Go API Development with Standard Library

Core Principles

• •Always use the latest stable version of Go (1.22 or newer) and be familiar with RESTful API design principles, net/http package, and the new ServeMux introduced in Go 1.22
• •Follow the user's requirements carefully and to the letter
• •First think step-by-step - describe your plan for the API structure, endpoints, and data flow in pseudocode, written out in great detail
• •Write correct, up-to-date, bug-free, fully functional, secure, and efficient Go code for APIs
• •Leave NO todos, placeholders, or missing pieces in the API implementation
• •Always prioritize security, scalability, and maintainability in your API designs

API Development Guidelines

Routing and HTTP Handling

• •Use the new http.ServeMux introduced in Go 1.22 for routing
• •Implement proper HTTP method handling (GET, POST, PUT, DELETE, PATCH)
• •Use appropriate HTTP status codes for responses
• •Implement proper content-type handling for requests and responses

Error Handling

• •Implement proper error handling, including custom error types when beneficial
• •Return appropriate HTTP status codes with error responses
• •Use structured error responses in JSON format
• •Log errors appropriately for debugging and monitoring

Input Validation

• •Implement input validation for API endpoints
• •Validate request bodies, query parameters, and path parameters
• •Return clear validation error messages to clients
• •Sanitize inputs to prevent injection attacks

JSON Handling

• •Use encoding/json for JSON serialization/deserialization
• •Implement proper struct tags for JSON field mapping
• •Handle JSON parsing errors gracefully
• •Use appropriate JSON formatting for responses

Concurrency

• •Leverage Go's built-in concurrency features when appropriate for API performance
• •Use goroutines for concurrent operations where beneficial
• •Implement proper synchronization for shared state
• •Use context for request cancellation and timeouts

Middleware

• •Implement middleware for cross-cutting concerns (logging, authentication, rate limiting)
• •Use middleware chaining for composable request processing
• •Implement CORS handling where needed
• •Add request/response logging middleware

Security

• •Implement authentication and authorization where appropriate
• •Use HTTPS in production
• •Implement rate limiting to prevent abuse
• •Validate and sanitize all user inputs
• •Use secure defaults for cookies and sessions

Logging

• •Use standard library logging with structured output
• •Log appropriate information for debugging and monitoring
• •Avoid logging sensitive information
• •Use log levels appropriately

Testing

• •Write unit tests for handlers and business logic
• •Implement integration tests for API endpoints
• •Use table-driven tests where appropriate
• •Mock external dependencies in tests