From e0675b50c0fa0cc737bfd814d45e495e3d7eaba6 Mon Sep 17 00:00:00 2001
From: Mazz Mosley <mazz@houseofmnowster.com>
Date: Mon, 10 Aug 2015 16:18:21 +0100
Subject: [PATCH] Retrieve sub property keys

The validation message was confusing by displaying only 1 level of
property of the service, even if the error was another level down.

Eg. if the 'files' property of 'extends' was the incorrect format,
it was displaying 'an invalid value for 'extends'', rather than
correctly retrieving 'files'.

Signed-off-by: Mazz Mosley <mazz@houseofmnowster.com>
---
 compose/config/validation.py | 14 ++++++++------
 tests/unit/config_test.py    | 21 ++++++++++++++++++++-
 2 files changed, 28 insertions(+), 7 deletions(-)

diff --git a/compose/config/validation.py b/compose/config/validation.py
index 7347c0128..aa2e0fcf4 100644
--- a/compose/config/validation.py
+++ b/compose/config/validation.py
@@ -99,12 +99,14 @@ def process_errors(errors):
                 if error.validator_value == "array":
                     msg = "an"
 
-                try:
-                    config_key = error.path[1]
-                    type_errors.append("Service '{}' has an invalid value for '{}', it should be {} {}".format(service_name, config_key, msg, error.validator_value))
-                except IndexError:
-                    config_key = error.path[0]
-                    root_msgs.append("Service '{}' doesn\'t have any configuration options. All top level keys in your docker-compose.yml must map to a dictionary of configuration options.'".format(config_key))
+                # pop the service name off our path
+                error.path.popleft()
+
+                if len(error.path) > 0:
+                    config_key = " ".join(["'%s'" % k for k in error.path])
+                    type_errors.append("Service '{}' configuration key {} contains an invalid type, it should be {} {}".format(service_name, config_key, msg, error.validator_value))
+                else:
+                    root_msgs.append("Service '{}' doesn\'t have any configuration options. All top level keys in your docker-compose.yml must map to a dictionary of configuration options.'".format(service_name))
             elif error.validator == 'required':
                 config_key = error.path[1]
                 required.append("Service '{}' option '{}' is invalid, {}".format(service_name, config_key, _clean_error_message(error.message)))
diff --git a/tests/unit/config_test.py b/tests/unit/config_test.py
index e023153a3..0ea375db4 100644
--- a/tests/unit/config_test.py
+++ b/tests/unit/config_test.py
@@ -124,7 +124,7 @@ class ConfigTest(unittest.TestCase):
             )
 
     def test_invalid_config_type_should_be_an_array(self):
-        expected_error_msg = "Service 'foo' has an invalid value for 'links', it should be an array"
+        expected_error_msg = "Service 'foo' configuration key 'links' contains an invalid type, it should be an array"
         with self.assertRaisesRegexp(ConfigurationError, expected_error_msg):
             config.load(
                 config.ConfigDetails(
@@ -690,6 +690,25 @@ class ExtendsTest(unittest.TestCase):
                 )
             )
 
+    def test_extends_validation_sub_property_key(self):
+        expected_error_msg = "Service 'web' configuration key 'extends' 'file' contains an invalid type"
+        with self.assertRaisesRegexp(ConfigurationError, expected_error_msg):
+            config.load(
+                config.ConfigDetails(
+                    {
+                        'web': {
+                            'image': 'busybox',
+                            'extends': {
+                                'file': 1,
+                                'service': 'web',
+                            }
+                        },
+                    },
+                    'tests/fixtures/extends',
+                    'filename.yml'
+                )
+            )
+
     def test_extends_validation_no_file_key_no_filename_set(self):
         dictionary = {'extends': {'service': 'web'}}