feat: editor write path

internal/infrastructure/persistence/database/articleStoryBackfill.go

@@ -2,6 +2,7 @@ package database
 
 import (
 	entity "RenewCMS/internal/infrastructure/persistence/models"
+	"fmt"
 
 	"gorm.io/gorm"
 )
@@ -9,7 +10,9 @@ import (
 const (
 	articleStoriesMarker         = "article_stories"
 	articleStoryLanguageIndex    = "idx_articles_story_lang"
-	articleStoryLanguageIndexSQL = "CREATE UNIQUE INDEX idx_articles_story_lang ON articles (story_id, lang)"
+	articleStoryLanguageIndexSQL = "CREATE UNIQUE INDEX idx_articles_story_lang ON articles (story_id, lang, retired_id)"
+	articleStoryRetiredMarker    = "article_story_language_retired"
+	articleRetiredIDsMarker      = "article_retired_ids"
 )
 
 func BackfillArticleStories(db *gorm.DB) error {
@@ -35,9 +38,64 @@ func BackfillArticleStories(db *gorm.DB) error {
 	})
 }
 
+func BackfillRetiredArticles(db *gorm.DB) error {
+	return db.Transaction(func(tx *gorm.DB) error {
+		applied, err := markerApplied(tx, articleRetiredIDsMarker)
+		if err != nil || applied {
+			return err
+		}
+		if err := tx.Unscoped().Model(&entity.Article{}).Where("deleted_at IS NOT NULL AND retired_id = ?", 0).UpdateColumn("retired_id", gorm.Expr("id")).Error; err != nil {
+			return err
+		}
+		return applyMarker(tx, articleRetiredIDsMarker)
+	})
+}
+
+type duplicateStoryLanguage struct {
+	StoryID   uint32
+	Lang      string
+	RetiredID uint32
+	Versions  int
+}
+
+func checkStoryLanguagesUnique(db *gorm.DB) error {
+	var duplicates []duplicateStoryLanguage
+	err := db.Unscoped().Model(&entity.Article{}).
+		Select("story_id, lang, retired_id, COUNT(*) AS versions").
+		Group("story_id, lang, retired_id").
+		Having("COUNT(*) > 1").
+		Order("story_id ASC, lang ASC").
+		Limit(1).
+		Scan(&duplicates).Error
+	if err != nil || len(duplicates) == 0 {
+		return err
+	}
+	first := duplicates[0]
+	return fmt.Errorf("cannot create the unique index %s: story %d holds %d versions in language %q; merge or delete the extra versions, then start again", articleStoryLanguageIndex, first.StoryID, first.Versions, first.Lang)
+}
+
 func ensureArticleStoryLanguageIndex(db *gorm.DB) error {
-	if db.Migrator().HasIndex(&entity.Article{}, articleStoryLanguageIndex) {
+	replaced, err := markerApplied(db, articleStoryRetiredMarker)
+	if err != nil {
+		return err
+	}
+	indexed := db.Migrator().HasIndex(&entity.Article{}, articleStoryLanguageIndex)
+	if replaced && indexed {
 		return nil
 	}
-	return db.Exec(articleStoryLanguageIndexSQL).Error
+	if indexed {
+		if err := db.Migrator().DropIndex(&entity.Article{}, articleStoryLanguageIndex); err != nil {
+			return err
+		}
+	}
+	if err := checkStoryLanguagesUnique(db); err != nil {
+		return err
+	}
+	if err := db.Exec(articleStoryLanguageIndexSQL).Error; err != nil {
+		return err
+	}
+	if replaced {
+		return nil
+	}
+	return applyMarker(db, articleStoryRetiredMarker)
 }

internal/infrastructure/persistence/database/migrate.go

@@ -41,6 +41,9 @@ func Migrate(db *gorm.DB, publicURL string) error {
 	if err := SeedSiteLanguageSuggestions(db); err != nil {
 		return err
 	}
+	if err := BackfillRetiredArticles(db); err != nil {
+		return err
+	}
 	if err := ensureArticleStoryLanguageIndex(db); err != nil {
 		return err
 	}

internal/infrastructure/persistence/database/mysql.go

@@ -5,6 +5,7 @@ import (
 	"errors"
 	"fmt"
 	"net"
+	"slices"
 	"strings"
 	"time"
 
@@ -25,6 +26,8 @@ const (
 	redactedPassword     = "***"
 	mysqlLockNowait      = 3572
 	mysqlLockWaitTimeout = 1205
+	mysqlDeadlock        = 1213
+	mysqlSnapshotChanged = 1020
 )
 
 type mysqlDriver struct{}
@@ -88,7 +91,9 @@ func tableOptionsFor(db *gorm.DB) *gorm.DB {
 	return db
 }
 
+var mysqlContentionCodes = []uint16{mysqlLockNowait, mysqlLockWaitTimeout, mysqlDeadlock, mysqlSnapshotChanged}
+
 func (mysqlDriver) IsLockContention(err error) bool {
 	var failure *mysqldriver.MySQLError
-	return errors.As(err, &failure) && (failure.Number == mysqlLockNowait || failure.Number == mysqlLockWaitTimeout)
+	return errors.As(err, &failure) && slices.Contains(mysqlContentionCodes, failure.Number)
 }

internal/infrastructure/persistence/database/postgres.go

@@ -7,6 +7,7 @@ import (
 	"net"
 	"net/url"
 	"reflect"
+	"slices"
 	"time"
 
 	"github.com/jackc/pgx/v5/pgconn"
@@ -23,6 +24,8 @@ const (
 	postgresUTCCallback           = "renewcms:postgres_utc"
 	gormQueryCallback             = "gorm:query"
 	postgresLockNotAvailable      = "55P03"
+	postgresDeadlockDetected      = "40P01"
+	postgresSerializationFailure  = "40001"
 )
 
 var timeType = reflect.TypeOf(time.Time{})
@@ -109,7 +112,9 @@ func (postgresDriver) NewBackup(db *gorm.DB, directory string, now func() time.T
 	return NewPostgresBackup(db, directory, now)
 }
 
+var postgresContentionCodes = []string{postgresLockNotAvailable, postgresDeadlockDetected, postgresSerializationFailure}
+
 func (postgresDriver) IsLockContention(err error) bool {
 	var failure *pgconn.PgError
-	return errors.As(err, &failure) && failure.Code == postgresLockNotAvailable
+	return errors.As(err, &failure) && slices.Contains(postgresContentionCodes, failure.Code)
 }