fix server actions behavior on intercepted routes

[ztanner]

What?

When using a server action on an intercepted route, when submitting that action, you'd expect it to correspond with the page you're currently on. However if you have route interception set up, and you load the page rather than the intercepted page, submitting the action would POST to the intercepted page. This would result in a 404 error because the action ID you're attempting to submit wouldn't be found on the requested page.

Why?

Interception routes rely on the Next-Url request header to determine if an interception should occur via a rewrite. However, server actions are submitted with this header as well, so the rewrite will be applied to the POST request corresponding with a non-existent action, or an action on the intercepted page.

How?

When loading a page that has an intercepted route, nextUrl should be consistent with URL derived from the flight router state tree. But when an interception occurs via navigation, nextUrl will now deviate. I'm using this to determine whether or not Next-Url should be forwarded along in the POST request.

Closes NEXT-1436
Fixes #52591
Fixes #49934
Fixes #58049

[ztanner]

Current dependencies on/for this PR:

• canary
  • PR fix server actions behavior on intercepted routes #59175 👈

This stack of pull requests is managed by Graphite.

[ijjk]

Stats from current PR

Default Build

General Overall increase ⚠️

	vercel/next.js canary	vercel/next.js 12-01-fix_server_actions_behavior_on_intercepted_routes	Change
buildDuration	10.6s	10.5s	N/A
buildDurationCached	6s	6s	N/A
nodeModulesSize	199 MB	199 MB	⚠️ +3.2 kB
nextStartRea..uration (ms)	423ms	419ms	N/A

Client Bundles (main, webpack)

	vercel/next.js canary	vercel/next.js 12-01-fix_server_actions_behavior_on_intercepted_routes	Change
199-HASH.js gzip	30.7 kB	30.8 kB	N/A
3f784ff6-HASH.js gzip	53.3 kB	53.3 kB	✓
494.HASH.js gzip	180 B	181 B	N/A
framework-HASH.js gzip	45.2 kB	45.2 kB	✓
main-app-HASH.js gzip	241 B	240 B	N/A
main-HASH.js gzip	31.7 kB	31.7 kB	N/A
webpack-HASH.js gzip	1.7 kB	1.7 kB	✓
Overall change	100 kB	100 kB	✓

Legacy Client Bundles (polyfills)

	vercel/next.js canary	vercel/next.js 12-01-fix_server_actions_behavior_on_intercepted_routes	Change
polyfills-HASH.js gzip	31 kB	31 kB	✓
Overall change	31 kB	31 kB	✓

Client Pages

	vercel/next.js canary	vercel/next.js 12-01-fix_server_actions_behavior_on_intercepted_routes	Change
_app-HASH.js gzip	194 B	195 B	N/A
_error-HASH.js gzip	182 B	181 B	N/A
amp-HASH.js gzip	501 B	503 B	N/A
css-HASH.js gzip	322 B	323 B	N/A
dynamic-HASH.js gzip	2.5 kB	2.5 kB	✓
edge-ssr-HASH.js gzip	253 B	255 B	N/A
head-HASH.js gzip	348 B	347 B	N/A
hooks-HASH.js gzip	369 B	368 B	N/A
image-HASH.js gzip	4.27 kB	4.27 kB	N/A
index-HASH.js gzip	256 B	256 B	✓
link-HASH.js gzip	2.61 kB	2.6 kB	N/A
routerDirect..HASH.js gzip	311 B	311 B	✓
script-HASH.js gzip	384 B	383 B	N/A
withRouter-HASH.js gzip	307 B	308 B	N/A
1afbb74e6ecf..834.css gzip	106 B	106 B	✓
Overall change	3.17 kB	3.17 kB	✓

Client Build Manifests

	vercel/next.js canary	vercel/next.js 12-01-fix_server_actions_behavior_on_intercepted_routes	Change
_buildManifest.js gzip	484 B	483 B	N/A
Overall change	0 B	0 B	✓

Rendered Page Sizes

	vercel/next.js canary	vercel/next.js 12-01-fix_server_actions_behavior_on_intercepted_routes	Change
index.html gzip	527 B	527 B	✓
link.html gzip	539 B	541 B	N/A
withRouter.html gzip	524 B	523 B	N/A
Overall change	527 B	527 B	✓

Edge SSR bundle Size

	vercel/next.js canary	vercel/next.js 12-01-fix_server_actions_behavior_on_intercepted_routes	Change
edge-ssr.js gzip	92.6 kB	92.6 kB	N/A
page.js gzip	145 kB	145 kB	N/A
Overall change	0 B	0 B	✓

Middleware size

	vercel/next.js canary	vercel/next.js 12-01-fix_server_actions_behavior_on_intercepted_routes	Change
middleware-b..fest.js gzip	626 B	626 B	✓
middleware-r..fest.js gzip	150 B	151 B	N/A
middleware.js gzip	35.7 kB	35.7 kB	N/A
edge-runtime..pack.js gzip	1.92 kB	1.92 kB	✓
Overall change	2.55 kB	2.55 kB	✓

Next Runtimes

	vercel/next.js canary	vercel/next.js 12-01-fix_server_actions_behavior_on_intercepted_routes	Change
app-page-exp...dev.js gzip	168 kB	168 kB	✓
app-page-exp..prod.js gzip	93.8 kB	93.8 kB	✓
app-page-tur..prod.js gzip	94.5 kB	94.5 kB	✓
app-page-tur..prod.js gzip	89.1 kB	89.1 kB	✓
app-page.run...dev.js gzip	138 kB	138 kB	✓
app-page.run..prod.js gzip	88.4 kB	88.4 kB	✓
app-route-ex...dev.js gzip	24.2 kB	24.2 kB	✓
app-route-ex..prod.js gzip	16.8 kB	16.8 kB	✓
app-route-tu..prod.js gzip	16.9 kB	16.9 kB	✓
app-route-tu..prod.js gzip	16.4 kB	16.4 kB	✓
app-route.ru...dev.js gzip	23.6 kB	23.6 kB	✓
app-route.ru..prod.js gzip	16.4 kB	16.4 kB	✓
pages-api-tu..prod.js gzip	9.37 kB	9.37 kB	✓
pages-api.ru...dev.js gzip	9.64 kB	9.64 kB	✓
pages-api.ru..prod.js gzip	9.37 kB	9.37 kB	✓
pages-turbo...prod.js gzip	21.9 kB	21.9 kB	✓
pages.runtim...dev.js gzip	22.6 kB	22.6 kB	✓
pages.runtim..prod.js gzip	21.9 kB	21.9 kB	✓
server.runti..prod.js gzip	49.3 kB	49.3 kB	✓
Overall change	930 kB	930 kB	✓

Diff details

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Diff for 199-HASH.js

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Commit: 9e6e338