How to synchronize Servlet client transaction? - restcomm

Question

Hello I am currently using restcomm-sip-servlets-4.0.75-apache-tomcat-8.0.26. and I am having issues canceling an ongoing request from the http request thread. I noticed that this issue only appears to happen when I create a new request with an auth header like so :
AuthInfo authInfo = sipFactory.createAuthInfo();
authInfo.addAuthInfo(
response.getStatus(),
realm,myauth,password);
SipServletRequest challengeRequest = response.getSession().createRequest(
response.getRequest().getMethod());
(String)session.getAttribute("FirstPartyContent");
if(session.getAttribute("FirstPartyContent") !=null){
challengeRequest.setContent(session.getAttribute("FirstPartyContent"),(String) session.getAttribute("FirstPartyContentType"));
}
challengeRequest.addAuthHeader(response, authInfo);
challengeRequest.getFrom().setDisplayName(auth.getDisplayName());
session.removeAttribute("original");
session.setAttribute("original", challengeRequest);
challengeRequest.send();
When a request comes in via the http interface I look for the SipApplicationSession like so:
SipSessionsUtil sipSessionsUtil =
(SipSessionsUtil) session.getServletContext().
getAttribute("javax.servlet.sip.SipSessionsUtil");
logger.info("found servlet contxt for sipsession util");
SipApplicationSession tobecancelledsess = sipSessionsUtil.getApplicationSessionById(sessionapplicationID);
I then create a cancel request from the session request stored like so :
SipServletRequest req = (SipServletRequest)tobecancelledsess.getAttribute("original");
drequest = req.createCancel();
although the remote server responds a provisional with to-tag I get:
2017-04-28 16:26:04,470 DEBUG [SipServletMessageImpl] (http-bio-8443-exec-1) transaction null transactionId = null transactionType false
2017-04-28 16:26:04,470 DEBUG [SipServletMessageImpl] (http-bio-8443-exec-1) transaction null transactionId = null transactionType false
java.lang.IllegalStateException: No client transaction found! null
at org.mobicents.servlet.sip.message.SipServletRequestImpl.createCancel(SipServletRequestImpl.java:258)
at org.example.servlet.sip.CallContainer.CancelSession(CallContainer.java:319)
at org.example.servlet.sip.CallContainer.CheckCancel(CallContainer.java:274)
at org.example.servlet.sip.SimpleWebServlet.doPut(SimpleWebServlet.java:360)
at org.example.servlet.sip.SimpleWebServlet.service(SimpleWebServlet.java:149)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:291)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:219)
at org.mobicents.servlet.sip.startup.SipStandardContextValve.invoke(SipStandardContextValve.java:262)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:142)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:616)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:518)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1091)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:673)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:279)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:745)
I noticed that when I cancel the request from the servlet class I don't have this issue.

Answer 1

I found that setting a context attribute at the response like this solves my issue:
if (resp.getStatus() == SipServletResponse.SC_RINGING){
SipSession session = resp.getSession();
resp.getSession().getServletContext().setAttribute("ringing",true);
}
I then grab the session context like this
SipServletRequest req = (SipServletRequest)tobecancelledsess.getAttribute("original");
Boolean ringed = (Boolean ) tobecancelledsess.getServletContext().getAttribute("ringing");
if(ringed == Boolean.True)
drequest = req.createCancel();
and eventually you need to send the cancel request with send();