## What's in there?
The Edge runtime [does not support Node.js modules](https://edge-runtime.vercel.app/features/available-apis#unsupported-apis).
When building Next.js application, we currently fail the build when detecting node.js module imported from middleware.
This is an blocker for using code that is conditionally loading node.js modules (based on platform/env detection), as @cramforce reported.
This PR implements a new strategy where:
- we can build such middleware/Edge API route code **with a warning**
- we fail at run time, with graceful errors in dev (console & react-dev-overlay error)
- we fail at run time, with console errors in production
## How to test?
All cases are covered with integration tests.
To try them live, create a simple app with a page, a `middleware.js` file and a `pages/api/route.js`file.
Here are iconic examples:
### node.js modules
```js
// middleware.js
import { NextResponse } from 'next/server'
// static
import { basename } from 'path'
export default async function middleware() {
// dynamic
const { basename } = await import('path')
basename()
return NextResponse.next()
}
export const config = { matcher: '/' }
```
```js
// pags/api/route.js
// static
import { isAbsolute } from 'path'
export default async function handle() {
// dynamic
const { isAbsolute } = await import('path')
return Response.json({ useNodeModule: isAbsolute('/test') })
}
export const config = { runtime: 'experimental-edge' }
```
Desired error (+ source code highlight in dev):
> The edge runtime does not support Node.js 'path' module
Learn More: https://nextjs.org/docs/messages/node-module-in-edge-runtime
Desired warning at build time:
> A Node.js module is loaded ('path' at line 2) which is not supported in the Edge Runtime.
Learn More: https://nextjs.org/docs/messages/node-module-in-edge-runtime
- [x] in dev middleware, static, shows desired error on stderr
- [x] in dev route, static, shows desired error on stderr
- [x] in dev middleware, dynamic, shows desired error on stderr
- [x] in dev route, dynamic, shows desired error on stderr
- [x] in dev middleware, static, shows desired error on react error overlay
- [x] in dev route, static, shows desired error on react error overlay
- [x] in dev middleware, dynamic, shows desired error on react error overlay
- [x] in dev route, dynamic, shows desired error on react error overlay
- [x] builds middleware successfully, shows build warning, shows desired error on stderr on call
- [x] builds route successfully, shows build warning, shows desired error on stderr on call
### 3rd party modules not found
```js
// middleware.js
import { NextResponse } from 'next/server'
// static
import Unknown from 'unknown'
export default async function middleware() {
// dynamic
const Unknown = await import('unknown')
new Unknown()
return NextResponse.next()
}
```
export const config = { matcher: '/' }
```
```js
// pags/api/route.js
// static
import Unknown from 'unknown'
export default async function handle() {
// dynamic
const Unknown = await import('unknown')
return Response.json({ use3rdPartyModule: Unknown() })
}
export const config = { runtime: 'experimental-edge' }
```
Desired error (+ source code highlight in dev):
> Module not found: Can't resolve 'does-not-exist'
Learn More: https://nextjs.org/docs/messages/module-not-found
- [x] in dev middleware, static, shows desired error on stderr
- [x] in dev route, static, shows desired error on stderr
- [x] in dev middleware, dynamic, shows desired error on stderr
- [x] in dev route, dynamic, shows desired error on stderr
- [x] in dev middleware, static, shows desired error on react error overlay
- [x] in dev route, static, shows desired error on react error overlay
- [x] in dev middleware, dynamic, shows desired error on react error overlay
- [x] in dev route, dynamic, shows desired error on react error overlay
- [x] fails to build middleware, with desired error on stderr
- [x] fails to build route, with desired error on stderr
### unused node.js modules
```js
// middleware.js
import { NextResponse } from 'next/server'
export default async function middleware() {
if (process.exit) {
const { basename } = await import('path')
basename()
}
return NextResponse.next()
}
```
```js
// pags/api/route.js
export default async function handle() {
if (process.exit) {
const { basename } = await import('path')
basename()
}
return Response.json({ useNodeModule: false })
}
export const config = { runtime: 'experimental-edge' }
```
Desired warning at build time:
> A Node.js module is loaded ('path' at line 2) which is not supported in the Edge Runtime.
Learn More: https://nextjs.org/docs/messages/node-module-in-edge-runtime
- [x] invoke middleware in dev with no error
- [x] invoke route in dev with no error
- [x] builds successfully, shows build warning, invoke middleware with no error
- [x] builds successfully, shows build warning, invoke api-route with no error
## Notes to reviewers
The strategy to implement this feature is to leverages webpack [externals](https://webpack.js.org/configuration/externals/#externals) and run a global `__unsupported_module()` function when using a node.js module from edge function's code.
For the record, I tried using [webpack resolve.fallback](https://webpack.js.org/configuration/resolve/#resolvefallback) and [Webpack.IgnorePlugin](https://webpack.js.org/plugins/ignore-plugin/) but they do not allow throwing proper errors at runtime that would contain the loaded module name for reporting.
`__unsupported_module()` is defined in `EdgeRuntime`, and returns a proxy that's throw on use (whether it's property access, function call, new operator... synchronous & promise-based styles).
However there's an issue with error reporting: webpack does not includes the import lines in the generated sourcemaps, preventing from displaying useful errors.
I extended our middleware-plugin to supplement the sourcemaps (when analyzing edge function code, it saves which module is imported from which file, together with line/column/source)
The react-dev-overlay was adapted to look for this additional information when the caught error relates to modules, instead of looking at sourcemaps.
I removed the previous mechanism (built by @nkzawa ) which caught webpack errors at built time to change the displayed error message (files `next/build/index.js`, `next/build/utils.ts` and `wellknown-errors-plugin`)
- Always perform a full reload when needed without blocking with the overlay.
- Old client warnings re-added.
- Post client warning to dev server and print it in the CLI.
## 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)
If you end up in a state where an error happened and you also should be warned about a full refresh - you get stuck. The full refresh is blocked by the warning but the error is shown instead.
Tests didn't catch this because the refresh warning never showed in `__NEXT_TEST_MODE`.
## Bug
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have helpful link attached, see `contributing.md`
### What's in there?
This is a followup of https://github.com/vercel/next.js/pull/37695.
For the dev server to clean stacktraces, we're decorating errors caught during code evaluation (`getServerSideProps` or middleware).
However, when these errors are asynchronously raised, we can't decorate them before processing them, leading to this fallback logic:
bf7bf8217f/packages/next/server/dev/next-dev-server.ts (L775-L779)
Thanks to latest improvement of the edge-runtime in 1.1.0-beta.4, we can now catch unhandled rejection and uncaught exception, and decorate them.
### How to test?
Please reuse the existing tests who already covered these cases:
`pnpm testheadless --testPathPattern middleware-dev-errors`
Co-authored-by: JJ Kasper <22380829+ijjk@users.noreply.github.com>
* Improve stack traces in dev mode
* Refactor `react-dev-overlay` to support the Edge Compiler
* Serialize errors including the compiler `source`
* Adopt the new `react-dev-overlay` displaying it for middleware errors
* Improve tests
* fix rsc cases
* update test
* use check for dev test
* handle different error from node version
Co-authored-by: feugy <damien@vercel.com>
Co-authored-by: JJ Kasper <jj@jjsweb.site>
Follow-up to https://github.com/vercel/next.js/pull/31519 this ensures the error link we added is shown with react 18 as well.
## Documentation / Examples
- [x] Make sure the linting passes by running `yarn lint`
Linked to issue #32209.
## 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
There are three Trusted Types violations that are fixed in this PR:
### 1. ban-element-innerhtml-assignments: maintain--tab-focus.ts
The innerHTML assignment here is unsafe as a string is being used that could contain an XSS attack. The solution chosen was to replace the string containing HTML with programmatically-created DOM elements. This removes the Trusted Types violation as there is no longer a string passed in that can contain an XSS attack.
Notes on solution:
- The `<svg>` tag is omitted completely since the original snippet returns fragment.firstChild.firstChild. The first firstChild omits the `<div>`, and the second firstChild omits the `<svg>`, so to remove unnecessary code the created elements start at the foreignObject level.
- The reason createElementNS is used instead of createElement is because the ‘foreignObject’ element is a separate namespace from the default HTML elements. The documentation for this command is found [here](https://developer.mozilla.org/en-US/docs/Web/API/Document/createElementNS).
The code was tested to be equivalent by rendering both the original code and the re-written code in a browser to see if they evaluate to the same thing in the DOM. The DOM elements styles were then compared to ensure that they were identical.
### 2. ban-window-stringfunctiondef: packages/next/lib/recursive-delete.ts
The setTimeout function caused a Trusted Types violation because if a string is passed in as the callback, XSS can occur. The solution to this problem is to ensure that only function callbacks can be passed to setTimeout. There is only one call to the sleep function and it does not involve a string callback, so this can be enforced without breaking the application logic. In the process of doing this, promisify has been removed and the promise has been created explicitly.
The code was tested in a sample application to ensure it behaved as expected.
### 3. ban-window-stringfunctiondef: packages/next/client/dev/fouc.ts
This file also uses setTimeout, so the call was wrapped in a `safeSetTimeout` call that specifies that the callback argument is not a string.
Report full parsed runtime errors over error bus, accepts preventDisplay prop to avoid showing error messages inline, while still reporting errors over the bus.
Basically, we want to handle the parsed error/stack differently in Next Live, showing a modal that sits above the content and allows users to report the issue to us. We want to have that stack trace in the issue report, so I added a new event `unhandled-error-full`.
The `preventDisplay` prop then just lets us output our own modal instead of showing the error inline, but still renders the `<RuntimeErrors />` component so it can fetch the stack and report it over the bus.
This isn't *beautiful* code per-se, but I think doing it really right would require a pretty intense re-structure of this module. I think ideally we'd have export a function to fetch of the stack that we can just expose separately - that fetch currently happens in a sub-sub-component (DevOverlay > Errors > RuntimeError). But that re-write is pretty high effort, would still require much of what we do here anyway, and would just to get a slightly less awkward API in a not very high-use area. So leaving it as-is for now, happy to revisit though if we want.
## Feature
- [x] Related issues linked using `fixes #number`
Fixes an issue with Next Live #290.
## Documentation / Examples
- [x] Make sure the linting passes by running `yarn lint`
Co-authored-by: JJ Kasper <22380829+ijjk@users.noreply.github.com>
x-ref: #31827
x-ref: #34212
![image](https://user-images.githubusercontent.com/1365881/151994766-b9afb349-1a9a-4220-9387-de10165e34e3.png)
## 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 `yarn lint`
Co-authored-by: JJ Kasper <22380829+ijjk@users.noreply.github.com>
include a few lines of stack trace in the full refresh overlay
error is not necessary webpack related
## 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 `yarn lint`
## Feature
- [x] Implements an existing feature request or RFC. Make sure the feature request has been accepted for implementation before opening a PR.
- [x] Related issue: #14701
- [ ] 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`
<details>
<summary>Screenshot</summary>
<img width="1388" alt="Screen Shot 2021-12-17 at 2 07 04 PM" src="https://user-images.githubusercontent.com/22380829/146602057-9675455d-cf10-435a-b121-bc462a87fbf3.png">
</details>
Closes: https://github.com/vercel/next.js/issues/14701
Co-authored-by: JJ Kasper <22380829+ijjk@users.noreply.github.com>
This adds an error document/link for hydration errors to help users debug these easier. While looking at adding this also noticed a typo in the dev-overlay which is fixed.
<details>
<summary>screenshot</summary>
<img width="1109" alt="Screen Shot 2021-11-16 at 15 56 29" src="https://user-images.githubusercontent.com/22380829/142078200-6c036ed9-ca7f-4d26-ae07-eb9bd89e991a.png">
</details>
## Documentation / Examples
- [x] Make sure the linting passes by running `yarn lint`
Co-authored-by: Tim Neutkens <6324199+timneutkens@users.noreply.github.com>