Refactor sandbox module cache

[javivelasco]

To run middleware we are using a sandbox that emulates the web runtime and keeps a module cache. This cache is shared for all of the modules that we run using the sandbox while there are some module-level APIs that must be scoped depending on the module we are running.

One example of this is fetch where we want to always inject a special header that indicate the module that is performing the fetch and use it to avoid getting into infinite loops for middleware. For those cases the cached implementation will be the first one that instantiates the module and therefore we can actually get into infinite loops. This is the reason why #31800 is failing.

With this PR we refactor the sandbox so that the module cache is scoped per module name. This means that one execution of a middleware will preserve its cache only for that module so that each execution will still have its own fetch implementation, fixing this issue. Also, with this refactor the code is more clear and we also provide an option to avoid using the cache.

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

[sokra]

a few nitpicks, otherwise fine

[ijjk]

Stats from current PR

Default Build (Increase detected ⚠️)

General Overall increase ⚠️

	vercel/next.js canary	javivelasco/next.js refactor/sandbox-cache	Change
buildDuration	17.4s	17.5s	⚠️ +59ms
buildDurationCached	3.1s	3.1s	⚠️ +27ms
nodeModulesSize	345 MB	345 MB	⚠️ +2.52 kB

Page Load Tests Overall increase ✓

	vercel/next.js canary	javivelasco/next.js refactor/sandbox-cache	Change
/ failed reqs	0	0	✓
/ total time (seconds)	2.812	2.809	0
/ avg req/sec	889.17	890.09	+0.92
/error-in-render failed reqs	0	0	✓
/error-in-render total time (seconds)	1.363	1.336	-0.03
/error-in-render avg req/sec	1834	1870.78	+36.78

Client Bundles (main, webpack, commons)

	vercel/next.js canary	javivelasco/next.js refactor/sandbox-cache	Change
450.HASH.js gzip	179 B	179 B	✓
framework-HASH.js gzip	42.2 kB	42.2 kB	✓
main-HASH.js gzip	28.4 kB	28.4 kB	✓
webpack-HASH.js gzip	1.45 kB	1.45 kB	✓
Overall change	72.2 kB	72.2 kB	✓

Legacy Client Bundles (polyfills)

	vercel/next.js canary	javivelasco/next.js refactor/sandbox-cache	Change
polyfills-HASH.js gzip	31 kB	31 kB	✓
Overall change	31 kB	31 kB	✓

Client Pages

	vercel/next.js canary	javivelasco/next.js refactor/sandbox-cache	Change
_app-HASH.js gzip	1.37 kB	1.37 kB	✓
_error-HASH.js gzip	194 B	194 B	✓
amp-HASH.js gzip	312 B	312 B	✓
css-HASH.js gzip	327 B	327 B	✓
dynamic-HASH.js gzip	2.38 kB	2.38 kB	✓
head-HASH.js gzip	350 B	350 B	✓
hooks-HASH.js gzip	635 B	635 B	✓
image-HASH.js gzip	4.45 kB	4.45 kB	✓
index-HASH.js gzip	263 B	263 B	✓
link-HASH.js gzip	1.87 kB	1.87 kB	✓
routerDirect..HASH.js gzip	321 B	321 B	✓
script-HASH.js gzip	383 B	383 B	✓
withRouter-HASH.js gzip	318 B	318 B	✓
85e02e95b279..7e3.css gzip	107 B	107 B	✓
Overall change	13.3 kB	13.3 kB	✓

Client Build Manifests

	vercel/next.js canary	javivelasco/next.js refactor/sandbox-cache	Change
_buildManifest.js gzip	460 B	460 B	✓
Overall change	460 B	460 B	✓

Rendered Page Sizes

	vercel/next.js canary	javivelasco/next.js refactor/sandbox-cache	Change
index.html gzip	532 B	532 B	✓
link.html gzip	545 B	545 B	✓
withRouter.html gzip	526 B	526 B	✓
Overall change	1.6 kB	1.6 kB	✓

---

Default Build with SWC (Decrease detected ✓)

General Overall increase ⚠️

	vercel/next.js canary	javivelasco/next.js refactor/sandbox-cache	Change
buildDuration	18.9s	19.3s	⚠️ +335ms
buildDurationCached	3.2s	3.2s	⚠️ +65ms
nodeModulesSize	345 MB	345 MB	⚠️ +2.52 kB

Page Load Tests Overall decrease ⚠️

	vercel/next.js canary	javivelasco/next.js refactor/sandbox-cache	Change
/ failed reqs	0	0	✓
/ total time (seconds)	2.737	2.958	⚠️ +0.22
/ avg req/sec	913.56	845.05	⚠️ -68.51
/error-in-render failed reqs	0	0	✓
/error-in-render total time (seconds)	1.242	1.351	⚠️ +0.11
/error-in-render avg req/sec	2012.08	1850.93	⚠️ -161.15

Client Bundles (main, webpack, commons)

	vercel/next.js canary	javivelasco/next.js refactor/sandbox-cache	Change
450.HASH.js gzip	179 B	179 B	✓
framework-HASH.js gzip	42.3 kB	42.3 kB	✓
main-HASH.js gzip	28.6 kB	28.6 kB	✓
webpack-HASH.js gzip	1.44 kB	1.44 kB	✓
Overall change	72.5 kB	72.5 kB	✓

Legacy Client Bundles (polyfills)

	vercel/next.js canary	javivelasco/next.js refactor/sandbox-cache	Change
polyfills-HASH.js gzip	31 kB	31 kB	✓
Overall change	31 kB	31 kB	✓

Client Pages

	vercel/next.js canary	javivelasco/next.js refactor/sandbox-cache	Change
_app-HASH.js gzip	1.35 kB	1.35 kB	✓
_error-HASH.js gzip	180 B	180 B	✓
amp-HASH.js gzip	305 B	305 B	✓
css-HASH.js gzip	321 B	321 B	✓
dynamic-HASH.js gzip	2.37 kB	2.37 kB	✓
head-HASH.js gzip	342 B	342 B	✓
hooks-HASH.js gzip	622 B	622 B	✓
image-HASH.js gzip	4.47 kB	4.47 kB	✓
index-HASH.js gzip	256 B	256 B	✓
link-HASH.js gzip	1.91 kB	1.91 kB	✓
routerDirect..HASH.js gzip	314 B	314 B	✓
script-HASH.js gzip	375 B	375 B	✓
withRouter-HASH.js gzip	309 B	309 B	✓
85e02e95b279..7e3.css gzip	107 B	107 B	✓
Overall change	13.2 kB	13.2 kB	✓

Client Build Manifests

	vercel/next.js canary	javivelasco/next.js refactor/sandbox-cache	Change
_buildManifest.js gzip	458 B	458 B	✓
Overall change	458 B	458 B	✓

Rendered Page Sizes

	vercel/next.js canary	javivelasco/next.js refactor/sandbox-cache	Change
index.html gzip	531 B	531 B	✓
link.html gzip	545 B	545 B	✓
withRouter.html gzip	526 B	526 B	✓
Overall change	1.6 kB	1.6 kB	✓

Commit: 3bdac83