billing: Update stripe error handling code.

stubs/stripe/error/__init__.pyi

@@ -1,8 +1,22 @@
+from typing import Any, Dict
+
+# List of StripeError's from https://stripe.com/docs/api/python#error_handling
+
 class StripeError(Exception):
     http_status: str
+    json_body: Dict[str, Any]
 
-class CardError(Exception):
-    http_status: str
-
-class InvalidRequestError(Exception):
+class CardError(StripeError):
+    ...
+
+class RateLimitError(StripeError):
+    ...
+
+class InvalidRequestError(StripeError):
+    ...
+
+class AuthenticationError(StripeError):
+    ...
+
+class APIConnectionError(StripeError):
     ...

zilencer/lib/stripe.py

@@ -73,6 +73,12 @@ class BillingError(Exception):
         self.description = description
         self.message = message
 
+class StripeCardError(BillingError):
+    pass
+
+class StripeConnectionError(BillingError):
+    pass
+
 def catch_stripe_errors(func: CallableT) -> CallableT:
     @wraps(func)
     def wrapped(*args: Any, **kwargs: Any) -> Any:
@@ -85,12 +91,22 @@ def catch_stripe_errors(func: CallableT) -> CallableT:
                                    "Plan objects not created. Please run ./manage.py setup_stripe")
         try:
             return func(*args, **kwargs)
+        # See https://stripe.com/docs/api/python#error_handling, though
+        # https://stripe.com/docs/api/ruby#error_handling suggests there are additional fields, and
+        # https://stripe.com/docs/error-codes gives a more detailed set of error codes
         except stripe.error.StripeError as e:
-            billing_logger.error("Stripe error: %d %s", e.http_status, e.__class__.__name__)
+            err = e.json_body.get('error', {})
+            billing_logger.error("Stripe error: %s %s %s %s" % (
+                e.http_status, err.get('type'), err.get('code'), err.get('param')))
             if isinstance(e, stripe.error.CardError):
-                raise BillingError('card error', e.json_body.get('error', {}).get('message'))
-            else:
-                raise BillingError('other stripe error', BillingError.CONTACT_SUPPORT)
+                # TODO: Look into i18n for this
+                raise StripeCardError('card error', err.get('message'))
+            if isinstance(e, stripe.error.RateLimitError) or \
+               isinstance(e, stripe.error.APIConnectionError):  # nocoverage TODO
+                raise StripeConnectionError(
+                    'stripe connection error',
+                    _("Something went wrong. Please wait a few seconds and try again."))
+            raise BillingError('other stripe error', BillingError.CONTACT_SUPPORT)
     return wrapped  # type: ignore # https://github.com/python/mypy/issues/1927
 
 @catch_stripe_errors

zilencer/tests/test_stripe.py

@@ -69,10 +69,11 @@ class StripeTest(ZulipTestCase):
         return match.group(1) if match else None
 
     @mock.patch("zilencer.lib.stripe.billing_logger.error")
-    def test_errors(self, mock_billing_logger_error: mock.Mock) -> None:
+    def test_catch_stripe_errors(self, mock_billing_logger_error: mock.Mock) -> None:
         @catch_stripe_errors
         def raise_invalid_request_error() -> None:
-            raise stripe.error.InvalidRequestError("Request req_oJU621i6H6X4Ez: No such token: x", None)
+            raise stripe.error.InvalidRequestError(
+                "Request req_oJU621i6H6X4Ez: No such token: x", None, json_body={})
         with self.assertRaises(BillingError) as context:
             raise_invalid_request_error()
         self.assertEqual('other stripe error', context.exception.description)
@@ -84,7 +85,7 @@ class StripeTest(ZulipTestCase):
             json_body = {"error": {"message": error_message}}
             raise stripe.error.CardError(error_message, "number", "invalid_number",
                                          json_body=json_body)
-        with self.assertRaises(BillingError) as context:
+        with self.assertRaises(StripeCardError) as context:
             raise_card_error()
         self.assertIn('not a valid credit card', context.exception.message)
         self.assertEqual('card error', context.exception.description)