Loading GZIP JSON file using AJAX

Question

I have gzipped json file using below algorithm (from: java gzip can't keep original file's extension name)

private static boolean compress(String inputFileName, String targetFileName){
         boolean compressResult=true;
         int BUFFER = 1024*4;
         byte[] B_ARRAY = new byte[BUFFER]; 
         FileInputStream fins=null;
         FileOutputStream fout=null;
         GZIPOutputStream zout=null;
         try{
             File srcFile=new File(inputFileName);
             fins=new FileInputStream (srcFile);
             File tatgetFile=new File(targetFileName);
             fout = new FileOutputStream(tatgetFile);
             zout = new GZIPOutputStream(fout);
             int number = 0; 
             while((number = fins.read(B_ARRAY, 0, BUFFER)) != -1){
                 zout.write(B_ARRAY, 0, number);  
             }
         }catch(Exception e){
             e.printStackTrace();
             compressResult=false;
         }finally{
             try {
                zout.close();
                fout.close();
                fins.close();
            } catch (IOException e) {
                e.printStackTrace();
                compressResult=false;
            }
         }
         return compressResult;
    }

I am returning the JSON

response.setHeader("Content-Type", "application/json");
response.setHeader("Content-Encoding", "gzip");
response.setHeader("Vary", "Accept-Encoding");
response.setContentType("application/json");
response.setHeader("Content-Disposition","gzip");
response.sendRedirect(filePathurl);

or

request.getRequestDispatcher(filePathurl).forward(request, response);

Trying to access the JSON object using AJAX code as below:

$.ajax({
    type : 'GET',
    url : url,
    headers : {'Accept-Encoding' : 'gzip'},
    dataType : 'text',

The output I see is the binary data, not the decompressed JSON string. Any suggestion on how to make this work? Note that the Browsers I am using (IE, Chrome, FF) supports gzip as all my static contents which are gzipped by Apache are rendered correctly.

Titograd

Answer 1

By using:

response.sendRedirect(filePathurl);

You are creating another request/response. The headers you have defined are no longer associated with the file that actually gets sent.

Rather than sending a redirect, you need to load up your file and stream it in the same response.

Use Fiddler or another request viewer to see this.

Zymogen

thanks for your response. Fiddler confirms your view; I tried forward method also, in which fiddler shows the correct header, and when I view the uncompressed text, i can see the JSON; but the AJAX code is not reading the output as JSON. I am looking for solution (if feasible) to avoid reading and streaming the file. – Titograd

Answer 2

We can not override Accept-Encoding from browser/js etc anymore.

Loon