Decoding function is not a Bytes.Decoder

[Gloix]

Currently the decoder is a simple converter of Bytes to Maybe Image, but elm/http requires a Bytes.Decoder, so the given image loading example does not work.

[miniBill]

If you need to convert from Bytes -> Maybe Image to Bytes.Decoder Image you can use Bytes.bytes and Bytes.andThen

[Gloix]

The problem is something like in Example#2 in Readme

Http.get
   { url = "/image.png"
   , expect = Http.expectBytes GotImage Image.decode
   }

Http.expectBytes is being passed Image.decode as second param, and that fails (at least in elm/http 2.0.0).

What you're suggesting implies knowing the number of bytes in advance, since Bytes.Decode.bytes needs a number of bytes to decode.

The solution that I found is to use

Http.get
    { url = path
    , expect = Http.expectBytesResponse GotImage httpResponseToImage
    }

httpReponseToImage : Http.Response Bytes -> Result Http.Error (Maybe Image)
httpReponseToImage response =    
    case response of
        Http.GoodStatus_ _ body ->
            Ok <| Image.decode body

        Http.BadUrl_ url ->
            Err (Http.BadUrl url)

        Http.Timeout_ ->
            Err Http.Timeout

        Http.NetworkError_ ->
            Err Http.NetworkError

        Http.BadStatus_ metadata _ ->
            Err (Http.BadStatus metadata.statusCode)