Http 我想在Elm中初始化函数_Http_Elm

Http 我想在Elm中初始化函数

http elm

Http 我想在Elm中初始化函数,http,elm,Http,Elm,我正在尝试将flags值从Main.elm传递到Top.elm 并运行一个名为“getToken”的函数，该函数具有标志值。但是，这个函数“getToken”似乎不能正常工作我的主要朋友埃尔姆是 type alias Model = { key : Nav.Key , page : Page } type Page = NotFound | TopPage ( Page.Top.Model, Cmd Page.Top.Msg ) | Art

我正在尝试将flags值从Main.elm传递到Top.elm 并运行一个名为“getToken”的函数，该函数具有标志值。但是，这个函数“getToken”似乎不能正常工作

我的主要朋友埃尔姆是

type alias Model =
    { key : Nav.Key
    , page : Page
    }


type Page
    = NotFound
    | TopPage ( Page.Top.Model, Cmd Page.Top.Msg )
    | ArticlePage Page.Article.Model


init : String -> Url.Url -> Nav.Key -> ( Model, Cmd Msg )
init flags url key =
    Model key (TopPage (Page.Top.init flags))
        |> goTo (Route.parse url)

type alias Model =
    { status : LoadingStatus
    }


type LoadingStatus
    = Init
    | Waiting
    | Loaded Token
    | Failed Http.Error


init : String -> ( Model, Cmd Msg )
init token =
    ( Model Init
    , getToken token )

...

-- UPDATE


type Msg
    = GotToken (Result Http.Error Token)


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

        GotToken (Err err) ->
            ( { model | status = Failed err }, Cmd.none )




-- VIEW


view : Model -> Html Msg
view model =
    case model.status of
            Init ->
                text "sssssssssssssssssssssssssssss"

            Waiting ->
                text "waiting..."

            Loaded token ->
                div []
                    [ p [] [ text "yahoooooooo" ]
                    , p [] [ text token.accessToken ]
                    ]

            Failed e ->
                case e of
                    Http.BadBody message ->
                        pre [] [ text message ]

                    _ ->
                        -- text (Debug.toString e)
                        pre [] [ text "error" ]

...

type alias Token =
    { accessToken : String
    }


-- AccessToken


getToken : String -> Cmd Msg
getToken token =
    Http.request
        { method = "POST"
        , headers =
            [ Http.header "Authorization" ("Bearer " ++ token)
            , Http.header "Accept" "application/json"
            , Http.header "Content-Type" "application/json"
            ]
        , url = "http://localhost:8080/web_users/create"
        , expect = Http.expectJson GotToken tokenDecoder
        , body = Http.emptyBody
        , timeout = Nothing
        , tracker = Nothing
        }


tokenDecoder : Decoder Token
tokenDecoder =
    D.map Token
        (D.field "access_token" D.string)

我的上衣，埃尔姆是

type alias Model =
    { key : Nav.Key
    , page : Page
    }


type Page
    = NotFound
    | TopPage ( Page.Top.Model, Cmd Page.Top.Msg )
    | ArticlePage Page.Article.Model


init : String -> Url.Url -> Nav.Key -> ( Model, Cmd Msg )
init flags url key =
    Model key (TopPage (Page.Top.init flags))
        |> goTo (Route.parse url)

type alias Model =
    { status : LoadingStatus
    }


type LoadingStatus
    = Init
    | Waiting
    | Loaded Token
    | Failed Http.Error


init : String -> ( Model, Cmd Msg )
init token =
    ( Model Init
    , getToken token )

...

-- UPDATE


type Msg
    = GotToken (Result Http.Error Token)


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

        GotToken (Err err) ->
            ( { model | status = Failed err }, Cmd.none )




-- VIEW


view : Model -> Html Msg
view model =
    case model.status of
            Init ->
                text "sssssssssssssssssssssssssssss"

            Waiting ->
                text "waiting..."

            Loaded token ->
                div []
                    [ p [] [ text "yahoooooooo" ]
                    , p [] [ text token.accessToken ]
                    ]

            Failed e ->
                case e of
                    Http.BadBody message ->
                        pre [] [ text message ]

                    _ ->
                        -- text (Debug.toString e)
                        pre [] [ text "error" ]

...

type alias Token =
    { accessToken : String
    }


-- AccessToken


getToken : String -> Cmd Msg
getToken token =
    Http.request
        { method = "POST"
        , headers =
            [ Http.header "Authorization" ("Bearer " ++ token)
            , Http.header "Accept" "application/json"
            , Http.header "Content-Type" "application/json"
            ]
        , url = "http://localhost:8080/web_users/create"
        , expect = Http.expectJson GotToken tokenDecoder
        , body = Http.emptyBody
        , timeout = Nothing
        , tracker = Nothing
        }


tokenDecoder : Decoder Token
tokenDecoder =
    D.map Token
        (D.field "access_token" D.string)

服务器启动后，可以在视图中看到文本“SSSSSSSSS”。看来Top.elm中的Init正在工作。但是，它不会走得更远

我假设getToken函数在这里不起作用，因为我只能看到LoadingStatus Init（未等待、已加载、已失败）

有人知道为什么getToken函数不能正常工作吗

没有发生错误。

最有可能的是，来自

Top.init的命令没有到达运行时
我看到您编码了TopPage（Page.Top.Model，Cmd Page.Top.Msg）
。这很可能是罪魁祸首。您需要类似于TopPage Page.Top.Model
的内容，并确保Top.init
返回的命令与Main.init

它看起来是这样的：
init : String -> Url.Url -> Nav.Key -> ( Model, Cmd Msg )
init flags url key =
    let
        ( topModel, topCmd ) =
            Page.Top.init flags

        ( mainModel, mainCmd ) =
            Model key (TopPage topModel)
                |> goTo (Route.parse url)
    in
    ( mainModel, Cmd.batch [ mainCmd, topCmd ] )

最有可能的是，来自Top.init
的命令没有到达运行时
我看到您编码了TopPage（Page.Top.Model，Cmd Page.Top.Msg）
。这很可能是罪魁祸首。您需要类似于TopPage Page.Top.Model
的内容，并确保Top.init
返回的命令与Main.init

它看起来是这样的：
init : String -> Url.Url -> Nav.Key -> ( Model, Cmd Msg )
init flags url key =
    let
        ( topModel, topCmd ) =
            Page.Top.init flags

        ( mainModel, mainCmd ) =
            Model key (TopPage topModel)
                |> goTo (Route.parse url)
    in
    ( mainModel, Cmd.batch [ mainCmd, topCmd ] )

也许服务器挂起了？浏览器的调试器对此有何评论？谢谢！实际上它还没有到达服务器。浏览器调试器什么也没说。你能提供一个吗？看看开发控制台的网络选项卡服务器挂起的原因吗？浏览器的调试器对此有何评论？谢谢！实际上它还没有到达服务器。浏览器调试器什么也没说。你能提供一个吗？看看开发控制台的网络选项卡