Router Deep Dive

Master all 29 handler forms and advanced routing patterns
Time: 60-75 minutes • Level: Advanced • Prerequisites: Essentials - Router

🎯 What You’ll Learn

• All 29 handler signatures and when to use each
• Handler lifecycle (before/after hooks)
• Advanced parameter binding
• Route priorities and conflict resolution
• Error handling strategies
• Performance optimizations

📚 Topics

1. All Handler Forms

Understanding all 29 handler signatures:

• Basic forms (void, error, response)
• Context forms (with *request.Context)
• Parameter forms (with path/query params)
• Combined forms (context + params + response)

2. Handler Selection Strategy

Learn when to use each handler form:

• Performance considerations
• Code clarity vs flexibility
• Error handling needs
• Response formatting requirements

3. Advanced Parameter Binding

Deep dive into parameter extraction:

• Path parameters
• Query parameters
• Header parameters
• Body binding
• Custom validators

4. Route Lifecycle

Master the handler lifecycle:

• Before hooks
• Main handler execution
• After hooks
• Error handling flow

5. Route Priorities

Understanding route matching:

• Exact matches vs patterns
• Parameter routes
• Wildcard routes
• Conflict resolution

6. Error Handling Patterns

Advanced error handling:

• Structured errors
• Error middleware
• Custom error responses
• Error recovery

7. Performance Optimization

Optimize your routes:

• Handler form selection impact
• Parameter binding overhead
• Response serialization
• Benchmarking techniques

8. Debugging and Testing

Debug complex routing:

• Route inspection
• Request tracing
• Unit testing handlers
• Integration testing

📂 Examples

All examples are in the examples/ folder:

01 - All Handler Forms

Demonstrates all 29 handler signatures with working examples.

02 - Parameter Binding

Advanced parameter extraction and validation.

03 - Lifecycle Hooks

Before/after hooks and middleware integration.

04 - Route Priorities

Understanding route matching and conflicts.

05 - Error Handling

Structured error handling patterns.

06 - Performance

Benchmarks and optimization techniques.

07 - Testing

Unit and integration testing strategies.

🚀 Quick Start

# Run any example
cd docs/02-deep-dive/01-router/examples/01-all-handler-forms
go run main.go

# Test with provided test.http
# (use VS Code REST Client extension)

📖 Prerequisites

Before diving in, make sure you understand:

• Basic routing
• Handler basics
• Parameter binding

🎯 Learning Path

1. Study all handler forms → Understand available options
2. Learn selection strategy → Choose the right form
3. Master parameters → Extract data efficiently
4. Understand lifecycle → Control execution flow
5. Handle errors → Build robust handlers
6. Optimize → Improve performance
7. Test → Ensure correctness

💡 Key Takeaways

After completing this section:

• ✅ You’ll know all 29 handler forms
• ✅ You’ll choose the right form for each use case
• ✅ You’ll handle complex parameter scenarios
• ✅ You’ll write testable, performant handlers
• ✅ You’ll debug routing issues effectively

Coming Soon - Examples and detailed content are being prepared.

Next: Service Deep Dive →