有人能为我提供弹簧启动服务器端事件的示例吗?
基本上我需要将服务器端事件推送到浏览器。我正在使用角度2和弹簧启动后端。请提供一个示例示例,我无法找到好的示例。
@Controller
public class SSEController {
private final List<SseEmitter> emitters = new ArrayList<>();
@RequestMapping(path = "/stream", method = RequestMethod.GET)
public SseEmitter stream() throws IOException {
SseEmitter emitter = new SseEmitter();
emitters.add(emitter);
emitter.onCompletion(() -> emitters.remove(emitter));
return emitter;
}
}
如何从服务器连续推送数据以及如何在Angular 2中订阅此事件?
提前致谢
没有人回答,所以回答我自己的问题。
有一个Spring Rest控制器
s色controller.Java
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.servlet.mvc.method.annotation.SseEmitter;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
@RestController
public class SSEController {
public static final List<SseEmitter> emitters = Collections.synchronizedList( new ArrayList<>());
@RequestMapping(path = "/stream", method = RequestMethod.GET)
public SseEmitter stream() throws IOException {
SseEmitter emitter = new SseEmitter();
emitters.add(emitter);
emitter.onCompletion(() -> emitters.remove(emitter));
return emitter;
}
}
service class.Java
public void sendSseEventsToUI(Notification notification) { //your model class
List<SseEmitter> sseEmitterListToRemove = new ArrayList<>();
SSEController.emitters.forEach((SseEmitter emitter) -> {
try {
emitter.send(notification, MediaType.APPLICATION_JSON);
} catch (IOException e) {
emitter.complete();
sseEmitterListToRemove.add(emitter);
e.printStackTrace();
}
});
SSEController.emitters.removeAll(sseEmitterListToRemove);
}
最后在Angular2组件中执行此操作
notification.component.ts
import {Component, OnInit} from '@angular/core';
declare let EventSource:any;
@Component({
selector: 'notification-cmp',
templateUrl: 'notification.component.html'
})
export class NotificationComponent implements OnInit {
connect(): void {
let source = new EventSource('http://localhost:8080/stream');
source.addEventListener('message', message => {
let n: Notification; //need to have this Notification model class in angular2
n = JSON.parse(message.data);
console.log(message.data);
});
}
}
上面的答案是一个很大的帮助。
和..
要接收推送的实际数据..
代码应该是
source.onmessage = (message)=>{
let n:Notification = JSON.parse(message.data);
}
source.addEventListener('message', message => {
// There is no data property available on 'message' here
let n: Notification;
n = JSON.parse(message.data);
console.log(message.data);
});
Pratap A.K的答案很棒。但为了保持它更清洁,你应该创建一个实现接口的NotificationService。像这样:
notification service imp了.Java
public class NotificationServiceImpl implements NotificationService {
public static final List<SseEmitter> emitters = Collections.synchronizedList(new ArrayList<>());
@Override
public SseEmitter initSseEmitters() {
SseEmitter emitter = new SseEmitter();
emitters.add(emitter);
emitter.onCompletion(() -> emitters.remove(emitter));
return emitter;
}
@Override
public void sendSseEventsToUI(WebSource notification) {
List<SseEmitter> sseEmitterListToRemove = new ArrayList<>();
this.emitters.forEach((SseEmitter emitter) -> {
try {
emitter.send(notification, MediaType.APPLICATION_JSON);
} catch (IOException e) {
emitter.complete();
sseEmitterListToRemove.add(emitter);
e.printStackTrace();
}
});
this.emitters.removeAll(sseEmitterListToRemove);
}
}
notification service.Java
public interface NotificationService {
public SseEmitter initSseEmitters();
public void sendSseEventsToUI(WebSource notification);
}
SS E controller.Java
@RestController
@RequestMapping("/mystream")
public class SSEController {
@Autowired
NotificationServiceImpl INotificationServiceImpl;
@CrossOrigin
@RequestMapping(path = "/streamsource", method = RequestMethod.GET)
public SseEmitter stream() throws IOException {
return INotificationServiceImpl.initSseEmitters();
}
}
最好的祝福