Javascript Examples

Implement JWT authentication flow in Node.js Express with bcrypt password hashing, token signing and verification, refresh token endpoint, and protected.

Build an interactive CLI tool in Node.js using Inquirer for prompts, chalk for colored output, and ora for spinners. Includes command chaining, template.

Handle file uploads in Node.js Express using multer middleware with disk and memory storage strategies, file filtering by MIME type, size limits, and.

Validate form data in Node.js Express using express-validator middleware chains, custom sanitizers, grouped error responses, and conditional validation.

Implement a cached fetch wrapper in vanilla JavaScript using the Cache API with stale-while-revalidate strategy, request deduplication, and automatic cache.

Implement JWT authentication in vanilla JavaScript with token storage in localStorage, automatic token attachment to fetch requests, expiry checking, and.

Build a command-line utility in vanilla JavaScript using process.argv parsing, readline for interactive prompts, chalk-free colored output with ANSI codes,.

Fetch and render remote data with vanilla JavaScript using async/await, AbortController for cancellation, loading state management, and error handling with.

Upload files with vanilla JavaScript using XMLHttpRequest for progress tracking, drag-and-drop support, file type validation, and chunked upload for large.

Validate HTML forms with vanilla JavaScript using the Constraint Validation API. Provides custom error messages, real-time validation on input, and.

Build a file upload component in Vue 3 with drag-and-drop, progress bar, multiple file support, preview thumbnails for images, and automatic upload with.

Fetch data in Vue 3 using composables with reactive loading states, error handling, automatic refetch on parameter change, and cleanup on component unmount.

Build reactive forms in Vue 3 using the Composition API with ref and computed. Includes two-way binding, validation rules, dynamic field generation, and.