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
+}

pkg/server/provider/provider_test.go

@@ -0,0 +1,115 @@
+package provider
+
+import (
+	"context"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestAddProviderInContext(t *testing.T) {
+	testCases := []struct {
+		desc     string
+		ctx      context.Context
+		name     string
+		expected string
+	}{
+		{
+			desc:     "without provider information",
+			ctx:      context.Background(),
+			name:     "test",
+			expected: "",
+		},
+		{
+			desc:     "provider name embedded in element name",
+			ctx:      context.Background(),
+			name:     "test@foo",
+			expected: "foo",
+		},
+		{
+			desc:     "provider name in context",
+			ctx:      context.WithValue(context.Background(), key, "foo"),
+			name:     "test",
+			expected: "foo",
+		},
+		{
+			desc:     "provider name in context and different provider name embedded in element name",
+			ctx:      context.WithValue(context.Background(), key, "foo"),
+			name:     "test@fii",
+			expected: "fii",
+		},
+		{
+			desc:     "provider name in context and same provider name embedded in element name",
+			ctx:      context.WithValue(context.Background(), key, "foo"),
+			name:     "test@foo",
+			expected: "foo",
+		},
+	}
+
+	for _, test := range testCases {
+		test := test
+		t.Run(test.desc, func(t *testing.T) {
+			t.Parallel()
+
+			newCtx := AddInContext(test.ctx, test.name)
+
+			var providerName string
+			if name, ok := newCtx.Value(key).(string); ok {
+				providerName = name
+			}
+
+			assert.Equal(t, test.expected, providerName)
+		})
+	}
+}
+
+func TestGetQualifiedName(t *testing.T) {
+	testCases := []struct {
+		desc     string
+		ctx      context.Context
+		name     string
+		expected string
+	}{
+		{
+			desc:     "empty name",
+			ctx:      context.Background(),
+			name:     "",
+			expected: "",
+		},
+		{
+			desc:     "without provider",
+			ctx:      context.Background(),
+			name:     "test",
+			expected: "test",
+		},
+		{
+			desc:     "with explicit provider",
+			ctx:      context.Background(),
+			name:     "test@foo",
+			expected: "test@foo",
+		},
+		{
+			desc:     "with provider in context",
+			ctx:      context.WithValue(context.Background(), key, "foo"),
+			name:     "test",
+			expected: "test@foo",
+		},
+		{
+			desc:     "with provider in context and explicit name",
+			ctx:      context.WithValue(context.Background(), key, "foo"),
+			name:     "test@fii",
+			expected: "test@fii",
+		},
+	}
+
+	for _, test := range testCases {
+		test := test
+		t.Run(test.desc, func(t *testing.T) {
+			t.Parallel()
+
+			qualifiedName := GetQualifiedName(test.ctx, test.name)
+
+			assert.Equal(t, test.expected, qualifiedName)
+		})
+	}
+}