Utility Function to Handle Errors: catchError

Mustafa DalgaMustafa Dalga
2 min read

Developing a utility function to handle errors is crucial for maintaining a clean codebase and providing meaningful feedback to users. The goal of this utility, catchError, is to streamline error handling, particularly for Axios requests, but also for general JavaScript errors. By centralizing the error-handling logic, we can ensure consistency across the application and simplify the error handling in individual catch blocks.

import { isAxiosError } from 'axios';

interface IAxiosError {
    message: string,
    status: number
}

export function catchError(error: any, defaultMessage: string = "An error occurred. Please try again later."): IAxiosError {
    if (isAxiosError(error)) {
        if (error.response) {
            const { data: { message }, status } = error.response;
            return {
                status,
                message: message || defaultMessage
            }
        }

        if (error.request) {
            return {
                status: -1,
                message: "No response from the server. Please check your internet connection."
            }
        }

        return {
            status: -2,
            message: "An unexpected error occurred while setting up the request."
        }
    }

    return {
        status: -3,
        message: error.message || defaultMessage
    }
}

Usage:

To use the catchError utility, simply call it within a catch block:

try {
    // Some code that might throw an error, e.g., an Axios request
} catch (error) {
    const { message, status } = catchError(error);
    console.error(`Error ${status}: ${message}`);
    // Handle the error, e.g., show a toast or alert with the message
}

Note:

The utility function assigns custom status codes to certain error scenarios:

  • -1: No server response (e.g., network issues).

  • -2: Axios-specific error not tied to server response.

  • -3: General JavaScript error not related to Axios.

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Written by

Mustafa Dalga
Mustafa Dalga

I am a highly qualified software developer with over 6 years of experience in developing desktop and web applications using various technologies.My main programming language is JavaScript, and I am currently working as a Front-end developer at Heybooster. I am passionate about software development and constantly seek to improve my skills and knowledge through research and self-teaching. I share my projects on Github as open source to not only learn and grow, but also contribute to the development community. As a software developer, I am committed to upholding ethical standards in my work.