From f09e5c6f84d2e07d322a3004624fd270d9b37653 Mon Sep 17 00:00:00 2001
From: konrad <k@knt.li>
Date: Fri, 26 Jan 2018 16:00:18 +0100
Subject: [PATCH] Added check if the emailaddress is already used when creating
 a new user

---
 models/error.go                  | 16 ++++++++++++++++
 models/user_add_update.go        | 11 ++++++++++-
 models/user_test.go              |  8 +++++++-
 routes/api/v1/user_add_update.go |  5 +++++
 4 files changed, 38 insertions(+), 2 deletions(-)

diff --git a/models/error.go b/models/error.go
index 89653a2..4d75d13 100644
--- a/models/error.go
+++ b/models/error.go
@@ -22,6 +22,22 @@ func (err ErrUsernameExists) Error() string {
 	return fmt.Sprintf("a user with this username does already exist [user id: %d, username: %s]", err.UserID, err.Username)
 }
 
+// ErrUserEmailExists represents a "UserEmailExists" kind of error.
+type ErrUserEmailExists struct {
+	UserID   int64
+	Email string
+}
+
+// IsErrUserEmailExists checks if an error is a ErrUserEmailExists.
+func IsErrUserEmailExists(err error) bool {
+	_, ok := err.(ErrUserEmailExists)
+	return ok
+}
+
+func (err ErrUserEmailExists) Error() string {
+	return fmt.Sprintf("a user with this email does already exist [user id: %d, email: %s]", err.UserID, err.Email)
+}
+
 // ErrNoUsername represents a "UsernameAlreadyExists" kind of error.
 type ErrNoUsername struct {
 	UserID int64
diff --git a/models/user_add_update.go b/models/user_add_update.go
index 5cc0ee5..31afae5 100644
--- a/models/user_add_update.go
+++ b/models/user_add_update.go
@@ -14,7 +14,7 @@ func CreateUser(user User) (newUser User, err error) {
 		return User{}, ErrNoUsernamePassword{}
 	}
 
-	// Check if the user already existst
+	// Check if the user already existst with that username
 	existingUser, exists, err := GetUser(User{Username: newUser.Username})
 	if err != nil {
 		return User{}, err
@@ -23,6 +23,15 @@ func CreateUser(user User) (newUser User, err error) {
 		return User{}, ErrUsernameExists{existingUser.ID, existingUser.Username}
 	}
 
+	// Check if the user already existst with that username
+	existingUser, exists, err = GetUser(User{Email:newUser.Email})
+	if err != nil {
+		return User{}, err
+	}
+	if exists {
+		return User{}, ErrUserEmailExists{existingUser.ID, existingUser.Email}
+	}
+
 	// Hash the password
 	newUser.Password, err = hashPassword(user.Password)
 	if err != nil {
diff --git a/models/user_test.go b/models/user_test.go
index 826f876..53a1611 100644
--- a/models/user_test.go
+++ b/models/user_test.go
@@ -37,8 +37,14 @@ func TestCreateUser(t *testing.T) {
 	assert.Error(t, err)
 
 	// Check if it fails to create a user with just the same username
-	_, err = CreateUser(User{Username:dummyuser.Username})
+	_, err = CreateUser(User{Username:dummyuser.Username, Password: "1234"})
 	assert.Error(t, err)
+	assert.True(t, IsErrUsernameExists(err))
+
+	// Check if it fails to create one with the same email
+	_, err = CreateUser(User{Username: "noone", Password: "1234", Email:dummyuser.Email})
+	assert.Error(t, err)
+	assert.True(t, IsErrUserEmailExists(err))
 
 	// Check if it fails to create a user without password and username
 	_, err = CreateUser(User{})
diff --git a/routes/api/v1/user_add_update.go b/routes/api/v1/user_add_update.go
index 4992e4d..b24d4c6 100644
--- a/routes/api/v1/user_add_update.go
+++ b/routes/api/v1/user_add_update.go
@@ -68,6 +68,11 @@ func UserAddOrUpdate(c echo.Context) error {
 			return c.JSON(http.StatusBadRequest, models.Message{"A user with this username already exists."})
 		}
 
+		// Check for user with that email already exists
+		if models.IsErrUserEmailExists(err) {
+			return c.JSON(http.StatusBadRequest, models.Message{"A user with this email address already exists."})
+		}
+
 		// Check for no username provided
 		if models.IsErrNoUsername(err) {
 			return c.JSON(http.StatusBadRequest, models.Message{"Please specify a username."})