b7baf632c0
This is a major refactor of how the router previously worked. There are a couple major advantages of this refactor, and future work will be built on top of it. First, we will no longer have multiple navigations running at the same time. Previously, a new navigation wouldn't cause the old navigation to be cancelled and cleaned up. Instead, multiple navigations could be going at once, and we imperatively checked that we were operating on the most current `router.navigationId` as we progressed through the Observable streams. This had some major faults, the biggest of which was async races where an ongoing async action could result in a redirect once the async action completed, but there was no way to guarantee there weren't also other redirects that would be queued up by other async actions. After this refactor, there's a single Observable stream that will get cleaned up each time a new navigation is requested. Additionally, the individual pieces of routing have been pulled out into their own operators. While this was needed in order to create one continuous stream, it also will allow future improvements to the testing APIs as things such as Guards or Resolvers should now be able to be tested in much more isolation. * Add the new `router.transitions` observable of the new `NavigationTransition` type to contain the transition information * Update `router.navigations` to pipe off of `router.transitions` * Re-write navigation Observable flow to a single configured stream * Refactor `switchMap` instead of the previous `mergeMap` to ensure new navigations cause a cancellation and cleanup of already running navigations * Wire in existing error and cancellation logic so cancellation matches previous behavior PR Close #25740
Angular Router
Managing state transitions is one of the hardest parts of building applications. This is especially true on the web, where you also need to ensure that the state is reflected in the URL. In addition, we often want to split applications into multiple bundles and load them on demand. Doing this transparently isn’t trivial.
The Angular router is designed to solve these problems. Using the router, you can declaratively specify application state, manage state transitions while taking care of the URL, and load components on demand.
Overview
Read the overview of the Router here.
Guide
Read the dev guide here.
Local development
# keep @angular/router fresh
$ ./scripts/karma.sh
# keep @angular/core fresh
$ ../../../node_modules/.bin/tsc -p modules --emitDecoratorMetadata -w
# start karma
$ ./scripts/karma.sh