postgres backup system

internal/manager/task/migrate.go

@@ -50,7 +50,7 @@ func (s *MigrateJob) Execute(ctx context.Context, progress *job.Progress) error
 	// always backup so that we can roll back to the previous version if
 	// migration fails
 	backupPath := s.BackupPath
-	if backupPath == "" {
+	if backupPath == "" || s.Database.DatabaseType() == sqlite.PostgresBackend {
 		backupPath = database.DatabaseBackupPath(s.Config.GetBackupDirectoryPath())
 	} else {
 		// check if backup path is a filename or path

pkg/sqlite/database.go

@@ -6,6 +6,7 @@ import (
 	"embed"
 	"errors"
 	"fmt"
+	"path/filepath"
 	"strconv"
 	"time"
 
@@ -358,6 +359,28 @@ func (db *Database) Version() uint {
 	return db.schemaVersion
 }
 
+func (db *Database) Reset() error {
+	if err := db.Remove(); err != nil {
+		return err
+	}
+
+	if err := db.Open(); err != nil {
+		return fmt.Errorf("[reset DB] unable to initialize: %w", err)
+	}
+
+	return nil
+}
+
+func (db *Database) AnonymousDatabasePath(backupDirectoryPath string) string {
+	fn := fmt.Sprintf("%s.anonymous.%d.%s", filepath.Base(db.DatabasePath()), db.schemaVersion, time.Now().Format("20060102_150405"))
+
+	if backupDirectoryPath != "" {
+		return filepath.Join(backupDirectoryPath, fn)
+	}
+
+	return fn
+}
+
 func (db *Database) Optimise(ctx context.Context) error {
 	logger.Info("Optimising database")
 

pkg/sqlite/database_postgres.go

@@ -2,12 +2,12 @@ package sqlite
 
 import (
 	"fmt"
+	"time"
 
 	"github.com/doug-martin/goqu/v9"
 	_ "github.com/doug-martin/goqu/v9/dialect/postgres"
 	_ "github.com/jackc/pgx/v5/stdlib"
 	"github.com/jmoiron/sqlx"
-	"github.com/stashapp/stash/pkg/logger"
 )
 
 type PostgresDB struct {
@@ -71,27 +71,51 @@ func (db *PostgresDB) open(disableForeignKeys bool, writable bool) (conn *sqlx.D
 	return conn, nil
 }
 
-func (db *PostgresDB) Remove() error {
-	logger.Warn("Postgres backend detected, ignoring Remove request")
-	return nil
+func (db *PostgresDB) Remove() (err error) {
+	_, err = db.writeDB.Exec(`
+DO $$ DECLARE
+    r RECORD;
+BEGIN
+    -- Disable triggers to avoid foreign key constraint violations
+    EXECUTE 'SET session_replication_role = replica';
+
+    -- Drop all tables
+    FOR r IN (SELECT tablename FROM pg_tables WHERE schemaname = 'public') LOOP
+        EXECUTE 'DROP TABLE IF EXISTS ' || quote_ident(r.tablename) || ' CASCADE';
+    END LOOP;
+
+    -- Re-enable triggers
+    EXECUTE 'SET session_replication_role = DEFAULT';
+END $$;
+`)
+
+	return err
 }
 
-func (db *PostgresDB) Reset() error {
-	logger.Warn("Postgres backend detected, ignoring Reset request")
-	return nil
+// getDBCloneCommand returns the command to clone a database from a backup file
+func getDBCloneCommand(backupPath string, dbname string) string {
+	return fmt.Sprintf(`
+SELECT pg_terminate_backend(pg_stat_activity.pid) FROM pg_stat_activity 
+WHERE pg_stat_activity.datname = '%[2]s' AND pid <> pg_backend_pid();
+CREATE DATABASE %[1]s WITH TEMPLATE %[2]s;
+`, backupPath, dbname)
 }
 
+// Backup creates a backup of the database at the given path.
 func (db *PostgresDB) Backup(backupPath string) (err error) {
-	logger.Warn("Postgres backend detected, ignoring Backup request")
-	return nil
+	_, err = db.writeDB.Exec(getDBCloneCommand(backupPath, "stash"))
+	return err
 }
 
-func (db *PostgresDB) RestoreFromBackup(backupPath string) error {
-	logger.Warn("Postgres backend detected, ignoring RestoreFromBackup request")
-	return nil
+// RestoreFromBackup restores the database from a backup file at the given path.
+func (db *PostgresDB) RestoreFromBackup(backupPath string) (err error) {
+	sqlcmd := "DROP DATABASE stash;\n" + getDBCloneCommand("stash", backupPath)
+
+	_, err = db.writeDB.Exec(sqlcmd)
+	return err
 }
 
+// DatabaseBackupPath returns the path to a database backup file for the given directory.
 func (db *PostgresDB) DatabaseBackupPath(backupDirectoryPath string) string {
-	logger.Warn("Postgres backend detected, ignoring DatabaseBackupPath request")
-	return ""
+	return fmt.Sprintf("stash_%d_%s", db.schemaVersion, time.Now().Format("20060102_150405"))
 }

pkg/sqlite/database_sqlite.go

@@ -103,18 +103,6 @@ func (db *SQLiteDB) Remove() error {
 	return nil
 }
 
-func (db *SQLiteDB) Reset() error {
-	if err := db.Remove(); err != nil {
-		return err
-	}
-
-	if err := db.Open(); err != nil {
-		return fmt.Errorf("[reset DB] unable to initialize: %w", err)
-	}
-
-	return nil
-}
-
 // Backup the database. If db is nil, then uses the existing database
 // connection.
 func (db *SQLiteDB) Backup(backupPath string) (err error) {
@@ -150,13 +138,3 @@ func (db *SQLiteDB) DatabaseBackupPath(backupDirectoryPath string) string {
 
 	return fn
 }
-
-func (db *SQLiteDB) AnonymousDatabasePath(backupDirectoryPath string) string {
-	fn := fmt.Sprintf("%s.anonymous.%d.%s", filepath.Base(db.DatabasePath()), db.schemaVersion, time.Now().Format("20060102_150405"))
-
-	if backupDirectoryPath != "" {
-		return filepath.Join(backupDirectoryPath, fn)
-	}
-
-	return fn
-}