Nano Stores Router

A tiny URL router for Nano Stores state manager.

Small. 838 bytes (minified and gzipped). Zero dependencies. It uses Size Limit to control size.
It has good TypeScript support.
Framework agnostic. Can be used for React, Preact, Vue, Svelte, and vanilla JS.

Since Nano Stores promote moving logic to store, the router is a store, not a component in UI framework like React.

// stores/router.ts
import { createRouter } from '@nanostores/router'

export const router = createRouter({
  home: '/',
  category: '/posts/:categoryId',
  post: '/posts/:categoryId/:postId'
}

Store in active mode listen for <a> clicks on document.body and Back button in browser.

// components/layout.tsx
import { useStore } from '@nanostores/react'

import { router } from '../stores/router.js'

export const Layout = () => {
  const page = useStore(router)

  if (!page) {
    return <Error404 />
  } else if (page.route === 'home') {
    return <HomePage />
  } else if (page.route === 'category') {
    return <CategoryPage categoryId={page.params.categoryId} />
  } else if (page.route === 'post') {
    return <PostPage postId={page.params.postId} />
  }
}

Install

npm install nanostores @nanostores/router

Usage

See Nano Stores docs about using the store and subscribing to store’s changes in UI frameworks.

Routes

Routes is an object of route’s name to route pattern:

createRouter({
  route1: '/',
  route2: '/path/:var1/and/:var2',
  route3: [/\/posts\/(draft|new)\/(\d+)/, (type, id) => ({ type, id })]
})

For string patterns you can use :name for variable parts. To make the parameter optional, mark it with the ? modifier:

createRouter({
  routeName: '/profile/:id?/:tab?'
})

Routes can have RegExp patterns. They should be an array with function, which convert () groups to key-value map.

For TypeScript, router parameters will be converted to types automatically. You need to use TypeScript ≥5.x.

createRouter({
  routeName: '/path/:var1/and/:var2',
  routeName2: [/path2/, () => ({ num: 1, str: '' })]
})

/**
 * Params will be inferred as:
 * {
 *   routeName: { var1: string, var2: string },
 *   routeName2: { num: number, str: string }
 * }
 */

Search query routing

To use search query like ?a=1&b=2 in routes you need to set search option:

createRouter({
  home: '/p/?page=home'
}, {
  search: true
})

Router will works with ?search part as a string. Parameters order will be critical.

There is another store to watch for ?search parameters separately. It can be useful where ?search is used only as sub-routes for specific page. For instance, for filters settings on search page.

// stores/searchParams.ts
import { createSearchParams } from '@nanostores/router'

export const searchParams = createSearchParams()

// stores/searchResult.ts
import { searchParams } from '../searchParams'

export const searchResult = atom([])

onMount(searchResult, () => {
  return searchParams.subscribe(params => {
    searchResult.set(await search(params))
  })
})

function changeSearchParam(key: 'sort' | 'filter', value: string) {
  searchParams.set({ ...searchParams.get(), [key]: value })
}

Clicks Tracking

By default, router and ?search params store will add click event listener on window to track links clicks.

You can disable this behavior by links: false options and create custom <Link> component.

export const router = createRouter({ … }, { links: false })

function onClick (e) {
  let link = event.target.closest('a')
  if (isPjax(link, e)) {
    router.open(new Url(link.href).pathname)
  }
}

export const Link = (props) => {
  return <a onClick={onClick} {...props}></a>
}

URL Generation

Using getPagePath() avoids hard coding URL in templates. It is better to use the router as a single place of truth.

import { getPagePath } from '@nanostores/router'

…
  <a href={getPagePath(router, 'post', { categoryId: 'guides', id: '10' })}>

If you need to change URL programmatically you can use openPage or redirectPage:

import { openPage, redirectPage } from '@nanostores/router'

function requireLogin () {
  openPage(router, 'login')
}

function onLoginSuccess() {
  // Replace login route, so we don’t face it on back navigation
  redirectPage(router, 'home')
}

Server-Side Rendering

Router can be used in Node environment without window and location. In this case, it will always return route to / path.

You can manually set any other route:

if (isServer) {
  router.open('/posts/demo/1')
}

vostrik/router