Move to a session based system for AuthTokens

models/session.go

@@ -0,0 +1,103 @@
+package models
+
+import (
+	"GoWeb/app"
+	"crypto/rand"
+	"encoding/hex"
+	"log"
+	"net/http"
+	"time"
+)
+
+type Session struct {
+	Id        int64
+	UserId    int64
+	AuthToken string
+	CreatedAt time.Time
+}
+
+// CreateSession creates a new session for a user
+func CreateSession(app *app.App, w http.ResponseWriter, userId int64) (Session, error) {
+	session := Session{}
+	session.UserId = userId
+	session.AuthToken = generateAuthToken(app)
+	session.CreatedAt = time.Now()
+
+	// If the AuthToken column for any user matches the token, set existingAuthToken to true
+	var existingAuthToken bool
+	err := app.Db.QueryRow("SELECT EXISTS(SELECT 1 FROM public.\"Session\" WHERE \"AuthToken\" = $1)", session.AuthToken).Scan(&existingAuthToken)
+	if err != nil {
+		log.Println("Error checking for existing auth token")
+		log.Println(err)
+		return Session{}, err
+	}
+
+	// If duplicate token found, recursively call function until unique token is generated
+	if existingAuthToken == true {
+		log.Println("Duplicate token found in sessions table, generating new token...")
+		return CreateSession(app, w, userId)
+	}
+
+	// Insert session into database
+	err = app.Db.QueryRow("INSERT INTO public.\"Session\" (\"UserId\", \"AuthToken\", \"CreatedAt\") VALUES ($1, $2, $3) RETURNING \"Id\"", session.UserId, session.AuthToken, session.CreatedAt).Scan(&session.Id)
+	if err != nil {
+		log.Println("Error inserting session into database")
+		return Session{}, err
+	}
+
+	createSessionCookie(app, w, session)
+	return session, nil
+}
+
+// Generates a random 64-byte string
+func generateAuthToken(app *app.App) string {
+	// Generate random bytes
+	b := make([]byte, 64)
+	_, err := rand.Read(b)
+	if err != nil {
+		log.Println("Error generating random bytes")
+	}
+
+	// Convert random bytes to hex string
+	return hex.EncodeToString(b)
+}
+
+// createSessionCookie creates a new session cookie
+func createSessionCookie(app *app.App, w http.ResponseWriter, session Session) {
+	cookie := &http.Cookie{
+		Name:     "session",
+		Value:    session.AuthToken,
+		Path:     "/",
+		MaxAge:   86400,
+		HttpOnly: true,
+		Secure:   true,
+	}
+
+	http.SetCookie(w, cookie)
+}
+
+// deleteSessionCookie deletes the session cookie
+func deleteSessionCookie(app *app.App, w http.ResponseWriter) {
+	cookie := &http.Cookie{
+		Name:   "session",
+		Value:  "",
+		Path:   "/",
+		MaxAge: -1,
+	}
+
+	http.SetCookie(w, cookie)
+}
+
+// DeleteSessionByAuthToken deletes a session from the database by AuthToken
+func DeleteSessionByAuthToken(app *app.App, w http.ResponseWriter, authToken string) error {
+	// Delete session from database
+	_, err := app.Db.Exec("DELETE FROM public.\"Session\" WHERE \"AuthToken\" = $1", authToken)
+	if err != nil {
+		log.Println("Error deleting session from database")
+		return err
+	}
+
+	deleteSessionCookie(app, w)
+
+	return nil
+}

models/user.go

@@ -2,11 +2,9 @@ package models
 
 import (
 	"GoWeb/app"
-	"crypto/rand"
 	"database/sql"
-	"encoding/hex"
+	"fmt"
 	"log"
-	"math"
 	"net/http"
 	"strconv"
 	"time"
@@ -18,7 +16,6 @@ type User struct {
 	Id        int64
 	Username  string
 	Password  string
-	AuthToken string
 	CreatedAt time.Time
 	UpdatedAt time.Time
 }
@@ -35,7 +32,7 @@ func GetCurrentUser(app *app.App, r *http.Request) (User, error) {
 	var userId int64
 
 	// Query row by session cookie
-	err = app.Db.QueryRow("SELECT \"Id\" FROM public.\"User\" WHERE \"AuthToken\" = $1", cookie.Value).Scan(&userId)
+	err = app.Db.QueryRow("SELECT \"Id\" FROM public.\"Session\" WHERE \"AuthToken\" = $1", cookie.Value).Scan(&userId)
 	if err != nil {
 		log.Println("Error querying session row with session: " + cookie.Value)
 		return User{}, err
@@ -49,7 +46,7 @@ func GetUserById(app *app.App, id int64) (User, error) {
 	user := User{}
 
 	// Query row by id
-	row, err := app.Db.Query("SELECT \"Id\", \"Username\", \"Password\", \"AuthToken\", \"CreatedAt\", \"UpdatedAt\" FROM public.\"User\" WHERE \"Id\" = $1", id)
+	row, err := app.Db.Query("SELECT \"Id\", \"Username\", \"Password\", \"CreatedAt\", \"UpdatedAt\" FROM public.\"User\" WHERE \"Id\" = $1", id)
 	if err != nil {
 		log.Println("Error querying user row with id: " + strconv.FormatInt(id, 10))
 		return User{}, err
@@ -63,22 +60,27 @@ func GetUserById(app *app.App, id int64) (User, error) {
 		}
 	}(row)
 
-	// Feed row data into user struct
+	return user, nil
-	row.Next()
+}
-	var authToken sql.NullString
+
-	err = row.Scan(&user.Id, &user.Username, &user.Password, &authToken, &user.CreatedAt, &user.UpdatedAt)
+// GetUserByUsername finds a users table row in the database by username and returns a struct representing this row
+func GetUserByUsername(app *app.App, username string) (User, error) {
+	user := User{}
+
+	// Query row by username
+	row, err := app.Db.Query("SELECT \"Id\", \"Username\", \"Password\", \"CreatedAt\", \"UpdatedAt\" FROM public.\"User\" WHERE \"Username\" = $1", username)
 	if err != nil {
-		log.Println("Error reading queried row from database")
+		log.Println("Error querying user row with username: " + username)
-		log.Println(err)
 		return User{}, err
 	}
 
-	// If the AuthToken column is null in the database it is handled here by setting user.authToken to an empty string
+	defer func(row *sql.Rows) {
-	if authToken.Valid {
+		err := row.Close()
-		user.AuthToken = authToken.String
+		if err != nil {
-	} else {
+			log.Println("Error closing database row")
-		user.AuthToken = ""
+			log.Println(err)
 		}
+	}(row)
 
 	return user, nil
 }
@@ -104,102 +106,30 @@ func CreateUser(app *app.App, username string, password string, createdAt time.T
 	return GetUserById(app, lastInsertId)
 }
 
-// AuthenticateUser validates the password for the specified user if it matches a session cookie is created and returned
+// AuthenticateUser validates the password for the specified user
-func AuthenticateUser(app *app.App, w http.ResponseWriter, username string, password string) (string, error) {
+func AuthenticateUser(app *app.App, w http.ResponseWriter, username string, password string) (Session, error) {
-	var hashedPassword []byte
+	var user User
 
-	// Query row by username, scan password column
+	// Query row by username
-	err := app.Db.QueryRow("SELECT \"Password\" FROM public.\"User\" WHERE \"Username\" = $1", username).Scan(&hashedPassword)
+	err := app.Db.QueryRow("SELECT \"Id\", \"Username\", \"Password\", \"CreatedAt\", \"UpdatedAt\" FROM public.\"User\" WHERE \"Username\" = $1", username).Scan(&user.Id, &user.Username, &user.Password, &user.CreatedAt, &user.UpdatedAt)
 	if err != nil {
-		log.Println("Unable to find row with username: " + username)
+		log.Println("Authentication error (user not found) for user:" + username)
 		log.Println(err)
-		return "", err
+		return Session{}, err
 	}
+	fmt.Println(user)
 
 	// Validate password
-	err = bcrypt.CompareHashAndPassword(hashedPassword, []byte(password))
+	err = bcrypt.CompareHashAndPassword([]byte(user.Password), []byte(password))
 	if err != nil { // Failed to validate password, doesn't match
 		log.Println("Authentication error (incorrect password) for user:" + username)
 		log.Println(err)
-		return "", err
+		return Session{}, err
 	} else {
-		return createSessionCookie(app, w, username)
+		return CreateSession(app, w, user.Id)
 	}
 }
 
-// createSessionCookie creates a new session token and cookie and returns the token value
-func createSessionCookie(app *app.App, w http.ResponseWriter, username string) (string, error) {
-	// Generate random 64 character string (alpha-numeric)
-	buff := make([]byte, int(math.Ceil(float64(64)/2)))
-	_, err := rand.Read(buff)
-	if err != nil {
-		log.Println("Error creating random buffer for session token value")
-		log.Println(err)
-		return "", err
-	}
-	str := hex.EncodeToString(buff)
-	token := str[:64]
-
-	// If the auth_token column for any user matches the token, set existingAuthToken to true
-	var existingAuthToken bool
-	err = app.Db.QueryRow("SELECT EXISTS(SELECT 1 FROM public.\"User\" WHERE \"AuthToken\" = $1)", token).Scan(&existingAuthToken)
-	if err != nil {
-		log.Println("Error checking for existing auth token")
-		log.Println(err)
-		return "", err
-	}
-
-	// If duplicate token found, recursively call function until unique token is generated
-	if existingAuthToken == true {
-		log.Println("Duplicate token found in sessions table")
-		return createSessionCookie(app, w, username)
-	}
-
-	// Store token in auth_token column of the users table
-	_, err = app.Db.Exec("UPDATE public.\"User\" SET \"AuthToken\" = $1 WHERE \"Username\" = $2", token, username)
-	if err != nil {
-		log.Println("Error setting auth_token column in users table")
-		log.Println(err)
-		return "", err
-	}
-
-	// Create session cookie, containing token
-	cookie := &http.Cookie{
-		Name:     "session",
-		Value:    token,
-		Path:     "/",
-		MaxAge:   86400,
-		HttpOnly: true,
-		Secure:   true,
-	}
-
-	http.SetCookie(w, cookie)
-
-	return token, nil
-}
-
-// ValidateSessionCookie validates the session cookie and returns the username of the user if valid
-func ValidateSessionCookie(app *app.App, r *http.Request) (string, error) {
-	// Get cookie from request
-	cookie, err := r.Cookie("session")
-	if err != nil {
-		log.Println("Error getting cookie from request")
-		log.Println(err)
-		return "", err
-	}
-
-	// Query row by token
-	var username string
-	err = app.Db.QueryRow("SELECT \"Username\" FROM public.\"User\" WHERE \"AuthToken\" = $1", cookie.Value).Scan(&username)
-	if err != nil {
-		log.Println("Error querying row by token")
-		log.Println(err)
-		return "", err
-	}
-
-	return username, nil
-}
-
 // LogoutUser deletes the session cookie and token from the database
 func LogoutUser(app *app.App, w http.ResponseWriter, r *http.Request) {
 	// Get cookie from request
@@ -211,10 +141,9 @@ func LogoutUser(app *app.App, w http.ResponseWriter, r *http.Request) {
 	}
 
 	// Set token to empty string
-	sqlStatement := "UPDATE public.\"User\" SET \"AuthToken\" = $1 WHERE \"AuthToken\" = $2"
+	err = DeleteSessionByAuthToken(app, w, cookie.Value)
-	_, err = app.Db.Exec(sqlStatement, "", cookie.Value)
 	if err != nil {
-		log.Println("Error setting auth_token column in users table")
+		log.Println("Error deleting session by auth token")
 		log.Println(err)
 		return
 	}