<p>
<img src="https://assets.solidjs.com/banner?project=Router&type=core" alt="Solid Router" />
</p>

# Solid Router [](https://www.npmjs.org/package/@solidjs/router)

A router lets you change your view based on the URL in the browser. This allows your "single-page" application to simulate a traditional multipage site. To use Solid Router, you specify components called Routes that depend on the value of the URL (the "path"), and the router handles the mechanism of swapping them in and out.

Solid Router is a universal router for SolidJS - it works whether you're rendering on the client or on the server. It was inspired by and combines paradigms of React Router and the Ember Router. Routes can be defined directly in your app's template using JSX, but you can also pass your route configuration directly as an object. It also supports nested routing, so navigation can change a part of a component, rather than completely replacing it.

It supports all of Solid's SSR methods and has Solid's transitions baked in, so use it freely with suspense, resources, and lazy components. Solid Router also allows you to define a load function that loads parallel to the routes ([render-as-you-fetch](https://epicreact.dev/render-as-you-fetch/)).

- [Getting Started](#getting-started)
- [Set Up the Router](#set-up-the-router)
- [Configure Your Routes](#configure-your-routes)
- [Create Links to Your Routes](#create-links-to-your-routes)
- [Dynamic Routes](#dynamic-routes)
- [Nested Routes](#nested-routes)
- [Hash Mode Router](#hash-mode-router)
- [Memory Mode Router](#memory-mode-router)
- [Data APIs](#data-apis)
- [Config Based Routing](#config-based-routing)
- [Components](#components)
- [Router Primitives](#router-primitives)
- [useParams](#useparams)
- [useNavigate](#usenavigate)
- [useLocation](#uselocation)
- [useSearchParams](#usesearchparams)
- [useIsRouting](#useisrouting)
- [useRouteData](#useroutedata)
- [useMatch](#usematch)
- [useBeforeLeave](#usebeforeleave)
- [SPAs in Deployed Environments](#spas-in-deployed-environments)

## Getting Started

### Set Up the Router

> npm i @solidjs/router

Install `@solidjs/router`, then start your application by rendering the router component

import { render } from "solid-js/web";
import { Router } from "@solidjs/router";

render(
  () => <Router />,
  document.getElementById("app")
);

This sets up a Router that will match on the url to display the desired page

### Configure Your Routes

Solid Router allows you to configure your routes using JSX:

1. Add each route to a `<Router>` using the `Route` component, specifying a path and an element or component to render when the user navigates to that path.

import { render } from "solid-js/web";
import { Router, Route } from "@solidjs/router";

import Home from "./pages/Home";
import Users from "./pages/Users";

render(() => (
  <Router>
    <Route path="/users" component={Users} />
    <Route path="/" component={Home} />
  </Router>
), document.getElementById("app"));

2. Provide a top level layout

This will always be there and won't update on page change. It is the ideal place to put top level navigation and Context Providers

import { render } from "solid-js/web";
import { Router, Route } from "@solidjs/router";

import Home from "./pages/Home";
import Users from "./pages/Users";

const App = props => (
  <>
    <h1>My Site with lots of pages</h1>
    {props.children}
  </>
)

render(() => (
  <Router>
    <Route component={App}>
      <Route path="/users" component={Users} />
      <Route path="/" component={Home} />
    </Route>
  </Router>
), document.getElementById("app"));

3. Lazy-load route components

This way, the `Users` and `Home` components will only be loaded if you're navigating to `/users` or `/`, respectively.

import { lazy } from "solid-js";
import { render } from "solid-js/web";
import { Router, Route } from "@solidjs/router";

const Users = lazy(() => import("./pages/Users"));
const Home = lazy(() => import("./pages/Home"));

const App = props => (
  <>
    <h1>My Site with lots of pages</h1>
    {props.children}
  </>
)

render(() => (
  <Router>
    <Route component={App}>
      <Route path="/users" component={Users} />
      <Route path="/" component={Home} />
    </Route>
  </Router>
), document.getElementById("app"));

### Create Links to Your Routes

Use an anchor tag that takes you to a route:

import { lazy } from "solid-js";
import { render } from "solid-js/web";
import { Router, Route } from "@solidjs/router";

const Users = lazy(() => import("./pages/Users"));
const Home = lazy(() => import("./pages/Home"));

const App = props => (
  <>
    <nav>
      <a href="/about">About</a>
      <a href="/">Home</a>
    </nav>
    <h1>My Site with lots of pages</h1>
    {props.children}
  </>
);

render(() => (
  <Router>
    <Route component={App}>
      <Route path="/users" component={Users} />
      <Route path="/" component={Home} />
    </Route>
  </Router>
), document.getElementById("app"));

## Dynamic Routes

If you don't know the path ahead of time, you might want to treat part of the path as a flexible parameter that is passed on to the component.

import { lazy } from "solid-js";
import { render } from "solid-js/web";
import { Router, Route } from "@solidjs/router";

const Users = lazy(() => import("./pages/Users"));
const User = lazy(() => import("./pages/User"));
const Home = lazy(() => import("./pages/Home"));

render(() => (
  <Router>
    <Route path="/users" component={Users} />
    <Route path="/users/:id" component={User} />
    <Route path="/" component={Home} />
  </Router>
 ), document.getElementById("app"));

The colon indicates that `id` can be any string, and as long as the URL fits that pattern, the `User` component will show.

You can then access that `id` from within a route component with `useParams`.

**Note on Animation/Transitions**:
Routes that share the same path match will be treated as the same route. If you want to force re-render you can wrap your component in a keyed `<Show>` like:

<Show when={params.something} keyed><MyComponent></Show>

---

Each path parameter can be validated using a `MatchFilter`.
This allows for more complex routing descriptions than just checking the presence of a parameter.

import { lazy } from "solid-js";
import { render } from "solid-js/web";
import { Router, Route } from "@solidjs/router";
import type { SegmentValidators } from "./types";

const User = lazy(() => import("./pages/User"));

const filters: MatchFilters = {
  parent: ["mom", "dad"], // allow enum values
  id: /^\d+$/, // only allow numbers
  withHtmlExtension: (v: string) => v.length > 5 && v.endsWith(".html"), // we want an `*.html` extension
};

render(() => (
  <Router>
    <Route
      path="/users/:parent/:id/:withHtmlExtension"
      component={User}
      matchFilters={filters}
    />
  </Router>
), document.getElementById("app"));

Here, we have added the `matchFilters` prop. This allows us to validate the `parent`, `id` and `withHtmlExtension` parameters against the filters defined in `filters`.
If the validation fails, the route will not match.

So in this example:

- `/users/mom/123/contact.html` would match,
- `/users/dad/123/about.html` would match,
- `/users/aunt/123/contact.html` would not match as `:parent` is not 'mom' or 'dad',
- `/users/mom/me/contact.html` would not match as `:id` is not a number,
- `/users/dad/123/contact` would not match as `:withHtmlExtension` is missing `.html`.

---

### Optional Parameters

Parameters can be specified as optional by adding a question mark to the end of the parameter name:

// Matches stories and stories/123 but not stories/123/comments
<Route path="/stories/:id?" component={Stories} />

### Wildcard Routes

`:param` lets you match an arbitrary name at that point in the path. You can use `*` to match any end of the path:

// Matches any path that begins with foo, including foo/, foo/a/, foo/a/b/c
<Route path="foo/*" component={Foo} />

If you want to expose the wild part of the path to the component as a parameter, you can name it:

<Route path="foo/*any" component={Foo} />

Note that the wildcard token must be the last part of the path; `foo/*any/bar` won't create any routes.

### Multiple Paths

Routes also support defining multiple paths using an array. This allows a route to remain mounted and not rerender when switching between two or more locations that it matches:

// Navigating from login to register does not cause the Login component to re-render
<Route path={["login", "register"]} component={Login} />

## Nested Routes

The following two route definitions have the same result:

<Route path="/users/:id" component={User} />

<Route path="/users">
  <Route path="/:id" component={User} />
</Route>

`/users/:id` renders the `<User/>` component, and `/users/` is an empty route.

Only leaf Route nodes (innermost `Route` components) are given a route. If you want to make the parent its own route, you have to specify it separately:

//This won't work the way you'd expect
<Route path="/users" component={Users}>
  <Route path="/:id" component={User} />
</Route>

// This works
<Route path="/users" component={Users} />
<Route path="/users/:id" component={User} />

// This also works
<Route path="/users">
  <Route path="/" component={Users} />
  <Route path="/:id" component={User} />
</Route>

You can also take advantage of nesting by using `props.children` passed to the route component.

function PageWrapper(props) {
  return (
    <div>
      <h1> We love our users! </h1>
      {props.children}
      <A href="/">Back Home</A>
    </div>
  );
}

<Route path="/users" component={PageWrapper}>
  <Route path="/" component={Users} />
  <Route path="/:id" component={User} />
</Route>;

The routes are still configured the same, but now the route elements will appear inside the parent element where the `props.children` was declared.

You can nest indefinitely - just remember that only leaf nodes will become their own routes. In this example, the only route created is `/layer1/layer2`, and it appears as three nested divs.

<Route
  path="/"
  component={(props) =>
    <div>
      Onion starts here {props.children}
    </div>
  }
>
  <Route
    path="layer1"
    component={(props) =>
      <div>
        Another layer {props.children}
      </div>
    }
  >
    <Route path="layer2"
      component={() => <div>Innermost layer</div>}>           </Route>
  </Route>
</Route>

## Data APIs

### `cache`

To prevent duplicate fetching and to trigger handle refetching we provide a cache api. That takes a function and returns the same function.

const getUser = cache((id) => {
  return (await fetch(`/api/users${id}`)).json()
}, "users") // used as cache key + serialized arguments

It is expected that the arguments to the cache function are serializable.

This cache accomplishes the following:

1. It does just deduping on the server for the lifetime of the request.
2. It does preload cache in the browser which lasts 10 seconds. When a route is preloaded on hover or when load is called when entering a route it will make sure to dedupe calls.
3. We have a reactive refetch mechanism based on key. So we can tell routes that aren't new to retrigger on action revalidation.
4. It will serve as a back/forward cache for browser navigation up to 5 mins. Any user based navigation or link click bypasses it. Revalidation or new fetch updates the cache.

This cache can be defined anywhere and then used inside your components with:

### `createAsync`

This is light wrapper over `createResource`. It is a simpler async primitive where the function tracks like `createMemo` and it expects a promise back that it turns into a Signal. Reading it before it ready causes Suspense/Transitions to trigger.

const user = createAsync(() => getUser(params.id))

`cache` API can be used with `createResource` but it must be passed into the tracking argument not the fetcher which means that you can't only pass a single argument as `createResource` defaults to just the fetcher. So to use a cache function with `createResource` you would need to:

const [user] = createResource(
  () => getUser(params.id),
  v => v // pass the return promise through
);

### `action`

Actions are data mutations that can trigger invalidations and further routing. A list of prebuilt response builders can be found below(TODO).

// anywhere
const myAction = action(async (data) => {
  await doMutation(data);
  return redirect("/", {
    invalidate: [getUser, data.id]  
  }) // returns a response
});

// in component
<form action={myAction} />

//or
<button type="submit" formaction={myAction}></button>

#### Notes of `<form>` implementation and SSR
This requires stable references as you can only serialize a string as an attribute, and across SSR they'd need to match. The solution is providing a unique name.

const myAction = action(async (args) => {}, "my-action");

### `useAction`

Instead of forms you can use actions directly by wrapping them in a `useAction` primitive. This is how we get the router context.

// in component
const submit = useAction(myAction)
submit(...args)

The outside of a form context you can use custom data instead of formData, and these helpers preserve types.

### `useSubmission`/`useSubmissions`

Are used to injecting the optimistic updates while actions are in flight. They either return a single Submission(latest) or all that match with an optional filter function.

type Submission<T, U> = {
  input: T;
  result: U;
  error: any;
  pending: boolean
  clear: () => {}
  retry: () => {}
}

const submissions = useSubmissions(action, (input) => filter(input));
const submission = useSubmission(action, (input) => filter(input));

### Load Functions

Even with the cache API it is possible that we have waterfalls both with view logic and with lazy loaded code. With load functions, we can instead start fetching the data parallel to loading the route, so we can use the data as soon as possible.

To do this, we can call our cache function in the load function.

import { lazy } from "solid-js";
import { Route } from "@solidjs/router";
import { getUser } from ... // the cache function

const User = lazy(() => import("./pages/users/[id].js"));

// load function
function loadUser({params, location}) {
  void getUser(params.id)
}

// Pass it in the route definition
<Route path="/users/:id" component={User} load={loadUser} />;

The load function is called when the Route is loaded or eagerly when links are hovered. Inside your page component you

// pages/users/[id].js
import { getUser } from ... // the cache function
    
export default function User(props) {
  const user = createAsync(() => getUser(props.params.id));
  return <h1>{user().name}</h1>;
}

As its only argument, the load function is passed an object that you can use to access route information:

| key | type | description |
| -------- | ------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------- |
| params | object | The route parameters (same value as calling `useParams()` inside the route component) |
| location | `{ pathname, search, hash, query, state, key}` | An object that you can use to get more information about the path (corresponds to [`useLocation()`](#uselocation)) |

A common pattern is to export the preload function and data wrappers that corresponds to a route in a dedicated `route.data.js` file. This way, the data function can be imported without loading anything else.

import { lazy } from "solid-js";
import { Route } from "@solidjs/router";
import loadUser from "./pages/users/[id].data.js";
const User = lazy(() => import("/pages/users/[id].js"));

// In the Route definition
<Route path="/users/:id" component={User} load={loadUser} />;

## Config Based Routing

You don't have to use JSX to set up your routes; you can pass an object:

import { lazy } from "solid-js";
import { render } from "solid-js/web";
import { Router } from "@solidjs/router";

const routes = [
  {
    path: "/users",
    component: lazy(() => import("/pages/users.js")),
  },
  {
    path: "/users/:id",
    component: lazy(() => import("/pages/users/[id].js")),
    children: [
      {
        path: "/",
        component: lazy(() => import("/pages/users/[id]/index.js")),
      },
      {
        path: "/settings",
        component: lazy(() => import("/pages/users/[id]/settings.js")),
      },
      {
        path: "/*all",
        component: lazy(() => import("/pages/users/[id]/[...all].js")),
      },
    ],
  },
  {
    path: "/",
    component: lazy(() => import("/pages/index.js")),
  },
  {
    path: "/*all",
    component: lazy(() => import("/pages/[...all].js")),
  },
];

render(() =>
  <Router>{routes}</Router>,
  document.getElementById("app")
);

## Alternative Routers

### Hash Mode Router

By default, Solid Router uses `location.pathname` as route path. You can simply switch to hash mode through the `source` property on `<Router>` component.

import { Router, hashIntegration } from "@solidjs/router";

<Router source={hashIntegration()} />;

### Memory Mode Router

You can also use memory mode router for testing purpose.

import { Router, memoryIntegration } from "@solidjs/router";

<Router source={memoryIntegration()} />;

## Components

### `<A>`

Like the `<a>` tag but supports relative paths and active class styling.

The `<A>` tag has an `active` class if its href matches the current location, and `inactive` otherwise. **Note:** By default matching includes locations that are descendents (eg. href `/users` matches locations `/users` and `/users/123`), use the boolean `end` prop to prevent matching these. This is particularly useful for links to the root route `/` which would match everything.

| prop | type | description |
| ------------- | ------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| href | string | The path of the route to navigate to. This will be resolved relative to the route that the link is in, but you can preface it with `/` to refer back to the root. |
| noScroll | boolean | If true, turn off the default behavior of scrolling to the top of the new page |
| replace | boolean | If true, don't add a new entry to the browser history. (By default, the new page will be added to the browser history, so pressing the back button will take you to the previous route.) |
| state | unknown | [Push this value](https://developer.mozilla.org/en-US/docs/Web/API/History/pushState) to the history stack when navigating |
| inactiveClass | string | The class to show when the link is inactive (when the current location doesn't match the link) |
| activeClass | string | The class to show when the link is active |
| end | boolean | If `true`, only considers the link to be active when the curent location matches the `href` exactly; if `false`, check if the current location _starts with_ `href` |

### `<Navigate />`

Solid Router provides a `Navigate` component that works similarly to `A`, but it will _immediately_ navigate to the provided path as soon as the component is rendered. It also uses the `href` prop, but you have the additional option of passing a function to `href` that returns a path to navigate to:

function getPath({ navigate, location }) {
  // navigate is the result of calling useNavigate(); location is the result of calling useLocation().
  // You can use those to dynamically determine a path to navigate to
  return "/some-path";
}

// Navigating to /redirect will redirect you to the result of getPath
<Route path="/redirect" component={() => <Navigate href={getPath} />} />;

### `<Route>`

The Component for defining Routes:

| prop | type | description |
|-|-|-|
|TODO

## Router Primitives

Solid Router provides a number of primitives that read off the Router and Route context.

### useParams

Retrieves a reactive, store-like object containing the current route path parameters as defined in the Route.

const params = useParams();

// fetch user based on the id path parameter
const [user] = createResource(() => params.id, fetchUser);

### useNavigate

Retrieves method to do navigation. The method accepts a path to navigate to and an optional object with the following options:

- resolve (_boolean_, default `true`): resolve the path against the current route
- replace (_boolean_, default `false`): replace the history entry
- scroll (_boolean_, default `true`): scroll to top after navigation
- state (_any_, default `undefined`): pass custom state to `location.state`

**Note:** The state is serialized using the [structured clone algorithm](https://developer.mozilla.org/en-US/docs/Web/API/Web_Workers_API/Structured_clone_algorithm) which does not support all object types.

const navigate = useNavigate();

if (unauthorized) {
  navigate("/login", { replace: true });
}

### useLocation

Retrieves reactive `location` object useful for getting things like `pathname`

const location = useLocation();

const pathname = createMemo(() => parsePath(location.pathname));

### useSearchParams

Retrieves a tuple containing a reactive object to read the current location's query parameters and a method to update them. The object is a proxy so you must access properties to subscribe to reactive updates. Note values will be strings and property names will retain their casing.

The setter method accepts an object whose entries will be merged into the current query string. Values `''`, `undefined` and `null` will remove the key from the resulting query string. Updates will behave just like a navigation and the setter accepts the same optional second parameter as `navigate` and auto-scrolling is disabled by default.

const [searchParams, setSearchParams] = useSearchParams();

return (
  <div>
    <span>Page: {searchParams.page}</span>
    <button
      onClick={() =>
        setSearchParams({ page: (parseInt(searchParams.page) || 0) + 1 })
      }
    >
      Next Page
    </button>
  </div>
);

### useIsRouting

Retrieves signal that indicates whether the route is currently in a Transition. Useful for showing stale/pending state when the route resolution is Suspended during concurrent rendering.

const isRouting = useIsRouting();

return (
  <div classList={{ "grey-out": isRouting() }}>
    <MyAwesomeConent />
  </div>
);

### useMatch

`useMatch` takes an accessor that returns the path and creates a Memo that returns match information if the current path matches the provided path. Useful for determining if a given path matches the current route.

const match = useMatch(() => props.href);

return <div classList={{ active: Boolean(match()) }} />;

### useBeforeLeave

`useBeforeLeave` takes a function that will be called prior to leaving a route. The function will be called with:

- from (_Location_): current location (before change).
- to (_string | number_}: path passed to `navigate`.
- options (_NavigateOptions_}: options passed to `navigate`.
- preventDefault (_void function_): call to block the route change.
- defaultPrevented (_readonly boolean_): true if any previously called leave handlers called preventDefault().
- retry (_void function_, _force?: boolean_ ): call to retry the same navigation, perhaps after confirming with the user. Pass `true` to skip running the leave handlers again (ie force navigate without confirming).

Example usage:

useBeforeLeave((e: BeforeLeaveEventArgs) => {
  if (form.isDirty && !e.defaultPrevented) {
    // preventDefault to block immediately and prompt user async
    e.preventDefault();
    setTimeout(() => {
      if (window.confirm("Discard unsaved changes - are you sure?")) {
        // user wants to proceed anyway so retry with force=true
        e.retry(true);
      }
    }, 100);
  }
});

## Migrations from 0.8.x

v0.9.0 brings some big changes to support the future of routing including Islands/Partial Hydration hybrid solutions. Most notably there is no Context API available in non-hydrating parts of the application.

The biggest changes are around removed APIs that need to be replaced.

### `<Outlet>`, `<Routes>`, `useRoutes`

This is no longer used and instead will use `props.children` passed from into the page components for outlets. Nested Routes inherently cause waterfalls and are Outlets in a sense themselves. We do not want to encourage the pattern and if you must do it you can always nest `<Routers>` with appropriate base path.

## `element` prop removed from `Route`

Related without Outlet component it has to be passed in manually. At which point the `element` prop has less value. Removing the second way to define route components to reduce confusion and edge cases.

### `data` functions & `useRouteData`

These have been replaced by a load mechanism. This allows link hover preloads (as the load function can be run as much as wanted without worry about reactivity). It support deduping/cache APIs which give more control over how things are cached. It also addresses TS issues with getting the right types in the Component without `typeof` checks.

## SPAs in Deployed Environments

When deploying applications that use a client side router that does not rely on Server Side Rendering you need to handle redirects to your index page so that loading from other URLs does not cause your CDN or Hosting to return not found for pages that aren't actually there.

Each provider has a different way of doing this. For example on Netlify you create a `_redirects` file that contains:

/*   /index.html   200

On Vercel you add a rewrites section to your `vercel.json`:

{
  "rewrites": [
    {
      "source": "/(.*)",
      "destination": "/index.html"
    }
  ]
}