Rxjs：重试一个承诺？

Question

想知道为什么我的承诺正在解决但尝试重试。

var getResultsStream = url => Rx.Observable.onErrorResumeNext( 
     Rx.Observable.defer( () => Rx.Observable
        .fromPromise( getSearchResults(url)
        .catch(error => Rx.Observable.of(`Error: ${error}`)) )
        .timeout(20000, new Error(`Timeout: ${url}`))
     )
     .do( e => console.log(`Retrying: ${url}`))
     .retry(3)
)

重试承诺 3 次是否更好？

Answer 1

除非您对 defer 和/或 onErrorResumeNext 有特殊用途，否则您可以将其全部扔掉并简单地使用：

const request = url => Rx.Observable.of(url)
        .do(url => console.log("requesting: " + url))
        .switchMap(url => Rx.Observable.fromPromise(getSearchResults(url)))
        .timeout(20000, new Error(`Timeout: ${url}`))
        .retry(3);

request("http://foobar.com").subscribe(console.log, console.error);

function getSearchResults(url) {
  // simulating request-error
  throw new Error("Could not reach: " + url);
}

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