Angular http client observable pipe map
12,153
Try using this :
doSomething(): Observable<any> {
return this.http.get('http://my.api.com/something')
.pipe(
mergeMap((data: Response) => {
return of(data && data['success'] === true)
}
));
}
You have to perform the mergeMap first to do the check as your observable result will not be available if not...
Comments
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fransyozef almost 2 years
I have this in my service
doSomething(): Observable<any> { return this.http.get('http://my.api.com/something') .pipe( map((data: Response) => { if (data && data['success'] && data['success'] === true) { return true; } else { return false; } } ) ); }
This works, I can subscribe to the function from my component , for example
this.myService.doSomething().subscribe( (result) => { console.log(result); }, (err) => { console.log("ERROR!!!"); } );
Al this already works, but I want to refactor so that I can remove
if (data && data['success'] && data['success'] === true)
in my map. So that the map function only will be executed when I have upfront did the check. My first thought was to add a function in the pipe stack that will take the Response from the http client, check if the the conditions are good, otherwise throw an error (with throwError function). But I'm strugglin how to (well at least figure out wich Rxjs function to use).
Can somebody help me out with this?
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fransyozef over 5 yearsAh cewl .. I will try it. If this works, then I can create some reusable helpers.
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fransyozef over 5 yearsYes .. it worked , I have a helper export function checkServerSuccessResponse(data: Response): Observable<any> { return (data && data['success'] === true) ? of(data) : throwError("server responded false"); } so when the first condition is false, it will throw an error. if the condition is true, the data object is passed to the normal map