Pm2: --experimental-modules flag appears to be ignored

[Andrey-Bushman]

I saw similar issue here, but it is old and closed. Therefore I create new issue.

Here is the simple example. It shows the problem. Look its readme.md file, please. How can I solve the problem?

Thank you.

[Andrey-Bushman]

I found issue #3751 and tried to use esm module instead of --experimental-modules option. It works fine. I will use it now. But it is workaround. It would be nice if the --experimental-modules option worked too (in the example I pushed to GitHub above).

Thank you.

[sidvishnoi]

The --experimental-modules flag works with pm2, but it doesn't take "type": "module" from package.json into account.

Example code:

// foo.js
export const foo = "bar";

// index.js
import { foo } from './foo.js';
console.log(foo)

// package.json
{
  "type": "module"
}

Running with node directly:

$ node -v
v12.6.0
$ node --experimental-modules index.js
(node:11912) ExperimentalWarning: The ESM module loader is experimental.
bar

Running with pm2:

$ pm2 --version
3.5.1
$ pm2 start index.js --node-args="--experimental-modules"
$ pm2 logs index --raw --err

(node:9712) ExperimentalWarning: The ESM module loader is experimental.
E:\GitHub\pm2-test\index.js:1
import { foo } from './foo.js';
       ^

SyntaxError: Unexpected token {
    at Module._compile (internal/modules/cjs/loader.js:720:23)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:787:10)
    at Module.load (internal/modules/cjs/loader.js:643:32)
    at Proxy.Module._load (internal/modules/cjs/loader.js:556:12)
    at Object.<anonymous> (C:\Users\[REDACTED]]\v12.6.0\node_modules\pm2\lib\ProcessContainerFork.js:27:21)
    at Module._compile (internal/modules/cjs/loader.js:776:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:787:10)
    at Module.load (internal/modules/cjs/loader.js:643:32)
    at Function.Module._load (internal/modules/cjs/loader.js:556:12)
    at internal/modules/esm/translators.js:87:15

[Andrey-Bushman]

Thank you, @sidvishnoi. How can I solve it? I see node hasn't --type parameter.

[sidvishnoi]

How can I solve it?

No idea. I'm reporting to support this issue to be fixed.

I see node hasn't --type parameter

Yes, there isn't. It has to be fixed at pm2 level.

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.