CommonJS dependencies crash SSR server

[rtsao]

Describe the bug

CommonJS dependencies encountered during SSR can crash the server (e.g. ReferenceError: module is not defined or ReferenceError: require is not defined, depending on which is first) if workspaces are used in some capacity.

I have identified two specific scenarios where this will occur:

1. The CJS dependency is a workspace (i.e. app → cjs-workspace)
2. The CJS dependency is a sub-dependency of a pnpm or Yarn PnP workspace dependency (i.e. app → other-workspace → cjs-npm-dependency)

While possibly confusing, the first scenario is arguably intentional behavior because workspaces are typically implemented with symlinks and this logic indicates that symlinked packages should never be externalized:

vite/packages/vite/src/node/plugins/resolve.ts

Lines 656 to 659 in c6870f3

	// don't external symlink packages
	if (!allowLinkedExternal && !resolved.id.includes('node_modules')) {
	return resolved
	}

However, the second scenario is almost certainly a bug.

Reproduction

https://github.com/rtsao/vite-bug-repro-cjs-workspaces (for scenario 1)
https://github.com/rtsao/vite-bug-repro-ssr-pnp and https://github.com/rtsao/vite-bug-repro-ssr-pnpm (for scenario 2)

System Info

System:
    OS: macOS 12.5
    CPU: (10) arm64 Apple M1 Max
    Memory: 36.02 GB / 64.00 GB
    Shell: 5.8.1 - /bin/zsh
  Binaries:
    Node: 16.16.0 - ~/Library/Caches/fnm_multishells/1157_1660588473591/bin/node
    Yarn: 3.2.2 - ~/Library/Caches/fnm_multishells/1157_1660588473591/bin/yarn
    npm: 8.11.0 - ~/Library/Caches/fnm_multishells/1157_1660588473591/bin/npm
  Browsers:
    Chrome: 104.0.5112.101
    Safari: 15.6

Used Package Manager

yarn

Logs

Click to expand!

vite-bug-repro-ssr-pnp main
❯ corepack enable
yarn install
yarn node app/server.mjs
➤ YN0000: ┌ Resolution step
➤ YN0000: └ Completed
➤ YN0000: ┌ Fetch step
➤ YN0013: │ vite@npm:3.0.8 can't be found in the cache and will be fetched from the remote registry
➤ YN0013: │ which@npm:2.0.2 can't be found in the cache and will be fetched from the remote registry
➤ YN0013: │ wide-align@npm:1.1.5 can't be found in the cache and will be fetched from the remote registry
➤ YN0013: │ wrappy@npm:1.0.2 can't be found in the cache and will be fetched from the remote registry
➤ YN0013: │ yallist@npm:4.0.0 can't be found in the cache and will be fetched from the remote registry
➤ YN0000: └ Completed
➤ YN0000: ┌ Link step
➤ YN0000: │ ESM support for PnP uses the experimental loader API and is therefore experimental
➤ YN0007: │ esbuild@npm:0.14.54 must be built because it never has been before or the last one failed
➤ YN0000: └ Completed in 0s 616ms
➤ YN0000: Done with warnings in 0s 788ms
http://localhost:5173
ReferenceError: module is not defined
    at /@fs/Users/rtsao/code/vite-bug-repro-ssr-pnp/.yarn/cache/locale-npm-0.1.0-6c7fdc5891-42af4432bc.zip/node_modules/locale/lib/index.js:159:3
    at /@fs/Users/rtsao/code/vite-bug-repro-ssr-pnp/.yarn/cache/locale-npm-0.1.0-6c7fdc5891-42af4432bc.zip/node_modules/locale/lib/index.js:161:4
    at instantiateModule (file:///Users/rtsao/code/vite-bug-repro-ssr-pnp/.yarn/__virtual__/vite-virtual-f00fbd239e/0/cache/vite-npm-3.0.8-cf480b5a77-ec3f57d52f.zip/node_modules/vite/dist/node/chunks/dep-74663fff.js:50512:15)
ReferenceError: module is not defined
    at /@fs/Users/rtsao/code/vite-bug-repro-ssr-pnp/.yarn/cache/locale-npm-0.1.0-6c7fdc5891-42af4432bc.zip/node_modules/locale/lib/index.js:157:3
    at /@fs/Users/rtsao/code/vite-bug-repro-ssr-pnp/.yarn/cache/locale-npm-0.1.0-6c7fdc5891-42af4432bc.zip/node_modules/locale/lib/index.js:159:4
    at instantiateModule (file:///Users/rtsao/code/vite-bug-repro-ssr-pnp/.yarn/__virtual__/vite-virtual-f00fbd239e/0/cache/vite-npm-3.0.8-cf480b5a77-ec3f57d52f.zip/node_modules/vite/dist/node/chunks/dep-74663fff.js:50512:15)

Validations

• Follow our Code of Conduct
• Read the Contributing Guidelines.
• Read the docs.
• Check that there isn't already an issue that reports the same bug to avoid creating a duplicate.
• Make sure this is a Vite issue and not a framework-specific issue. For example, if it's a Vue SFC related bug, it should likely be reported to vuejs/core instead.
• Check that this is a concrete bug. For Q&A open a GitHub Discussion or join our Discord Chat Server.
• The provided reproduction is a minimal reproducible example of the bug.

[sun0day]

It seems like Vite has not supported ssr pre bundle yet. See https://github.com/vitejs/vite/blob/main/packages/vite/src/node/optimizer/optimizer.ts#L724

[patak-dev]

There is now support for prebundling SSR deps during dev, which should give a way out of these issues. You need to manually enable it, and add these dependencies to the include list:

ssr: {
  optimizeDeps: {
    disabled: 'build'
    include: [ 'dep' ]
  }
}

[sun0day]

It didn't work, did I miss something? @patak-dev

There is now support for prebundling SSR deps during dev, which should give a way out of these issues. You need to manually enable it, and add these dependencies to the include list:

ssr: {
  optimizeDeps: {
    disabled: 'build'
    include: [ 'dep' ]
  }
}

[patak-dev]

Just in case @sun0day, 'dep' was a placeholder, did you replace that with the dependency you want to optimize? Please share a minimal reproduction of your setup if that is the case

[sun0day]

Just in case @sun0day, 'dep' was a placeholder, did you replace that with the dependency you want to optimize? Please share a minimal reproduction of your setup if that is the case

I just clone https://github.com/rtsao/vite-bug-repro-ssr-pnp mentioned above, and add

ssr: {
    optimizeDeps: {
      disabled: 'build',
      include: [ 'pkg-a' ]
    }
  }

to app/vite.config.js. Then follow the reproduction steps as README.md says.

[rtsao]

I'm aware of a workaround to forcibly externalize these deps (as they should be): {ssr: {external: ["the-dep"]}}) but this is rather cumbersome for large projects where there could be hundreds of CommonJS sub-dependencies. Very few npm packages are ESM.

I think the heuristics for whether dependencies should be externalized is broken somehow.

There is now support for prebundling SSR deps during dev

Why bundle server dependencies? Isn't this just overhead?

[rtsao]

Put together a fix: #9763

TL;DR: the current externalization method of attempting to resolve all nested deps from root is broken with pnpm and Yarn PnP

[arthurgailes]

@rtsao Thank you. This also appears to affect nx workspaces, in my case with the package d3.

[arthurgailes]

I'm aware of a workaround to forcibly externalize these deps (as they should be): {ssr: {external: ["the-dep"]}}) but this is rather cumbersome for large projects where there could be hundreds of CommonJS sub-dependencies. Very few npm packages are ESM.

I think the heuristics for whether dependencies should be externalized is broken somehow.

There is now support for prebundling SSR deps during dev

Why bundle server dependencies? Isn't this just overhead?

Thank you, this actually worked for me as {ssr: {noExternal: ["the-dep"]}}

Overall, it took several hours to track down the cause here - thank you for your PR on the subject.

[edikdeisling]

Run into this issue. I have case 2 with pnpm: workspace-package-1 -> workspace-package-2 -> jsdom.
Adding {ssr: {noExternal: ["jsdom"]}} or {ssr: {optimizeDeps: {disabled: 'build', include: [ 'jsdom' ]}}} doesn't help.

But for some reason adding jsdom as a dependency for workspace-package-1 helped. So for now I added all these broken dependencies to both workspace packages

[rtsao]

This is still a bug as of vite@4.2.1:

• pnpm: https://github.com/rtsao/vite-bug-repro-ssr-pnpm
• Yarn: https://github.com/rtsao/vite-bug-repro-ssr-pnp

[rtsao]

I've rebased the fix for this issue: #9763 and is passing CI again

[vincenteof]

There is now support for prebundling SSR deps during dev, which should give a way out of these issues. You need to manually enable it, and add these dependencies to the include list:

ssr: {
  optimizeDeps: {
    disabled: 'build'
    include: [ 'dep' ]
  }
}

I add this config for @prisma/client and the resolution works fine, but seems that prisma is using __dirname in its source, and error says __dirname is not defined, what can I do?