| Re: [jetty-dev] Calling startAsync() on a servlet request throws java.lang.IllegalStateException: s=DISPATCHED i=true a=STARTED |
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Hi Simone, > The real question is: why you call startAsync() in your filter and then chain to the ProxyServlet? Using AsyncListener, I want to wait for the "completion" of the requests whose URLs are mapped to my filter, so that I can perform some specific operations in the AsyncListener's onComplete() method. For example, if the request to create
a search object in Kibana is completed, I want to create a new object in my application and also generate an audit event.
Anyway, I fixed the IllegalStateException as follows:
1.
The listener related code segment was located BEFORE the filter’s “chain.doFilter()” call. I moved this code segment to a position AFTER the filter’s "chain.doFilter()" call, so that I can retrieve the AsyncContext that is "already created"
in the Jetty ProxyServlet's service() method. I can then add an AsyncListener to the retrieved AsyncContext.
2.
I changed the “request.startAsync()” call in my filter to “request.getAsyncContext()” so that I am not starting a new AsyncContext which leads to the IllegalStateException, but only retrieving the AsyncContext that is already created
in Jetty’s ProxyServlet. So the updated code segment looks like this: chain.doFilter(myRequestWrapper, response); AsyncContext asyncContext = myRequestWrapper.getAsyncContext(); asyncContext.addListener(new AsyncListener() {
@Override public void onTimeout(AsyncEvent event) throws IOException
{ logger.log(Level.WARNING, "Async timeout..."); }
@Override public void onStartAsync(AsyncEvent event) throws IOException
{ logger.log(Level.INFO, "Async start..."); }
@Override public void onError(AsyncEvent event) throws IOException
{ logger.log(Level.SEVERE, "Async error..."); }
@Override public void onComplete(AsyncEvent event) throws IOException
{ HttpServletResponse httpResponse = (HttpServletResponse) event.getSuppliedResponse(); //HttpServletResponse httpResponse = (HttpServletResponse) event.getAsyncContext().getResponse(); if (httpResponse.getStatus() == HttpServletResponse.SC_OK || httpResponse.getStatus() == HttpServletResponse.SC_CREATED ) { //some business logic } } }, myRequestWrapper, httpServletResponse); Thanks a lot for your response… Regards, Sanjay ---------------------------------------------------------------------- Date: Tue, 21 Feb 2017 23:14:37 +0100 From: Simone Bordet <sbordet@xxxxxxxxxxx> To: "Jetty @ Eclipse developer discussion list" Subject: Re: [jetty-dev] Calling startAsync() on a servlet request throws java.lang.IllegalStateException: s=DISPATCHED i=true a=STARTED Message-ID: <CAFWmRJ0OrqcF7tQOi2OsyfZxwUfY67QQ-HAP0qC0FXf5_K+RJA@xxxxxxxxxxxxxx> Content-Type: text/plain; charset=UTF-8 Hi, On Tue, Feb 21, 2017 at 6:47 PM, Sanjay Bhat <Sanjay.Bhat@xxxxxxxxxxxxxx> wrote: > Is the "IllegalStateException" being thrown because the startAsync()
> method is being called twice on the same request - for the first time
> in my filter and for the second time in Jetty ProxyServlet's service() method? Yes. > If yes, is there no way to use an "AsyncListener" in a filter chain
> that is terminated by Jetty's ProxyServlet? Multiple startAsync() calls are supported by the Servlet Spec (and of course in Jetty), but only in consecutive cycles. The real question is: why you call startAsync() in your filter and then chain to the ProxyServlet ? -- Simone Bordet ---- Developer advice, training, services and support from the Jetty & CometD experts. ------------------------------ |