♻️ Transactionの処理を簡潔にする (#32)

server/repository/db/repository.go

@@ -8,43 +8,51 @@ import (
 	"github.com/traPtitech/piscon-portal-v2/server/repository"
 )
 
-type Repository struct {
-	db bob.DB
+type repoDB struct {
+	// prevent direct access to bob.DB by beginning with an underscore
+	_db bob.DB
 }
 
-func NewRepository(db *sql.DB) *Repository {
-	return &Repository{
-		db: bob.NewDB(db),
+type executorCtxKeyT struct{}
+
+var executorCtxKey = executorCtxKeyT{}
+
+func (db *repoDB) executor(ctx context.Context) bob.Executor {
+	if v := ctx.Value(executorCtxKey); v != nil {
+		exe, ok := v.(bob.Executor)
+		if ok {
+			return exe
+		}
 	}
+
+	return db._db
 }
 
-type txRepository struct {
-	tx bob.Tx
+type Repository struct {
+	*repoDB
 }
 
-func newTxRepository(tx bob.Tx) *txRepository {
-	return &txRepository{
-		tx: tx,
+func NewRepository(db *sql.DB) *Repository {
+	return &Repository{
+		repoDB: &repoDB{
+			_db: bob.NewDB(db),
+		},
 	}
 }
 
 func (r *Repository) Transaction(ctx context.Context, f func(ctx context.Context, r repository.Repository) error) error {
-	tx, err := r.db.BeginTx(ctx, nil)
+	tx, err := r._db.BeginTx(ctx, nil)
 	if err != nil {
 		return err
 	}
 	defer tx.Rollback() //nolint errcheck
 
-	txRepo := newTxRepository(tx)
+	ctx = context.WithValue(ctx, executorCtxKey, tx)
 
-	err = f(ctx, txRepo)
+	err = f(ctx, r)
 	if err != nil {
 		return err
 	}
 
 	return tx.Commit()
 }
-
-func (t *txRepository) Transaction(ctx context.Context, f func(ctx context.Context, r repository.Repository) error) error {
-	return f(ctx, t)
-}

server/repository/db/session.go

@@ -14,27 +14,15 @@ import (
 )
 
 func (r *Repository) FindSession(ctx context.Context, id string) (domain.Session, error) {
-	return findSession(ctx, r.db, id)
+	return findSession(ctx, r.executor(ctx), id)
 }
 
 func (r *Repository) CreateSession(ctx context.Context, session domain.Session) error {
-	return createSession(ctx, r.db, session)
+	return createSession(ctx, r.executor(ctx), session)
 }
 
 func (r *Repository) DeleteSession(ctx context.Context, id string) error {
-	return deleteSession(ctx, r.db, id)
-}
-
-func (t *txRepository) FindSession(ctx context.Context, id string) (domain.Session, error) {
-	return findSession(ctx, t.tx, id)
-}
-
-func (t *txRepository) CreateSession(ctx context.Context, session domain.Session) error {
-	return createSession(ctx, t.tx, session)
-}
-
-func (t *txRepository) DeleteSession(ctx context.Context, id string) error {
-	return deleteSession(ctx, t.tx, id)
+	return deleteSession(ctx, r.executor(ctx), id)
 }
 
 func findSession(ctx context.Context, executor bob.Executor, id string) (domain.Session, error) {

server/repository/db/user.go

@@ -14,19 +14,11 @@ import (
 )
 
 func (r *Repository) FindUser(ctx context.Context, id string) (domain.User, error) {
-	return findUser(ctx, r.db, id)
+	return findUser(ctx, r.executor(ctx), id)
 }
 
 func (r *Repository) CreateUser(ctx context.Context, user domain.User) error {
-	return createUser(ctx, r.db, user)
-}
-
-func (t *txRepository) FindUser(ctx context.Context, id string) (domain.User, error) {
-	return findUser(ctx, t.tx, id)
-}
-
-func (t *txRepository) CreateUser(ctx context.Context, user domain.User) error {
-	return createUser(ctx, t.tx, user)
+	return createUser(ctx, r.executor(ctx), user)
 }
 
 func findUser(ctx context.Context, executor bob.Executor, id string) (domain.User, error) {