git-hardening/.crosslink/rules/go.md

Go Best Practices

Code Style

• Use gofmt for formatting
• Use golint and go vet for linting
• Follow effective Go guidelines
• Keep functions short and focused

Error Handling

// GOOD: Check and handle errors
func readConfig(path string) (*Config, error) {
    data, err := os.ReadFile(path)
    if err != nil {
        return nil, fmt.Errorf("reading config: %w", err)
    }

    var config Config
    if err := json.Unmarshal(data, &config); err != nil {
        return nil, fmt.Errorf("parsing config: %w", err)
    }
    return &config, nil
}

// BAD: Ignoring errors
func readConfig(path string) *Config {
    data, _ := os.ReadFile(path)  // Don't ignore errors
    var config Config
    json.Unmarshal(data, &config)
    return &config
}

Concurrency

• Use channels for communication between goroutines
• Use sync.WaitGroup for waiting on multiple goroutines
• Use context.Context for cancellation and timeouts
• Avoid shared mutable state; prefer message passing

Security

• Use html/template for HTML output (auto-escaping)
• Use parameterized queries for SQL
• Validate all input at API boundaries
• Use crypto/rand for secure random numbers