How to get gziped xml files with retrofit?

Question

I'm using retrofit to get the data from the web. now my problem is that I have to get a gziped file and retrofit needs some kind of headers that I dont know how to implement right, obviously. I did a research on this but nothing seems to help since most developers are using json.

Here is what I'm trying to do:

  Retrofit retrofit = new Retrofit.Builder()
            .baseUrl("this is my baseurl")
            .addConverterFactory(SimpleXmlConverterFactory.create())
            .build();

and my interface:

 public interface RestAPI {

    @GET("main_data1.gz")
    Call<Meritum> getData();

    @GET("terms1_EN.gz")
    Call<MeritumTerms> getTerms();

    @GET
    Call<GameResults> getResults(@Url String url);

}

So I'm trying to get that gziped file and I always get response like this:

So what do I need to add so that retrofit recognizes that gzip file?

Answer 1

You shouldn't specify any headers.

I built a mini server that just responds the following XML gzipped:

<task>
    <id link="http://url-to-link.com/task-id">1</id>
    <title>Retrofit XML Converter Blog Post</title>
    <description>Write blog post: XML Converter with Retrofit</description>
    <language>de-de</language>
</task>

After running the server, I can get the XML by using curl:

curl http://localhost:1337/ -v --compressed

I can see the XML correctly and the server responds with the following headers:

Content-Encoding: gzip
Content-Type: application/xml; charset=utf-8

Knowing that the server responds with a gzipped response, now I try to make it work in Android:

I'm using the following in build.gradle:

compile 'com.squareup.retrofit2:retrofit:2.1.0'
compile ('com.squareup.retrofit2:converter-simplexml:2.1.0') {
    exclude group: 'xpp3', module: 'xpp3'
    exclude group: 'stax', module: 'stax-api'
    exclude group: 'stax', module: 'stax'
}

This is the retrofit instance configuration:

Retrofit retrofit = new Retrofit.Builder()
            .baseUrl(BASE_URL)
            .addConverterFactory(SimpleXmlConverterFactory.create())
            .build();

This is the interface:

public interface MyApiEndpointInterface {
    @GET("/")
    Call<Task> getInfo();
}

This is my Task class:

@Root(name = "task")
public class Task {
    @Element(name = "id")
    private long id;

    @Element(name = "title")
    private String title;

    @Element(name = "description")
    private String description;

    @Element(name = "language")
    private String language;

    @Override
    public String toString() {
        return "Task{" +
                "id=" + id +
                ", title='" + title + '\'' +
                ", description='" + description + '\'' +
                ", language='" + language + '\'' +
                '}';
    }
}

I can confirm that it is working by doing the following:

call.enqueue(new Callback<Task>() {
            @Override
            public void onResponse(Call<Task> call, Response<Task> response) {
                if (response.isSuccessful()) {
                    Log.d("MainActivity", response.body() + "");
                    ...