我已经写了一小段代码来生成服务器发送的事件,并编写了相应的JavaScript客户端来记录所有消息。当我发送请求时,我可以在chrome的网络标签中看到浏览器正在接收来自服务器的所有消息,但是在JavaScript中,仅触发了打开事件监听器,而从未触发过消息监听器。我花了很多时间在此上,但没有成功。
这是生成SSE的Java代码:
@GET
@Path("/updates/sse")
@Produces(MediaType.SERVER_SENT_EVENTS)
public void publishUpdates(@Context SseEventSink sseEventSink) {
new Thread(() -> {
for (int i = 0; i < 10; i++) {
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
final OutboundSseEvent event = sse.newEventBuilder()
.name("message-to-client")
.data(String.class, "Hello world " + i + "!")
.build();
sseEventSink.send(event);
}
}).start();
}
这是我的JavaScript代码来处理响应:
if(typeof(EventSource) !== "undefined") {
var source = new EventSource("/gra/services/updates/sse");
source.addEventListener('message', function(e) {
console.log("message");
console.log(e.data);
}, false);
source.addEventListener('open', function(e) {
// Connection was opened.
console.log("open");
}, false);
source.addEventListener('error', function(e) {
console.log("error");
console.log(e);
if (e.readyState == EventSource.CLOSED) {
// Connection was closed.
}
}, false);
} else {
document.getElementById("result").innerHTML = "Sorry, your browser does not support server-sent events...";
}
这是我在Chrome的“网络”标签中看到的内容:
我试图找出浏览器是否正在接收事件数据,为什么不调用消息侦听器。
答案 0 :(得分:1)
请参见example in documentation for EventSource:
/* The event "message" is a special case, as it
* will capture events without an event field
* as well as events that have the specific type
* `event: message` It will not trigger on any
* other event type.
*/
sse.addEventListener("message", function(e) {
console.log(e.data)
})
您的邮件类型为message-to-client
,而不是“无”。