Perform Http get method in Angular with no retries and wait until server sends the response?

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猫巷女王i
猫巷女王i 2020-12-20 07:55

I have the following in my controller, in a Spring-Boot application:

@RequestMapping(method=RequestMethod.GET,value=\"/info\")
public DataModel getinfodata()         


        
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  •  谎友^
    谎友^ (楼主)
    2020-12-20 08:42

    The http observable makes an http request for each subscriber. So the 3 to 4 http request means you must have multiple components subscribing at the same time. To share a single http request for multiple observers, you need something like the share operator.

    export class FetchService {
        data$: Observable;
    
        constructor(){
            this.data$ = this._http.request(this._url)
                .map((res:Response)=>res.json())
                .catch(this.errorHandler)
                .share();
        }
    
        getData(){
            return this.data$;
        }
    }
    

    Now the multiple observers will share the same observable.

    This operator is a specialization of publish which creates a subscription when the number of observers goes from zero to one, then shares that subscription with all subsequent observers until the number of observers returns to zero, at which point the subscription is disposed.


    As for your ERR_EMPTY_RESPONSE issue. I've run into this when my proxied api call timesout.

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