leverage global object creator in proxies.

proxy/context.go

@@ -0,0 +1,36 @@
+package proxy
+
+import (
+	"context"
+)
+
+type key int
+
+const (
+	inboundMetaKey  = key(0)
+	outboundMetaKey = key(1)
+)
+
+func ContextWithInboundMeta(ctx context.Context, meta *InboundHandlerMeta) context.Context {
+	return context.WithValue(ctx, inboundMetaKey, meta)
+}
+
+func InboundMetaFromContext(ctx context.Context) *InboundHandlerMeta {
+	v := ctx.Value(inboundMetaKey)
+	if v == nil {
+		return nil
+	}
+	return v.(*InboundHandlerMeta)
+}
+
+func ContextWithOutboundMeta(ctx context.Context, meta *OutboundHandlerMeta) context.Context {
+	return context.WithValue(ctx, outboundMetaKey, meta)
+}
+
+func OutboundMetaFromContext(ctx context.Context) *OutboundHandlerMeta {
+	v := ctx.Value(outboundMetaKey)
+	if v == nil {
+		return nil
+	}
+	return v.(*OutboundHandlerMeta)
+}