Question

问题很简单，我如何将redux-observable与EventSource一起使用？

与RxJs一样：

const observable = Observable.create(observer => {
  const eventSource = new EventSource('/model-observable');
  return () => {
    eventSource.close();
  };
});

observable.subscribe({
  next: data => {
    this.zone.run(() => this.someStrings.push(data));
  },
  error: err => console.error('something wrong occurred: ' + err)
});

Answer 1

这听起来更像是关于如何连接到EventSource的一般RxJS问题。这可以通过多种方式完成。如果您关心的只是消息（而不是错误/打开）：

import requests
import time

def ColorRequest():
    url = 'http://csgoroll.com/v1/roulette/state?token=bcb7841fe779ac0ae2a9e4f882ed3961ce0d714215fede3c025a24fc418e123dcb5a0a47a0ba1825225c14b39e08ea399422eb2b012689a79c41f42b529640e37d5374125c3fef409b2d165c223923dbc27f320c53bf10e46e701058251c97b9'  # Could add a + pls str(pagesomething) to add on to the url so that it would update
    sourcecode = requests.get(url)  # requests the data from the site
    obj = sourcecode.json()
    for roll in obj['rolls']:
        print(roll['id'], roll['roll'])

if __name__ == '__main__':
    while True:
        ColorRequest()
        time.sleep(1000)   # these are seconds, ~17min

如果您关心开放和/或错误，则需要更多代码来管理所有内容：

import { fromEvent } from 'rxjs/observable/fromEvent';

const fromEventSource = url => {
  return new Observable(observer => {
    const source = new EventSource(url);
    const message$ = fromEvent(source, 'message');
    const subscription = message$.subscribe(observer);

    return () => {
      subscription.unsubscribe();
      source.close();
    };
  });
};

redux-observable中的用法将是这样的：

import { Observable } from 'rxjs/Observable';
import { Subscriber } from 'rxjs/Subscriber';

const fromEventSource = (url, openObserver) => {
  return new Observable(observer => {
    const open = new Subscriber(openObserver);
    const source = new EventSource(url);

    const onOpen = event => {
      open.next(event);
      open.complete();
    };

    const onError = event => {
      if (event.readyState === EventSource.CLOSED) {
        observer.complete();
      } else {
        observer.error(event);
      }
    };

    const onMessage = event => {
      observer.next(event.data);
    };

    source.addEventListener('open', onOpen, false);
    source.addEventListener('error', onError, false);
    source.addEventListener('message', onMessage, false);

    return () => {
      source.removeEventListener('open', onOpen, false);
      source.removeEventListener('error', onError, false);
      source.removeEventListener('message', onMessage, false);
      source.close();
    };
  });
};

fromEventSource('http://some-url.com')
  .subscribe(value => console.log(value));

如何使用Redux Observable的EventSource

1 个答案: