Clean up error handling

- use LocalizedErrorResponse to deduplicate error messages
- don't include email address in error message to reduce spoofing
  surface

gratipay/exceptions.py

@@ -4,7 +4,7 @@
 
 from __future__ import print_function, unicode_literals
 
-from aspen import Response
+from gratipay.utils.i18n import LocalizedErrorResponse
 
 
 class ProblemChangingUsername(Exception):
@@ -27,31 +27,37 @@ class UsernameAlreadyTaken(ProblemChangingUsername):
     msg = "The username '{}' is already taken."
 
 
-class ProblemChangingEmail(Response):
-    def __init__(self, *args):
-        Response.__init__(self, 400, self.msg.format(*args))
+class ProblemChangingEmail(LocalizedErrorResponse):
+    pass
 
 class EmailAlreadyVerified(ProblemChangingEmail):
-    msg = "{} is already verified for this Gratipay account."
+    def lazy_body(self, _):
+        return _("You have already added and verified that address.")
 
 class EmailTaken(ProblemChangingEmail):
-    msg = "{} is already connected to a different Gratipay account."
+    def lazy_body(self, _):
+        return _("That address is already linked to a different Gratipay account.")
 
 class CannotRemovePrimaryEmail(ProblemChangingEmail):
-    msg = "You cannot remove your primary email address."
+    def lazy_body(self, _):
+        return _("You cannot remove your primary email address.")
 
 class EmailNotOnFile(ProblemChangingEmail):
-    msg = "The email address '{}' is not on file for this package."
+    def lazy_body(self, _):
+         return _("That email address is not on file for this package.")
 
 class EmailNotVerified(ProblemChangingEmail):
-    msg = "The email address '{}' is not verified."
+    def lazy_body(self, _):
+         return _("That email address is not verified.")
 
 class TooManyEmailAddresses(ProblemChangingEmail):
-    msg = "You've reached the maximum number of email addresses we allow."
+    def lazy_body(self, _):
+         return _("You've reached the maximum number of email addresses we allow.")
 
 
-class Throttled(Exception):
-    msg = "You've initiated too many emails too quickly. Please try again in a minute or two."
+class Throttled(LocalizedErrorResponse):
+    def lazy_body(self, _):
+         return _("You've initiated too many emails too quickly. Please try again in a minute or two.")
 
 
 class ProblemChangingNumber(Exception):

gratipay/models/participant/email.py

@@ -87,7 +87,7 @@ def validate_email_verification_request(self, c, email, *packages):
         """Given a cursor, email, and packages, return ``None`` or raise.
         """
         if not all(email in p.emails for p in packages):
-            raise EmailNotOnFile(email)
+            raise EmailNotOnFile()
 
         owner_id = c.one("""
             SELECT participant_id
@@ -98,17 +98,17 @@ def validate_email_verification_request(self, c, email, *packages):
 
         if owner_id:
             if owner_id != self.id:
-                raise EmailTaken(email)
+                raise EmailTaken()
             elif packages:
                 pass  # allow reverify if claiming packages
             else:
-                raise EmailAlreadyVerified(email)
+                raise EmailAlreadyVerified()
 
         if len(self.get_emails()) > 9:
             if owner_id and owner_id == self.id and packages:
                 pass  # they're using an already-verified email to verify packages
             else:
-                raise TooManyEmailAddresses(email)
+                raise TooManyEmailAddresses()
 
 
     def get_email_verification_link(self, c, email, *packages):
@@ -197,7 +197,7 @@ def update_email(self, email):
         """Set the email address for the participant.
         """
         if not getattr(self.get_email(email), 'verified', False):
-            raise EmailNotVerified(email)
+            raise EmailNotVerified()
         username = self.username
         with self.db.get_cursor() as c:
             self.app.add_event( c

gratipay/utils/i18n.py

@@ -263,9 +263,13 @@ def set_locale():
 
 class LocalizedErrorResponse(Response):
 
-    def __init__(self, code, lazy_body, **kw):
+    def __repr__(self):
+        return "<{}: {}>".format(self.__class__.__name__, self)
+
+    def __init__(self, code=400, lazy_body=None, **kw):
         Response.__init__(self, code, '', **kw)
-        self.lazy_body = lazy_body
+        if lazy_body:
+            self.lazy_body = lazy_body
 
     def render_body(self, state):
         f = self.lazy_body

tests/py/test_email.py

@@ -7,7 +7,7 @@
 
 from gratipay.exceptions import CannotRemovePrimaryEmail, EmailTaken, EmailNotVerified
 from gratipay.exceptions import TooManyEmailAddresses, Throttled, EmailAlreadyVerified
-from gratipay.exceptions import EmailNotOnFile
+from gratipay.exceptions import EmailNotOnFile, ProblemChangingEmail
 from gratipay.testing import P, Harness
 from gratipay.testing.email import QueuedEmailHarness, SentEmailHarness
 from gratipay.models.participant import email as _email
@@ -36,7 +36,10 @@ def hit_email_spt(self, action, address, user='alice', should_fail=False):
         f = self.client.PxST if should_fail else self.client.POST
         data = {'action': action, 'address': address}
         headers = {b'HTTP_ACCEPT_LANGUAGE': b'en'}
-        return f('/~alice/emails/modify.json', data, auth_as=user, **headers)
+        response = f('/~alice/emails/modify.json', data, auth_as=user, **headers)
+        if issubclass(response.__class__, (Throttled, ProblemChangingEmail)):
+            response.render_body({'_': lambda a: a})
+        return response
 
     def verify_email(self, email, nonce, username='alice', should_fail=False):
         # Email address is encoded in url.

www/~/%username/emails/modify.json.spt

@@ -28,20 +28,8 @@ if not participant.email_lang:
 
 msg = None
 if action in ('add-email', 'resend'):
-    try:
-        participant.start_email_verification(address)
-    except EmailTaken:
-        raise Response(400, _( "{email_address} is already linked to a different Gratipay account."
-                             , email_address=address
-                              ))
-    except EmailAlreadyVerified:
-        raise Response(400, _( "You have already added and verified {email_address}."
-                             , email_address=address
-                              ))
-    except Throttled:
-        raise Response(400, _("You've initiated too many emails too quickly. Please try again in a minute or two."))
-    else:
-        msg = _("A verification email has been sent to {email_address}.", email_address=address)
+    participant.start_email_verification(address)
+    msg = _("Check your inbox for a verification email.")
 elif action == 'set-primary':
     participant.update_email(address)
 elif action == 'remove':