Accent

Installation

This package can be installed by adding accent to your list of dependencies in mix.exs:

def deps do
  [{:accent, "~> 0.2"}]
end

Please note that you will need to provide accent with a JSON codec. Both poison and jason are supported.

Usage

This project provides two plugs for handling the conversion of JSON keys to different cases: Accent.Plug.Request and Accent.Plug.Response

Accent.Plug.Request

Transforms the keys of an HTTP request's params to the same or a different case.

You can specify what case to convert keys to by passing in a :transformer option.

Accent supports the following transformers out of the box:

• Accent.Transformer.CamelCase (e.g. CamelCase)
• Accent.Transformer.PascalCase (e.g. pascalCase)
• Accent.Transformer.SnakeCase (e.g. snake_case)

If no transformer is provided then Accent.Transformer.SnakeCase will be used.

Please note that this plug will need to be executed after the request has been parsed.

Example

Given this request:

curl -X POST https://yourapi.com/endpoints \
  -H "Content-Type: application/json" \
  -d '{"helloWorld": "value"}'

a router with this configuration:

plug Plug.Parsers, parsers: [:urlencoded, :multipart, :json],
                   pass: ["*/*"],
                   json_decoder: Poison

plug Accent.Plug.Request

could expect to receive a conn.params value of:

%{"hello_world" => "value"}

Accent.Plug.Response

Transforms the keys of an HTTP response to the case requested by the client.

A client can request what case the keys are formatted in by passing the case as a header in the request. By default the header key is Accent. If the client does not request a case or requests an unsupported case then no conversion will happen. By default the supported cases are camel, pascal and snake.

Options

• :header - the HTTP header used to determine the case to convert the response body to before sending the response (default: Accent)
• :json_encoder - module used to encode JSON. The module is expected to define a encode!/1 function for encoding the response body as JSON. (required)
• :json_decoder - module used to decode JSON. The module is expected to define a decode!/1 function for decoding JSON into a map. (required)
• :supported_cases - map that defines what cases a client can request. By default camel, pascal and snake are supported.

Examples

Given this request:

curl -X POST https://yourapi.com/endpoints \
  -H "Content-Type: application/json" \
  -H "Accent: pascal" \
  -d '{"helloWorld": "value"}'

with this router:

defmodule MyAPI.Router do
  use Plug.Router

  plug Accent.Plug.Response, json_encoder: Poison,
                             json_decoder: Poison

  post "/endpoints" do
    send_resp(conn, 200, Poison.encode!(%{hello_world: "value"}))
  end
end

a client could expect a JSON response of:

{
  "helloWorld": "value"
}

Contributors

A special thanks to all of our contributors!

• @anthonator
• @maxsalven
• @szajbus