A fresh high-level react router designed for flexible route transitions

Because managing route transitions with React is always complicated, this router is designed to allow flexible transitions. It provides Stack component who render previous and current page component when route change.

This router loads history , path-to-regexp and @cher-ami/debug as dependencies.

• example client
• example ssr
• example history block

• Installation
• Simple usage
• Dynamic routes
• Sub Router
• Manage Transitions
  • Default sequential transitions
  • Custom transitions
• SSR support
• Workflow
• thanks
• credits

API

Components:

• <Router /> Wrap Link and stack component
• <Link /> Trig current stack
• <Stack /> Wrap previous and current page

Hooks:

• useRouter Get current router informations like currentRoute and previousRoute
• useLocation Get current location and set new location
• useStack Allow to the parent Stack to handle page transitions and refs
• useRouteCounter Get global history route counter
• useHistory Execute callback each time history changes
• useLang get and set langService current language object changes

Services:

• LangService Manage :lang params
• Translate Path

Global:

• Helpers Global Routers helpers
• Routers object Global Routers object contains all routers properties (history, instances...)

$ npm i @cher-ami/router -s

import React from "react"
import { Router, Link, Stack } from "@cher-ami/router"
import { createBrowserHistory } from "history"

const routesList = [
  {
    path: "/",
    component: HomePage,
  },
  {
    path: "/foo",
    component: FooPage,
  },
]

const history = createBrowserHistory()

function App() {
  return (
    <Router routes={routesList} history={history} base={"/"}>
      <nav>
        <Link to={"/"} />
        <Link to={"/foo"} />
      </nav>
      <Stack />
    </Router>
  )
}

Page component need to be wrapped by React.forwardRef. The handleRef lets hold transitions, and ref used by <Stack /> component.

import React from "react"
import { useStack } from "@cher-ami/router"

const FooPage = forwardRef((props, handleRef) => {
  const componentName = "FooPage"
  const rootRef = useRef(null)

  // create custom page transitions (example-client with GSAP)
  const playIn = () => {
    return new Promise((resolve) => {
      gsap.from(rootRef.current, { autoAlpha: 0, onComplete: resolve })
    })
  }
  const playOut = () => {
    return new Promise((resolve) => {
      gsap.to(rootRef.current, { autoAlpha: 0, onComplete: resolve })
    })
  }

  // register page transition properties used by Stack component
  useStack({ componentName, handleRef, rootRef, playIn, playOut })

  return (
    <div className={componentName} ref={rootRef}>
      {componentName}
    </div>
  )
})

cher-ami router use path-to-regexp which accept path parameters. (check this documentation). For example, URL /blog/my-article will match with this route object:

const routesList = [
  {
    path: "/blog/:id",
    component: ArticlePage,
  },
]

You can access route parameters by page component props or by useRouter() hook.

import React, { useEffect, forwardRef } from "react"
import { useRoute } from "@cher-ami/router"

const ArticlePage = forwardRef((props, handleRef) => {
  useEffect(() => {
    console.log(props.params) // { id: "my-article" }
  }, [props])

  // or from any nested components
  const { currentRoute } = useRouter()
  useEffect(() => {
    console.log(currentRoute.props.params) // { id: "my-article" }
  }, [currentRoute])

  // ...
})

Also, it is possible to match a specific route by a simple dynamic route parameter for the "not found route" case. In this case, the routes object order declaration is important. /:rest path route need to be the last of the routesList array.

const routesList = [
  {
    path: "/",
    component: HomePage,
  },
  {
    path: "/foo",
    component: FooPage,
  },
  // if "/" and "/foo" doesn't match with the current URL, this route will be rendered
  {
    path: "/:rest",
    component: NotFoundPage,
  },
]

cher-ami router supports nested routes from sub routers instance 🙏🏽. It is possible to nest as many routers as you want.

1. Define children routes in initial routes list with children property;

const routesList = [
  {
    path: "/",
    component: HomePage,
  },
  {
    path: "/foo",
    component: FooPage,

    // define children routes here
    children: [
      {
        path: "/people",
        component: PeoplePage,
      },
      {
        path: "/yolo",
        component: YoloPage,
      },
    ],
  },
]

2. Children were defined within the route that render FooPage component, so you can then create a new router instance in this component.

3. The new subRouter needs his own base and routes list, getSubRouterBase and getSubRouterRoutes functions are available to get them.

import React from "react"
import {
  Router,
  useStack,
  Stack,
  useRouter,
  getPathByRouteName,
  getSubRouterBase,
  getSubRouterRoutes,
} from "@cher-ami/router"

const FooPage = forwardRef((props, handleRef) => {
  const router = useRouter()
  // Parsed routes list and get path by route name -> "/foo"
  const path = getPathByRouteName(router.routes, "FooPage")
  // (if last param is false, '/:lang' will be not added) -> "/base/:lang/foo"
  const subBase = getSubRouterBase(path, router.base, true)
  // get subRoutes
  const subRoutes = getSubRouterRoutes(path, router.routes)
  return (
    <div>
      <Router base={subBase} routes={subRoutes}>
        <Stack />
      </Router>
    </div>
  )
})

ManageTransitions function allows to define, "when" and "in what conditions", routes transitions will be exectued.

By default, a "sequential" transitions senario is used by Stack component: the previous page play out performs, then the new page play in.

const sequencialTransition = ({ previousPage, currentPage, unmountPreviousPage }) => {
  return new Promise(async (resolve) => {
    const $current = currentPage?.$element

    // hide new page
    if ($current) $current.style.visibility = "hidden"

    // play out and unmount previous page
    if (previousPage) {
      await previousPage.playOut()
      unmountPreviousPage()
    }

    // wait page isReady promise
    await currentPage?.isReadyPromise?.()

    // show and play in new page
    if (currentPage) {
      if ($current) $current.style.visibility = "visible"
      await currentPage?.playIn()
    }

    resolve()
  })
}

It's however possible to create a custom transitions senario function and pass it to the Stack manageTransitions props. In this example, we would like to create a "crossed" route senario: the previous page playOut performs at the same time than the new page playIn.

const App = (props, handleRef) => {
  const customSenario = ({ previousPage, currentPage, unmountPreviousPage }) => {
    return new Promise(async (resolve) => {
      // write a custom "crossed" senario...
      if (previousPage) previousPage?.playOut()
      if (currentPage) await currentPage?.playIn()

      resolve()
    })
  }

  return (
    // ...
    <Stack manageTransitions={customSenario} />
  )
}

This router is compatible with SSR due to using staticLocation props instead of history props on Router instance. In this case, the router will match only with staticLocation props value and render the appropiate route without invoking the browser history. (Because window is not available on the server).

<Router
  routes={routesList}
  staticLocation={"/foo"}
  // history={createBrowserHistory()}
>
  // ...
</Router>

In order to use this router on server side, we need to be able to request API on the server side too. In this case, request will be print as javascript window object on the renderToString html server response. The client will got this response.

To be able to request on server side (and on client side too), getStaticProps route property is available:

   {
    path: "/article/:slug",
    component: ArticlePage,
    name: "Article",
    getStaticProps: async (props, currentLang) => {
      // props contains route props and params (ex: slug: "article-1")
      const res = await fetch(`https://api.com/posts/${currentLang.key}/${props.params.slug}`);
      const api = await res.json();
      return { api };
    }
  }

Then, get the response data populated in page component props:

function HomePage({ api }) {
  return <div>{api.title}</div>
}

For larger example, check the example-ssr folder.

# Install dependencies
pnpm i

## build watch
pnpm run build:watch

## start tests
pnpm run test:watch

## start all examples
pnpm run dev

## Before publishing
pnpm run pre-publish

## Increment version
npm version {patch|minor|major}

## Publish
npm publish

Router component creates a new router instance.

<Router routes={} base={} history={} staticLocation={} middlewares={} id={}>
  {/* can now use <Link /> and <Stack /> component */}
</Router>

Props:

• routes TRoute[] Routes list
• base string Base URL - default: "/"
• history BrowserHistory | HashHistory | MemoryHistory (optional) create and set an history - default : BrowserHistory History mode can be BROWSER , HASH , MEMORY . For more information, check the history library documentation \
• isHashHistory boolean (optional) default false. If you use HashHistory, you must set isHashHistory to true. ⚠️ Add it to sub-router too
• staticLocation string (optional) use static URL location matching instead of history
• middlewares [] (optional) add routes middleware function to patch each routes)
• id ?number | string (optional) id of the router instance - default : 1

Trig new route.

<Link to={} className={} />

Props:

• to string | TOpenRouteParams Path ex: /foo or {name: "FooPage" params: { id: bar }}. "to" props accepts same params than setLocation.
• children ReactNode children link DOM element
• onClick ()=> void (optional) execute callback on the click event
• className string (optional) Class name added to component root DOM element

Render previous and current page component.

<Stack manageTransitions={} className={} />

Props:

• manageTransitions (T:TManageTransitions) => Promise<void> (optional) This function allows to create the transition scenario. If no props is filled, a sequential transition will be executed.
• className string (optional) className added to component root DOM element

type TManageTransitions = {
  previousPage: IRouteStack
  currentPage: IRouteStack
  unmountPreviousPage: () => void
}

interface IRouteStack {
  componentName: string
  playIn: () => Promise<any>
  playOut: () => Promise<any>
  isReady: boolean
  $element: HTMLElement
  isReadyPromise: () => Promise<void>
}

Get current router informations:

const router = useRouter()

Returns:

useRouter() returns an object with these public properties:

• currentRoute TRoute Current route object
• previousRoute TRoute Previous route object
• routeIndex number Current router index
• base string Formated base URL
• setPaused (paused:boolean) => void Paused router instance
• getPaused () => void Get paused state of router instance

// previousRoute and currentRoute
type TRoute = Partial<{
  path: string | { [x: string]: string }
  component: React.ComponentType<any>
  base: string
  name: string
  parser: Match
  props: TRouteProps
  children: TRoute[]
  url: string
  params?: TParams
  queryParams?: TQueryParams
  hash?: string
  getStaticProps: (props: TRouteProps, currentLang: TLanguage) => Promise<any>
  _fullUrl: string // full URL who not depends on current instance
  _fullPath: string // full Path /base/:lang/foo/second-foo
  _langPath: { [x: string]: string } | null
  _context: TRoute
}>

Allow the router to change location.

const [location, setLocation] = useLocation()
// give URL
setLocation("/bar")
// or an object
setLocation({ name: "FooPage", params: { id: "2" } })

Returns:

An array with these properties:

• location string Get current pathname location
• setLocation (path:string | TOpenRouteParams) => void Open new route

type TOpenRouteParams = {
  name: string
  params?: TParams
  queryParams?: TQueryParams
  hash?: string
}

useStack allows to the parent Stack to handle page transitions and refs.

usage:

import React from "react";
import { useStack } from "@cher-ami/router";

const FooPage = forwardRef((props, handleRef) => {
  const componentName = "FooPage";
  const rootRef = useRef(null);

  const playIn = () => new Promise((resolve) => {  ... });
  const playOut = () => new Promise((resolve) => {  ... });

  // "handleRef" will get properties via useImperativeHandle
  useStack({
    componentName,
    handleRef,
    rootRef,
    playIn,
    playOut
  });

  return (
    <div className={componentName} ref={rootRef}>
      {/* ... */}
    </div>
  );
});

useStack hook can also receive isReady state from the page component. This state allows for example to wait for fetching data before page playIn function is executed.

// ...

const [pageIsReady, setPageIsReady] = useState(false)

useEffect(() => {
  // simulate data fetching or whatever for 2 seconds
  setTimeout(() => {
    setPageIsReady(true)
  }, 2000)
}, [])

useStack({
  componentName,
  handleRef,
  rootRef,
  playIn,
  playOut,
  // add the state to useStack
  // playIn function wait for isReady to change to true
  isReady: pageIsReady,
})

// ...

How does it work? useStack hook registers isReady state and isReadyPromise in handleRef. manageTransitions can now use isReadyPromise in its own thread senario.

const customManageTransitions = ({ previousPage, currentPage, unmountPreviousPage }) => {
  return new Promise(async (resolve) => {
    // ...
    // waiting for page "isReady" state to change to continue...
    await currentPage?.isReadyPromise?.()
    // ...
    resolve()
  })
}

Demo codesandbox: wait-is-ready

Parameters:

• componentName string Name of current component
• handleRef MutableRefObject<any> Ref handled by parent component
• rootRef MutableRefObject<any> Ref on root component element
• playIn () => Promise<any> (optional) Play in transition - default: new Promise.resolve()
• playOut () => Promise<any> (optional) Play out transition - default: new Promise.resolve()
• isReady boolean (optional) Is ready state - default: true

Returns:

nothing

Returns route counter

const { routeCounter, isFirstRoute, resetCounter } = useRouteCounter()

Parameters:

nothing

Returns:

An object with these properties:

• routerCounter number Current route number - default: 1
• isFirstRoute boolean Check if it's first route - default: true
• resetCounter () => void Reset routerCounter & isFirstRoute states

Allow to get the global router history and execute a callback each time history change.

const history = useHistory((e) => {
  // do something
})

Parameters:

• callback (event) => void Callback function to execute each time the history change

Returns:

• history History : global history object. (Routers.history)

Get and update langService current language object.

const [lang, setLang] = useLang()
useEffect(() => {
  // when current lang change
  // it's usefull only if setLang method do not refresh the page.
}, [lang])

// set new lang with lang object "key" property value only
setLang("en")
// set new lang with the lang object
setLang({ key: "en" })

Returns:

Array of :

• lang TLanguage : current lang object
• setLang (lang: TLanguage | string, force: boolean) => void : set new lang object (same API than langService.setLang)

Manage :lang params from anywhere inside Router scope. Add isHashHistory to true if you are using createHashHistory() for the router.

import { LangService } from "@cher-ami/router"
import { Stack } from "./Stack"

const base = "/"

// first lang object is default lang
const languages = [{ key: "en" }, { key: "fr" }, { key: "de" }]
// optionally, default lang can be defined explicitly
// const languages = [{ key: "en" }, { key: "fr", default: true }, { key: "de" }];

// Create LangService instance
const langService = new LangService({
  languages,
  showDefaultLangInUrl: true,
  base,
  //isHashHistory: true // Optional, only if history is hashHistory
})

;<Router
  langService={langService}
  routes={routesList}
  base={base}
  //isHashHistory={true} // Optional, only if history is hashHistory
>
  <App />
</Router>

Inside the App

function App() {
  // get langService instance from router context
  const { langService } = useRouter()

  return (
    <div>
      <button onClick={() => langService.setLang({ key: "de" })}>
        switch to "de" lang
      </button>
      <nav>
        {/* will return /de */}
        <Link to={"/"} />
        {/* will return /de/foo */}
        <Link to={"/foo"} />
      </nav>
      <Stack />
    </div>
  )
}

Methods:

Initialize LangService by passing it to "langService" Router props

constructor object properties:

• languages: list on language objects
• showDefaultLangInUrl: choose if default language is visible in URL or not
• base: set the same than router base
• isHashHistory: set to true if hashHistory is used (optional, default false)

const langService = new LangService({
  languages: [{ key: "en" }, { key: "fr" }],
  showDefaultLangInUrl: true,
  base: "/",
})

langService instance is available in Router scope from useRouter() hook.

const Page = () => {
  const { langService } = useRouter()
  // langService.setLang() ...
}

Return languages list

const langages = langService.languages

Return current Language object.

const lang = langService.currentLang
// { key: "..." }

Return default language object

const defaultLang = langService.defaultLang
// { key: "..." }

Return langService init state

const isInit = langService.isInit

Return isHashHistory state.

const isHashHistory = langService.isHashHistory
// true | false

Switch to another available language. This method can be called in nested router component only.

• forcePageReload: choose if we reload the full application or using the internal router stack to change the language

langService.setLang({ key: "de" })

If URL is /, showDefaultLangInUrl is set to true and default lang is 'en', it will redirect to /en.

• forcePageReload: choose if we reload the full application or using the internal router stack to change the language

langService.redirectToDefaultLang()

Same than redirectToDefaultLang method but redirect to the user navigator.language. If the browser language doesn't exist in Languages array, we redirect to the default lang.

langService.redirectToBrowserLang()

Paths can be translated by lang in route path property. This option works only if LangService instance is created and passed to the Router component.

  {
    path: { en: "/foo", fr: "/foo-fr", de: "/foo-de" },
    component: FooPage,
  }

(args: string | TOpenRouteParams, base?:string, allRoutes?: TRoute[]) => string

Create a formated URL by string, or TOpenRouteParams

(args: string | TOpenRouteParams, history?) => void

Push new route in current history. Stack(s) component(s) will return the appriopriate route.

Routers is a global object who contains all routers informations. Because @cher-ami/router is possibly multi-stack, we need a global object to store shared informations between router instances.

TRoute[]

Final routes array used by the router be

HashHistory | MemoryHistory | BrowserHistory

Selected history mode. all history API is avaible from this one.

boolean

Return the value set on the Router component

LangService

LangService instance given to the first Router component.

number

How many route are resolved from the start of the session. This property is also available from useRouteCounter.

boolean

Is it the first route of the session. This property is also available from useRouteCounter.

cher-ami router API is inspired by wouter, solidify router and vue router API.

Willy Brauner & cher-ami