Defaults and start of config

storage/storage.go

@@ -1,23 +1,26 @@
 package storage
 
 import (
+	"fmt"
+
 	"github.com/glebarez/sqlite"
 	"gorm.io/driver/postgres"
 	"gorm.io/gorm"
 )
 
+// Storage is responsible for all database, cache and media related actions
+// and serves as the lowest layer of the cake
 type Storage struct {
 	db *gorm.DB
 }
 
+// Build a new storage using sqlite as database backend
 func NewStorageSqlite(filePath string) (*Storage, error) {
 	db, err := gorm.Open(sqlite.Open(filePath))
 	if err != nil {
 		return nil, err
 	}
-	return &Storage{
-		db: db,
-	}, nil
+	return storageFromEmptyDb(db)
 }
 
 func NewStoragePostgres(dbUrl string) (*Storage, error) {
@@ -25,6 +28,35 @@ func NewStoragePostgres(dbUrl string) (*Storage, error) {
 	if err != nil {
 		return nil, err
 	}
+	return storageFromEmptyDb(db)
+}
+
+func storageFromEmptyDb(db *gorm.DB) (*Storage, error) {
+	// AutoMigrate ensures the db is in a state where all the structs given here
+	// have their own tables and relations setup. It also updates tables if necessary
+	db.AutoMigrate(
+		placeholderMediaFile,
+		placeholderUser(),
+		placeholderNote,
+		placeholderServer,
+	)
+	// Afterwards add the placeholder entries for each table.
+	// FirstOrCreate either creates a new entry or retrieves the first matching one
+	// We only care about the creation if there is none yet, so no need to carry the result over
+	if res := db.FirstOrCreate(placeholderMediaFile); res.Error != nil {
+		return nil, fmt.Errorf("failed to add placeholder media file: %w", res.Error)
+	}
+	if res := db.FirstOrCreate(placeholderUser()); res.Error != nil {
+		return nil, fmt.Errorf("failed to add placeholder media file: %w", res.Error)
+	}
+	if res := db.FirstOrCreate(placeholderNote); res.Error != nil {
+		return nil, fmt.Errorf("failed to add placeholder media file: %w", res.Error)
+	}
+	if res := db.FirstOrCreate(placeholderServer); res.Error != nil {
+		return nil, fmt.Errorf("failed to add placeholder media file: %w", res.Error)
+	}
+
+	// And finally, build the actual storage struct
 	return &Storage{
 		db: db,
 	}, nil