Error for modify body before gzip response

[nnzbz]

Questions

Error for modify body before gzip response，browser developer tools network show "(failed)net::ERR_CONTENT_DECODING_FAILED"

Version

4.5.8

Context

My code referenced https://vertx.io/docs/vertx-http-proxy/java/#_interception_control, but when proxy response gzip occur "ERR_CONTENT_DECODING_FAILED" error in brower.

Do you have a reproducer?

No

Steps to reproduce

No

Extra

No

[tsegismont]

Can you please add more info to help us reproduce?

• sample client request
• proxy setup (snippets)
• sample backend response

A complete reproducer is even better

[nnzbz]

client request:

response:

server http config:

proxy config(forward kibana):

modify code:

[tsegismont]

So, if I understand correctly:

• the proxy is between the browser and Kibana
• Kibana uses gzip compression for responses

Correct?

[nnzbz]

Yes, that's right

[tsegismont]

I was able to reproduce.

The problem is that the Kibana response body is encoded with gzip (as indicated by the content-encoding header). So when you get the buffered content (with BufferingWriteStream) you cannot transform to String, because you're actually looking at binary content.

Instead, you must create the response like this:

          Buffer content = bufferingWriteStream.content();
          proxyResponse.setBody(Body.body(content));
          return context.sendResponse();

If you want to inspect the string content, you can do it like this:

          ByteArrayOutputStream baos = new ByteArrayOutputStream();
          try (GZIPInputStream gis = new GZIPInputStream(new ByteArrayInputStream(content.getBytes()))) {
            byte[] buffer = new byte[1024];
            int len;
            while ((len = gis.read(buffer)) != -1) {
              baos.write(buffer, 0, len);
            }
          } catch (IOException e) {
            throw new RuntimeException(e);
          }
          String html = baos.toString(StandardCharsets.UTF_8);