在Elm中指定Http頭

Question

我的Elm程序使用http.get的代碼（摘錄）正常工作，但我不得不將其更改爲自定義請求以在頭中指定JWT，並且由於類型不匹配而出現以下錯誤。

我想我需要將request的類型更改爲Http.Request (List QFields)，但不知道如何去做。顯然，我不能讓它像{ verb = "Get" ...} decoder，因爲{ verb ... }是不是一個函數。

The 2nd argument to function `send` is causing a mismatch. 

264|    Http.send FetchHNTopStories request 
               ^^^^^^^ 
Function `send` is expecting the 2nd argument to be: 

    Http.Request (List QFields) 

But it is: 

    Request 

---

<Working code> 

request : Http.Request (List QFields) 
request = 
    let 
     decoder = 
     JD.at [ "data", "qQry" ] <| 
      JD.list qDecoder 
    in 
     Http.get ("http://localhost:3000/graphql?query=" ++ encoded) decoder 

type Msg 
    = SendMessage 
    | FetchHNTopStories (Result Http.Error (List QFields)) 
    ... 

initModel : Taco -> (Model, Cmd Msg) 
initModel taco = 
    let 
     startModel = { newMessage = "" 
        } 

     cmd = Http.send FetchHNTopStories request 
    in 
     (startModel 
      ! [cmd] 
     ) 

---

<Changed code - Not working> 

request : Request 
request = 
    let 

     decoder = 
      JD.at [ "data", "Qry" ] <| 
       JD.list qDecoder 

     headers= [ 
      ("Authorization","Bearer eyJhbGciOiJIUzUxM...kv6TGw7H1GX2g") 
     ] 

    in 
      { verb = "GET" 
      , headers = headers 
      , url = url 
      , body = Http.emptyBody 
      , expect = Http.expectJson decoder 
      } 

Answer 1

如果我理解正確的話，你需要使用Http.request，而不是Http.get，並提供一個有效的記錄，像這樣：

request : Http.Request (List QFields) 
request = 
    let 

     decoder = 
      JD.at [ "data", "Qry" ] <| 
       JD.list qDecoder 

     headers= [ 
      ("Authorization","Bearer eyJhbGciOiJIUzUxM...kv6TGw7H1GX2g") 
     ] 

    in 
     Http.request -- This line is missing from your code 
      { method = "GET" 
      , headers = headers 
      , url = url 
      , body = Http.emptyBody 
      , expect = Http.expectJson decoder 
      , timeout = Nothing 
      , withCredentials = False 
      }