/**
* Send an SSE event prepared with the given builder. For example:
*
* <pre>
* // static import of SseEmitter
*
* SseEmitter emitter = new SseEmitter();
* emitter.send(event().name("update").id("1").data(myObject));
* </pre>
*
* @param builder a builder for an SSE formatted event.
* @throws IOException raised when an I/O error occurs
*/
public void send(SseEventBuilder builder) throws IOException {
Set<DataWithMediaType> dataToSend = ((SseEventBuilderImpl) builder).build();
synchronized (this) {
for (DataWithMediaType entry : dataToSend) {
super.send(entry.getData(), entry.getMediaType());
}
}
}
@Override
public void handleReturnValue(
Object returnValue,
MethodParameter returnType,
ModelAndViewContainer mavContainer,
NativeWebRequest webRequest)
throws Exception {
if (returnValue == null) {
mavContainer.setRequestHandled(true);
return;
}
HttpServletResponse response = webRequest.getNativeResponse(HttpServletResponse.class);
ServerHttpResponse outputMessage = new ServletServerHttpResponse(response);
if (ResponseEntity.class.isAssignableFrom(returnValue.getClass())) {
ResponseEntity<?> responseEntity = (ResponseEntity<?>) returnValue;
outputMessage.setStatusCode(responseEntity.getStatusCode());
outputMessage.getHeaders().putAll(responseEntity.getHeaders());
returnValue = responseEntity.getBody();
if (returnValue == null) {
mavContainer.setRequestHandled(true);
return;
}
}
ServletRequest request = webRequest.getNativeRequest(ServletRequest.class);
ShallowEtagHeaderFilter.disableContentCaching(request);
Assert.isInstanceOf(ResponseBodyEmitter.class, returnValue);
ResponseBodyEmitter emitter = (ResponseBodyEmitter) returnValue;
emitter.extendResponse(outputMessage);
// Commit the response and wrap to ignore further header changes
outputMessage.getBody();
outputMessage = new StreamingServletServerHttpResponse(outputMessage);
DeferredResult<?> deferredResult = new DeferredResult<Object>(emitter.getTimeout());
WebAsyncUtils.getAsyncManager(webRequest)
.startDeferredResultProcessing(deferredResult, mavContainer);
HttpMessageConvertingHandler handler =
new HttpMessageConvertingHandler(outputMessage, deferredResult);
emitter.initialize(handler);
}
@Override
protected void extendResponse(ServerHttpResponse outputMessage) {
super.extendResponse(outputMessage);
HttpHeaders headers = outputMessage.getHeaders();
if (headers.getContentType() == null) {
headers.setContentType(new MediaType("text", "event-stream"));
}
}
