@Override
protected void service(final HttpServletRequest request, final HttpServletResponse response) throws ServletException, IOException {
log.trace("Service: {}", request);
// is there a consumer registered for the request.
HttpConsumer consumer = resolve(request);
if (consumer == null) {
response.sendError(HttpServletResponse.SC_NOT_FOUND);
return;
}
if (consumer.getEndpoint().getHttpMethodRestrict() != null
&& !consumer.getEndpoint().getHttpMethodRestrict().equals(request.getMethod())) {
response.sendError(HttpServletResponse.SC_METHOD_NOT_ALLOWED);
return;
}
if ("TRACE".equals(request.getMethod()) && !consumer.isTraceEnabled()) {
response.sendError(HttpServletResponse.SC_METHOD_NOT_ALLOWED);
return;
}
final Exchange result = (Exchange) request.getAttribute(EXCHANGE_ATTRIBUTE_NAME);
if (result == null) {
// no asynchronous result so leverage continuation
final Continuation continuation = ContinuationSupport.getContinuation(request);
if (continuation.isInitial() && continuationTimeout != null) {
// set timeout on initial
continuation.setTimeout(continuationTimeout);
}
// are we suspended and a request is dispatched initially?
if (consumer.isSuspended() && continuation.isInitial()) {
response.sendError(HttpServletResponse.SC_SERVICE_UNAVAILABLE);
return;
}
if (continuation.isExpired()) {
String id = (String) continuation.getAttribute(EXCHANGE_ATTRIBUTE_ID);
// remember this id as expired
expiredExchanges.put(id, id);
log.warn("Continuation expired of exchangeId: {}", id);
response.sendError(HttpServletResponse.SC_SERVICE_UNAVAILABLE);
return;
}
// a new request so create an exchange
final Exchange exchange = new DefaultExchange(consumer.getEndpoint(), ExchangePattern.InOut);
if (consumer.getEndpoint().isBridgeEndpoint()) {
exchange.setProperty(Exchange.SKIP_GZIP_ENCODING, Boolean.TRUE);
exchange.setProperty(Exchange.SKIP_WWW_FORM_URLENCODED, Boolean.TRUE);
}
if (consumer.getEndpoint().isDisableStreamCache()) {
exchange.setProperty(Exchange.DISABLE_HTTP_STREAM_CACHE, Boolean.TRUE);
}
HttpHelper.setCharsetFromContentType(request.getContentType(), exchange);
exchange.setIn(new HttpMessage(exchange, request, response));
// set context path as header
String contextPath = consumer.getEndpoint().getPath();
exchange.getIn().setHeader("CamelServletContextPath", contextPath);
String httpPath = (String)exchange.getIn().getHeader(Exchange.HTTP_PATH);
// here we just remove the CamelServletContextPath part from the HTTP_PATH
if (contextPath != null
&& httpPath.startsWith(contextPath)) {
exchange.getIn().setHeader(Exchange.HTTP_PATH,
httpPath.substring(contextPath.length()));
}
if (log.isTraceEnabled()) {
log.trace("Suspending continuation of exchangeId: {}", exchange.getExchangeId());
}
continuation.setAttribute(EXCHANGE_ATTRIBUTE_ID, exchange.getExchangeId());
// we want to handle the UoW
try {
consumer.createUoW(exchange);
} catch (Exception e) {
log.error("Error processing request", e);
throw new ServletException(e);
}
// must suspend before we process the exchange
continuation.suspend();
ClassLoader oldTccl = overrideTccl(exchange);
if (log.isTraceEnabled()) {
log.trace("Processing request for exchangeId: {}", exchange.getExchangeId());
}
// use the asynchronous API to process the exchange
consumer.getAsyncProcessor().process(exchange, new AsyncCallback() {
public void done(boolean doneSync) {
// check if the exchange id is already expired
boolean expired = expiredExchanges.remove(exchange.getExchangeId()) != null;
if (!expired) {
if (log.isTraceEnabled()) {
log.trace("Resuming continuation of exchangeId: {}", exchange.getExchangeId());
}
// resume processing after both, sync and async callbacks
continuation.setAttribute(EXCHANGE_ATTRIBUTE_NAME, exchange);
continuation.resume();
} else {
log.warn("Cannot resume expired continuation of exchangeId: {}", exchange.getExchangeId());
}
}
});
if (oldTccl != null) {
restoreTccl(exchange, oldTccl);
}
// return to let Jetty continuation to work as it will resubmit and invoke the service
// method again when its resumed
return;
}
try {
// now lets output to the response
if (log.isTraceEnabled()) {
log.trace("Resumed continuation and writing response for exchangeId: {}", result.getExchangeId());
}
Integer bs = consumer.getEndpoint().getResponseBufferSize();
if (bs != null) {
log.trace("Using response buffer size: {}", bs);
response.setBufferSize(bs);
}
consumer.getBinding().writeResponse(result, response);
} catch (IOException e) {
log.error("Error processing request", e);
throw e;
} catch (Exception e) {
log.error("Error processing request", e);
throw new ServletException(e);
} finally {
consumer.doneUoW(result);
}
}