[bugfix] Drop status indices AFTER updating visibility (#3795)

* [bugfix] Drop status indices AFTER updating visibility

* rename to status vis indices just to indicate they're only used in the statuses hook func

---------

Co-authored-by: kim <grufwub@gmail.com>

internal/db/bundb/migrations/20241121121623_enum_strings_to_ints.go

@@ -32,20 +32,8 @@ func init() {
 	up := func(ctx context.Context, db *bun.DB) error {
 		return db.RunInTx(ctx, nil, func(ctx context.Context, tx bun.Tx) error {
 
-			// Tables with visibility types.
+			// Status visibility type indices.
-			var visTables = []struct {
+			var statusVisIndices = []struct {
-				Table   string
-				Column  string
-				Default *new_gtsmodel.Visibility
-			}{
-				{Table: "statuses", Column: "visibility"},
-				{Table: "sin_bin_statuses", Column: "visibility"},
-				{Table: "account_settings", Column: "privacy", Default: util.Ptr(new_gtsmodel.VisibilityDefault)},
-				{Table: "account_settings", Column: "web_visibility", Default: util.Ptr(new_gtsmodel.VisibilityDefault)},
-			}
-
-			// Visibility type indices.
-			var visIndices = []struct {
 				name  string
 				cols  []string
 				order string
@@ -67,10 +55,20 @@ func init() {
 				},
 			}
 
-			// Before making changes to the visibility col
+			// Tables with visibility types.
-			// we must drop all indices that rely on it.
+			var visTables = []struct {
-			log.Info(ctx, "dropping old visibility indexes...")
+				Table                string
-			for _, index := range visIndices {
+				Column               string
+				Default              *new_gtsmodel.Visibility
+				IndexCleanupCallback func(ctx context.Context, tx bun.Tx) error
+			}{
+				{
+					Table:  "statuses",
+					Column: "visibility",
+					IndexCleanupCallback: func(ctx context.Context, tx bun.Tx) error {
+						// After new column has been created and
+						// populated, drop indices relying on old column.
+						for _, index := range statusVisIndices {
 							log.Infof(ctx, "dropping old index %s...", index.name)
 							if _, err := tx.NewDropIndex().
 								Index(index.name).
@@ -78,6 +76,22 @@ func init() {
 								return err
 							}
 						}
+						return nil
+					},
+				},
+				{
+					Table:  "sin_bin_statuses",
+					Column: "visibility",
+				},
+				{
+					Table:   "account_settings",
+					Column:  "privacy",
+					Default: util.Ptr(new_gtsmodel.VisibilityDefault)},
+				{
+					Table:   "account_settings",
+					Column:  "web_visibility",
+					Default: util.Ptr(new_gtsmodel.VisibilityDefault)},
+			}
 
 			// Get the mapping of old enum string values to new integer values.
 			visibilityMapping := visibilityEnumMapping[old_gtsmodel.Visibility]()
@@ -85,14 +99,14 @@ func init() {
 			// Convert all visibility tables.
 			for _, table := range visTables {
 				if err := convertEnums(ctx, tx, table.Table, table.Column,
-					visibilityMapping, table.Default); err != nil {
+					visibilityMapping, table.Default, table.IndexCleanupCallback); err != nil {
 					return err
 				}
 			}
 
 			// Recreate the visibility indices.
 			log.Info(ctx, "creating new visibility indexes...")
-			for _, index := range visIndices {
+			for _, index := range statusVisIndices {
 				log.Infof(ctx, "creating new index %s...", index.name)
 				q := tx.NewCreateIndex().
 					Table("statuses").
@@ -111,7 +125,7 @@ func init() {
 
 			// Migrate over old notifications table column over to new column type.
 			if err := convertEnums(ctx, tx, "notifications", "notification_type", //nolint:revive
-				notificationMapping, nil); err != nil {
+				notificationMapping, nil, nil); err != nil {
 				return err
 			}
 

internal/db/bundb/migrations/util.go

@@ -45,6 +45,7 @@ func convertEnums[OldType ~string, NewType ~int16](
 	column string,
 	mapping map[OldType]NewType,
 	defaultValue *NewType,
+	indexCleanupCallback func(context.Context, bun.Tx) error,
 ) error {
 	if len(mapping) == 0 {
 		return errors.New("empty mapping")
@@ -110,6 +111,13 @@ func convertEnums[OldType ~string, NewType ~int16](
 		log.Warnf(ctx, "total=%d does not match updated=%d", total, updated)
 	}
 
+	// Run index cleanup callback if set.
+	if indexCleanupCallback != nil {
+		if err := indexCleanupCallback(ctx, tx); err != nil {
+			return gtserror.Newf("error running index cleanup callback: %w", err)
+		}
+	}
+
 	// Drop the old column from table.
 	if _, err := tx.NewDropColumn().
 		Table(table).