so-34530326.elm

import Signal
import Http
import Task
import Effects
import Html exposing (..)
import Html.Events exposing (..)
import Json.Decode

type Action
  = NoOp
  | GetShortenedUrl
  | SetShortenedUrl (Maybe String)

type alias Model =
  { shortenedUrl : Maybe String }

init : (Model, Effects.Effects Action)
init =
  ({ shortenedUrl = Nothing }, Effects.none)

update : Action -> Model -> (Model, Effects.Effects Action)
update action model =
  case action of
    NoOp ->
      (model, Effects.none)
    GetShortenedUrl ->
      (model, shortenedUrlGetter)
    SetShortenedUrl val ->
      ({ model | shortenedUrl = val }, Effects.none)

shortenedUrlGetter =
  Http.post Json.Decode.string "./test.txt" body -- "http://localhost/tracker/link-admin/test.php" body 
    |> Task.toMaybe 
    |> Task.map SetShortenedUrl 
    |> Effects.task

body = Http.empty

---------------

messages =
  Signal.mailbox []

actions : Signal.Mailbox Action
actions =
  let
    singleton action =
      [action]
    fromList list =
      case list of
        [] -> NoOp
        (action::_) -> action
  in
    { address = Signal.forwardTo messages.address singleton
    , signal = Signal.map fromList messages.signal
    }

effectsAndModel : Signal (Model, Effects.Effects Action)
effectsAndModel =
  let
    updateJustModel action (model,_) = update action model
  in
    Signal.foldp updateJustModel init actions.signal

model : Signal Model
model =
  Signal.map fst effectsAndModel

port tasks : Signal (Task.Task Effects.Never ())
port tasks =
  Signal.map (Effects.toTask messages.address << snd) effectsAndModel

---------------

main =
  Signal.map (view actions.address) model

view address model =
  div []
    [ button [ onClick address GetShortenedUrl ] [ text "Get Shortened Url" ]
    , div []
      [ text "Shortened URL: "
      , text <| toString model.shortenedUrl
      ]
    ]