There's been some confusion on the correct way to add a `nonce`, so took the opportunity here to:
- Add a new docs page for Content Security Policy
- Explained how to generate a `nonce` with Middleware
- Showed how to consume the `nonce` in a route with `headers`
- Updated the `with-strict-csp` example
- Update the `nonce` error message page
- Backlinked to the new page in a few places in the docs
We initially wrote the [React
page](https://nextjs.org/docs/getting-started/react-essentials) to
introduce Server Components in the App Router, but over time, some
implementation details have changed, and the information has become
stale. The React team is working on adding new docs, so I'd like to
change the narrative on the Next.js docs from "client vs. server
components" to "writing code for the server and for the client" - and
link back to the React documentation when it becomes available.
As React developers, we're very familiar with writing code for the
client, it's nice and simple. But doing so comes at the expense of not
being familiar with the server. The aim of these docs is to help
developers become proficient in both the client and server environments.
I'd like to take it back to the foundations, and not use abstractions
like SSG and CSR, MPAs or SPAs, as those terms come with their own set
of assumptions that make it harder to understand how RSC works. Instead,
we'll focus on the request lifecycle, show how application code flows
from the server to the client, and discuss the trade-offs of doing
operations in each environment.
- [x] Page: Rendering Fundamentals
- [x] Environments: Client and Server
- [x] Request-response lifecycle
- [x] Network Boundary
- [x] Page: Server Components
- [x] Benefits and use cases of server rendering
- [x] How to use Server Components in Next.js
- [x] How Server Components are rendered
- [x] Static Rendering
- [x] Dynamic Rendering
- [x] Streaming
- [x] Page: Client Components
- [x] Benefits and use cases of client rendering
- [x] How to use Client Components in Next.js
- [x] How Client Components are rendered
- [x] Initial vs. Subsquent navigation
- [x] Page: Composition Patterns
- [x] When to use client and server components
- [x] Server Component Patterns
- [x] Client Component Patterns
- [x] Interleaving Client and Server Components
- [ ] ~Diagrams~ will follow up with new PR.
- [x] Set up redirects: https://github.com/vercel/front/pull/24917
---------
Co-authored-by: Térence Hollander <hollanderterence@gmail.com>
Co-authored-by: shawnthwei <32075290+shawnthwei@users.noreply.github.com>
Co-authored-by: Michael Novotny <manovotny@gmail.com>
Partial fix for #54012: do not generate a blur image in the image loader when the image is detected to be animated, rather than returning the *entire* animated image as the blur image.
## For Contributors
### Improving Documentation
- [x] Run `pnpm prettier-fix` to fix formatting issues before opening the PR.
- [x] Read the Docs Contribution Guide to ensure your contribution follows the docs guidelines: https://nextjs.org/docs/community/contribution-guide
### What?
Add instructions for using `bun/bunx` where relevant. I only added mentions where npm/yarn/pnpm were all already listed.
### Why
Bun can be used as a runtime-agnostic [package manager](https://bun.sh/package-manager) and script runner in any project with a `package.json`.
(Sorry, I probably should have consolidated this with https://github.com/vercel/next.js/pull/53467)
Co-authored-by: Steven <229881+styfle@users.noreply.github.com>
When using imports from `next/headers` in a layout or page,
`StaticGenerationBailout` will throw an error to indicate Next.js should
fallback to dynamic rendering. However, when async context is lost, this
error is uncaught and leads to a confusing error message at build time.
This attempts to improve DX surrounding this error by linking out to a
page that explains when it might happen. I've also tweaked
`StaticGenerationBailout` to always throw a fully descriptive reason as
opposed to just `DynamicServerError: Dynamic server usage: cookies`
Closes NEXT-1181
Fixes#49373
---------
Co-authored-by: Lee Robinson <me@leerob.io>
Co-authored-by: kodiakhq[bot] <49736102+kodiakhq[bot]@users.noreply.github.com>
This PR document the caching semantics in Next.js, how they interact, and what APIs affect them. We're also taking the opportunity to consolidate terminology, remove duplicate content, and update sections of the docs that relate to caching.
### Documentation
- [x] Create a new section for caching
- [x] Explain how the different caching mechanisms work
- [x] Request Memoization (React Cache)
- [x] Persistent Data Cache
- [x] Persistent Full Route Cache
- [x] In-memory, client-side Router Cache
- [x] Document how different APIs affect caching
- [x] Document cache interactions
- [x] Clean up stale information in the other docs sections
- [x] Routing Section
- [x] Move advanced navigation topics from fundamentals to **How Navigation Works** section
- [x] Rewrite the **How Navigation Works** section
- [x] Rendering Section
- [x] Simplify fundamentals page
- [x] Rewrite the **Static and Dynamic Rendering** pages
- [ ] ~Create a page to explain how **Client and Server Components** are rendered~. Moved to this PR: https://github.com/vercel/next.js/pull/51579
- [x] Data fetching section
- [x] Consolidate data fetching story for fetching, caching, and revalidating
- [x] Clarify data fetching story with 3rd party libraries and React `cache`
- [x] Create **Data Fetching Patterns** page
- [x] Document other related behaviors:
- [x] Update information on scroll position for back/forward navigation
- [x] Remove the concepts of **soft and hard navigation**
- [x] Remove the concepts of **static and dynamic data fetching**
- [x] Use consistent terminology **runtime** 👉🏼 **request time**. Runtime for Edge and Node.js, request time to describe when dynamic stuff happens
- [x] `generateStaticParams` being able to seed the Full Route Cache
- [x] Polish 💅🏼
---
### Related PRs:
- Diagrams: https://github.com/vercel/front/pull/24142
- Redirects: https://github.com/vercel/front/pull/24179
Previously, this warning message assumed the user knew what `yarn` was and had it installed.
This PR changes the warning message to assume the user knows what `npm` is and has it installed, since `npm` ships with the official `node` installation.
At my work, we use Cloudflare as our CDN, and it has various optimization options for the served code including the "Auto Minify" feature that can minify JS, HTML and CSS to reduce download speed. After months of trying to update React to version 18, I have finally found out that the "Auto Minify" was the root cause of the problem, not anything in our code such as invalid tag nesting or printing dates. Because of that, I thought it would be helpful to add CDN as a possible place for investigating hydration errors.
Co-authored-by: Steven <229881+styfle@users.noreply.github.com>
### What?
Update docs for Google Analytics 4
### Why?
This page doesn't make it clear which script is recommended, and has code that's outdated and erroring.
### How?
Update headings and clean up bad code.
### What?
Add all available options to cli commands
Consistent formatting for all options
### Why?
Options were not consistent across all commands, some were missing
Co-authored-by: Steven <229881+styfle@users.noreply.github.com>
Co-authored-by: JJ Kasper <22380829+ijjk@users.noreply.github.com>
Tweak code owners after some testing and feedback.
- Move the Next.js team up to be optional global code owners (so that everyone can review but are not tagged for review). Global individuals should still be tagged if there are no specific `.vercel.approvers` files in subdirectories.
- Adds @vercel/devex to image files so there's coverage on those files for the docs
- Target specific folder and files for Styfle to get notified
- Deletes some rules in the old GitHub codeowners
The error `next-router-not-mounted` can also happen when one tries to use the `next/router` hook inside the app directory. The error page has been updated to reflect that, and migration guides are linked.
Closes#47038.
Move as much of codeowners as possible to use Vercel Spaces.
1. Makes `@timneutkens @ijjk @shuding @huozhi @feedthejim` global owners
2. Make the `@vercel/next-js` team _optional_ owners of **/docs**,
**/errors**, and **/contributing**, makes team owners of a few packages
as per old config.
3. Make `@vercel/devex` (docs and devrel) owners of **/docs**,
**/errors**, and **/contributing**
4. Make `@vercel/devrel` (devrel only) owners of **/examples**
5. Make `@vercel/web-tooling` owners of specific files and folders (as
per old config)
Leaves @styfle as owner of **image** files on the old config since this
pattern `/**/*image*/** ` can't be used with Vercel Spaces.
Note: We cannot add * or / at the end of files.
[Docs](https://spaces-docs.vercel.sh/docs/code-owners#:~:text=Code%20Owners%20files%20are%20meant%20to%20encourage%20distributed%20ownership%20definitions%20across%20a%20codebase.)
We have reports of users scrolling down the the bottom to copy/paste `domains` configuration, instead of using the safer `remotePatterns` configuration at the top.
This PR collapses the older `domains` configuration behind a details toggle since it is only needed for older versions of Next.js prior to 12.3.0
### What?
Adds a warning when `useSearchParams` deopts the entire page to
client-side rendering.
When there is no Suspense boundary the entire page becomes client-side
rendered, you can learn more about that here:
https://beta.nextjs.org/docs/api-reference/use-search-params#static-rendering
### Why?
We've seen a few cases where people accidentally deopt the entire page
by calling `useSearchParams` as there was no indicator that this deopt
happened.
### How?
When the full page deopt happens the error is caught by the rendering
code so we warn there.
Closes NEXT-589
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- Documentation added
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- Errors have a helpful link attached, see
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## For Maintainers
- Minimal description (aim for explaining to someone not on the team to
understand the PR)
- When linking to a Slack thread, you might want to share details of the
conclusion
- Link both the Linear (Fixes NEXT-xxx) and the GitHub issues
- Add review comments if necessary to explain to the reviewer the logic
behind a change
### What?
### Why?
### How?
Closes NEXT-
Fixes #
-->
Currently all helper functions are exported from huge utils files. This
moves the helper functions to their own files, this approach aligns
better with the rest of the codebase.
The unit tests are split up and colocated with the function it tests.
Also added some missing tests.
Plus some overall cleanup, added comments and fixed types.
## Bug
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have a helpful link attached, see
[`contributing.md`](https://github.com/vercel/next.js/blob/canary/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`
- [ ]
[e2e](https://github.com/vercel/next.js/blob/canary/contributing/core/testing.md#writing-tests-for-nextjs)
tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [ ] Errors have a helpful link attached, see
[`contributing.md`](https://github.com/vercel/next.js/blob/canary/contributing.md)
## Documentation / Examples
- [ ] Make sure the linting passes by running `pnpm build && pnpm lint`
- [ ] The "examples guidelines" are followed from [our contributing
doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)
Changes ESLint warning message to still encourage usage of `next/image`
for the best experience, but also denoting that optimization could come
with incurred costs.
## Feature
- [x] Documentation added
- [x] Errors have a helpful link attached, see
[`contributing.md`](https://github.com/vercel/next.js/blob/canary/contributing.md)
## Documentation / Examples
- [x] Make sure the linting passes by running `pnpm build && pnpm lint`
- [x] The "examples guidelines" are followed from [our contributing
doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)
---------
Co-authored-by: Steven Tey <stevensteel97@gmail.com>
Co-authored-by: Steven <steven@ceriously.com>
The example still has an `<a>` inside the `<Link>` which was deprecated
with next 13.
Current page: https://nextjs.org/docs/messages/link-no-children
<!--
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## Documentation / Examples
- [x] Make sure the linting passes by running `pnpm build && pnpm lint`
- [x] The "examples guidelines" are followed from [our contributing
doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)
---------
Co-authored-by: JJ Kasper <jj@jjsweb.site>
Co-authored-by: Tim Neutkens <tim@timneutkens.nl>
I was notified that this link is broken.
Not sure if I'm missing something, but the Markdown doesn't look right, changed it to be a normal link.
## Documentation / Examples
- [x] Make sure the linting passes by running `pnpm build && pnpm lint`
- [x] The "examples guidelines" are followed from [our contributing doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)
Add `contentDispositionType` config to Image Optimization API so the user can configure `inline` vs `attachment`.
This is recommended when `dangerouslyAllowSVG` is enabled but can also be used when its disabled.
Enables using `next/font` by adding `@next/font` as a dependency and
reexporting its loaders.
Always generates the `font-loader-manifest` as we can't know beforehand
if the user intends to use `next/font` or not.
Also adds telemetry for `next/font` usage.
The tests are updated to use `next/font`. But `@next/font` is tested in
`test/e2e/next-font/index.test.ts` and `test/e2e/app-dir/next-font` as
well to ensure it doesn't break.
Fixes NEXT-351
## Bug
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have a helpful link attached, see
[`contributing.md`](https://github.com/vercel/next.js/blob/canary/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`
- [ ]
[e2e](https://github.com/vercel/next.js/blob/canary/contributing/core/testing.md#writing-tests-for-nextjs)
tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [ ] Errors have a helpful link attached, see
[`contributing.md`](https://github.com/vercel/next.js/blob/canary/contributing.md)
## Documentation / Examples
- [ ] Make sure the linting passes by running `pnpm build && pnpm lint`
- [ ] The "examples guidelines" are followed from [our contributing
doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)
This adds updated matching handle for the server to separate out the matching and executing of different route types e.g. page routes, API routes, and app routes.
Co-authored-by: JJ Kasper <22380829+ijjk@users.noreply.github.com>
This adds a new section about local overrides, as I ran into this error and it took me ages to figure out what was going wrong
Co-authored-by: JJ Kasper <22380829+ijjk@users.noreply.github.com>
Co-authored-by: Tim Neutkens <tim@timneutkens.nl>
Co-authored-by: Steven <steven@ceriously.com>
Co-authored-by: kodiakhq[bot] <49736102+kodiakhq[bot]@users.noreply.github.com>
Currently there's a bug when selecting Chinese, Japanese or Korean (CJK)
as subsets.
```js
const notoSans = Noto_Sans_JP({
subsets: ['japanese'],
})
```
It actually doesn't work, nothing preloads. This PR solves this by
removing CJK languages as candidates for preloading. The reason is that
they contain so many glyphs that each font-family is split up in 100+
font files. It doesn't make sense to preload all of them.
So CJK users will have to disable preloading.
```js
const notoSansJapanese = Noto_Sans_JP({
weight: '400',
preload: false,
})
```
In case you do manually disable preloading like above, the default
`font-display` is changed to `swap`.
This PR also improves the validation errors of subsets.
1. Providing unknown subset
```
`@next/font` error:
Unknown subset `japanese` for font `Inter`.
Available subsets: `cyrillic`, `cyrillic-ext`, `greek`, `greek-ext`, `latin`, `latin-ext`, `vietnamese`
```
2. Missing specified subset. The error has a link with further
instructions.
```
`@next/font` error:
Missing selected subsets for font `Inter`. Please specify subsets in the function call or in your `next.config.js`. Read more: https://nextjs.org/docs/messages/google-fonts-missing-subsets
```
fixes NEXT-336
## Bug
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have a helpful link attached, see
[`contributing.md`](https://github.com/vercel/next.js/blob/canary/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`
- [ ]
[e2e](https://github.com/vercel/next.js/blob/canary/contributing/core/testing.md#writing-tests-for-nextjs)
tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [ ] Errors have a helpful link attached, see
[`contributing.md`](https://github.com/vercel/next.js/blob/canary/contributing.md)
## Documentation / Examples
- [ ] Make sure the linting passes by running `pnpm build && pnpm lint`
- [ ] The "examples guidelines" are followed from [our contributing
doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)
### Description
* Gives us [Vercel] more SEO juice rather than GitHub.
* Gives us the freedom to control GitHub repo file structure independent from URLs.
## Feature
- [x] Documentation added
Similar to https://github.com/vercel/next.js/pull/42106. Make
`@next/font` works as expected when using `transpilePackages`.
Also makes sure `@next/font` is auto-configured correctly when in a
monorepo.
## Bug
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have a 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 a helpful link attached, see `contributing.md`
## Documentation / Examples
- [ ] Make sure the linting passes by running `pnpm build && pnpm lint`
- [ ] The "examples guidelines" are followed from [our contributing
doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)
Co-authored-by: JJ Kasper <jj@jjsweb.site>
After speaking with @timneutkens, this PR provides a smoother experience to users trying to migrate over to app without affecting users in pages.
This PR adds a new export available from `next/compat/router` that exposes a `useRouter()` hook that can be used in both `app/` and `pages/`. It differs from `next/router` in that it does not throw an error when the pages router is not mounted, and instead has a return type of `NextRouter | null`. This allows developers to convert components to support running in both `app/` and `pages/` as they are transitioning over to `app/`.
A component that before looked like this:
```tsx
import { useRouter } from 'next/router';
const MyComponent = () => {
const { isReady, query } = useRouter();
// ...
};
```
Will error when converted over to `next/compat/router`, as `null` cannot be destructured. Instead, developers will be able to take advantage of new hooks:
```tsx
import { useEffect } from 'react';
import { useRouter } from 'next/compat/router';
import { useSearchParams } from 'next/navigation';
const MyComponent = () => {
const router = useRouter() // may be null or a NextRouter instance
const searchParams = useSearchParams()
useEffect(() => {
if (router && !router.isReady) {
return
}
// In `app/`, searchParams will be ready immediately with the values, in
// `pages/` it will be available after the router is ready.
const search = searchParams.get('search')
// ...
}, [router, searchParams])
// ...
}
```
This component will now work in both `pages/` and `app/`. When the component is no longer used in `pages/`, you can remove the references to the compat router:
```tsx
import { useSearchParams } from 'next/navigation';
const MyComponent = () => {
const searchParams = useSearchParams()
// As this component is only used in `app/`, the compat router can be removed.
const search = searchParams.get('search')
// ...
}
```
Note that as of Next.js 13, calling `useRouter` from `next/router` will throw an error when not mounted. This now includes an error page that can be used to assist developers.
We hope to introduce a codemod that can convert instances of your `useRouter` from `next/router` to `next/compat/router` in the future.
Co-authored-by: JJ Kasper <22380829+ijjk@users.noreply.github.com>
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## Bug
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have a 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 a helpful link attached, see `contributing.md`
## Documentation / Examples
- [ ] Make sure the linting passes by running `pnpm build && pnpm lint`
- [ ] The "examples guidelines" are followed from [our contributing
doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)
Updated minimum React version to match information at https://nextjs.org/blog/next-13. This page is the first Google result for "next.js 13 react 17" and the info in it is out of data after Next.js 13 was released.
## Documentation / Examples
- [x] Make sure the linting passes by running `pnpm build && pnpm lint`
- [x] The "examples guidelines" are followed from [our contributing doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)
Adds an error that was missing. Link to beta until the changes are live.
closes#41900
## Bug
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have a 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 a helpful link attached, see `contributing.md`
## Documentation / Examples
- [ ] Make sure the linting passes by running `pnpm lint`
- [ ] The "examples guidelines" are followed from [our contributing
doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)
Co-authored-by: JJ Kasper <jj@jjsweb.site>
Co-authored-by: Matt Kane <m@mk.gg>
Co-authored-by: Ismael <ismael.rumzan@gmail.com>
Co-authored-by: Balázs Orbán <info@balazsorban.com>
This PR adds a new configure property, `images.loaderFile` that allow
you to define a path to a file with an exported image loader function.
This is useful when migrating from `next/legacy/image` to `next/image`
because it lets you configure the loader for every instance of
`next/image` once, similar to the legacy "built-in loaders".
The `target: serverless` config was deprecated a year ago starting in
[Next.js 12](https://nextjs.org/blog/next-12).
Tests were disabled in #41252 so we can now remove `target: serverless`
and all usage of `target` in `next.config.js`.
Co-authored-by: Balázs Orbán <info@balazsorban.com>
Co-authored-by: JJ Kasper <jj@jjsweb.site>
## 📖 What's in there?
This is a follow-up for https://github.com/vercel/next.js/pull/40180
Someone made the good point that users may get directed to this error page while setting up middleware matchers. And that page has no information (yet) about it.
## Documentation / Examples
- [ ] Make sure the linting passes by running `pnpm lint`
- [x] The "examples guidelines" are followed from [our contributing doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)
Co-authored-by: Balázs Orbán <18369201+balazsorban44@users.noreply.github.com>
## 🐛 What's in there?
`foo instanceof Function` is wrongly considered as Dynamic code evaluation by our static analyzer.
This PR fixes it.
- [ ] Related issues linked using `fixes #number`
- [x] Integration tests added
- [x] Errors have a helpful link attached, see `contributing.md`
## 🧪 How to reproduce?
1. Create a simple repro in `examples` folder:
```js
// examples/instance-of-function/pages/index.js
export default function Home() {
return <h1>home</h1>
}
// examples/instance-of-function/middleware.js
import { NextResponse } from 'next/server'
export default async function handler() {
console.log('is arrow a function?', (() => {}) instanceof Function)
return NextResponse.next()
}
```
1. build with next `pnpm next build examples/instance-of-function`
> the build fails
1. rebuild next to include PR's fix `pnpm build`
1. build with new next `pnpm next build examples/instance-of-function`
> the build works
## 📔 Notes to reviewers
`hooks.expression.for(`${prefix}Function`).tap(NAME, handleExpression)` is actually legacy code from the original implementation. It's used when finding `Function` regardless of how it is used. We only want to find `new Function()` or `Function()`, which `hooks.calls` and `hooks.new` are covering.
`eval instanceof Function` is perfectly legit code on the edge, despite its uselessness :lol-think:
Because we got multiple people asking "how do I relax this error when my code contains unreachable dynamic code evaluation", I've copy-pasted details about `config.unstable_allowDynamic` into the error page. Because users do not always click links :blob_shrug:
Adds build error when using font loaders with babel. Otherwise you'll
get other unrelated errors.
## Bug
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have a 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 a helpful link attached, see `contributing.md`
## Documentation / Examples
- [ ] Make sure the linting passes by running `pnpm lint`
- [ ] The "examples guidelines" are followed from [our contributing
doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)
Co-authored-by: JJ Kasper <jj@jjsweb.site>
Partially addresses #41111
## Bug
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have a 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 a helpful link attached, see `contributing.md`
## Documentation / Examples
- [ ] Make sure the linting passes by running `pnpm lint`
- [ ] The "examples guidelines" are followed from [our contributing doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)
Co-authored-by: JJ Kasper <22380829+ijjk@users.noreply.github.com>
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## Bug
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have a 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 a helpful link attached, see `contributing.md`
## Documentation / Examples
- [ ] Make sure the linting passes by running `pnpm lint`
- [ ] The "examples guidelines" are followed from [our contributing
doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)
Co-authored-by: JJ Kasper <jj@jjsweb.site>
I had the same issue, so the fix that worked for me was pulled from this
thread https://stackoverflow.com/a/71870995
I have been experiencing the same problem lately with NextJS and i am
not sure if my observations are applicable to other libraries. I had
been wrapping my components with an improper tag that is, NextJS is not
comfortable having a p tag wrapping your divs, sections etc so it will
yell "Hydration failed because the initial UI does not match what was
rendered on the server". So I solved this problem by examining how my
elements were wrapping each other. With material UI you would need to be
cautious for example if you use a Typography component as a wrapper, the
default value of the component prop is "p" so you will experience the
error if you don't change the component value to something semantic. So
in my own opinion based on my personal experience the problem is caused
by improper arrangement of html elements and to solve the problem in the
context of NextJS one will have to reevaluate how they are arranging
their html element
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## Documentation / Examples
- [x] Make sure the linting passes by running `pnpm lint`
- [ ] The "examples guidelines" are followed from [our contributing
doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)
Co-authored-by: JJ Kasper <jj@jjsweb.site>
Continues #39778Closes#40499
## Bug
- [ ] 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 `pnpm lint`
- [ ] The examples guidelines are followed from [our contributing
doc](https://github.com/vercel/next.js/blob/canary/contributing.md#adding-examples)
Co-authored-by: Tim Neutkens <tim@timneutkens.nl>
Co-authored-by: JJ Kasper <jj@jjsweb.site>
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## Bug
- [ ] 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 `pnpm lint`
- [ ] The examples guidelines are followed from [our contributing
doc](https://github.com/vercel/next.js/blob/canary/contributing.md#adding-examples)
Co-authored-by: Balázs Orbán <info@balazsorban.com>
## Summary
This PR adds a note about how to see the data that this error is complaining about:
```sh
Warning: data for page "/" is xxx which exceeds the threshold of 128 kB, this amount of data can reduce performance.
```
This debug trick was something I came across in a [discussion](https://github.com/vercel/next.js/discussions/39880) and I thought it would be helpful to others like it was for me.
## Documentation / Examples
- [ ] Make sure the linting passes by running `pnpm lint`
- [ ] The examples guidelines are followed from [our contributing doc](https://github.com/vercel/next.js/blob/canary/contributing.md#adding-examples)
Co-authored-by: JJ Kasper <22380829+ijjk@users.noreply.github.com>
### 📖 What's in there?
Dynamic code evaluation (`eval()`, `new Function()`, ...) is not
supported on the edge runtime, hence why we fail the build when
detecting such statement in the middleware or `experimental-edge` routes
at build time.
However, there could be false positives, which static analysis and
tree-shaking can not exclude:
- `qs` through these dependencies (get-intrinsic:
[source](https://github.com/ljharb/get-intrinsic/blob/main/index.js#L12))
- `function-bind`
([source](https://github.com/Raynos/function-bind/blob/master/implementation.js#L42))
- `has`
([source](https://github.com/tarruda/has/blob/master/src/index.js#L5))
This PR leverages the existing `config` export to let user allow some of
their files.
it’s meant for allowing users to import 3rd party modules who embed
dynamic code evaluation, but do not use it (because or code paths), and
can't be tree-shaked.
By default, it’s keeping the existing behavior: warn in dev, fails to
build.
If users allow dynamic code, and that code is reached at runtime, their
app stills breaks.
### 🧪 How to test?
- (existing) integration tests for disallowing dynamic code evaluation:
`pnpm testheadless --testPathPattern=runtime-dynamic`
- (new) integration tests for allowing dynamic code evaluation: `pnpm
testheadless --testPathPattern=runtime-configurable`
- (amended) production tests for validating the new configuration keys:
`pnpm testheadless --testPathPattern=config-validations`
To try it live, you could have an application such as:
```js
// lib/index.js
/* eslint-disable no-eval */
export function hasUnusedDynamic() {
if ((() => false)()) {
eval('100')
}
}
export function hasDynamic() {
eval('100')
}
// pages/index.jsx
export default function Page({ edgeRoute }) {
return <p>{edgeRoute}</p>
}
export const getServerSideProps = async (req) => {
const res = await fetch(`http://localhost:3000/api/route`)
const data = await res.json()
return { props: { edgeRoute: data.ok ? `Hi from the edge route` : '' } }
}
// pages/api/route.js
import { hasDynamic } from '../../lib'
export default async function handle() {
hasDynamic()
return Response.json({ ok: true })
}
export const config = {
runtime: 'experimental-edge' ,
allowDynamic: '/lib/**'
}
```
Playing with `config.allowDynamic`, you should be able to:
- build the app even if it uses `eval()` (it will obviously fail at
runtime)
- build the app that _imports but does not use_ `eval()`
- run the app in dev, even if it uses `eval()` with no warning
### 🆙 Notes to reviewers
Before adding documentation and telemetry, I'd like to collect comments
on a couple of points:
- the overall design for this feature: is a list of globs useful and
easy enough?
- should the globs be relative to the application root (current
implementation) to to the edge route/middleware file?
- (especially to @sokra) is the implementation idiomatic enough? I've
leverage loaders to read the _entry point_ configuration once, then the
ModuleGraph to get it back during the parsing phase. I couldn't re-use
the existing `getExtractMetadata()` facility since it's happening late
after the parsing.
- there's a glitch with `import { ServerRuntime } from '../../types'` in
`get-page-static-info.ts`
([here](https://github.com/vercel/next.js/pull/39539/files#diff-cb7ac6392c3dd707c5edab159c3144ec114eafea92dad5d98f4eedfc612174d2L12)).
I had to use `next/types` because it was failing during lint. Any clue
why?
### ☑️ Checklist
- [ ] 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
- [x] Telemetry added. In case of a feature if it's used or not.
- [x] Errors have helpful link attached, see `contributing.md`
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This serves to add support for [Subresource
Integrity](https://developer.mozilla.org/en-US/docs/Web/Security/Subresource_Integrity)
hashes for scripts added from the new app directory. This also has
support for utilizing nonce values passed from request headers (expected
to be generated per request in middleware) in the bootstrapping scripts
via the `Content-Security-Policy` header as such:
```
Content-Security-Policy: script-src 'nonce-2726c7f26c'
```
Which results in the inline scripts having a new `nonce` attribute hash
added. These features combined support for setting an aggressive Content
Security Policy on scripts loaded.
## Bug
- [ ] 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.
- [x] Errors have helpful link attached, see `contributing.md`
## Documentation / Examples
- [x] Make sure the linting passes by running `pnpm lint`
- [x] The examples guidelines are followed from [our contributing
doc](https://github.com/vercel/next.js/blob/canary/contributing.md#adding-examples)
Co-authored-by: Steven <steven@ceriously.com>
