Typescript Error Handling

Typescript error handling

Created By: chatGPT

In TypeScript, effective error handling is crucial for maintaining robust applications. TypeScript enhances JavaScript by providing static typing, which helps catch many errors at compile time. However, handling errors at runtime is still essential. The try-catch mechanism is a common way to manage exceptions. Below is an example of how to implement it.

try {
    // Code that may throw an error
    const result = someFunction();
} catch (error) {
    // Handle the error
    console.error('Error occurred:', error);
}

Sometimes, you may want to handle specific types of errors differently. For instance, you may want to differentiate between a network error and a validation error. You can use instanceof to check the type of error.

try {
    await fetchData();
} catch (error) {
    if (error instanceof NetworkError) {
        console.error('Network error:', error);
    } else if (error instanceof ValidationError) {
        console.error('Validation error:', error);
    } else {
        console.error('General error:', error);
    }
}

In a Node.js environment, you can also utilize the async/await syntax for asynchronous operations. Combining try-catch with async functions provides a clean way to handle errors.

async function fetchData() {
    try {
        const response = await fetch('https://api.example.com/data');
        const data = await response.json();
        return data;
    } catch (error) {
        console.error('Fetch error:', error);
        throw error; // Optionally re-throw the error
    }
}

For more structured error handling, you can create custom error classes. This allows you to define specific properties and methods for different error types, which can make your error handling more meaningful.

class CustomError extends Error {
    constructor(message) {
        super(message);
        this.name = 'CustomError';
        this.timestamp = new Date();
    }
}

throw new CustomError('Something went wrong!');

Lastly, in a production application, using logging libraries can greatly enhance your error handling strategy. Libraries like winston or bunyan provide options for logging errors to files or external services, which helps in monitoring and diagnosing issues.

import { createLogger, format, transports } from 'winston';

const logger = createLogger({
    level: 'error',
    format: format.combine(
        format.timestamp(),
        format.json()
    ),
    transports: [
        new transports.Console(),
        new transports.File({ filename: 'error.log' })
    ],
});

logger.error('Error message', { error });