How to create a custom helper?

[melokki]

Hello
I am trying to create a custom helper, but I can't figure out how to do it
I've created a new folder helpers where I've placed my code
But when I run my code to helper is not available and I get the following error

Cannot find module 'helpers/listToTree'

in .adonisrc.json file at preloads key I have the following

"preloads": [
    "./start/routes",
    "./start/kernel",
    "./helpers/listToTree"
  ],

Any suggestion?

[RomainLanz]

Hey @melokki! 👋🏻

It seems like an XY Problem.
What are you trying to achieve (removing the fact that loading your file is not working)?

[melokki]

Hello, thank you for your reply :)

I am trying to create a helper function that transforms a flat array into a tree. I might need this function in other parts of the application and I thought that making this function as a helper would be a good idea.

[RomainLanz]

Yeah, but why are you trying to preload the file?

Create a simple JS file anywhere you want (like in App/Helpers), and import it like in any JS codebase.

import myHelpers from 'App/Helpers'

// ...

[melokki]

I tried that and it didn't work, I got the same error and I thought maybe I need to preload it or something. Will give it a try again maybe I did something wrong. thank you very much for your time :)

[melokki]

I managed to make it working after I did the following:

In the root folder of the application I've created a new folder called helpers

in .adonisrc.json file I added this line:

"aliases": {
   ...
    "Helpers": "helpers"
  },

and in tsconfig.json I've added the following:

"compilerOptions": {
    "outDir": "build",
    "rootDir": "./",
    "sourceMap": true,
    "paths": {
      ...
      "Helpers/*": [
        "./helpers/*"
      ]
    },

Now I can make the import from Helpers and the code works just fine.
I don't know if it's the right way

[AbidKhairyAK]

for adonisjs v6, instead of writing alias in .adonisrc.json file, you need to write subpath alias in your package.json

[backend-sempoa]

can you guys implement this in command file? @melokki

[gregmsanderson]

Yep, a node ace make:helper name.

I was looking how to add a nanoid. Closest is https://docs.adonisjs.com/guides/references/helpers#cuid but it could be nice to add to those provided helpers in an "offficial" way