ESM builds are unusable in NodeJS

[vladfrangu]

Expected behavior

Importing the module in an ESM-based project should not throw errors

Actual behavior

Importing the module in an ESM-based project throws errors related to missing file extensions.

❯ node test.mjs                                  
node:internal/errors:490
    ErrorCaptureStackTrace(err);
    ^

Error [ERR_MODULE_NOT_FOUND]: Cannot find module '/Users/vlad/Development/test/node_modules/web3/lib/esm/web3' imported from /Users/vlad/Development/test/node_modules/web3/lib/esm/index.js
    at new NodeError (node:internal/errors:399:5)
    at finalizeResolution (node:internal/modules/esm/resolve:326:11)
    at moduleResolve (node:internal/modules/esm/resolve:945:10)
    at defaultResolve (node:internal/modules/esm/resolve:1153:11)
    at nextResolve (node:internal/modules/esm/loader:163:28)
    at ESMLoader.resolve (node:internal/modules/esm/loader:838:30)
    at ESMLoader.getModuleJob (node:internal/modules/esm/loader:424:18)
    at ModuleWrap.<anonymous> (node:internal/modules/esm/module_job:77:40)
    at link (node:internal/modules/esm/module_job:76:36) {
  code: 'ERR_MODULE_NOT_FOUND'
}

Node.js v18.16.0

Running node with --experimental-specifier-resolution=node throws a separate error related to lack of import assertions on JSON files.

❯ node --experimental-specifier-resolution=node test.mjs 
(node:50994) ExperimentalWarning: The Node.js specifier resolution flag is experimental. It could change or be removed at any time.
(Use `node --trace-warnings ...` to show where the warning was created)
node:internal/errors:490
    ErrorCaptureStackTrace(err);
    ^

TypeError [ERR_IMPORT_ASSERTION_TYPE_MISSING]: Module "file:///Users/vlad/Development/test/node_modules/web3-eth-accounts/lib/esm/common/chains/goerli.json" needs an import assertion of type "json"
    at new NodeError (node:internal/errors:399:5)
    at validateAssertions (node:internal/modules/esm/assert:95:15)
    at defaultLoad (node:internal/modules/esm/load:84:3)
    at nextLoad (node:internal/modules/esm/loader:163:28)
    at ESMLoader.load (node:internal/modules/esm/loader:605:26)
    at ESMLoader.moduleProvider (node:internal/modules/esm/loader:457:22)
    at new ModuleJob (node:internal/modules/esm/module_job:64:26)
    at #createModuleJob (node:internal/modules/esm/loader:480:17)
    at ESMLoader.getModuleJob (node:internal/modules/esm/loader:434:34)
    at async ModuleWrap.<anonymous> (node:internal/modules/esm/module_job:79:21) {
  code: 'ERR_IMPORT_ASSERTION_TYPE_MISSING'
}

Node.js v18.16.0

Steps to reproduce the behavior

1. Install web3@4.0.1-rc.1
2. Create an mjs file (test.mjs)
3. Try the following code

import { Web3 } from 'web3';

const web3 = new Web3('http://localhost:8545');

Environment

• nodejs 18.16.0
• npm 9.5.1
• yarn 3.5.1
• web3 4.0.1-rc.1

[jdevcs]

@vladfrangu Thanks for testing RC, this issue is fixed under #6032 and another RC with fix will be released in this week.

[vladfrangu]

Awesome! Just one curiosity, does that also fix the missing .js extensions in files imported in ESM builds?

[luu-alex]

@vladfrangu what does the error output look like for missing .js extensions?

[vladfrangu]

See the first error sent in the issue report!

[jdevcs]

For

missing .js extensions in files imported in ESM builds?

there will still need of --experimental-specifier-resolution=node

[vladfrangu]

Ideally tho that shouldn't be needed! Not only because its experimental (so we don't know if it'll even remain in node, although it's likely it will remain), but because the fix is quite simple (which is just appending .js to every import statement, or using a bundler like tsup) 😅

[luu-alex]

Thanks @vladfrangu i'll be taking a look into getting rid of the experimental flag and seeing if I can get this out before release, if not it'll be apart of the next update.

[luu-alex]

@vladfrangu thank you so much for creating this issue and even providing me an idea on how to do it :) created a PR and hopefully will be merged soon after feedback.

[jdevcs]

#5994

[jdevcs]

Thanks @luu-alex