vercel: @now/node: Cannot find module '~' when using paths in TypeScript

Trying to use the micro-cookie-session lib with @now/node @canary and I’m getting this error below.

Don’t have the error when I run the code locally (with micro-dev)

Unable to import module 'launcher': Error
    at Function.Module._resolveFilename (module.js:547:15)
    at Function.Module._load (module.js:474:25)
    at Module.require (module.js:596:17)
    at require (internal/module.js:11:18)
    at Object.901 (/var/task/user/backend/index.js:4546:18)
    at __webpack_require__ (/var/task/user/backend/index.js:22:30)
    at Object.68 (/var/task/user/backend/index.js:69:18)
    at __webpack_require__ (/var/task/user/backend/index.js:22:30)
    at Object.262 (/var/task/user/backend/index.js:401:17)
    at __webpack_require__ (/var/task/user/backend/index.js:22:30)

edit: This happens in @now/node now.

For context, using typescript

About this issue

Original URL
State: open
Created 5 years ago
Reactions: 14
Comments: 27 (5 by maintainers)

Most upvoted comments

Any updates on this? My serverless function in api/ directory uses imports alias and I’m trying to find a way to make it work on vercel. Is there any way to achieve this at the moment?

emzet93 on Apr 25, 2022

Any follow-up here? Any suggestions on how to use Vercel withcustom paths?

neoromantic on Aug 20, 2021

On the docs https://zeit.co/docs/runtimes#official-runtimes/node-js/using-typescript-with-the-node-js-runtime:

Most options are supported aside from “Path Mappings” and “Project References”.

Is this the right issue to track where these two features are going to be supported by now?

amaury1093 on Nov 17, 2019

I think we originally thought this was a ncc bug with broken typescript paths.

But I confirmed it works fine with ncc 🤔

The canary builder has improved error messages so I went ahead and deployed zeit-now-typescript-broken-example and I see the error Cannot find module '~app'. So it looks like this is a bug with the builder, but it requires further investigation.

styfle on Mar 26, 2019

Yup just spent 1h this afternoon trying to figure this out.

I think setting "paths" in TS is common enough to have well documented this incompatibility and possible workarounds. I’m happy to contribute with documentation PRs 🙌🏼

ubbe-xyz on Jul 2, 2020

@styfle just following up on this bug, since it’s still blocking us from using TS in production with Zeit. Can you let me know if you were able to reproduce the above behavior with my repository?

liamdanielduffy on May 20, 2019

I’ve got the same error with typescript when I’m trying to use custom imports (paths or baseUrl in tsconfig.json)

Reporoduction Example repo - https://github.com/pie6k/zeit-now-typescript-broken-example/

pie6k on Feb 25, 2019

vercel dev still has this problem. I checked the code in dev-server.js, it seems that ts-node only uses target in provided tsconfig.json.

gaoxiaoliangz on Aug 9, 2020

So is there any workaround? If not - then now should throw an error is paths in tsconfig are not empty.

theKashey on Jun 1, 2020

I have the same error message since yesterday (21 Mar) (Unable to import module 'launcher': Error...)

I can build and run locally with ncc but once deployed to Now I get this error message. My repo worked fine for the last several weeks, it’s only since yesterday I’m getting this error.

UPDATE:

I’ve set "use": "@now/node@canary" in my now.json config to try to track down the bug, but it’s no longer necessary, the deployment runs without any errors with this setting! 💯

(note: I didn’t even know that the @canary suffix existed before…)

bfulop on Mar 28, 2019

Hate to say bump, but this hasnt gotten any visiblity, and i have absolutely no way to debug this.

cryptiklemur on Mar 23, 2019