React & Apis Interview Questions

Common methods include fetch API, Axios, React Query, SWR, GraphQL clients. Each has different features for handling requests, caching, error handling, and request cancellation.

Use useEffect for API calls, handle cleanup with cancel tokens, manage loading and error states, implement proper dependency array. Consider race conditions and component unmounting.

React Query is a data-fetching library that provides caching, background updates, pagination, and optimistic updates. Solves common issues like cache management, loading states, and server state synchronization.

Use try-catch blocks, implement error boundaries, handle different error types, provide user feedback. Consider retry mechanisms and graceful degradation.

Implement proper loading states, handle error cases, manage cache invalidation, consider optimistic updates. Use appropriate state management solutions for API data.

Manage tokens securely, handle token refresh, implement interceptors for requests, manage auth state. Consider session management and security implications.

SWR is a React Hooks library for data fetching that implements stale-while-revalidate strategy. Provides automatic revalidation, focus tracking, and interval polling features.

Use caching libraries (React Query, SWR), implement local storage caching, handle cache invalidation, manage cache lifecycle. Consider cache strategies and freshness.

Implement WebSocket connections, handle Socket.IO integration, manage real-time state updates, handle connection states. Consider reconnection strategies and data consistency.

Handle page state, implement infinite scroll or pagination controls, manage loading states, cache paginated data. Consider optimization and user experience.

Implement request debouncing/throttling, batch requests when possible, optimize payload size, use proper caching strategies. Consider performance and bandwidth usage.

Use FormData, handle upload progress, implement chunk uploads for large files, manage upload states. Consider validation and error handling.

Implement service workers, handle offline storage, manage sync queues, handle conflict resolution. Consider offline-first architecture and data synchronization.

Update UI immediately before API confirmation, handle rollback on failure, manage temporary state, implement proper error recovery. Consider user experience and data consistency.

Implement retry mechanisms, handle different error types appropriately, provide fallback content, manage error states. Consider user feedback and recovery options.

Use AbortController, implement cleanup in useEffect, handle cancel tokens with axios, manage pending requests. Consider race conditions and component lifecycle.

Implement request queuing, handle rate limit errors, manage retry strategies, provide user feedback. Consider backend limitations and optimization strategies.

Use MSW (Mock Service Worker), implement mock data, handle different scenarios, manage mock configurations. Consider testing and development workflow.

Implement proper authentication/authorization, handle CORS, prevent XSS attacks, manage sensitive data. Consider security best practices and vulnerabilities.

Manage API version in configurations, handle version-specific logic, implement proper abstractions. Consider backward compatibility and maintenance.

Implement data normalization, handle response mapping, manage data transformation logic. Consider consistency and maintainability.

Handle sequential requests, manage request priority, implement queue processing logic. Consider error handling and queue management.

Track request times, monitor error rates, implement performance metrics, analyze bottlenecks. Consider monitoring tools and optimization strategies.

Implement exponential backoff, handle retry limits, manage retry states, provide feedback. Consider error types and retry strategies.

Use Apollo Client or other GraphQL clients, manage queries and mutations, handle caching, implement proper error handling. Consider GraphQL-specific optimizations.

Handle authentication headers, manage custom headers, implement interceptors, handle dynamic headers. Consider security and configuration management.

Implement unit tests for API integration, mock API responses, test error scenarios, verify data handling. Consider test coverage and maintenance.

Implement request combining, manage batch processing, handle response correlation, optimize network usage. Consider performance and complexity trade-offs.

Implement local storage caching, handle state rehydration, manage persistence lifecycle. Consider storage strategies and state management.

Handle request/response logging, implement debugging tools, manage log levels, track API usage. Consider privacy and performance implications.