elm-http-builder

Chainable functions for building HTTP requests and composable functions for handling responses.

Need help? Join the #http channel in the Elm Slack!

Thanks to @fredcy, @rileylark, and @etaque for the original discussion of the API

Example

In this example, we expect a successful response to be JSON array of strings, like:

["hello", "world", "this", "is", "the", "best", "json", "ever"]

and an error response might have a body which just includes text, such as the following for a 404 error:

Not Found.

We'll use HttpBuilder.jsonReader and a Json.Decode.Decoder to parse the successful response body and HttpBuilder.stringReader to accept a string body on error without trying to parse JSON.

import Task exposing (Task)
import Time
import HttpBuilder exposing (..)
import Json.Decode as Decode
import Json.Encode as Encode


itemsDecoder : Decode.Decoder (List String)
itemsDecoder =
  Decode.list Decode.string


itemEncoder : String -> Encode.Value
itemEncoder item =
  Encode.object
    [ ("item", Encode.string item) ]


addItem : String -> Task (HttpBuilder.Error String) (HttpBuilder.Response (List String))
addItem item =
  HttpBuilder.post "http://example.com/api/items"
    |> withJsonBody (itemEncoder item)
    |> withHeader "Content-Type" "application/json"
    |> withTimeout (10 * Time.second)
    |> withCredentials
    |> send (jsonReader itemsDecoder) stringReader

Contributing

I'm happy to receive any feedback and ideas for about additional features. Any input and pull requests are very welcome and encouraged. If you'd like to help or have ideas, get in touch with me at @luke_dot_js on Twitter or @luke in the elmlang Slack!