feat: initial commit

internal/proxy/director/context.go

@@ -0,0 +1,60 @@
+package director
+
+import (
+	"context"
+
+	"forge.cadoles.com/cadoles/bouncer/internal/store"
+	"github.com/pkg/errors"
+)
+
+type contextKey string
+
+const (
+	contextKeyProxy  contextKey = "proxy"
+	contextKeyLayers contextKey = "layers"
+)
+
+var (
+	errContextKeyNotFound     = errors.New("context key not found")
+	errUnexpectedContextValue = errors.New("unexpected context value")
+)
+
+func withProxy(ctx context.Context, proxy *store.Proxy) context.Context {
+	return context.WithValue(ctx, contextKeyProxy, proxy)
+}
+
+func ctxProxy(ctx context.Context) (*store.Proxy, error) {
+	proxy, err := ctxValue[*store.Proxy](ctx, contextKeyProxy)
+	if err != nil {
+		return nil, errors.WithStack(err)
+	}
+
+	return proxy, nil
+}
+
+func withLayers(ctx context.Context, layers []*store.Layer) context.Context {
+	return context.WithValue(ctx, contextKeyLayers, layers)
+}
+
+func ctxLayers(ctx context.Context) ([]*store.Layer, error) {
+	layers, err := ctxValue[[]*store.Layer](ctx, contextKeyLayers)
+	if err != nil {
+		return nil, errors.WithStack(err)
+	}
+
+	return layers, nil
+}
+
+func ctxValue[T any](ctx context.Context, key contextKey) (T, error) {
+	raw := ctx.Value(key)
+	if raw == nil {
+		return *new(T), errors.WithStack(errContextKeyNotFound)
+	}
+
+	value, ok := raw.(T)
+	if !ok {
+		return *new(T), errors.WithStack(errUnexpectedContextValue)
+	}
+
+	return value, nil
+}