The karaf log of SDNR component has the following last DEBUG output for the MR consumer polling function (fetchWithReturnConsumerResponse), after 22h hours running

2020-05-28T14:53:47,827 | DEBUG | Thread-61 | HttpURLConnection | - - | - | sun.net.www.messageheader@2c24234c6 pairs: *{GET /events/XXXXXX?timeout=50000 HTTP/1.1: null} {Authorization: Basic XXXXXX=} {User-Agent: Jersey/2.25.1 (HttpUrlConnection 1.8.0_222)} {Host: YYYYYYYYY} {Accept: text/html, image/gif, image/jpeg, ; q=.2, /; q=.2} {Connection: keep-alive}

2020-05-28T14:53:47,828 | DEBUG | Thread-62 | HttpURLConnection | - - | - | sun.net.www.messageheader@45d206956 pairs: *{GET /events/XXXXXX?timeout=50000 HTTP/1.1: null} {Authorization: Basic XXXXXX=} {User-Agent: Jersey/2.25.1 (HttpUrlConnection 1.8.0_222)} {Host: YYYYYYYYY} {Accept: text/html, image/gif, image/jpeg, ; q=.2, /; q=.2} {Connection: keep-alive}

No answer coming back, get/answer cycle not completed. Observation with TransportType = HTTPAAF
Problems: Timeout of 50000ms forwarded to DMaaP Server and not handled by client. Client waits endless if TCP/IP connection remains open, but server is not answering for any reason (Potential issue is that the server internal timeout message gets lost)

The dmaapclient library needs to implement a readtimeout so that if for some reason the server does not respond in a stipulated time, the client times out and resumes the remaining flow instead of endlessly waiting for a server response. The dmaap-listener in ccsdk/sli/northbound has a custom implementation of such a functionality using jax-rs to workaround the issue of the dmaapclient library.

ClientBuilder clientBuilder = ClientBuilder.newBuilder();
clientBuilder.connectTimeout(connectTimeoutSeconds, TimeUnit.SECONDS);
clientBuilder.readTimeout(readTimeoutMinutes, TimeUnit.MINUTES);
return clientBuilder.build();