[BUG] Source map generation - file not found warning

[jbpenrath]

Before you begin...

• I have searched the existing issues
• I am not using version 13.x of node (if so, please upgrade)

Description of the problem

Since the version 11.0.x, I get warnings related to uuid when generating source map at build. To build my project I'm using webpack so the package source-map-loader is used to generate source maps.

Here it is an example of warning I got :

WARNING in ./node_modules/uuid/dist/esm-browser/v6ToV1.js
Module Warning (from ./node_modules/source-map-loader/dist/cjs.js):
Failed to parse source map from '/Users/jbpenrath/dev/github/openfun/richie/src/frontend/node_modules/uuid/src/v6ToV1.ts' file: Error: ENOENT: no such file or directory, open '/Users/jbpenrath/dev/github/openfun/richie/src/frontend/node_modules/uuid/src/v6ToV1.ts'
 @ ./node_modules/uuid/dist/esm-browser/index.js 11:0-48 11:0-48
 @ ./js/widgets/LtiConsumer/index.tsx 24:0-36 51:19-25
 @ ./js/widgets/index.tsx 46:9-38
 @ ./js/index.tsx 48:0-31 183:42-46

It seems source-map-loader is looking for some files located in the src folder but this directory is not embedded in the package so the type file is not found.

I wonder if this is not related to the inlineSourceMap option enabled in your tsconfig.

Recipe for reproducing

No response

Additional information

No response

Environment

No response

[broofa]

There's something weird with your project configuration. That error is complaining about a missing uuid source file in node_modules directory ("...node_modules/uuid/src/v6ToV1.ts").

uuid doesn't install any src/* files.

You need to actually install uuid to get source maps (which are provided inline in the dist/* files).

[jbpenrath]

Actually, as src folder is not embedded in the released package, source-map-loader is not able to consume properly the sourceMappingUrl attribute included in uuid built files.

To fix the issue, there are two ways IMO :

1. uuid embeds src folder in the release (like mswjs/interceptors did for example)
2. We must tweak your webpack config to tell source-map-loader to skip source map from uuid package.

[broofa]

Sorry, apparently I misunderstood. Reopening for continued discussion.

The error message "Failed to parse source map from '...uuid/src/v6ToV1.ts'" sounds like it's trying to read a source map from a non-existent file. Are you saying the error instead stems from not being able to find a file referenced by the source map info?

If so, then the issue here is that this module ships with source maps (inline), but no source... which I agree is a bug. This means there's one of two options:

1. Include source files
2. Remove sourcemaps

I'm inclined to go with the latter because, historically, this project has not included sourcemaps and I don't recall anyone ever asking for them. And in looking through node_modules for one of the larger projects I have access to I only see sourcemaps in 489 of the 2013 modules (24%). So inclusion of sourcemaps appears to be the exception rather than the rule for NPM modules.

Also, this module doesn't call into user-code anywhere, so it's rare that callers would need to step into / debug it's runtime behavior.

That uuid@11 includes sourcemaps was a bit of an afterthought on my part, and not well-thought out. There was no request for them, nor was there any meaninful discussion about it. Removing them would be easy, and would reduce the package size somewhat.

So, question: Where this specific issue is concerned, would removing sourcemaps solve your problem? I.e. would it avoid the code path in question that's throwing this error? Or do you actually need uuid's sourcemap data? If so, why?

[vitaliyhan]

same

[jbpenrath]

IMO this is fine to remove sourcemap for now to prevent many questions about this warning and to keep the package size low.

Then you will have to think about source map feature only when someone really needs it.

[andrewstec]

I landed here because I started getting warnings about a source map being excluded:

WARNING in ../.yarn/cache/uuid-npm-11.0.2-13e156cc62-b98082f398.zip/node_modules/uuid/dist/cjs/v35.js
Module Warning (from ../.yarn/__virtual__/source-map-loader-virtual-33b8eec268/0/cache/source-map-loader-npm-5.0.0-62d48efeee-9bc90a50df.zip/node_modules/source-map-loader/dist/cjs.js):
Failed to parse source map from '/Users/spaghetti/repos/food/project/.yarn/cache/uuid-npm-11.0.2-13e156cc62-b98082f398.zip/node_modules/uuid/src/v35.ts' file: Error: ENOENT: no such file or directory, open '/node_modules/uuid/src/v35.ts'
 @ ../.yarn/cache/uuid-npm-11.0.2-13e156cc62-b98082f398.zip/node_modules/uuid/dist/cjs/v3.js 5:17-36 6:15-34
 @ ../.yarn/cache/uuid-npm-11.0.2-13e156cc62-b98082f398.zip/node_modules/uuid/dist/cjs/index.js 16:14-32
 @ ./src/services/bananaService.ts 22:15-30
 @ ./src/routes/exerciseRoutes.ts 13:26-64
 @ ./src/customRoutes.ts 19:41-75
 @ ./src/server.ts 10:23-48

Is it possible that there is a further convention to remove source maps without it triggering warnings? I am not opinionated on this issue, but you might get a lot of traffic about this issue. I'm not sure why or if it should occur. Webpack's source-map-loader could be too opinionated?

[joshkel]

@andrewstec The errors were because uuid v11.0.0 through 11.0.2 were built with source maps enabled, and so they distributed JS files that referenced external source maps via //# sourceMappingURL comment directives, but, to save space, they omitted the source maps themselves. That's why source-map-loader et al. were raising warnings.

Starting with 11.0.3, source maps are disabled, so no more warnings should be logged.

[andrewstec]

Thanks! I understand now. Much appreciated!

[broofa]

via //# sourceMappingURL comment directives, but, to save space, they omitted the source maps themselves

To be clear, 11.0.0-11.0.2 had inline source maps. So the issue wasn't that the source maps were missing, it was that the source files- the src/*.ts files - referenced by those source maps were never included... which renders the sourcemaps moot.

Either way, removing the sourcemaps should fix the problem. And 11.0.3 is out now, so this is mostly just me looking for an excuse to post memes of apes #PickingNits.