From c8f85e40c49678e1c042e51bc7baf56bd74c06d7 Mon Sep 17 00:00:00 2001
From: Gonne <gonne@mathebau.de>
Date: Wed, 28 Sep 2022 12:00:45 +0200
Subject: [PATCH] Verbessere Fehlerbehandlung bei Tutoren und Sprechstunden

---
 repositories/request.go |  6 ++--
 repositories/tutor.go   | 71 ++++++++++++++++++++---------------------
 2 files changed, 38 insertions(+), 39 deletions(-)

diff --git a/repositories/request.go b/repositories/request.go
index e4ec7ed..762bd7d 100644
--- a/repositories/request.go
+++ b/repositories/request.go
@@ -37,7 +37,7 @@ func (r *RequestRepo) FindBySecret(secret string) (models.Request, error) {
 	var officeHourId int
 	err := row.Scan(&request.Id, &officeHourId, &request.Action, &request.Secret)
 	if err != nil {
-		return models.Request{}, err
+		return models.Request{}, fmt.Errorf("SQL-error scanning request row: %w", err)
 	}
 	request.OfficeHour, err = r.officeHourRepo.FindById(officeHourId)
 	return request, err
@@ -46,7 +46,7 @@ func (r *RequestRepo) FindBySecret(secret string) (models.Request, error) {
 func (r *RequestRepo) FindByOfficeHour(officeHour models.OfficeHour) ([]models.Request, error) {
 	rows, err := r.db.Query("SELECT * FROM request WHERE officeHour=?", officeHour.Id)
 	if err != nil {
-		return nil, err
+		return nil, fmt.Errorf("SQL-error selecting requests by office hour: %w", err)
 	}
 	defer rows.Close()
 
@@ -88,7 +88,7 @@ func (r *RequestRepo) Add(officeHour models.OfficeHour, action int) (int, error)
 	request := models.Request{Id: 0, OfficeHour: officeHour, Action: action, Secret: secret}
 	_, err = r.db.Exec("INSERT INTO `request` (officeHour, action, secret) VALUES (?,?,?)", officeHour.Id, action, secret)
 	if err != nil {
-		return 0, err
+		return 0, fmt.Errorf("SQL-error inserting new request: %w", err)
 	}
 	request, err = r.FindBySecret(secret)
 	if err != nil {
diff --git a/repositories/tutor.go b/repositories/tutor.go
index 3c84819..77fc32c 100644
--- a/repositories/tutor.go
+++ b/repositories/tutor.go
@@ -26,35 +26,15 @@ func (r *TutorRepo) FindByEmail(email string) ([]models.Tutor, error) {
 	}
 	defer rows.Close()
 
-	var tutors []models.Tutor
-	for rows.Next() {
-		var tutor models.Tutor
-		if err := rows.Scan(&tutor.Id, &tutor.Name, &tutor.Email); err != nil {
-			err = fmt.Errorf("Error scanning tutor row: %w", err)
-			log.Println(err.Error())
-			return tutors, err
-		}
-		tutors = append(tutors, tutor)
-	}
-	return tutors, nil
+	return r.getFromRows(rows)
 }
 
 func (r *TutorRepo) FindById(id int) (models.Tutor, error) {
-	row := r.db.QueryRow("SELECT * FROM tutor WHERE id=?", id)
-	var tutor models.Tutor
-	if err := row.Scan(&tutor.Id, &tutor.Name, &tutor.Email); err != nil {
-		return models.Tutor{}, err
-	}
-	return tutor, nil
+	return r.getFromRow(r.db.QueryRow("SELECT * FROM tutor WHERE id=?", id))
 }
 
 func (r *TutorRepo) FindByNameAndEmail(name string, email string) (models.Tutor, error) {
-	row := r.db.QueryRow("SELECT * FROM tutor WHERE email=? AND name=?", email, name)
-	var tutor models.Tutor
-	if err := row.Scan(&tutor.Id, &tutor.Name, &tutor.Email); err != nil {
-		return models.Tutor{}, err
-	}
-	return tutor, nil
+	return r.getFromRow(r.db.QueryRow("SELECT * FROM tutor WHERE email=? AND name=?", email, name))
 }
 
 func (r *TutorRepo) GetAll() ([]models.Tutor, error) {
@@ -64,6 +44,38 @@ func (r *TutorRepo) GetAll() ([]models.Tutor, error) {
 	}
 	defer rows.Close()
 
+	return r.getFromRows(rows)
+}
+func (r *TutorRepo) Add(tutor models.Tutor) (int, error) {
+	//Don't add identical tutors
+	existentTutor, err := r.FindByNameAndEmail(tutor.Name, tutor.Email)
+	if errors.Is(err, sql.ErrNoRows) {
+		sqlResult, err := r.db.Exec("INSERT INTO `tutor` (name, email) VALUES (?,?)", tutor.Name, tutor.Email)
+		if err != nil {
+			err = fmt.Errorf("SQL-error inserting new tutor: %w", err)
+			log.Println(err.Error())
+			return 0, err
+		}
+		id, lastInsertIdErr := sqlResult.LastInsertId()
+		if lastInsertIdErr != nil {
+			log.Printf("Error getting Id for new tutor: %s", lastInsertIdErr.Error())
+		}
+		return int(id), err
+	}
+	return existentTutor.Id, err
+}
+
+func (r *TutorRepo) getFromRow(row *sql.Row) (models.Tutor, error) {
+	var tutor models.Tutor
+	if err := row.Scan(&tutor.Id, &tutor.Name, &tutor.Email); err != nil {
+		err = fmt.Errorf("SQL-error scanning tutor row: %w", err)
+		log.Println(err.Error())
+		return models.Tutor{}, err
+	}
+	return tutor, nil
+}
+
+func (r *TutorRepo) getFromRows(rows *sql.Rows) ([]models.Tutor, error) {
 	var tutors []models.Tutor
 	for rows.Next() {
 		var tutor models.Tutor
@@ -76,16 +88,3 @@ func (r *TutorRepo) GetAll() ([]models.Tutor, error) {
 	}
 	return tutors, nil
 }
-func (r *TutorRepo) Add(tutor models.Tutor) (int, error) {
-	//Don't add identical tutors
-	existentTutor, err := r.FindByNameAndEmail(tutor.Name, tutor.Email)
-	if errors.Is(err, sql.ErrNoRows) {
-		sqlResult, err := r.db.Exec("INSERT INTO `tutor` (name, email) VALUES (?,?)", tutor.Name, tutor.Email)
-		id, lastInsertIdErr := sqlResult.LastInsertId()
-		if lastInsertIdErr != nil {
-			log.Printf("Error getting Id for new tutor: %s", lastInsertIdErr.Error())
-		}
-		return int(id), err
-	}
-	return existentTutor.Id, err
-}