swarm: codebase split from go-ethereum (#1405)

sctx/sctx.go

@@ -0,0 +1,37 @@
+package sctx
+
+import "context"
+
+type (
+	HTTPRequestIDKey struct{}
+	requestHostKey   struct{}
+	tagKey           struct{}
+)
+
+// SetHost sets the http request host in the context
+func SetHost(ctx context.Context, domain string) context.Context {
+	return context.WithValue(ctx, requestHostKey{}, domain)
+}
+
+// GetHost gets the request host from the context
+func GetHost(ctx context.Context) string {
+	v, ok := ctx.Value(requestHostKey{}).(string)
+	if ok {
+		return v
+	}
+	return ""
+}
+
+// SetTag sets the tag unique identifier in the context
+func SetTag(ctx context.Context, tagId uint32) context.Context {
+	return context.WithValue(ctx, tagKey{}, tagId)
+}
+
+// GetTag gets the tag unique identifier from the context
+func GetTag(ctx context.Context) uint32 {
+	v, ok := ctx.Value(tagKey{}).(uint32)
+	if ok {
+		return v
+	}
+	return 0
+}