Allowing Users to Log in and Log out

In this section, we'll add functionality that will allow registered users to log in and logged in users to log out of our application.

The code for this section will be organized as follows:

• models.user.go will be updated to check if the login credentials are valid,
• handlers.user.go will be updated with the new request handlers,
• routes.go will be updated with the new routes,
• templates/login.html will display the login form, and
• templates/menu.html will be updated with the Login and Logout menus.

Let's begin by creating a placeholder for the function to validate the login credentials, in models.user.go, as follows:

// models.user.go

func isUserValid(username, password string) bool {
    return false
}

We also need to update handlers.user.go with:

• A showLoginPage handler to show the login page,
• A performLogin handler to handle the login request, and
• A logout handler to handle the logout request.

For now, let's just add these handlers without any functionality so that we can write tests for them. Let's update the handlers.user.go file with the following code:

// handlers.user.go

func showLoginPage(c *gin.Context) {}

func performLogin(c *gin.Context) {}

func logout(c *gin.Context) {}