= Documentation for Email Auth Feature

The email auth feature implements passwordless login using links sent via email.  It is
similar to the reset password feature, except you don't need to update
a password, or even have a password to login.  It depends on the login and
email_base features.

== Auth Value Methods

email_auth_additional_form_tags :: HTML fragment containing additional form tags to use on the email auth login form.
email_auth_deadline_column :: The column name in the +email_auth_table+ storing the deadline after which the token will be ignored.
email_auth_deadline_interval :: The amount of time for which to allow users to use email auth keys, 1 day by default. Only used if set_deadline_values? is true.
email_auth_email_last_sent_column :: The email auth last sent column in the +email_auth_table+, storing the last time the email was sent. Set to nil to always send an email when requested.
email_auth_email_recently_sent_error_flash :: The flash error to show if not sending an email auth email because another was sent recently.
email_auth_email_recently_sent_redirect :: Where to redirect after not sending an email auth email because another was sent recently.
email_auth_email_sent_notice_flash :: The flash notice to show after an email auth email has been sent.
email_auth_email_sent_redirect :: Where to redirect after sending an email auth email.
email_auth_email_subject :: The subject to use for email auth emails.
email_auth_error_flash :: The flash error to show if unable to login using email authentication.
email_auth_id_column :: The id column in the +email_auth_table+, should be a foreign key referencing the accounts table.
email_auth_key_column :: The email auth key/token column in the +email_auth_table+.
email_auth_key_param :: The parameter name to use for the email auth key.
email_auth_page_title :: The page title to use on the email auth form.
email_auth_request_additional_form_tags :: HTML fragment containing additional form tags to use on the email auth request form.
email_auth_request_button :: The text to use for the email auth request button.
email_auth_request_error_flash :: The flash error to show if not able to send an email auth email.
email_auth_request_route :: The route to the email auth request action.  Defaults to +email-auth-request+.
email_auth_route :: The route to the email auth action. Defaults to +email-auth+.
email_auth_session_key :: The key in the session to hold the email auth key temporarily.
email_auth_skip_resend_email_within :: The number of seconds required before sending another email auth email, 5 minutes by default.
email_auth_table :: The name of the table storing email auth keys.
force_email_auth? :: Whether email auth should be forced for the account.  False by default, which results in email auth only be used automatically if the account does not have a password.
no_matching_email_auth_key_error_flash :: The flash error message to show if attempting to access the email auth form with an invalid key.

== Auth Methods

account_from_email_auth_key(key) :: Retrieve the account using the given email auth key, or return nil if no account matches.
after_email_auth_request :: Run arbitrary code after sending the email auth email.
before_email_auth_request :: Run arbitrary code before sending the email auth email.
before_email_auth_request_route :: Run arbitrary code before handling an email auth request route.
before_email_auth_route :: Run arbitrary code before handling an email auth route.
create_email_auth_email :: A Mail::Message for the email auth email.
create_email_auth_key :: Add the email auth key data to the database.
email_auth_email_body :: The body to use for the email auth email.
email_auth_email_link :: The link to the email auth form in the email auth email.
email_auth_email_sent_response :: Return a response after successfully sending an email auth email. By default, redirects to +email_auth_email_sent_redirect+.
email_auth_key_insert_hash :: The hash to insert into the +email_auth_table+.
email_auth_key_value :: The email auth key for the current account.
email_auth_request_form :: The HTML to use for a form to request an email auth email, shown on the login page after the user submits their login, if +force_email_auth?+ is false and email authentication is not the only possible for of authentication for the user.
email_auth_view :: The HTML to use for the email auth form.
get_email_auth_email_last_sent :: Get the last time an email auth email is sent, or nil if there is no last sent time.
get_email_auth_key(id) :: Get the email auth key for the given account id from the database.
remove_email_auth_key :: Remove the email auth key for the current account, run after successful email auth.
send_email_auth_email :: Send the email auth email.
set_email_auth_email_last_sent :: Set the last time an email auth email is sent.  This is only called if there is a previous email auth token still active.
