
 def richtext_p_add_class(value, class_name: str):
     """

templates/base.html

@@ -1,4 +1,4 @@
-{% load i18n static dsfr_tags wagtailuserbar wagtailsettings_tags sass_tags %}
+{% load i18n static dsfr_tags wagtailuserbar wagtailsettings_tags sass_tags wagtail_dsfr_tags %}
 
 {% get_settings %}
 {% with SiteConfig=settings.content_manager.CmsDsfrConfig %}
@@ -19,6 +19,10 @@
       {% block description %}
       {% endblock description %}
 
+      {% block canonical_url %}
+        <link rel="canonical" href="{% canonical_url %}" />
+      {% endblock canonical_url %}
+
       {% dsfr_favicon %}
 
       {% dsfr_css %}