camelize-ts

A typescript typed snake_case function that recursively snake cases a camel cased object structure. It snake cases a simple string too, if you need that.

Why do this again?

This has obviously been done before, and the "new" thing with this pacakge is not snake casing itself but the fact that it is a generic that, given the form of the input data structure, will provide you with typing for the returned object structure so that it fits with other types.

As an example we've been using it to prepare data for requests to an API that expects snake cased parameter names while at the same time avoiding the snake case stuff from leaking into our React frontend.

Example

import snakify from 'snakify-ts'

// Expects snake case
function postIt({
  first_name,
  last_name
}: {
  id: number,
  first_name: string,
  last_name: string,
  roles: string[]
}) { return `${first_name} ${last_name}` }

// snake case stuff before posting to API
const snakifiedUser = snakify<{
  id: number;
  firstName: string;
  lastName: string;
  roles: string[];
}>({
  id: 1,
  firstName: 'Grim',
  lastName: 'Reaper',
  roles: ['user', 'admin']
})

console.log(JSON.stringify(snakifiedUser, null, 2))
console.log(postIt(snakifiedUser)

output:

{
  "id": 1,
  "first_name": "Grim",
  "last_name": "Reaper",
  "roles": [
    "user",
    "admin"
  ]
}

Grim Reaper

Running tests

npm run test // one time/CI
npm run test:watch // on each file change

Licence

MIT