How to get object argument from npm script (NodeJS + TypeScript)

I want to pass an object via NPM script like

  "update-user-roles": "ts-node user-roles.ts {PAID_USER: true, VIP: true}"

My function picks up the object but keeps adding additional commas so it's not updating the user correctly. How do I receive the object as is?

async function updateUserRoles(roles: any) {
    const userID = await getAuth().then((res) => res.uid);
    updateUser({
        userID: userID,
        fields: {
            roles: {
                roles
            },
        }
    })
    console.log(`User roles successfully added: ${roles}`)
}

const rolesString = JSON.stringify(process.argv.slice(2))
updateUserRoles(JSON.parse(rolesString))

I get the following message:

User roles successfully added: {PAID_USER:,true,,VIP:,true}

The reason why you got comma , is because Nodejs will split command-line arguments at whitespace. The process.argv array will be like this:

[
  '/home/lindu/workspace/project/node_modules/.bin/ts-node',
  '/home/lindu/workspace/project/index.ts',
  '{PAID_USER:',
  'true,',
  'VIP:',
  'true}'
]

> The process.argv property returns an array containing the command-line arguments passed when the Node.js process was launched.

Option 1. Pass a JSON string

$ npx ts-node ./index.ts '{"PAID_USER": true, "VIP": true}'

index.ts

console.log(process.argv);
console.log(JSON.parse(process.argv.slice(2)[0]));

Output:

[
  '/home/lindu/workspace/project/node_modules/.bin/ts-node',
  '/home/lindu/workspace/project/index.ts',
  '{"PAID_USER": true, "VIP": true}'
]
{ PAID_USER: true, VIP: true }

Option 2. Pass a string and parse it to a JSON string.

npx ts-node ./index.ts '{PAID_USER: true, VIP: true}'

index.ts:

console.log(process.argv);

const arg = process.argv.slice(2)[0];
const obj = JSON.parse(JSON.stringify(eval('(' + arg + ')')));
console.log(obj, typeof obj, obj.PAID_USER, obj.VIP);

Output:

[
  '/home/lindu/workspace/project/node_modules/.bin/ts-node',
  '/home/lindu/workspace/project/index.ts',
  '{PAID_USER: true, VIP: true}'
]
{ PAID_USER: true, VIP: true } object true true

Option 3. Use minimistjs package.

We can use double quotes to wrap the object.

"update-user-roles": "ts-node user-roles.ts \"{\\\"PAID_USER\\\": true, \\\"VIP\\\": true}\""

After that:

async function updateUserRoles(rolesString: string) {
  const roles = JSON.parse(rolesString);
  const userID = await getAuth().then((res) => res.uid);
  updateUser({
    userID: userID,
    fields: {
      roles: roles
    }
  });
  console.log(`User roles successfully added: ${JSON.stringify(roles)}`);
}

It should work.

As you may have noticed, you are not passing in a real object as a parameter, but a string that is not a valid json.

First, the parameter must be wrapped and escaped (\"{...}\") so that it is not split up by the blanks.

Here then come two helper functions. One to read out the parameter using a key (myObject). And the second to make an object out of the string (fake json).

"update-user-roles": "ts-node user-roles.ts myObject=\"{PAID_USER: true, VIP: true}\""

And here is the minimal JavaScript functionality.

const args = process.argv.slice(2).reduce((acc, arg) => {
	let [k, v = true] = arg.split('=');
	acc[k] = v;
	return acc;
}, {});

console.log(args) // { myObject: '{PAID_USER: true, VIP: true}' }

const parseJSON = obj => Function('"use strict";return (' + obj + ')')();

const myObject = parseJSON(args.myObject); // { PAID_USER: true, VIP: true }

Your function call would then be

updateUserRoles(myObject);

I couldn't get any of these answers to work, finally got a solution using the following:

The script:

"ts-node user-roles.ts '{\"PAID_USER\": true, \"VIP\": true}'"

Parse the object string back into an object using JSON.parse and pass to function:

const objArgStr = process.argv[2];

if (!objArgStr) {
  console.error('No argument provided.');
  process.exit(1);
}

const objArg = JSON.parse(objArgStr);
console.log('Object argument: ', objArg);

updateUserRoles(objArg)

The problem is that Node.js treats arguments as string and splits them by whitespace, so roles looks something like this:

[
  "{PAID_USER:",
  "true,",
  "VIP:",
  "true}"
]

Also, it's not a JSON string. You have to turn that to JSON and wrap in quotes so Node.js will count the entire thing as one argument:

ts-node user-roles.ts "{\"PAID_USER\": true, \"VIP\": true}"

Don't forget to escape quotes in string!!

In user-roles.ts:

const rolesString = process.argv.slice(2)[0]
updateUserRoles(JSON.parse(rolesString))

Because process.argv.slice(2) returns an Array, you'll need to get the first argument. You also don't need JSON.stringify().
It can be simplified like this:

updateUserRoles(JSON.parse(process.argv.slice[2]))