use provider-qualified name when recursing for chain

pkg/server/provider/provider.go

@@ -0,0 +1,45 @@
+package provider
+
+import (
+	"context"
+	"strings"
+
+	"github.com/containous/traefik/v2/pkg/log"
+)
+
+type contextKey int
+
+const (
+	key contextKey = iota
+)
+
+// AddInContext Adds the provider name in the context
+func AddInContext(ctx context.Context, elementName string) context.Context {
+	parts := strings.Split(elementName, "@")
+	if len(parts) == 1 {
+		log.FromContext(ctx).Debugf("Could not find a provider for %s.", elementName)
+		return ctx
+	}
+
+	if name, ok := ctx.Value(key).(string); ok && name == parts[1] {
+		return ctx
+	}
+
+	return context.WithValue(ctx, key, parts[1])
+}
+
+// GetQualifiedName Gets the fully qualified name.
+func GetQualifiedName(ctx context.Context, elementName string) string {
+	parts := strings.Split(elementName, "@")
+	if len(parts) == 1 {
+		if providerName, ok := ctx.Value(key).(string); ok {
+			return MakeQualifiedName(providerName, parts[0])
+		}
+	}
+	return elementName
+}
+
+// MakeQualifiedName Creates a qualified name for an element
+func MakeQualifiedName(providerName string, elementName string) string {
+	return elementName + "@" + providerName
+}