Troubleshooting the canLoad problem caused by returning an observable with a 404 error

Question

Troubleshooting the canLoad problem caused by returning an observable with a 404 error

I have implemented a check to call an API in the canLoad event for a module in my Angular application.

However, even if the API returns a 404 error in the network, my page continues to load. I want to change this behavior so that if a 404 error is encountered, the page should redirect to an error page.

canLoad(route: Route, segments: UrlSegment[]) 
{
       return this.http.get('testapi/getacces').pipe(map((response: boolean) => {
           if (response) {
               return true;
           } else {
               this.router.navigate(['/error']);
               return false;
           }
       }));
   }

While the code works as expected when the API is available, it does not handle the situation where a 404 error occurs. I am looking for a solution to properly handle the exception and route to an error page in case of a 404 error.

javascript rxjs angular7 canactivate angular-canload

Answer 1

Answer №1

Utilize the catchError() operator to effectively manage error scenarios rather than successful responses.

Here's an example:

  canLoad(route: Route, segments: UrlSegment[]) {
    return this.http.get('testapi/getacces').pipe(
      map((response: boolean) => {
        if (response) {
          return true;
        } else {
          this.router.navigate(['/error']);
          return false;
        }
      }),
      catchError((error) =>
        of(error).pipe(
          map(() => {
            this.router.navigate(['/error']);
            return false;
          }),
        ),
      ),
    );
  }

This approach is helpful because a 404 Error response will not be caught by map, but it will trigger catchError, allowing you to handle Error responses accordingly.

Answer 2

Utilize the catchError() operator to effectively manage error scenarios rather than successful responses.

Here's an example:

  canLoad(route: Route, segments: UrlSegment[]) {
    return this.http.get('testapi/getacces').pipe(
      map((response: boolean) => {
        if (response) {
          return true;
        } else {
          this.router.navigate(['/error']);
          return false;
        }
      }),
      catchError((error) =>
        of(error).pipe(
          map(() => {
            this.router.navigate(['/error']);
            return false;
          }),
        ),
      ),
    );
  }

This approach is helpful because a 404 Error response will not be caught by map, but it will trigger catchError, allowing you to handle Error responses accordingly.

Troubleshooting the canLoad problem caused by returning an observable with a 404 error

Answer №1

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