bugfix: Fix mapping of enums to feature IDs

lib/gcpspanner/browser_feature_support_event.go

@@ -101,6 +101,8 @@ func calculateBrowserSupportEvents(
 // PrecalculateBrowserFeatureSupportEvents populates the BrowserFeatureSupportEvents table with pre-calculated data.
 func (c *Client) PrecalculateBrowserFeatureSupportEvents(ctx context.Context, startAt, endAt time.Time) error {
 	txn := c.ReadOnlyTransaction()
+	defer txn.Close()
+
 	// 1. Fetch all BrowserFeatureAvailabilities
 	availabilities, err := c.fetchAllBrowserAvailabilitiesWithTransaction(ctx, txn)
 	if err != nil {

lib/gcpspanner/spanneradapters/chromium_historgram_enum_consumer.go

@@ -19,10 +19,11 @@ import (
 	"errors"
 	"log/slog"
 	"strings"
-	"unicode"
 
 	"github.com/GoogleChrome/webstatus.dev/lib/gcpspanner"
 	"github.com/GoogleChrome/webstatus.dev/lib/metricdatatypes"
+	"golang.org/x/text/cases"
+	"golang.org/x/text/language"
 )
 
 // ChromiumHistogramEnumConsumer handles the conversion of histogram between the workflow/API input
@@ -43,10 +44,20 @@ type ChromiumHistogramEnumsClient interface {
 	UpsertChromiumHistogramEnumValue(context.Context, gcpspanner.ChromiumHistogramEnumValue) (*string, error)
 	UpsertWebFeatureChromiumHistogramEnumValue(context.Context, gcpspanner.WebFeatureChromiumHistogramEnumValue) error
 	GetIDFromFeatureKey(context.Context, *gcpspanner.FeatureIDFilter) (*string, error)
+	FetchAllFeatureKeys(context.Context) ([]string, error)
 }
 
+// Used by GCP Log-based metrics to extract the data about mismatch mappings.
+const logMissingFeatureIDMetricMsg = "unable to find feature ID. skipping mapping"
+
 func (c *ChromiumHistogramEnumConsumer) SaveHistogramEnums(
 	ctx context.Context, data metricdatatypes.HistogramMapping) error {
+	featureKeys, err := c.client.FetchAllFeatureKeys(ctx)
+	if err != nil {
+		return errors.Join(ErrFailedToGetFeatureKeys, err)
+	}
+	enumToFeatureKeyMap := createEnumToFeatureKeyMap(featureKeys)
+	// Create mapping of anticipated enums to feature keys
 	for histogram, enums := range data {
 		enumID, err := c.client.UpsertChromiumHistogramEnum(ctx, gcpspanner.ChromiumHistogramEnum{
 			HistogramName: string(histogram),
@@ -63,12 +74,21 @@ func (c *ChromiumHistogramEnumConsumer) SaveHistogramEnums(
 			if err != nil {
 				return errors.Join(ErrFailedToStoreEnumValue, err)
 			}
-			featureKey := enumLabelToFeatureKey(enum.Label)
+
+			featureKey, found := enumToFeatureKeyMap[enum.Label]
+			if !found {
+				slog.WarnContext(ctx,
+					logMissingFeatureIDMetricMsg,
+					"label", enum.Label)
+
+				continue
+			}
+
 			featureID, err := c.client.GetIDFromFeatureKey(
 				ctx, gcpspanner.NewFeatureKeyFilter(featureKey))
 			if err != nil {
 				slog.WarnContext(ctx,
-					"unable to find feature ID. skipping mapping",
+					logMissingFeatureIDMetricMsg,
 					"error", err,
 					"featureKey", featureKey,
 					"label", enum.Label)
@@ -97,29 +117,35 @@ var (
 	// the mapping between enum value and web feature.
 	ErrFailedToStoreEnumValueWebFeatureMapping = errors.New(
 		"failed to store web feature to chromium enum value mapping")
+	// ErrFailedToGetFeatureKeys indicates an internal error when trying to get all the feature keys.
+	ErrFailedToGetFeatureKeys = errors.New("failed to get feature keys")
 )
 
-func enumLabelToFeatureKey(label string) string {
-	b := strings.Builder{}
-	for idx, c := range label {
-		// First character just return the lower case version of it.
-		if idx == 0 {
-			b.WriteRune(unicode.ToLower(c))
+// nolint:lll // WONTFIX: useful comment message
+// createEnumToFeatureKeyMap uses the list of WebDX feature keys to
+// generate a map from the enum label (e.g., "ViewTransitions")
+// back to its original WebDX feature key (e.g., "view-transitions").
+// It uses the same transformation logic described in the Chromium mojom file.
+// https://source.chromium.org/chromium/chromium/src/+/main:third_party/blink/public/mojom/use_counter/metrics/webdx_feature.mojom;l=35-47;drc=822a70f9ac61a75babe9d24ddfc32ab475acc7e1
+func createEnumToFeatureKeyMap(featureKeys []string) map[string]string {
+	titleCaser := cases.Title(language.English)
+	m := make(map[string]string, len(featureKeys))
+	specialCases := map[string]string{
+		"float16array":          "Float16Array",
+		"uint8array-base64-hex": "Uint8ArrayBase64Hex",
+	}
+	for _, featureKey := range featureKeys {
+		if specialCaseLabel, found := specialCases[featureKey]; found {
+			m[specialCaseLabel] = featureKey
 
 			continue
 		}
-		if unicode.IsUpper(c) {
-			b.WriteRune('-')
-			b.WriteRune(unicode.ToLower(c))
 
-			continue
-		}
-		// Add hyphen if previous character is a letter and current character is a digit
-		if idx > 0 && unicode.IsLetter(rune(label[idx-1])) && unicode.IsDigit(c) {
-			b.WriteRune('-')
-		}
-		b.WriteRune(c)
+		enumLabel := titleCaser.String(featureKey)
+		enumLabel = strings.ReplaceAll(enumLabel, "-", "")
+		// Before storing it, check if it exists
+		m[enumLabel] = featureKey
 	}
 
-	return b.String()
+	return m
 }

lib/gcpspanner/spanneradapters/chromium_historgram_enum_consumer_test.go

@@ -17,6 +17,7 @@ package spanneradapters
 import (
 	"context"
 	"errors"
+	"reflect"
 	"testing"
 
 	"github.com/GoogleChrome/webstatus.dev/lib/gcpspanner"
@@ -31,6 +32,7 @@ type mockChromiumHistogramEnumsClient struct {
 	upsertWebFeatureChromiumHistogramEnumValue func(context.Context,
 		gcpspanner.WebFeatureChromiumHistogramEnumValue) error
 	getIDFromFeatureKey func(context.Context, *gcpspanner.FeatureIDFilter) (*string, error)
+	fetchAllFeatureKeys func(context.Context) ([]string, error)
 }
 
 func (m *mockChromiumHistogramEnumsClient) UpsertChromiumHistogramEnum(ctx context.Context,
@@ -53,6 +55,11 @@ func (m *mockChromiumHistogramEnumsClient) GetIDFromFeatureKey(ctx context.Conte
 	return m.getIDFromFeatureKey(ctx, in)
 }
 
+func (m *mockChromiumHistogramEnumsClient) FetchAllFeatureKeys(
+	ctx context.Context) ([]string, error) {
+	return m.fetchAllFeatureKeys(ctx)
+}
+
 func TestChromiumHistogramEnumConsumer_SaveHistogramEnums(t *testing.T) {
 	tests := []struct {
 		name        string
@@ -63,6 +70,9 @@ func TestChromiumHistogramEnumConsumer_SaveHistogramEnums(t *testing.T) {
 		{
 			name: "Success",
 			client: &mockChromiumHistogramEnumsClient{
+				fetchAllFeatureKeys: func(_ context.Context) ([]string, error) {
+					return []string{"enum-label"}, nil
+				},
 				upsertChromiumHistogramEnum: func(_ context.Context,
 					_ gcpspanner.ChromiumHistogramEnum) (*string, error) {
 					return valuePtr("enumID"), nil
@@ -87,9 +97,30 @@ func TestChromiumHistogramEnumConsumer_SaveHistogramEnums(t *testing.T) {
 			},
 			expectedErr: nil,
 		},
+		{
+			name: "FetchAllFeatureKeys returns error",
+			client: &mockChromiumHistogramEnumsClient{
+				fetchAllFeatureKeys: func(_ context.Context) ([]string, error) {
+					return nil, errors.New("test error")
+				},
+				upsertChromiumHistogramEnum:                nil,
+				upsertChromiumHistogramEnumValue:           nil,
+				upsertWebFeatureChromiumHistogramEnumValue: nil,
+				getIDFromFeatureKey:                        nil,
+			},
+			data: metricdatatypes.HistogramMapping{
+				metricdatatypes.WebDXFeatureEnum: []metricdatatypes.HistogramEnumValue{
+					{Value: 1, Label: "EnumLabel"},
+				},
+			},
+			expectedErr: ErrFailedToGetFeatureKeys,
+		},
 		{
 			name: "UpsertChromiumHistogramEnum returns error",
 			client: &mockChromiumHistogramEnumsClient{
+				fetchAllFeatureKeys: func(_ context.Context) ([]string, error) {
+					return []string{"enum-label"}, nil
+				},
 				upsertChromiumHistogramEnum: func(_ context.Context,
 					_ gcpspanner.ChromiumHistogramEnum) (*string, error) {
 					return nil, errors.New("test error")
@@ -108,6 +139,9 @@ func TestChromiumHistogramEnumConsumer_SaveHistogramEnums(t *testing.T) {
 		{
 			name: "UpsertChromiumHistogramEnumValue returns error",
 			client: &mockChromiumHistogramEnumsClient{
+				fetchAllFeatureKeys: func(_ context.Context) ([]string, error) {
+					return []string{"enum-label"}, nil
+				},
 				upsertChromiumHistogramEnum: func(_ context.Context,
 					_ gcpspanner.ChromiumHistogramEnum) (*string, error) {
 					return valuePtr("enumID"), nil
@@ -129,6 +163,9 @@ func TestChromiumHistogramEnumConsumer_SaveHistogramEnums(t *testing.T) {
 		{
 			name: "GetIDFromFeatureKey returns error",
 			client: &mockChromiumHistogramEnumsClient{
+				fetchAllFeatureKeys: func(_ context.Context) ([]string, error) {
+					return []string{"enum-label"}, nil
+				},
 				upsertChromiumHistogramEnum: func(_ context.Context,
 					_ gcpspanner.ChromiumHistogramEnum) (*string, error) {
 					return valuePtr("enumID"), nil
@@ -153,6 +190,9 @@ func TestChromiumHistogramEnumConsumer_SaveHistogramEnums(t *testing.T) {
 		{
 			name: "UpsertWebFeatureChromiumHistogramEnumValue returns error",
 			client: &mockChromiumHistogramEnumsClient{
+				fetchAllFeatureKeys: func(_ context.Context) ([]string, error) {
+					return []string{"enum-label"}, nil
+				},
 				upsertChromiumHistogramEnum: func(_ context.Context,
 					_ gcpspanner.ChromiumHistogramEnum) (*string, error) {
 					return valuePtr("enumID"), nil
@@ -195,48 +235,34 @@ func TestChromiumHistogramEnumConsumer_SaveHistogramEnums(t *testing.T) {
 	}
 }
 
-func TestEnumLabelToFeatureKey(t *testing.T) {
-	tests := []struct {
-		name  string
-		label string
-		want  string
-	}{
-		{
-			name:  "Simple lowercase",
-			label: "simple",
-			want:  "simple",
-		},
-		{
-			name:  "typical",
-			label: "TypicalCase",
-			want:  "typical-case",
-		},
-		{
-			name:  "With numbers in the middle",
-			label: "With123Numbers",
-			want:  "with-123-numbers",
-		},
-		{
-			name:  "Starting with number",
-			label: "123Abc",
-			want:  "123-abc",
-		},
-		{
-			name:  "Consecutive uppercase letters",
-			label: "ABCTest",
-			want:  "a-b-c-test",
-		},
-		{
-			name:  "Mixed case with numbers and consecutive uppercase",
-			label: "ABC123defGHI456Jkl",
-			want:  "a-b-c-123def-g-h-i-456-jkl",
-		},
+func TestCreateEnumToFeatureKeyMap(t *testing.T) {
+	featureKeys := []string{
+		"canvas-2d-color-management",
+		"http3",
+		"intersection-observer-v2",
+		"view-transitions",
+		// Special cases
+		"float16array",
+		"uint8array-base64-hex",
 	}
-	for _, tc := range tests {
-		t.Run(tc.name, func(t *testing.T) {
-			if got := enumLabelToFeatureKey(tc.label); got != tc.want {
-				t.Errorf("enumLabelToFeatureKey() = %v, want %v", got, tc.want)
-			}
-		})
+	// nolint: lll // WONTFIX: useful comment with SHA
+	want := map[string]string{
+		"Canvas2DColorManagement": "canvas-2d-color-management",
+		"Http3":                   "http3",
+		"IntersectionObserverV2":  "intersection-observer-v2",
+		"ViewTransitions":         "view-transitions",
+		/*
+			Special cases
+		*/
+		// https://source.chromium.org/chromium/chromium/src/+/main:third_party/blink/public/mojom/use_counter/metrics/webdx_feature.mojom;l=360;drc=822a70f9ac61a75babe9d24ddfc32ab475acc7e1
+		// https://github.com/web-platform-dx/web-features/blob/main/features/float16array.yml
+		"Float16Array": "float16array",
+		// https://source.chromium.org/chromium/chromium/src/+/main:third_party/blink/public/mojom/use_counter/metrics/webdx_feature.mojom;l=396;drc=822a70f9ac61a75babe9d24ddfc32ab475acc7e1
+		// https://github.com/web-platform-dx/web-features/blob/main/features/uint8array-base64-hex.yml
+		"Uint8ArrayBase64Hex": "uint8array-base64-hex",
+	}
+	got := createEnumToFeatureKeyMap(featureKeys)
+	if !reflect.DeepEqual(got, want) {
+		t.Errorf("createEnumToFeatureKeyMap()\ngot:  (%+v)\nwant: (%+v)\n", got, want)
 	}
 }

lib/gcpspanner/web_features.go

@@ -102,21 +102,33 @@ func (c *Client) GetIDFromFeatureKey(ctx context.Context, filter *FeatureIDFilte
 
 func (c *Client) fetchAllWebFeatureIDsWithTransaction(
 	ctx context.Context, txn *spanner.ReadOnlyTransaction) ([]string, error) {
-	var ids []string
-	iter := txn.Read(ctx, webFeaturesTable, spanner.AllKeys(), []string{"ID"})
+	return fetchColumnValuesWithTransaction[string](ctx, txn, webFeaturesTable, "ID")
+}
+
+func (c *Client) FetchAllFeatureKeys(ctx context.Context) ([]string, error) {
+	txn := c.ReadOnlyTransaction()
+	defer txn.Close()
+
+	return fetchColumnValuesWithTransaction[string](ctx, txn, webFeaturesTable, "FeatureKey")
+}
+
+func fetchColumnValuesWithTransaction[T any](
+	ctx context.Context, txn *spanner.ReadOnlyTransaction, table string, columnName string) ([]T, error) {
+	var values []T
+	iter := txn.Read(ctx, table, spanner.AllKeys(), []string{columnName})
 	defer iter.Stop()
 	err := iter.Do(func(row *spanner.Row) error {
-		var id string
-		if err := row.Column(0, &id); err != nil {
+		var value T
+		if err := row.Column(0, &value); err != nil {
 			return err
 		}
-		ids = append(ids, id)
+		values = append(values, value)
 
 		return nil
 	})
 	if err != nil {
 		return nil, err
 	}
 
-	return ids, nil
+	return values, nil
 }

lib/gcpspanner/web_features_test.go

@@ -125,4 +125,19 @@ func TestUpsertWebFeature(t *testing.T) {
 	if !slices.Equal[[]WebFeature](expectedPageAfterUpdate, features) {
 		t.Errorf("unequal features after update. expected %+v actual %+v", sampleFeatures, features)
 	}
+
+	expectedKeys := []string{
+		"feature1",
+		"feature2",
+		"feature3",
+		"feature4",
+	}
+	keys, err := spannerClient.FetchAllFeatureKeys(ctx)
+	if err != nil {
+		t.Errorf("unexpected error fetching all keys")
+	}
+	slices.Sort(keys)
+	if !slices.Equal(keys, expectedKeys) {
+		t.Errorf("unequal keys. expected %+v actual %+v", expectedKeys, keys)
+	}
 }

lib/go.mod

@@ -159,7 +159,7 @@ require (
 	golang.org/x/oauth2 v0.29.0
 	golang.org/x/sync v0.13.0 // indirect
 	golang.org/x/sys v0.32.0 // indirect
-	golang.org/x/text v0.24.0 // indirect
+	golang.org/x/text v0.24.0
 	golang.org/x/time v0.11.0 // indirect
 	google.golang.org/genproto v0.0.0-20250428153025-10db94c68c34 // indirect
 	google.golang.org/genproto/googleapis/api v0.0.0-20250428153025-10db94c68c34 // indirect