From 87afbfe6eb34e7a8c8372509c967e3c8f05b7788 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jo=C3=A3o=20Santos?= <joao.santos@zalando.de>
Date: Wed, 8 Jun 2016 15:11:06 +0200
Subject: [PATCH] #218 Raise import errors on endpoint handling

---
 connexion/utils.py  | 13 +++++++++++--
 tests/test_api.py   |  5 ++---
 tests/test_utils.py | 15 ++++++++++++++-
 3 files changed, 27 insertions(+), 6 deletions(-)

diff --git a/connexion/utils.py b/connexion/utils.py
index 86dc2848e..414bafc0d 100644
--- a/connexion/utils.py
+++ b/connexion/utils.py
@@ -99,14 +99,23 @@ def get_function_from_name(function_name):
     """
     module_name, attr_path = function_name.rsplit('.', 1)
     module = None
+    last_import_error = None
 
     while not module:
+
         try:
             module = importlib.import_module(module_name)
-        except ImportError:
+        except ImportError as import_error:
+            last_import_error = import_error
             module_name, attr_path1 = module_name.rsplit('.', 1)
             attr_path = '{0}.{1}'.format(attr_path1, attr_path)
-    function = deep_getattr(module, attr_path)
+    try:
+        function = deep_getattr(module, attr_path)
+    except AttributeError:
+        if last_import_error:
+            raise last_import_error
+        else:
+            raise
     return function
 
 
diff --git a/tests/test_api.py b/tests/test_api.py
index 483be5449..11cde4d6e 100644
--- a/tests/test_api.py
+++ b/tests/test_api.py
@@ -1,10 +1,9 @@
 import pathlib
 
+import pytest
 from connexion.api import Api
 from swagger_spec_validator.common import SwaggerValidationError
 
-import pytest
-
 TEST_FOLDER = pathlib.Path(__file__).parent
 
 
@@ -28,7 +27,7 @@ def test_template():
 
 
 def test_invalid_operation_does_stop_application_to_setup():
-    with pytest.raises(AttributeError):
+    with pytest.raises(ImportError):
         Api(TEST_FOLDER / "fakeapi/op_error_api.yaml", "/api/v1.0",
             {'title': 'OK'})
 
diff --git a/tests/test_utils.py b/tests/test_utils.py
index 4270248e7..b9416685f 100644
--- a/tests/test_utils.py
+++ b/tests/test_utils.py
@@ -2,8 +2,8 @@
 
 import connexion.app
 import connexion.utils as utils
-
 import pytest
+from mock import MagicMock
 
 
 def test_flaskify_path():
@@ -26,6 +26,19 @@ def test_get_function_from_name():
     assert function(2.7) == 3
 
 
+def test_get_function_from_name_attr_error(monkeypatch):
+    """
+    Test attribute error without import error on get_function_from_name.
+    Attribute errors due to import errors are tested on
+    test_api.test_invalid_operation_does_stop_application_to_setup
+    """
+    deep_attr_mock = MagicMock()
+    deep_attr_mock.side_effect = AttributeError
+    monkeypatch.setattr("connexion.utils.deep_getattr", deep_attr_mock)
+    with pytest.raises(AttributeError):
+        utils.get_function_from_name('math.ceil')
+
+
 def test_get_function_from_name_for_class_method():
     function = utils.get_function_from_name('connexion.app.App.common_error_handler')
     assert function == connexion.app.App.common_error_handler