I'm downloading a file using a Retrofit2 implementation of a REST API, per the nice tutorial at https://futurestud.io/tutorials/retrofit-2-how-to-download-files-from-server.
My API interface declares the @GET as @Streaming, and indeed when I read from the InputStream given me by byteStream(), I can read the entire 29 MB file.
What I'd like to do is read it all in 4 MB chunks, so I'm using Okio's handy BufferedSource. The problem is that my call to request(4*1024*1024) returns true only once, though the total file size is something on the order of 29 MB.
My Java:
@Streaming @GET Call<ResponseBody> get(@Url String url);
// ...
Response<ResponseBody> response = api.get("https://my.file.url");
final int bufSize = 4*1024*1024;
byte[] buffer;
long total;
InputStream is = response.body().byteStream();
BufferedSource ss = Okio.buffer(Okio.source(is));
// Is this the same as ss=response.body().source() ??
while (ss.request(bufSize)) {
buffer = ss.readByteArray();
total += doSomethingUsefulWith(buffer);
System.out.println("Running total: " + total);
}
// Capture the < 4MB residue
buffer = ss.readByteArray();
if (buffer.length > 0) {
total += doSomethingUsefulWith(buffer);
System.out.println("Total: " + total);
}
System.out.println("That's all, folks!");
Console output:
Running total: 4194304
That's all, folks!
Again, the raw InputStream does give me the full 29 MB, I've done it before. Do I misunderstand request()? What am I doing wrong?
