如何在 angular 应用程序上显示来自 springboot 的异常消息

Question

I was working on spring boot + angular integration and I want to know how I can display exception message in my angular application. I have created exception handler class in spring boot something like this:

@ControllerAdvice
public class ExceptionController {

@ExceptionHandler(value={CommonException.class})
public ResponseEntity<Object> noResult(CommonException e){
    HttpStatus status=HttpStatus.BAD_REQUEST;       
    return new ResponseEntity<Object>(new CustomExceptionPayload(e.getMessage(),"400"), status);
}
}

and in angular side I am sending request through service class using httpclient like this:

public generatFile(file:any,to:string,from:string,proj_name:string,count:string,env:string,event:string){
    console.log("in service");
    const formData=new FormData();
    formData.append('file',file);
    formData.append('to',to);
    formData.append('from',from);
    formData.append('proj_name',proj_name);
    formData.append('event',event);
    formData.append('env',env);
    formData.append('count',count);

    return this.http.post(this.baseUrl+'/events',formData,{
        observe: 'response',
        responseType: 'blob' as 'json'
      }
    );
}

And in my main component receiving response like this:

this.service.generatFile(this.file,new Date(this.to).toLocaleDateString(),new Date(this.from).toLocaleDateString(),this.proj_name,this.count,this.env,this.event).subscribe((resp: any) => {
    const blob = new Blob([resp.body], { type: resp.headers.get('Content-Type') });
    saveAs(blob, this.fileName);
    this.loading=false;
  },((error:any) =>{
    this.message=error.message;
    this.loading=false;
  }

I was using error.message in angular to get the error message as given above but it didn't work.

When i use postman i get this as response:

{
"message": "number of events per file is greater than number of failed events",
"status": "400"
}

I don't know how to get same error message in angular which I'm sending from spring boot.I will appreciate if anyone can provide the answer with code.

Answer 1

You can use error object from observable.

this.service.generatFile().subscribe(
    (res) => {
        // handle response
    }, (err) => {
        // handle errors
    });