elm-http-builder

Chainable functions for building HTTP requests

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import Http
import HttpBuilder exposing (..)
import Json.Decode as Decode
import Json.Encode as Encode

type Status a = Loading | Loaded a | Failure

type alias Model = { items : Status (List String) }

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


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


{-| addItem will send a post request to
`"http://example.com/api/items?hello=world"` with the given JSON body, a
custom header, and cookies included. It'll try to decode with `itemsDecoder`.

-}
addItem : String -> Cmd Msg
addItem item =
    HttpBuilder.post "http://example.com/api/items"
        |> withQueryParams [ ("hello", "world") ]
        |> withHeader "X-My-Header" "Some Header Value"
        |> withJsonBody (itemEncoder item)
        |> withTimeout 10000
        |> withExpectJson GotItem itemsDecoder
        |> withCredentials
        |> send

type Msg = GotItem (Result Http.Error (List String))

update : Msg -> Model -> ( Model, Cmd Msg )
update msg model =
    case msg of
        GotItem (Ok items) ->
          ( { model | items = Loaded items }
          , Cmd.none
          )

        GotItem (Err err) ->
          ( { model | items = Failure } , Cmd.none)