Caching¶

The routing library provides simple caching mechanisms for forms and data. By default, the routing library will NOT cache any forms or data.

Clearing Cache¶

To clear the cache, you can call the clear_cache function.

from routing import router
router.clear_cache()

Form Caching¶

To override the default behaviour, you can set the Route.cache_form attribute to True. This will cause the routing library to cache all forms.

from routing.router import Route
Route.cache_form = True

You can also set this attribute on specific routes.

class IndexRoute(Route):
    path = "/"
    form = "Pages.Index"
    cache_form = True

Data Caching¶

The routing library can cache data loaded by the load_data method. If you are not using the load_data method, you can skip this section. For more details, see the Data Loading section.

You can enable data caching by setting the cache_data attribute on the route to True.

Caching Keys¶

The routing library will cache forms and data using a cache key. The key is a combination of the path and the dictionary returned by the cache_deps method. By default, the cache_deps method returns the query dictionary.

Invalidating Cache¶

If you want to invalidate the cache, you can call the invalidate function. Invalidating the cache will remove data and forms from the cache.

from routing import router
router.invalidate(path="/articles")

The call signature for invalidate is:

invalidate(*, path=None, deps=None, exact=False)
invalidate(path, **kws)
invalidate(routing_context, **kws)

path

The path to invalidate.

deps

The dependencies to invalidate. These are the same dependencies that are returned by the cache_deps method.

exact

If True, then the path and deps must match exactly. If False (the default), then any path or deps that are a subset of the path and deps arguments will be invalidated.

Partial Invalidation¶

from routing.router import Route

class ArticlesRoute(Route):
    path = "/articles"
    form = "Pages.Articles"

class ArticleRoute(Route):
    path = "/articles/:id"
    form = "Pages.Article"

In the above example, if you call invalidate("/articles", exact=True), then data and forms associated with the ArticlesRoute will be invalidated. If you call invalidate("/articles", exact=False), then data and forms associated with the ArticlesRoute and all cached ArticleRoute instances will be invalidated, since the ArticleRoute path is a subset of the ArticlesRoute path.

from routing.router import Route

class ArticlesRoute(Route):
    path = "/articles"
    form = "Pages.Articles"

    def cache_deps(self, **loader_args):
        return {"page": loader_args["query"]["page"]}

    def parse_query(self, query):
        return {**query, "page": int(query.get("page", 1))}

In the above example, the data is cached depending on the page query parameter. If you call invalidate("/articles"), then all data associated with all pages will be invalidated. A deps value of {"page": 1} is considered a subset of an empty deps argument. If you call invalidate("/articles", exact=True), then no data will be invalidated, since there is no exact match. Calling invalidate("/articles", deps={"page": 1}) will invalidate only the data for the first page.

Invalidating Contexts¶

A routing context also has an invalidate method for convenience.

from routing import router

class ArticleForm(ArticleFormTemplate):
    def __init__(self, routing_context: router.RoutingContext, **properties):
        self.routing_context = routing_context
        self.init_components(**properties)

    def delete_button_click(self, **event_args):
        self.remove_from_parent()
        self.routing_context.invalidate(exact=True)