# ProperCase
An Elixir library that converts keys in maps between `snake_case` and `camel_case`.
Useful as a plug in Phoenix for converting incoming params from JavaScript's `camelCase` to Elixir's `snake_case`
Converts all keys in maps to snake case
`ProperCase.to_snake_case/1`
Converts all keys in maps to camel case
`ProperCase.to_camel_case/1`
Converts a string to snake case
`ProperCase.snake_case/1`
Converts a string to camel case
`ProperCase.camel_case/1`
### Example: `ProperCase.to_snake_case`
```elixir
# Before:
%{"user" => %{
"firstName" => "Han",
"lastName" => "Solo",
"alliesInCombat" => [
%{"name" => "Luke", "weaponOfChoice" => "lightsaber"},
%{"name" => "Chewie", "weaponOfChoice" => "bowcaster"},
%{"name" => "Leia", "weaponOfChoice" => "blaster"}
]
}
}
# After
%{"user" => %{
"first_name" => "Han",
"last_name" => "Solo",
"allies_in_combat" => [
%{"name" => "Luke", "weapon_of_choice" => "lightsaber"},
%{"name" => "Chewie", "weapon_of_choice" => "bowcaster"},
%{"name" => "Leia", "weapon_of_choice" => "blaster"}
]
}
}
```
# Using as a plug in Phoenix
`ProperCase` is extremely useful as a part of your connection pipeline, converting incoming params from
JavaScript's `camelCase` to Elixir's `snake_case`
Plug it into your `router.ex` connection pipeline like so:
```elixir
pipeline :api do
plug :accepts, ["json"]
plug ProperCase.Plug.SnakeCaseParams
end
```
## Installation
If [available in Hex](https://hex.pm/docs/publish), the package can be installed as:
1. Add proper_case to your list of dependencies in `mix.exs`:
def deps do
[{:proper_case, "~> 0.1.0"}]
end
2. Ensure proper_case is started before your application:
def application do
[applications: [:proper_case]]
end