How to save the file that came from the server in the desired retrofit android format?

Question

Android

I am creating an application that sends different requests to the server using retrofit. One of these requests is a request for a file attached to a letter. Here I registered this request in the interface:

@Headers({"Content-type:application/json"})
Call<FileData> getAttach(@Header("Authorization") String token, @Path("id") Integer id, @Path("attach_file_name") String file_name, @Query("type") int type);

Here is the FileData class that is used in the request:

public class FileData {
    @SerializedName("size")
    @Expose
    private double size;
    @SerializedName("name")
    @Expose
    private String name;

    public FileData(double size, String name) {
        this.size = size;
        this.name = name;
    }

    public double getSize() {
        return Math.round(size * 100.0) / 100.0;
    }

    public String getName() {
        return name;
    }
}

and then here I am sending a request in the class:

mAPIService.getAttach("Bearer " + access_token, id, name, ty_pe).enqueue(new Callback<FileData>() {
            @Override
            public void onResponse(@NonNull Call<FileData> call, @NonNull Response<FileData> response) {
                if(response.isSuccessful())
                {

                }
            }

            @Override
            public void onFailure(@NonNull Call<FileData> call, @NonNull Throwable t) {

            }
        });

and here are a few examples of how the attached file comes to me in the answer:
picture:

200 OK https://сервер/v1/message/1303758/attachment/575b3981-4372-4104-98f3-a9eee386a0d5.jpg?type=1 (215ms)
        Content-Length: 107625
        Content-Disposition: attachment; filename="575b3981-4372-4104-98f3-a9eee386a0d5.jpg"
        P3P: policyref="/w3c/p3p.xml", CP="NOI ADM DEV COM NAV OUR STP"
    08-27 11:17:01.040 D: Keep-Alive: timeout=5, max=100
        Connection: Keep-Alive
        Content-Type: image/jpeg

or here is an empty text document:

200 OK https://сервер/v1/message/1303651/attachment/%D0%9D%D0%BE%D0%B2%D1%8B%D0%B9%20%D1%82%D0%B5%D0%BA%D1%81%D1%82%D0%BE%D0%B2%D1%8B%D0%B9%20%D0%B4%D0%BE%D0%BA%D1%83%D0%BC%D0%B5%D0%BD%D1%82.txt?type=1 (224ms)
    Content-Disposition: attachment; filename="Новый текстовый документ.txt"
    Vary: Accept-Encoding
    P3P: policyref="/w3c/p3p.xml", CP="NOI ADM DEV COM NAV OUR STP"
    Keep-Alive: timeout=5, max=100
    Connection: Keep-Alive
    Content-Type: text/plain; charset=utf-8

if there is some text in the document, for example, then in the response, respectively, the text that is in the document comes.
I can't figure out how to save any dock format, not just text. For example, a picture, or an archive (for an archive, I don’t understand how this will happen at all), an html link. At the very least, the name can be pulled out of the request, or from the response, the size is optional, but here's how to create a new file with the extension I need and with the correct content. If someone was engaged in this kind of development, then I will be very grateful for useful advice and any information.

Answer 1

Judging by the type of class FileDataused GSON. It is intended, as far as I know, to work with JSONfiles. Using GsonConverter for Retrofit2you will be able to get the desired FileData, but only if the server sends a response in the format JSONconstantly. If attachments come in the form of arbitrary files, then it may be more convenient for you to receive a set of bytes:

@Override
        public void onResponse(Response response) throws IOException {
            response.body().byteStream(); // Read the data from the stream
        }

Last copied from here .
In general, a good guide for downloading files with help Retrofitis here