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I have a typescript project where I get the ERROR_MODULE_NOT_FOUND 'path/to/compiled/file' when I try to run my compiled app.js file with node. However, I get rid of this error if I add a .js extension to the import statement in my app.js like this import { function } from "./path/file.js"; How do I get the typescript compiler to automatically add these .js extensions? Alternatively, get node to work without the .js extensions?

My tsconfig.json looks like this:

{
    "compilerOptions": {
        "module": "esnext",
        "target": "es5",
        "noImplicitReturns": true,
        "noUnusedLocals": true,
        "outDir": "dist",
        "sourceMap": true,
        "moduleResolution": "node",
        "esModuleInterop": true,
        "isolatedModules": true,
        "resolveJsonModule": true,
        "typeRoots": ["./src/types", "node_modules/@types"],
        "baseUrl": "./src",
        "paths": {
            "types": ["types"],
            "types/*": ["types/*"],
            "@data/*": ["data/*"],
            "@execute/*": ["execute/*"],
            "@indicators/*": ["indicators/*"],
            "@services/*": ["services/*"],
            "@strategies/*": ["strategies/*"],
            "*": ["node_modules/*"]
        }
    },
    "compileOnSave": true,
    "include": ["src", "test", "dist"],
    "exlude": ["src/types"]
}

My app.ts looks like this:

import { function } from "./path/file";

function();
console.log("test");

export {};
Victor Gunnarsson
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  • Are there multiple files with the same base name in the directory the module is in? Are you putting `.js` for the modules in the typescript file? – Nico Nekoru Apr 08 '21 at 20:03
  • Thank you for your comment! I have edited my post including the app.ts code. I am not using an extension inside my typescript file. Furthermore, there are two files with the same base name in the module: api.js and api.js.map, both of them are created by the compiler. – Victor Gunnarsson Apr 08 '21 at 20:08
  • The issue without the extension is probably due to ambiguity of which file to import from since there are multiple files it can do so from. I also assume that ts will compile with extension if extension is added to the ts file – Nico Nekoru Apr 08 '21 at 20:11
  • If I add a .js extension in the typescript file I get unable to resolve path, if I remove the api.js.map file it still doesn't work... – Victor Gunnarsson Apr 08 '21 at 20:16
  • Does https://stackoverflow.com/questions/55251956/how-does-javascript-import-find-the-module-without-an-extension answer your question? – Nico Nekoru Apr 08 '21 at 20:21
  • The way this thread describes the behavior doesn't seem to apply to my project as the node doesn't seem to automatically add a .js extension – Victor Gunnarsson Apr 08 '21 at 20:28

3 Answers3

2

I was having the exact same issue while trying to setup a new typescript project on node.

What solved it for me at the end was replacing esnext by commonjs on the module option.

I had previously used esnext because of a top-level await, but worked that around by wrapping the await with an async function.

I cannot explain why the compiled javascript imports with esnext does not have the .js extension, or how to tweak the compiler to add this extension for local modules that will also be compiled.

Guilherme Dellagustin
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1

I have got the same error. The ending ".js" in the typescript project looks weird, but without it does not work when I tried to start the app like that:

"start": "node ."

If you add --experimental-specifier-resolution=node then it will work. I am not sure whether it is a good practice to add something "experimental" to the app, but you can use it as a temporary solution.

"start": "node --experimental-specifier-resolution=node ."

Also, the node v18 is warning you: ExperimentalWarning:

The Node.js specifier resolution flag is experimental. It could change or be removed at any time

nobody
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0

When using ESNext, you need to specify full path with the extension.

John
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