In #29010, we started throwing an error if the res was mutated after
getServerSideProps() returned. This was to support classic streaming,
where it would be possible to accidentally mutate the response headers
after they were already sent. However, this change also caught [a few
non-streaming cases](https://github.com/vercel/next.js/pull/29010#issuecomment-943482743) that we don't want to break.
As such, with this change, we only throw the error if res is mutated
after gSSP returns *and* you've opted into using classic streaming.
Otherwise, we will only add a warning to the console.
* Throw error if res is accessed after gSSP returns
Currently it's possible to access the `ServerResponse` through `context.res`
in `getServerSideProps()`. If one was to store that response and mutate
its headers or status code after gSSP returns (e.g. during rendering), it
would currently happen to work because of when headers are sent. However,
this is an anti-pattern that relies an implementation detail of the framework
and shouldn't be allowed. This will be particularly important once Next.js
starts to support basic streaming (two-part flush: routing then data) because
then the headers will be sent as soon as gSSP returns, which explicitly breaks
this pattern.
With this commit, the framework now throws an error in development mode if
the ServerResponse is accessed after gSSP returns.
* fixup! Throw error if res is accessed after gSSP returns
Previous to this change, getServerSideProps could only return plain objects
for props, e.g.:
```javascript
export async function getServerSideProps() {
return {
props: {
text: 'some value',
}
}
}
```
With this commit, the props object can also be a Promise, e.g.
```javascript
export async function getServerSideProps() {
return {
props: (async function () {
return {
text: 'promise value',
}
})(),
}
}
```
For now, the framework simply waits for the results of the props Promise to resolve,
but this small change sets the groundwork for later allowing props to be streamed (cc @devknoll).
## Feature
- [x] Implements an existing feature request or RFC. Make sure the feature request has been accepted for implementation before opening a PR. -- *This is part of @devknoll's ongoing work to support streaming.*
- [ ] 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. *not sure if this applies here*
- [ ] Errors have helpful link attached, see `contributing.md`
This PR adds request deduplication for `_getServerData`. If a request with the same URL is already in-flight, we don't send another new request. When a request succeeds or fails, we delete the cache.
A potential improvement this brings is, when `getServerSideProps` of a new route is slow to load, the user might keep clicking on the link which causes new requests, and the route will never update because results of old requests were ditched. Also adds a test case for this scenario.
Closes#19238.
Currently pages with `notFound: false` from `getServerSideProps` behave the same as `notFound: true`, i.e. just having the key is enough to result in a 404. This fixes the check in render.tsx and adds tests for it.
This refactors to instead of throwing a specific error when a SSG data route 404s, we return it through props and render the 404 outside of the error handling flow. No additional tests have been added as existing tests should cover this.
Closes: https://github.com/vercel/next.js/issues/19243
This makes sure we have the correct `asPath` value to prevent breaking hydration for `getServerSideProps` pages and doesn't re-use the `resolvedUrl` value for the `asPath` and instead creates a separate `resolvedAsPath` value that only removes the `_next/data` prefix from the path. Additional tests have been added in the `getServerSideProps` suite to ensure correct `asPath` with rewrites.
Fixes: https://github.com/vercel/next.js/issues/17113
This continues off of https://github.com/vercel/next.js/pull/17081 and provides this normalized `asPath` value in the context provided to `getServerSideProps` to provide the consistent value since the request URL can vary between direct visit and client transition and the alternative requires building the URL each time manually.
Kept this change separate from https://github.com/vercel/next.js/pull/17081 since this is addressing a separate issue and allows discussion separately.
Closes: https://github.com/vercel/next.js/issues/16407
This normalizes the `asPath` for `getServerSideProps` and `getStaticProps` pages to ensure it matches the value that would show on the client instead of a) the output pathname when revalidating or generating a fallback or b) the `_next/data` URL on client transition.
Fixes: https://github.com/vercel/next.js/issues/16542
This updates the named regexes output in the `routes-manifest` and the associated `routeKeys` to not use any non-word characters as this breaks the named regexes e.g. `"Invalid regular expression: "^/(?<data\-provider\-id>[^/]+?)(?:/)?$"`
x-ref: https://github.com/zeit/now/pull/4355
* Verify GS(S)P Serializability
* Add support for cyclic refs
* Add unit tests
* Test for error in development mode
* Fix prerender preview tests
* Fix gssp preview tests
* fix 2x test cases
* Add desired test
* fix some more tests
* Fix route manifest expect
* Fix test expects
* Test that `getServerSideProps` does not error in production
* Test that getStaticProps is not checked in production
* Test serialization check during build
* Fix export detection for serverless
* Update test/unit/is-serializable-props.test.js
Co-Authored-By: JJ Kasper <jj@jjsweb.site>
Co-authored-by: JJ Kasper <jj@jjsweb.site>
* Rename getServerProps to getServerSideProps
* Remove unstable_ prefix from new methods
* Add error when legacy methods are detected
* Add legacy methods for babel transform
* Add unstable_getServerSideProps also
* Apply suggestions from code review
Co-Authored-By: Joe Haddad <joe.haddad@zeit.co>
* Update types import
Co-authored-by: Joe Haddad <timer150@gmail.com>
