When opting into caching a POST request with the `revalidate` option, or
when the Server Components HMR Cache implicitly caches a POST request,
the body of the request is now correctly handled if it is a
`Uint8Array`. Previously, we logged `Failed to generate cache key for
...` and the cache was bypassed.
closes NAR-180
In #60645, dynamic access tracking was refactored but we erroneously
stopped tracking dynamic access in route handlers. Request proxying, as
well as tracking segment level configs (such as `export const dynamic =
'force-dynamic'`), were only enabled during static generation. This was
an unintended breaking change that consequently caused dynamic access to
not properly bail from data cache in various circumstances.
This adds some more rigorous testing for route handlers, as this seems
to be a fairly large gap in our fetch cache testing currently.
This PR is easiest to review with [whitespace
disabled](https://github.com/vercel/next.js/pull/66446/files?w=1).
This makes some critical modifications to the app render pipeline when
PPR has been enabled for pages with segments defining:
```js
export const dynamic = "force-dynamic"
```
Importantly, it no longer modifies the revalidation time to zero for
those pages, and now falls back to the provided default revalidation
time. When static render occurs, if the page being rendered has a
segment config defining `dynamic === "force-dynamic"`, then it will
postpone at the root of the component tree. This ensures that no render
code is executed for the page, as the entirety of the tree will have
postponed. This fixes the bug where the flight prefetch wasn't generated
correctly as well.
This ensures we don't unexpectedly error when a fetch attempts to cache
inside of `unstable_cache`, this also ensures `only-on-store` doesn't
unexpectedly error when `revalidate: 0` is set.
This ensures we don't fail to return the full body when storing to
fetch-cache in edge-runtime. Also ensures the fetch cache tests are
running for Node.js v16 correctly.
Fetch handling was also failing on Node.js v16 due to react's use of
`res.clone()` being broken with undici which is fixed in the latest
version of edge-runtime so this bumps that.
x-ref: [slack
thread](https://vercel.slack.com/archives/C03S8ED1DKM/p1681310566927429)
Ensure we handle the use-case where a React Server Component using
`fetch` encounters a `204` response.
---------
Co-authored-by: JJ Kasper <jj@jjsweb.site>
### What?
Change the caching logic for fetch-cache to only cache successful
responses.
### Why?
Currently fetch-cache will cache any response, without checking the http
status code. But situations like 500 and 304 and others should not be
cached, because we want to re-fetch from the origin.
### How?
Add an extra check before deciding to call `incrementalCache.set()`
---------
Co-authored-by: JJ Kasper <jj@jjsweb.site>
This ensures we properly honor the `export const fetchCache` config and
also ensures we properly bypass fetch-cache when an On-Demand
Revalidation is occurring.
The `export const dynamic` handling is not changed here as that was
behaving correctly and should not influence fetch cache handling only
whether a page is prerendered fully or treated as SSR.
Fixes: https://github.com/vercel/next.js/issues/47273
x-ref: [slack
thread](https://vercel.slack.com/archives/C042LHPJ1NX/p1679078572123979)
This updates to no longer skip caching POST or authed requests with the
fetch cache and instead we bail when `cookies()` or `headers()` is used
prior which is a better heuristic to signal user specific data would be
related to the fetch request.
x-ref: [slack
thread](https://vercel.slack.com/archives/C042LHPJ1NX/p1678130069138849)
## Bug
- [x] Related issues linked using `fixes #number`
- [x] Integration tests added
- [ ] Errors have a helpful link attached, see
[`contributing.md`](https://github.com/vercel/next.js/blob/canary/contributing.md)
Sebastian "Sebbie" Silbermann