Add useRouter() hook and update Router.onChange

[toniopelo]

Fixes #339

This PR adds the useRouter() hook that leverage preact useContext().

Usage:

const [
    {
        router,
        url,
        previous,
        active,
        current,
        path,
        matches
    },
    route,
] = useRouter()

This PR also adds path and matches to the onChange Router callback.

[toniopelo]

I reversed the tuple values order in the useRouter() return so it is compliant with the expected form of hook return ([value, setValue]). Seemed a better choice.

Any thoughts on this @developit ?

[toniopelo]

Sorry to bother you again @developit, but would you mind take a look at this one ?
This is working on my project since a few month already, seems all fine.

[toniopelo]

Up @developit 🌱 👁️

[toniopelo]

Update: Adding a parameter to useRouter() to allow typing the url parameters concerning the route or set of routes your component is in.
If not given, this defaults to the original value

const [{ matches }] = useRouter<{id: string}>()
matches.id // matches is typed as { id: string }

cc @developit

[toniopelo]

@prateekbh Do you have any idea of somebody I could ping for this to be reviewed ?

[developit]

Hiya! Sorry for the super long wait time on this - I'd read the PR and was noodling on what to do.

Two things on my mind:

1. originally I was thinking we should avoid hooks here and tell folks to use something like wouter, but given how straightforward this PR makes things, I'm okay with merging it.

2. I wonder if, because hooks is a separate library, this would make more sense to export from preact-router/match?

For the second one, it might actually be a really nice way to get rid of the global subscriptions / Router.subscriptions. match/src/index.js could be simplified to:

import { h, Component } from 'preact';
import { useContext } from 'preact/hooks';
import { Link as StaticLink, exec } from 'preact-router';

/** imagine your useRouter implementation here */

// this was previously 24 lines of code! yay
export function Match(props) {
	const { url, path } = useRouter()[0];
	const matches = exec(path, props.path, {}) !== false;
	return props.children({ url, path, matches });
}

// Link becomes simpler too! and is no longer global
export function Link({ class: c, className, activeClass, activeClassName, path, ...props }) {
	const inactive = [c, className].filter(Boolean).join(' ');
	const active = [c, className, activeClass, activeClassName].filter(Boolean).join(' ');
	const path = useRouter()[0].path;
	const matches = exec(path, props.path, {}) !== false;
	return <StaticLink {...props} class={matches ? active : inactive} />;
}

export default Match;

[developit]

Ah I also thought of one more thing while writing the above - it might be super useful to allow passing a path to useRouter():

function Foo() {
  const [{ path, url, matches }] = useRoute('/profile/:username');
  if (matches) {
    return <Profile username={matches.username} />;
  }
  return <Homepage />;
}

(or maybe this would just be a second hook we could provide?)

[toniopelo]

Hi @developit!

Thanks for the review and I'm glad that this convinced you to merge it :)
I've applied your suggestions to simplify Match and Link components and got rid of the global Router.subscriptions 🎉

Concerning the useRouter hook being exported from preact-router/match, I first was trying to imagine a good way to achieve that. As the RouterContext, on which the hook value depends, is really tied to the core router, I figured out I would keep the context in the core package and export it from there, I would then import and use it within preact-router/match.
My try is here

useRouter() always return the inital value of the hook, probably because it keeps a copy of the context when the module is first exported/imported and does not point to the same object reference

I might be missing something there, don't hesitate to share your thoughts.

---

Concerning the possibility to pass a path to useRouter('/my/path/:param').
I guess the goal is to reproduce the Match use case. I think it's a good idea, but I would be more comfortable having matches always being the params of the current route and having another props returned like isMatch that would be a boolean that replicate the Match behavior in case you pass a path to the hook.

Or we could have another useMatch hook instead...
What do you think ?

[toniopelo]

Up @developit 😁

[toniopelo]

🎰 😄 @developit
(FYI, I do use this in production for a while now, seems fine).

[toniopelo]

@developit 👋 😄

[toniopelo]

Would be great to have this merged @developit, if this is okay and because this has been a very long time this PR is opened, I think discussions about enhancing this feature can take place elsewhere after this is merged. Would you agree ?

[toniopelo]

@developit I don't know what to do apart from notifying you again, so I notify you again.

[toniopelo]

@prateekbh Do you see any way to have this merged ?

[toniopelo]

This is frustrating.
cc @developit @prateekbh

[marvinhagemeister]

This is fantastic! 🙌

[prateekbh]

Wow the hook has landed! Fantastic work here @toniopelo 🎉

[toniopelo]

Thanks a lot @marvinhagemeister and @prateekbh, feels good to have this merged finally 😛 💪

[felipeloge]

Hey guys, I see the PR is merged but there isn't any new release/tag version. So are we going to have a new release version to use this new useRouter hook?

[toniopelo]

@marvinhagemeister Any plan on releasing this soon on npm ?

[toniopelo]

@marvinhagemeister @developit Up, could this be released ?

[toniopelo]

@prateekbh @developit @marvinhagemeister @masteroftheentireworldandtheuniverse Please, do something, I'm getting really tired with this situation. I would like to be able to npm i preact-router and have the hook. It's been almost two years I'm using this in production with a specific build on my fork, this is really REALLY ReAlLy too long.

[JoviDeCroock]

@toniopelo I think this is published already

https://www.runpkg.com/?preact-router@4.0.1/dist/preact-router.module.js

[toniopelo]

@JoviDeCroock Wooow that's great. I figured that, without any response to my previous comments, it wasn't yet published. But I was wrong, thanks a lot for the good news 🎉 😄 .
I'll be able to change all my package.json and delete my fork, I'm a new guy 😛.