WIP for a Kobold router

[fatfingers23]

TODOS

• [x] First iteration of a router that can route to a view via URL on load and get parameters from the URL
• [x] Get params from URL. Need to find a better type to store in matchit::Router<>, probably a fn -> JsValue that can take a param
• [x] Moved from Arc<Mutex<Routes>> to Rc<RefCell<Routes>>
• [x] Remove the need to mount the router multiple times to get parameter values
• [x] Move to use pushstate for routing and create navigation methods

[fatfingers23]

I have hit all the goals I had in the original draft post 🎉. At this point I have hit everything I can see for an initial router besides what is listed at the bottom. I think this is a decent start I think that can be built on. So I am going flip the PR to publish. Please let me know of any performance changes or suggestions you may have!

Implementation details and explanations

• I had initially tried saving the JsValue of the views in the matchit::Router and then conditionally rendering them out. But gave up on that because I realized it was rendering each one on the first load during the add_route method when it got the JsValue from the view.
• All routing is now handled by pushState. I also set up a custom event handler to fire off an event whenever it is called, then inside of the event handler I run whichever Fn() which is a closure to render that view Params from the URL are now loaded in the same pushstate event handler. It loads them into history.state, and then get_params reads from that. I was not able to personally find a way to completely get away from having get_params because I could not find a good way to pass them to the Fn() I am using in the matchit::Router
• The route HTML should all load into a div created on the first load with the id routerView. The idea is to have eventually a <router-view> like thing found in Vue Router. Where you can have your nav bar outside of the router-view, then as you navigate the app, it just loads what is inside of that

Current improvements I see and will look into in the future

• Unit tests
• The fence changes discussed earlier in the PR
• Better macro support where router_view! works like view!
• Keeping state between routing.
• Ability to use pushState with data that is pushed with it to send more complex data structures to routes
• Ability to pass in a custom 404 page
• Better documentation and a cleaner example
• Other performance changes: I have a few clones and Strings that I think could be better handled