fix: technical debts left by the Sites, Authors and SEO slices, plus backend support for the new Sites and Authors pagination

internal/infrastructure/persistence/database/articleSlugBackfill.go

@@ -3,13 +3,15 @@ package database
 import (
 	"RenewCMS/internal/domain/article"
 	entity "RenewCMS/internal/infrastructure/persistence/models"
+	"slices"
 
 	"gorm.io/gorm"
 )
 
 const (
-	articleSlugIndexName      = "idx_articles_site_slug"
-	articleSlugIndexStatement = "CREATE UNIQUE INDEX " + articleSlugIndexName + " ON articles (site_id, slug)"
+	articleSlugIndexName         = "idx_articles_site_slug"
+	articleSlugBackfillBatchSize = 500
+	articleSlugIndexStatement    = "CREATE UNIQUE INDEX idx_articles_site_slug ON articles (site_id, slug)"
 )
 
 type slugOwner struct {
@@ -23,13 +25,22 @@ type slugAssignment struct {
 }
 
 func BackfillArticleSlugs(db *gorm.DB) error {
-	return db.Transaction(func(tx *gorm.DB) error {
-		var rows []entity.Article
-		if err := tx.Unscoped().Select("id", "site_id", "title", "slug", "deleted_at").Order("id ASC").Find(&rows).Error; err != nil {
+	var rows []entity.Article
+	if err := db.Unscoped().Select("id", "site_id", "title", "slug", "deleted_at").Order("id ASC").Find(&rows).Error; err != nil {
+		return err
+	}
+	assignments := planSlugAssignments(rows)
+	for batch := range slices.Chunk(assignments, articleSlugBackfillBatchSize) {
+		if err := writeSlugAssignments(db, batch); err != nil {
 			return err
 		}
-		assignments := planSlugAssignments(rows)
-		for _, assignment := range assignments {
+	}
+	return nil
+}
+
+func writeSlugAssignments(db *gorm.DB, batch []slugAssignment) error {
+	return db.Transaction(func(tx *gorm.DB) error {
+		for _, assignment := range batch {
 			if err := tx.Unscoped().Model(&entity.Article{}).Where("id = ?", assignment.id).UpdateColumn("slug", assignment.slug).Error; err != nil {
 				return err
 			}