bouncer/internal/proxy/director/layer_registry.go

package director

import (
	"forge.cadoles.com/Cadoles/go-proxy"
	"forge.cadoles.com/cadoles/bouncer/internal/store"
)

type Layer interface {
	LayerType() store.LayerType
}

type MiddlewareLayer interface {
	Layer
	Middleware(layer *store.Layer) proxy.Middleware
}

type RequestTransformerLayer interface {
	Layer
	RequestTransformer(layer *store.Layer) proxy.RequestTransformer
}

type ResponseTransformerLayer interface {
	Layer
	ResponseTransformer(layer *store.Layer) proxy.ResponseTransformer
}

type LayerRegistry struct {
	index map[store.LayerType]Layer
}

func (r *LayerRegistry) GetLayer(layerType store.LayerType) (Layer, bool) {
	layer, exists := r.index[layerType]
	if !exists {
		return nil, false
	}

	return layer, true
}

func (r *LayerRegistry) getLayerAsAny(layerType store.LayerType) (any, bool) {
	return r.GetLayer(layerType)
}

func (r *LayerRegistry) GetMiddleware(layerType store.LayerType) (MiddlewareLayer, bool) {
	layer, exists := r.getLayerAsAny(layerType)
	if !exists {
		return nil, false
	}

	middleware, ok := layer.(MiddlewareLayer)
	if !ok {
		return nil, false
	}

	return middleware, true
}

func (r *LayerRegistry) GetResponseTransformer(layerType store.LayerType) (ResponseTransformerLayer, bool) {
	layer, exists := r.getLayerAsAny(layerType)
	if !exists {
		return nil, false
	}

	transformer, ok := layer.(ResponseTransformerLayer)
	if !ok {
		return nil, false
	}

	return transformer, true
}

func (r *LayerRegistry) GetRequestTransformer(layerType store.LayerType) (RequestTransformerLayer, bool) {
	layer, exists := r.getLayerAsAny(layerType)
	if !exists {
		return nil, false
	}

	transformer, ok := layer.(RequestTransformerLayer)
	if !ok {
		return nil, false
	}

	return transformer, true
}

func (r *LayerRegistry) Load(layers ...Layer) {
	index := make(map[store.LayerType]Layer)

	for _, l := range layers {
		layerType := l.LayerType()
		index[layerType] = l
	}

	r.index = index
}

func NewLayerRegistry(layers ...Layer) *LayerRegistry {
	registry := &LayerRegistry{
		index: make(map[store.LayerType]Layer),
	}
	registry.Load(layers...)

	return registry
}