As a requirement you need to have allow_password_change field for any flow. There are 2 flows for reseting the password, one more web focused and other more mobile focused:
Main reset password flow (use auth headers)
This is the overall workflow for a User to reset their password:
user goes to a page on the front end site which contains a form with a single text field, they type their email address into this field and click a button to submit the form
that form submission sends a request to the API: POST /auth/password with some parameters: email (the email supplied in the field) & redirect_url (a page in the front end site that will contain a form with password and password_confirmation fields)
the API responds to this request by generating a reset_password_token and sending an email (the reset_password_instructions.html.erb file from devise) to the email address provided within the email parameter
we need to modify the reset_password_instructions.html.erb file to point to the API: GET /auth/password/edit
for example, if you have your API under the api/v1 namespaces: <%= link_to 'Change my password', edit_api_v1_user_password_url(reset_password_token: @token, config: message['client-config'].to_s, redirect_url: message['redirect-url'].to_s) %> (I came up with this link_to by referring to this line)
the user clicks the link in the email, which brings them to the 'Verify user by password reset token' endpoint (GET /password/edit)
this endpoint verifies the user and redirects them to the redirect_url (or the one you set in an initializer as default_password_reset_url) with the auth headers if they are who they claim to be (if their reset_password_token matches a User record)
this redirect_url is a page on the frontend which contains a password and password_confirmation field
the user submits the form on this frontend page, which sends a request to API: PUT /auth/password with the password and password_confirmation parameters. In addition headers need to be included from the url params (you get these from the url as query params). A side note, ensure that the header names follow the convention outlined in config/initializers/devise_token_auth.rb; at this time of writing it is: uid, client and access-token.
Ensure that the uid sent in the headers is not URL-escaped. e.g. it should be [email protected], not bob%40example.com
the API changes the user's password and responds back with a success message
the front end needs to manually redirect the user to its login page after receiving this success response
the user logs in
The next diagram shows how it works:
password reset flow
If you get in any trouble configuring or overriding the behavior, you can check the issue #604.
Mobile alternative flow (use reset_password_token)
This flow is enabled with require_client_password_reset_token (by default is false), it is also useful for webs. This flow was done because the main one doesn't support deep linking (if you want to reset the password in the mobile app). It works like the main one but instead of receiving and sending the auth headers, you need to send the reset_password_token, but just in case, we can explain it step by step:
1.
User fills out password reset request form (this POST /auth/password)
2.
User is sent an email
3.
User clicks confirmation link (this GET /auth/password/edit)
4.
Link leads to the client to the redirect_url (instead of the API) with a reset_password_token
5.
User submits password along with reset_password_token (this PUT /auth/password)