next.dj
Share context across pages#
Problem#
You want to publish a value once and read it from every page below a particular directory in the route tree.
Solution#
Declare the value in a page.py that sits at the root of the subtree and pass inherit_context=True to the decorator.
Walkthrough#
Add the context function to the segment’s page.py.
from next import context
from notes.models import Note
@context("note_count", inherit_context=True)
def note_count() -> int:
return Note.objects.count()
Use the value from the layout and from any descendant page.
<header>
There are {{ note_count }} notes.
</header>
{% block template %}{% endblock template %}
The value is injected into the shared context dict for that request, so both the layout wrappers and every descendant page template can read it.
<p>{{ note_count }} notes in total.</p>
Limit inheritance to a subtree#
Drop the flag for values that should stay local to the current page only.
from next import context
@context("nav_links")
def nav_links() -> list:
return [{"label": "Home", "href": "/"}]
Without inherit_context=True the value is available only when notes/pages/page.py handles the request directly.
Descendant routes do not receive it.
A descendant page that declares the same key with its own @context overrides the inherited value for that request.
The page’s own function runs after the inherited ones, so its value wins across the whole render, layout chain included.
Verification#
Visit two pages under the directory that hosts the page.py and confirm the value renders on both.
Visit a page outside that directory and confirm the value is undefined.