feat: clanker fixxes + postgress

internal/db/import.go

@@ -0,0 +1,75 @@
+package db
+
+import (
+	"errors"
+	"fmt"
+	"io/fs"
+	"kooltap-updateserver/internal/models"
+	"log"
+	"os"
+
+	"github.com/glebarez/sqlite"
+	"gorm.io/gorm"
+	"gorm.io/gorm/logger"
+)
+
+// ImportSQLite copies releases from the old SQLite database at path into db,
+// once. It does nothing when the file does not exist. After a successful
+// import the file is renamed to path+".imported" so it is not imported again.
+func ImportSQLite(db *gorm.DB, path string) error {
+
+	if path == "" {
+		return nil
+	}
+	if _, err := os.Stat(path); errors.Is(err, fs.ErrNotExist) {
+		return nil
+	} else if err != nil {
+		return err
+	}
+
+	var existing int64
+	if err := db.Model(&models.Release{}).Count(&existing).Error; err != nil {
+		return err
+	}
+	if existing > 0 {
+		log.Printf("skipping SQLite import from %s: database already has %d releases", path, existing)
+		return nil
+	}
+
+	src, err := gorm.Open(sqlite.Open(path), &gorm.Config{Logger: logger.Discard})
+	if err != nil {
+		return fmt.Errorf("open sqlite %s: %w", path, err)
+	}
+	var releases []models.Release
+	err = src.Order("id").Find(&releases).Error
+	// Close before renaming the file below
+	if sqlDB, cerr := src.DB(); cerr == nil {
+		sqlDB.Close()
+	}
+	if err != nil {
+		return fmt.Errorf("read sqlite releases: %w", err)
+	}
+
+	err = db.Transaction(func(tx *gorm.DB) error {
+		if len(releases) > 0 {
+			if err := tx.Create(&releases).Error; err != nil {
+				return err
+			}
+		}
+		// Rows were inserted with their original IDs, so move the sequence past them
+		if tx.Dialector.Name() == "postgres" {
+			return tx.Exec(`SELECT setval(pg_get_serial_sequence('releases', 'id'), COALESCE((SELECT MAX(id) FROM releases), 0) + 1, false)`).Error
+		}
+		return nil
+	})
+	if err != nil {
+		return fmt.Errorf("import releases: %w", err)
+	}
+
+	if err := os.Rename(path, path+".imported"); err != nil {
+		log.Printf("imported SQLite database but could not rename it: %v", err)
+	}
+
+	log.Printf("imported %d releases from %s", len(releases), path)
+	return nil
+}