Chapter 12 Password reset

Having completed account activation (and thereby verified the user’s email address) in Chapter 11, we’re now in a good position to implement password reset, and thereby handle the common case of users forgetting their passwords.¹ As we’ll see, many of the steps are similar to those for account activation, and we will have several opportunities to apply the lessons learned in Chapter 11. The beginning is different, though; unlike account activation, implementing password resets requires both a change to one of our views and two new forms (to handle email and new password submission).

Before writing any code, let’s mock up the expected sequence for resetting passwords. We’ll start by adding a “forgot password” link to the sample application’s login form (Figure 12.1). The “forgot password” link will go to a page with a form that takes in an email address and sends an email containing a password reset link (Figure 12.2). The reset link will go to a form for resetting the user’s password (with confirmation), as shown in Figure 12.3.

Figure 12.1: A mockup of a “forgot password” link.

Figure 12.2: A mockup of the “forgot password” form.

Figure 12.3: A mockup of the reset password form.

If you followed Chapter 11, you already have a mailer for password resets, which was generated in Section 11.2 (Listing 11.6). In this section, we’ll complete the necessary preliminaries by adding a resource and data model for password resets (Section 12.1) to go along with the mailer. We’ll implement the actual password reset in Section 12.3.

In analogy with account activations, our general plan is to make a Password Resets resource, with each password reset consisting of a reset token and corresponding reset digest. The primary sequence goes like this:

1. When a user requests a password reset, find the user by the submitted email address.
2. If the email address exists in the database, generate a reset token and corresponding reset digest.
3. Save the reset digest to the database, and then send an email to the user with a link containing the reset token and the user’s email address.
4. When the user clicks the link, find the user by email address, and then authenticate the token by comparing it to the reset digest.
5. If authenticated, present the user with the form for changing the password.