Error Handling in Angular Applications

Angular applications, like any other software, may encounter errors while running. These errors can occur due to various reasons, including coding errors, user input errors, network errors, and server-side errors. Error handling is an essential part of Angular application development, as it helps ensure that the application is robust, reliable, and user-friendly.

Handling Errors in Angular Applications

In Angular, error handling involves two main aspects: detecting errors and responding to errors. Angular provides several tools and strategies for handling errors in the application.

Error Interceptors

Angular uses HTTP interceptors to intercept HTTP requests and responses to modify or transform them. Error interceptors are a type of HTTP interceptor that intercepts HTTP responses with error status codes (400 and above) and handles them appropriately.


import { Injectable } from ‘@angular/core’;
import { HttpInterceptor, HttpHandler, HttpRequest, HttpErrorResponse } from ‘@angular/common/http’;
import { catchError } from ‘rxjs/operators’;
import { throwError } from ‘rxjs’;

export class ErrorInterceptor implements HttpInterceptor {
intercept(request: HttpRequest, next: HttpHandler) {
return next.handle(request).pipe(
catchError((error: HttpErrorResponse) => {
let errorMessage = ”;
if (error.error instanceof ErrorEvent) {
// client-side error
errorMessage = `Error: ${error.error.message}`;
} else {
// server-side error
errorMessage = `Error Code: ${error.status}\nMessage: ${error.message}`;
return throwError(errorMessage);

In this example, the error interceptor catches any HTTP errors and logs the error message to the console. The `throwError` function returns an observable that emits the error message.

Global Error Handler

Angular provides a global error handler that catches all errors that occur in the application. This error handler is implemented by creating a service that implements the ErrorHandler interface.


import { ErrorHandler, Injectable } from ‘@angular/core’;

export class GlobalErrorHandler implements ErrorHandler {

handleError(error: any) {
// do something with the error
console.log(‘Global Error Handler’, error);


In this example, the global error handler logs any errors that occur in the application to the console.

Logging and Reporting Errors

Logging and reporting errors is a crucial aspect of error handling. Logging errors helps developers identify and debug issues in the application, while reporting errors to the server helps track and analyze errors in the production environment.

Angular provides several logging and reporting tools, including:

– Angular Logging Service
– Third-Party Logging Services (Sentry, LogRocket, etc.)
– Server-Side Error Tracking (such as Google Analytics)


What is the best way to handle errors in an Angular application?

The best way to handle errors in an Angular application is to implement a combination of error interceptors, global error handlers, and logging and reporting tools. The error interceptor catches HTTP errors, the global error handler catches all other errors, and the logging and reporting tools help track and debug errors.

How do I log errors in an Angular application?

Angular provides a built-in logging service called `console`. You can use the `console.log()` function to log errors to the console. Additionally, you can use third-party logging services or implement server-side error tracking to track errors in the production environment.

How do I report errors to the server in an Angular application?

You can report errors to the server by sending an HTTP request to the server with the error details. You can use the `HttpClient` service in Angular to send the HTTP request. Additionally, you can use server-side error tracking services such as Google Analytics to track and analyze errors in the production environment.

How can I test error handling in an Angular application?

You can test error handling in an Angular application by intentionally triggering errors in your code or by simulating errors in your test environment. You can use the `HttpClientTestingModule` in Angular to mock HTTP requests and responses and test error handling. Additionally, you can use tools such as Jasmine and Karma to write and run tests for your application.

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