How would you design a plugin or extensibility system in Go using interfaces?

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Accepted Answer

// Core plugin interface
type Plugin interface {
    Name() string
    Execute(ctx context.Context, payload []byte) ([]byte, error)
}

// Registry
type Registry struct {
    plugins map[string]Plugin
}

func NewRegistry() *Registry {
    return &Registry{plugins: make(map[string]Plugin)}
}

func (r *Registry) Register(p Plugin) {
    r.plugins[p.Name()] = p
}

func (r *Registry) Run(ctx context.Context, name string, payload []byte) ([]byte, error) {
    p, ok := r.plugins[name]
    if !ok {
        return nil, fmt.Errorf("plugin %q not found", name)
    }
    return p.Execute(ctx, payload)
}

// A plugin implementation
type JSONTransformPlugin struct{}
func (p *JSONTransformPlugin) Name() string { return "json-transform" }
func (p *JSONTransformPlugin) Execute(ctx context.Context, payload []byte) ([]byte, error) {
    // transform logic
    return payload, nil
}

// Registration at startup
func main() {
    r := NewRegistry()
    r.Register(&JSONTransformPlugin{})
} Compile-time plugins (interface slice + init registration) — simple, type-safe, no OS dependencies Go plugin package (.so files) — true runtime loading, but only works on Linux, requires same Go version, CGo limitations gRPC-based plugins — language-agnostic, process isolation, network overhead Functional options pattern for plugin configuration without breaking the interface Most production systems prefer compile-time or gRPC plugins over the native plugin package

How would you design a plugin or extensibility system in Go using interfaces?

Define a core Plugin interface, register implementations in a map, and use functional options for configuration. For runtime plugins consider Go's plugin package, though many teams prefer gRPC-based extension points.

How would you design a plugin or extensibility system in Go using interfaces?

Define a core Plugin interface, register implementations in a map, and use functional options for configuration. For runtime plugins consider Go's plugin package, though many teams prefer gRPC-based extension points.

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