This PR introduces [Edge Runtime](https://edge-runtime.vercel.app/) for emulating [Edge Functions](https://vercel.com/features/edge-functions) locally.
Every time you run a [middleware](https://nextjs.org/docs/advanced-features/middleware) locally via `next dev`, an isolated edge runtime context will be created.
These contexts have the same constraints as production servers, plus they don't pollute the global scope; Instead, all the code run in a vm on top of a Node.js process.
Additionally, `@edge-runtime/jest-environment` has been added to make easier testing Edge Functions in a programmatic way.
It dropped the following polyfills from Next.js codebase, since they are now part of Edge Runtime:
- abort-controller
- formdata
- uuid
- web-crypto
- web-streams
Co-authored-by: Gal Schlezinger <2054772+Schniz@users.noreply.github.com>
* Do not exclude internal _next request in middleware
* Allow for `NextURL` to parse prefetch requests
* Add test for middleware data prefetch
* Refactor `hasBasePath` and `replaceBasePath`
* Refactor `removeTrailingSlash`
* Refactor parsed next url to use `getNextPathnameInfo`
* Allow to configure `NextURL`
* Ensure middleware rewrites with always with a locale
Co-authored-by: JJ Kasper <jj@jjsweb.site>
_Hello Next.js team! First PR here, I hope I've followed the right practices._
### What's in there?
It has been decided to only support the following uses cases in Next.js' middleware:
- rewrite the URL (`x-middleware-rewrite` response header)
- redirect to another URL (`Location` response header)
- pass on to the next piece in the request pipeline (`x-middleware-next` response header)
1. during development, a warning on console tells developers when they are returning a response (either with `Response` or `NextResponse`).
2. at build time, this warning becomes an error.
3. at run time, returning a response body will trigger a 500 HTTP error with a JSON payload containing the detailed error.
All returned/thrown errors contain a link to the documentation.
This is a breaking feature compared to the _beta_ middleware implementation, and also removes `NextResponse.json()` which makes no sense any more.
### How to try it?
- runtime behavior: `HEADLESS=true yarn jest test/integration/middleware/core`
- build behavior : `yarn jest test/integration/middleware/build-errors`
- development behavior: `HEADLESS=true yarn jest test/development/middleware-warnings`
### Notes to reviewers
The limitation happens in next's web adapter. ~The initial implementation was to check `response.body` existence, but it turns out [`Response.redirect()`](https://github.com/vercel/next.js/blob/canary/packages/next/server/web/spec-compliant/response.ts#L42-L53) may set the response body (https://github.com/vercel/next.js/pull/31886). Hence why the proposed implementation specifically looks at response headers.~
`Response.redirect()` and `NextResponse.redirect()` do not need to include the final location in their body: it is handled by next server https://github.com/vercel/next.js/blob/canary/packages/next/server/next-server.ts#L1142
Because this is a breaking change, I had to adjust several tests cases, previously returning JSON/stream/text bodies. When relevant, these middlewares are returning data using response headers.
About DevEx: relying on AST analysis to detect forbidden use cases is not as good as running the code.
Such cases are easy to detect:
```js
new Response('a text value')
new Response(JSON.stringify({ /* whatever */ })
```
But these are false-positive cases:
```js
function returnNull() { return null }
new Response(returnNull())
function doesNothing() {}
new Response(doesNothing())
```
However, I see no good reasons to let users ship middleware such as the one above, hence why the build will fail, even if _technically speaking_, they are not setting the response body.
## Feature
- [x] Implements an existing feature request or RFC. Make sure the feature request has been accepted for implementation before opening a PR.
- [ ] Related issues linked using `fixes #number`
- [x] Integration tests added
- [x] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [x] Errors have helpful link attached, see `contributing.md`
## Documentation / Examples
- [x] Make sure the linting passes by running `yarn lint`
Hello,
This is an iteration after first work at https://github.com/vercel/next.js/pull/36478.
What that PR missed is a way to just get a cookie value. Well, this PR adds two new things:
`cookies.get` returns the cookie value that could be `string | undefined`:
```js
const response = new NextResponse()
response.cookies.set('foo', 'bar', { path: '/test' })
const value = response.cookies.get('foo')
console.log(value) // => 'bar'
```
Additionally, if you want to know all the cookie details, you can use `cookies.getWithOptions`:
```js
const response = new NextResponse()
response.cookies.set('foo', 'bar', { path: '/test' })
const { value, options } response.cookies.getWithOptions('foo')
console.log(value) // => 'bar'
console.log(options) // => { Path: '/test' }
```
This PR introduces a more predictable API to manipulate cookies in an Edge Function context.
```js
const response = new NextResponse()
// set a cookie
response.cookies.set('foo, 'bar') // => set-cookie: 'foo=bar; Path=/'`
// set another cookie
response.cookies.set('fooz, 'barz') // => set-cookie: 'foo=bar; Path=/, fooz=barz; Path=/'`
// delete a cookie means mark it as expired
response.cookies.delete('foo') // => set-cookie: 'foo=; Path=/; Expires=Thu, 01 Jan 1970 00:00:00 GMT, fooz=barz; Path=/'`
// clear all cookies means mark all of them as expired
response.cookies.clear() // => set-cookie: 'fooz=; Path=/; Expires=Thu, 01 Jan 1970 00:00:00 GMT, foo=; Path=/; Expires=Thu, 01 Jan 1970 00:00:00 GMT'`
```
This new cookies API uses [Map](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map) interface, and it's available for `NextRequest` and `NextResponse`.
Additionally, you can pass a specific cookies option as a third argument in `set` method:
```js
response.cookies.set('foo', 'bar', {
path: '/',
maxAge: 60 * 60 * 24 * 7,
httpOnly: true,
sameSite: 'strict',
domain: 'example.com'
}
```
**Note**: `maxAge` it's in seconds rather than milliseconds.
Any cookie manipulation will be reflected over the `set-cookie` header, transparently.
closes#31719
fixes https://github.com/vercel/next.js/issues/36136
## Bug
- [X] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have helpful link attached, see `contributing.md`
## Feature
- [ ] Implements an existing feature request or RFC. Make sure the feature request has been accepted for implementation before opening a PR.
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [ ] Errors have helpful link attached, see `contributing.md`
## Documentation / Examples
- [ ] Make sure the linting passes by running `yarn lint`
Something I noticed while using Middleware is that the older and no longer working methods are still accessible for the `event` with autocompletion because of their types, and the way of knowing they're deprecated is by running the app and seeing the error message, this should improve that when coding in tools like VS Code.
## Feature
- [ ] Implements an existing feature request or RFC. Make sure the feature request has been accepted for implementation before opening a PR.
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [x] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [ ] Errors have helpful link attached, see `contributing.md`
## Documentation / Examples
- [ ] Make sure the linting passes by running `yarn lint`
Co-authored-by: JJ Kasper <22380829+ijjk@users.noreply.github.com>
* fix: update default redirect status to 307 to match docs
* fix: update default redirect status to 307 to match docs
Co-authored-by: JJ Kasper <jj@jjsweb.site>
We currently have inconsistencies when working with URLs in the Edge Functions runtime, this PR addresses them introducing a warning for inconsistent usage that will break in the future. Here is the reasoning.
### The Browser
When we are in a browser environment there is a fixed location stored at `globalThis.location`. Then, if one tries to build a request with a relative URL it will work using that location global hostname as _base_ to construct its URL. For example:
```typescript
// https://nextjs.org
new Request('/test').url; // https://nextjs.org/test
Response.redirect('/test').headers.get('Location'); // https://nextjs.org/test
```
However, if we attempt to run the same code from `about:blank` it would not work because the global to use as a base `String(globalThis.location)` is not a valid URL. Therefore a call to `Response.redirect('/test')` or `new Response('/test')` would fail.
### Edge Functions Runtime
In Next.js Edge Functions runtime the situation is slightly different from a browser. Say that we have a root middleware (`pages/_middleware`) that gets invoked for every page. In the middleware file we expose the handler function and also define a global variable that we mutate on every request:
```typescript
// pages/_middleware
let count = 0;
export function middleware(req: NextRequest) {
console.log(req.url);
count += 1;
}
```
Currently we cache the module scope in the runtime so subsequent invocations would hold the same globals and the module would not be evaluated again. This would make the counter to increment for each request that the middleware handles. It is for this reason that we **can't have a global location** that changes across different invocations. Each invocation of the same function uses the same global which also holds primitives like `URL` or `Request` so changing an hypothetical `globalThis.location` per request would affect concurrent requests being handled.
Then, it is not possible to use relative URLs in the same way the browser does because we don't have a global to rely on to use its host to compose a URL from a relative path.
### Why it works today
We are **not** validating what is provided to, for example, `NextResponse.rewrite()` nor `NextResponse.redirect()`. We simply create a `Response` instance that adds the corresponding header for the rewrite or the redirect. Then it is **the consumer** the one that composes the final destination based on the request. Theoretically you can pass any value and it would fail on redirect but won't validate the input.
Of course this is inconsistent because it doesn't make sense that `NextResponse.rewrite('/test')` works but `fetch(new NextRequest('/test'))` does not. Also we should validate what is provided. Finally, we want to be consistent with the way a browser behaves so `new Request('/test')` _should_ not work if there is no global location which we lack.
### What this PR does
We will have to deprecate the usage of relative URLs in the previously mentioned scenarios. In preparation for it, this PR adds a validation function in those places where it will break in the future, printing a warning with a link that points to a Next.js page with an explanation of the issue and ways to fix it.
Although middleware changes are not covered by semver, we will roll this for some time to make people aware that this change is coming. Then after a reasonable period of time we can remove the warning and make the code fail when using relative URLs in the previously exposed scenarios.
# Description
The redirect responses do not contain a message body. This is in conflict with the RFCs (below) and causes Traefik (a reverse proxy) to invalidate the responses. In this pull request, I add a response body to the redirect responses.
This PR is similar to https://github.com/vercel/next.js/pull/25257, it appears that there are some other locations where redirection is handled incorrectly in next.js.
# References
- https://datatracker.ietf.org/doc/html/rfc7230#section-3.3
> All 1xx (Informational), 204 (No Content), and 304 (Not Modified) responses must not include a message-body. All other responses do include a message-body, although the body may be of zero length.
- https://datatracker.ietf.org/doc/html/rfc7231#section-6.4.3
> The server's response payload usually contains a short hypertext note with a hyperlink to the different URI(s).
Co-authored-by: JJ Kasper <22380829+ijjk@users.noreply.github.com>
This ensures type checking passes correctly for middleware types when `skipLibCheck: false` is set in `tsconfig.json`. This also moves the `middleware-types` to be an isolated test to ensure it isn't relying on any monorepo dependencies.
## Bug
- [x] Related issues linked using `fixes #number`
- [x] Integration tests added
- [ ] Errors have helpful link attached, see `contributing.md`
Fixes: https://github.com/vercel/next.js/issues/31992#issuecomment-984174872
* fix(types): add missing ua type for NextRequest
add missing ua string type on NextRequest["ua"], returns full agent as string
* Update UserAgent type
Co-authored-by: JJ Kasper <jj@jjsweb.site>
This allows TypeScript users to have type safety for middleware functions.
- Closes#30490
Co-authored-by: Lee Robinson <9113740+leerob@users.noreply.github.com>
Co-authored-by: JJ Kasper <22380829+ijjk@users.noreply.github.com>
Previously `response.cookie(name, value, options)` would mutate the passed in `options` which lead to unexpected behaviour as described in #31666.
This PR clones the `options` argument before mutating it.
## Bug
- [x] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have helpful link attached, see `contributing.md`
## Feature
- [ ] Implements an existing feature request or RFC. Make sure the feature request has been accepted for implementation before opening a PR.
- [x] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [ ] Errors have helpful link attached, see `contributing.md`
## Documentation / Examples
- [x] Make sure the linting passes by running `yarn lint`
This PR adds support for [Middleware as per RFC ](https://github.com/vercel/next.js/discussions/29750).
## Feature
- [ ] Implements an existing feature request or RFC. Make sure the feature request has been accepted for implementation before opening a PR.
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [ ] Errors have helpful link attached, see `contributing.md`
## Documentation / Examples
- [ ] Make sure the linting passes