[Premium] Nodejs Typescript: cannot import with absolute path in Azure Function

[DaCao]

I have this Nodejs Typescript Azure function in local:

<root-directory>
├── README.md
├── dist
├── host.json
├── local.settings.json
├── node_modules
├── package-lock.json
├── package.json
├── sealworker
│   ├── constants
│   ├── errors
│   ├── function.json
│   ├── index.ts
│   ├── interfaces
│   ├── sample.dat
│   ├── services
│   │     ├── worker.ts
│   │     └── ...
│   └── utils
│         ├── machineInfo.ts
│         └── ...
└── tsconfig.json

This is the tsconfig.json:

{
  "compilerOptions": {
    "module": "commonjs",
    "moduleResolution": "node",
    "target": "es6",
    "outDir": "dist",
    "rootDir": ".",
    "sourceMap": true,
    "strict": false,
    "esModuleInterop": true,
    "preserveConstEnums": true,
    "skipLibCheck": true,
    "forceConsistentCasingInFileNames": true,
    "baseUrl": "./sealworker",
    "paths": {
      "*": [
        "*",
        "sealworker/*",
        "node_modules/*"
      ]
    }
  },
  "exclude": [
    "node_modules",
    "**/*.test.ts"
  ],
  "include": [
    "**/*"
  ]
}

package.json:

{
  "name": "azure_function",
  "version": "1.0.0",
  "description": "",
  "scripts": {
    "build": "tsc",
    "watch": "tsc -w",
    "clean": "rimraf dist",
    "prestart": "npm run clean && npm run build",
    "start": "func start",
    "test": "echo \"No tests yet...\""
  },

   ...

This is the index.ts, which imports a function from ./services/worker.ts:

import { AzureFunction, Context, HttpRequest } from "@azure/functions";
import { workerExec } from "./services/worker";

const sealWorkerFunction: AzureFunction = async function (
  context: Context,
  req: HttpRequest
): Promise<void> {

...

and this is the ./services/worker.ts:

import "dotenv/config";
import "reflect-metadata";
import { HttpRequest, Context } from "@azure/functions";
import { getMachineInfo } from "utils/machineInfo";

export const workerExec = async (req: HttpRequest, context: Context) => {
  context.log("start....");

And this is utils/machineInfo.ts:

import os from "os";

// Get the machine info that identifies the current host running this code;
export const getMachineInfo = () => {
  const machineInfo = {
    // The machine's hostname;
    hostname: os.hostname(),
    // The machine's OS type;
    os: os.type(),
    // The machine's OS release;
    release: os.release(),
    // The machine's OS platform;
    platform: os.platform(),
    // The machine's OS architecture;
    arch: os.arch(),
    // The machine's OS uptime;
    uptime: os.uptime(),
    // The machine's total memory in MegaBytes;
    totalMemOfContainerInMB: os.totalmem() / 1024 / 1024,
    // the machine's number of CPUs;
    numCPUs: os.cpus().length,
  };
  return machineInfo;
};

Now it is complaining that the in line:

import { getMachineInfo } from "utils/machineInfo";

it cannot find module 'utils/machineInfo':

Error message:

[2023-08-10T03:59:00.616Z] Worker was unable to load entry point "dist/sealworker/index.js": Cannot find module 'utils/machineInfo'
[2023-08-10T03:59:00.616Z] Require stack:
[2023-08-10T03:59:00.616Z] - /Users/code/seal/azure_function/dist/sealworker/services/worker.js
[2023-08-10T03:59:00.616Z] - /Users/code/seal/azure_function/dist/sealworker/index.js
[2023-08-10T03:59:00.616Z] - /usr/local/Cellar/azure-functions-core-tools@4/4.0.5198/workers/node/dist/src/worker-bundle.js
[2023-08-10T03:59:00.616Z] - /usr/local/Cellar/azure-functions-core-tools@4/4.0.5198/workers/node/dist/src/nodejsWorker.js

I have tried different things with "baseUrl" and "paths" in tsconfig.json, and the values should be straight-forward and self explanatory now. But apparently I have made a mistake somewhere....

Any suggestions?

To Reproduce

I have made a public minimal reproducible repo at: https://github.com/DaCao/minimal_reproducible_example

To reproduce, git clone this repo and open VS Code:

1. You need to have Azure tools plugin installed in VS Code;

2. In local WORKSPACE, click the azure functions icon and choose:

3. Go through the creation process; select Programming Model V3;

4. After setting up the local project, build the nodejs:

john@MacBook-Pro:~/myapp/code/minimal_reproducible_example$ ls
host.json            local.settings.json  node_modules/        package-lock.json    package.json         sealworker/          tsconfig.json
john@MacBook-Pro:~/myapp/code/minimal_reproducible_example$ npm run-script build

> [email protected] build /Users/john/myapp/code/minimal_reproducible_example
> tsc

john@MacBook-Pro:~/myapp/code/minimal_reproducible_example$ 

you also need to have Azure Function Core Tools installed:

john@MacBook-Pro:~/myapp/code/minimal_reproducible_example$ func -v 
4.0.5198

and then just run:

john@MacBook-Pro:~/myapp/code/minimal_reproducible_example$ func start

you should see the error:

...

For detailed output, run func with --verbose flag.
[2023-08-11T05:38:06.464Z] Worker process started and initialized.
[2023-08-11T05:38:06.474Z] Worker was unable to load function sealworker: 'Cannot find module 'services/JobProcessor'
[2023-08-11T05:38:06.474Z] Require stack:
[2023-08-11T05:38:06.474Z] - /Users/john/myapp/code/minimal_reproducible_example/dist/sealworker/services/worker.js
[2023-08-11T05:38:06.474Z] - /Users/john/myapp/code/minimal_reproducible_example/dist/sealworker/index.js
[2023-08-11T05:38:06.474Z] - /usr/local/Cellar/azure-functions-core-tools@4/4.0.5198/workers/node/dist/src/worker-bundle.js
[2023-08-11T05:38:06.474Z] - /usr/local/Cellar/azure-functions-core-tools@4/4.0.5198/workers/node/dist/src/nodejsWorker.js'

...