Cannot find module "protobuf/minimal", "Did you mean to import protobufjs/minimal.js?"

[birgersp]

protobuf.js version: 7.2.0

Trying to use protobufjs in an ES module.

{
	"name": "myproject",
	"version": "1.0.0",
	"type": "module",
	"dependencies": {
		"protobufjs": "^7.2.0"
	},
	"devDependencies": {
		"protobufjs-cli": "^1.1.0",
		"typescript": "^4.9.5"
	}
}

I generated the protobuf messages module (and typings) like this

npx pbjs -t static-module -w es6 protobuf/myproject.proto -o src/protobuf/protobuf.js
npx pbts src/protobuf/protobuf.js -o src/protobuf/protobuf.d.ts

At the top of the src/protobuf/protobuf.js file I see this:

/*eslint-disable block-scoped-var, id-length, no-control-regex, no-magic-numbers, no-prototype-builtins, no-redeclare, no-shadow, no-var, sort-vars*/
import * as $protobuf from "protobufjs/minimal";

Given a simple program

// src/main.ts
import { SomeMessage } from "src/protobuf.js"
console.log("Hello world!")

And compiling with this tsconfig.json:

{
	"compilerOptions": {
		"module": "NodeNext",
		"moduleResolution": "nodenext",
		"target": "ES2022",
		"sourceMap": true,
		"strict": true,
		"skipLibCheck": true,
		"outDir": "build",
		"noImplicitAny": false,
		"allowJs": true
	},
	"include": [
		"src/**/*",
		"tests/**/*"
	]
}

When I try to run the project node --enable-source-maps build/main.js I get this error message:

Error [ERR_MODULE_NOT_FOUND]: Cannot find module '/home/birger/myproject/node_modules/protobufjs/minimal' imported from /home/birger/myproject/build/src/protobuf/protobuf.js
Did you mean to import protobufjs/minimal.js?

Tbh I don't know if I correctly understood the process of generating the protobuf module with typings. Should I not be using the -w es6 flag?

[ygrandgirard]

I think there are actually two separate issues with this import line:

• it is missing the .js extension, it should be protobufjs/minimal.js,
• the generated code expects the default import to be directly accessible, which is not what import * as does.

---

The README.md for protobufjs-cli is outdated and pbjs actually has a --dependency flag. As per pbjs --help:

--dependency     Specifies which version of protobuf to require. Accepts any valid module id

So adding --dependency protobufjs/minimal.js to your command should fix the first issue.
‎
To solve the second issue, I ended up creating my own wrapper.js file instead of using the built-in es6 one:

import $protobuf from $DEPENDENCY;

$OUTPUT;

export default $root;

---

Puttng it all together, in your case the final command would look something like this:

npx pbjs -t static-module -w path/to/wrapper.js --dependency protobufjs/minimal.js --es6 protobuf/myproject.proto -o src/protobuf/protobuf.js

‎
That should work, at least it does for me. But I think this should be supported out of the box.

[antonio-ivanovski]

Agree with @ygrandgirard, and thanks for the workaround.

Was facing the same issues, but was thinking of writing my own post-processing script. The team should fix this.

[RadiatedExodus]

It has been 1 year since this issue was made, I have had a lot of time wrecking my head to figure out why pbjs won't generate code that works with esm for months. This REALLY needs to be fixed. I've spent hours googling around to find nearly no information how to solve this.

The workaround above was the final piece to fix my issues.... Thank you.

[alexlawrence]

Thanks for the workaround @ygrandgirard! Same as @RealEthanPlayzDev, I spent hours trying to figure out what is wrong :(

[taclayto52]

@ygrandgirard thank you very much for the workaround!
Wish this issue would get fixed sooner than later. I also spent hours thinking there was some issue with my tsconfig.

[luisasc]

@ygrandgirard thanks for your workaround, it looks really promising!
I've tried to implement it in an Angular 19 App, and I'm getting these error logs that I'm not quite sure how to address:
`
[error] src/types/protobuf/wrapper.js: SyntaxError: Unexpected token (1:23)
[error] > 1 | import $protobuf from $DEPENDENCY;
[error] | ^
[error] 2 |
[error] 3 | $OUTPUT;
[error] 4 |

`

my command to generate the files is this:
pbjs --es6 --target static-module --wrap src/types/protobuf/wrapper.js --dependency protobufjs/minimal.js --out src/types/protobuf/testing.js protobuf/Testing.proto && pbts --out src/types/protobuf/testing.d.ts src/types/protobuf/testing.js

has anyone seen this before?