Introduce User.Created

For Network and Channel, the database only needed to define one Store
operation to create/update a record. However since User is missing an ID
we couldn't have a single StoreUser function like other types. We had
CreateUser and UpdatePassword. As new User fields get added (e.g. the
upcoming Admin flag) this isn't sustainable.

We could have CreateUser and UpdateUser, but this wouldn't be consistent
with other types. Instead, introduce User.Created which indicates
whether the record is already stored in the DB. This can be used in a
new StoreUser function to decide whether we need to UPDATE or INSERT
without relying on SQL constraints and INSERT OR UPDATE.

The ListUsers and GetUser functions set User.Created to true.

cmd/sojuctl/main.go

@@ -69,7 +69,7 @@ func main() {
 			Username: username,
 			Password: string(hashed),
 		}
-		if err := db.CreateUser(&user); err != nil {
+		if err := db.StoreUser(&user); err != nil {
 			log.Fatalf("failed to create user: %v", err)
 		}
 	case "change-password":
@@ -90,13 +90,13 @@ func main() {
 		}
 
 		user := soju.User{
+			Created:  true,
 			Username: username,
 			Password: string(hashed),
 		}
-		if err := db.UpdatePassword(&user); err != nil {
+		if err := db.StoreUser(&user); err != nil {
 			log.Fatalf("failed to update password: %v", err)
 		}
-
 	default:
 		flag.Usage()
 		if cmd != "help" {

db.go

@@ -10,6 +10,7 @@ import (
 )
 
 type User struct {
+	Created  bool
 	Username string
 	Password string // hashed
 }
@@ -199,6 +200,7 @@ func (db *DB) ListUsers() ([]User, error) {
 		if err := rows.Scan(&user.Username, &password); err != nil {
 			return nil, err
 		}
+		user.Created = true
 		user.Password = fromStringPtr(password)
 		users = append(users, user)
 	}
@@ -213,7 +215,7 @@ func (db *DB) GetUser(username string) (*User, error) {
 	db.lock.RLock()
 	defer db.lock.RUnlock()
 
-	user := &User{Username: username}
+	user := &User{Created: true, Username: username}
 
 	var password *string
 	row := db.db.QueryRow("SELECT password FROM User WHERE username = ?", username)
@@ -224,24 +226,24 @@ func (db *DB) GetUser(username string) (*User, error) {
 	return user, nil
 }
 
-func (db *DB) CreateUser(user *User) error {
+func (db *DB) StoreUser(user *User) error {
 	db.lock.Lock()
 	defer db.lock.Unlock()
 
 	password := toStringPtr(user.Password)
-	_, err := db.db.Exec("INSERT INTO User(username, password) VALUES (?, ?)", user.Username, password)
-	return err
-}
 
-func (db *DB) UpdatePassword(user *User) error {
-	db.lock.Lock()
-	defer db.lock.Unlock()
+	var err error
+	if user.Created {
+		_, err = db.db.Exec("UPDATE User SET password = ? WHERE username = ?",
+			password, user.Username)
+	} else {
+		_, err = db.db.Exec("INSERT INTO User(username, password) VALUES (?, ?)",
+			user.Username, password)
+		if err == nil {
+			user.Created = true
+		}
+	}
 
-	password := toStringPtr(user.Password)
-	_, err := db.db.Exec(`UPDATE User
-	SET password = ?
-	WHERE username = ?`,
-		password, user.Username)
 	return err
 }
 

user.go

@@ -547,5 +547,5 @@ func (u *user) deleteNetwork(id int64) error {
 
 func (u *user) updatePassword(hashed string) error {
 	u.User.Password = hashed
-	return u.srv.db.UpdatePassword(&u.User)
+	return u.srv.db.StoreUser(&u.User)
 }