Overview

AxiosService is a utility class designed to encapsulate Axios HTTP requests with added features such as caching, request cancellation, token management, error handling, and performance monitoring. It aims to provide a robust and flexible HTTP service for modern JavaScript applications.

Features

1. Initialization and Configuration

   • Configures an Axios instance with default or custom settings including base URL, headers, timeout, caching, retry logic, and token management.

2. Global Error Handling

   • Listens for unhandled promise rejections and general errors in the window context, logging errors to the console.

3. Performance Monitoring

   • Intercepts requests to log their start and end times, calculating request durations for performance monitoring.

4. Request Cancellation

   • Intercepts requests to enable cancellation using Axios cancel tokens.
   • Tracks ongoing requests to manage and cancel duplicate requests if required.

5. Token Management

   • Manages authentication tokens, automatically refreshing expired tokens using a provided refresh token URL.
   • Checks token expiration and refreshes tokens as needed to maintain API access.

6. HTTP Methods

   • Provides wrapper methods for common Axios HTTP methods (GET, POST, PUT, DELETE) with added functionalities such as caching responses and uniform error handling.

7. Error Handling

   • Centralized error handling for Axios requests, including automatic retry on token refresh (401 Unauthorized error).

8. Instance Creation

   • Static method createInstance() allows creating instances of AxiosService with custom configurations.

Usage Example

import AxiosService from './AxiosService';

// Create an instance of AxiosService with custom configurations
const axiosInstance = AxiosService.createInstance({
  baseURL: 'https://api.example.com',
  headers: {
    'X-Custom-Header': 'foobar',
  },
  cacheEnabled: true,
  retry: true,
  tokenRefreshEnabled: true,
});

// Example GET request
axiosInstance.get('/data', { params: { key: 'value' } })
  .then(data => {
    console.log('Response:', data);
  })
  .catch(error => {
    console.error('Request failed:', error);
  });

Methods

Constructor

constructor(config = {})

• Initializes the AxiosService instance with default and custom configuration options.
• Configures Axios instance, caching, retry logic, token management, and other features based on provided settings.

Instance Methods

async refreshToken()

• Attempts to refresh the authentication token using a specified refresh token URL.
• Updates token and tokenExpiration upon successful token refresh.

async getToken()

• Retrieves the current authentication token.
• Refreshes the token if expired or not available.

isTokenExpired()

• Checks if the current authentication token is expired.

async get(url, params = {}, config = {})

• Performs a GET request to the specified URL with optional parameters and configuration.
• Implements caching of responses if enabled.

async post(url, data, config = {})

• Performs a POST request to the specified URL with data and optional configuration.

async put(url, data, config = {})

• Performs a PUT request to the specified URL with data and optional configuration.

async delete(url, config = {})

• Performs a DELETE request to the specified URL with optional configuration.

handleSuccess(response)

• Handles successful HTTP responses, extracting and returning response data.

handleError(error)

• Centralized error handling for Axios requests.
• Automatically retries requests upon token refresh if 401 Unauthorized error occurs.
• Logs specific error details including status codes and response data.

Static Method

static createInstance(config = {})

• Creates a new instance of AxiosService with custom configuration options.
• Returns the initialized instance ready for HTTP requests.

Error Handling

• Handles various HTTP errors including 401 Unauthorized for automatic token refresh.
• Logs detailed error information for debugging and monitoring purposes.

Security Considerations

• Secure handling of authentication tokens and sensitive data such as refresh tokens.
• Usage of secure storage or environment variables for sensitive configurations.

Performance Monitoring

• Logs request durations to monitor API performance and response times.

Request Cancellation

• Supports cancellation of ongoing requests to prevent redundant API calls.
• Manages Axios cancel tokens to handle request cancellation efficiently.

Dependencies

• Requires axios for HTTP requests and node-cache for caching (optional).

Example Use Cases

• Building robust API clients for frontend applications.
• Integrating with RESTful APIs that require token-based authentication.
• Managing and monitoring API performance and error handling in JavaScript applications.