Add ErrorObject to StripeError exceptions

stripe/api_resources/__init__.py

@@ -2,6 +2,7 @@
 
 # flake8: noqa
 
+from stripe.api_resources.error_object import ErrorObject, OAuthErrorObject
 from stripe.api_resources.list_object import ListObject
 
 from stripe.api_resources import checkout

stripe/api_resources/error_object.py

@@ -0,0 +1,69 @@
+from __future__ import absolute_import, division, print_function
+
+from stripe.util import merge_dicts
+from stripe.stripe_object import StripeObject
+
+
+class ErrorObject(StripeObject):
+    def refresh_from(
+        self,
+        values,
+        api_key=None,
+        partial=False,
+        stripe_version=None,
+        stripe_account=None,
+        last_response=None,
+    ):
+        # Unlike most other API resources, the API will omit attributes in
+        # error objects when they have a null value. We manually set default
+        # values here to facilitate generic error handling.
+        values = merge_dicts(
+            {
+                "charge": None,
+                "code": None,
+                "decline_code": None,
+                "doc_url": None,
+                "message": None,
+                "param": None,
+                "payment_intent": None,
+                "payment_method": None,
+                "setup_intent": None,
+                "source": None,
+                "type": None,
+            },
+            values,
+        )
+        return super(ErrorObject, self).refresh_from(
+            values,
+            api_key,
+            partial,
+            stripe_version,
+            stripe_account,
+            last_response,
+        )
+
+
+class OAuthErrorObject(StripeObject):
+    def refresh_from(
+        self,
+        values,
+        api_key=None,
+        partial=False,
+        stripe_version=None,
+        stripe_account=None,
+        last_response=None,
+    ):
+        # Unlike most other API resources, the API will omit attributes in
+        # error objects when they have a null value. We manually set default
+        # values here to facilitate generic error handling.
+        values = merge_dicts(
+            {"error": None, "error_description": None}, values
+        )
+        return super(OAuthErrorObject, self).refresh_from(
+            values,
+            api_key,
+            partial,
+            stripe_version,
+            stripe_account,
+            last_response,
+        )

stripe/error.py

@@ -1,5 +1,7 @@
 from __future__ import absolute_import, division, print_function
 
+import stripe
+from stripe.api_resources.error_object import ErrorObject
 from stripe.six import python_2_unicode_compatible
 
 
@@ -32,6 +34,7 @@ def __init__(
         self.headers = headers or {}
         self.code = code
         self.request_id = self.headers.get("request-id", None)
+        self.error = self.construct_error_object()
 
     def __str__(self):
         msg = self._message or "<empty message>"
@@ -56,6 +59,14 @@ def __repr__(self):
             self.request_id,
         )
 
+    def construct_error_object(self):
+        if self.json_body is None or "error" not in self.json_body:
+            return None
+
+        return ErrorObject.construct_from(
+            self.json_body["error"], stripe.api_key
+        )
+
 
 class APIError(StripeError):
     pass

stripe/oauth_error.py

@@ -1,5 +1,7 @@
 from __future__ import absolute_import, division, print_function
 
+import stripe
+from stripe.api_resources.error_object import OAuthErrorObject
 from stripe.error import StripeError
 
 
@@ -17,6 +19,12 @@ def __init__(
             description, http_body, http_status, json_body, headers, code
         )
 
+    def construct_error_object(self):
+        if self.json_body is None:
+            return None
+
+        return OAuthErrorObject.construct_from(self.json_body, stripe.api_key)
+
 
 class InvalidClientError(OAuthError):
     pass

stripe/util.py

@@ -205,6 +205,12 @@ def populate_headers(idempotency_key):
     return None
 
 
+def merge_dicts(x, y):
+    z = x.copy()
+    z.update(y)
+    return z
+
+
 class class_method_variant(object):
     def __init__(self, class_method_name):
         self.class_method_name = class_method_name

tests/test_error.py

@@ -52,6 +52,14 @@ def test_repr(self):
                 "request_id='123')"
             )
 
+    def test_error_object(self):
+        err = error.StripeError(
+            "message", json_body={"error": {"code": "some_error"}}
+        )
+        assert err.error is not None
+        assert err.error.code == "some_error"
+        assert err.error.charge is None
+
 
 class TestStripeErrorWithParamCode(object):
     def test_repr(self):

tests/test_oauth_error.py

@@ -0,0 +1,14 @@
+# -*- coding: utf-8 -*-
+
+from __future__ import absolute_import, division, print_function
+
+from stripe import oauth_error
+
+
+class TestOAuthError(object):
+    def test_error_object(self):
+        err = oauth_error.OAuthError(
+            "message", "description", json_body={"error": "some_oauth_error"}
+        )
+        assert err.error is not None
+        assert err.error.error == "some_oauth_error"