From 417b78cd738b93a610d4ef34b4067c383f3ecfd5 Mon Sep 17 00:00:00 2001
From: "Karl O. Pinc" <kop@karlpinc.com>
Date: Tue, 8 Dec 2020 17:26:29 -0600
Subject: [PATCH] Allow overriding of assets

---
 src/pgwui_common/assets.py     | 17 +++++++++++++---
 src/pgwui_common/exceptions.py | 14 +++++++++++++
 tests/test_assets.py           | 36 ++++++++++++++++++++++++++++++----
 tests/test_exceptions.py       | 12 ++++++++++++
 4 files changed, 72 insertions(+), 7 deletions(-)

diff --git a/src/pgwui_common/assets.py b/src/pgwui_common/assets.py
index 248d37f..39ab1b6 100644
--- a/src/pgwui_common/assets.py
+++ b/src/pgwui_common/assets.py
@@ -23,6 +23,9 @@
 '''
 
 import logging
+import pyramid.exceptions
+
+from . import exceptions as ex
 
 # Logging
 log = logging.getLogger(__name__)
@@ -31,8 +34,16 @@ log = logging.getLogger(__name__)
 def override_assets(config, settings):
     pgwui = settings['pgwui']
     if 'override_assets' not in pgwui:
-        return
+        return []
 
+    errors = []
     for asset, replacement in pgwui['override_assets'].items():
-        config.override_asset(asset, replacement)
-        log.debug(f'Overriding asset ({asset}) with ({replacement})')
+        try:
+            config.override_asset(asset, replacement)
+        except (pyramid.exceptions.ConfigurationError,
+                ModuleNotFoundError) as exp:
+            errors.append(ex.BadAssetOverrideError(asset, replacement, exp))
+        else:
+            log.debug(f'Overriding asset ({asset}) with ({replacement})')
+
+    return errors
diff --git a/src/pgwui_common/exceptions.py b/src/pgwui_common/exceptions.py
index cd69831..80152e7 100644
--- a/src/pgwui_common/exceptions.py
+++ b/src/pgwui_common/exceptions.py
@@ -125,6 +125,20 @@ class NotBooleanSettingError(Error):
             .format(key))
 
 
+class BadAssetOverrideError(Error):
+    def __init__(self, asset, new_asset, exp):
+        super().__init__(
+            f'The asset ({asset}) cannot be overridden with ({new_asset}):'
+            f' {exp}')
+
+
+class BadSettingError(Error):
+    def __init__(self, exp):
+        super().__init__(
+            f'Bad settings caused an error: {exp}'
+            '\nHint: Overriding non-existant assets can cause this problem')
+
+
 class BadPathError(Error):
     pass
 
diff --git a/tests/test_assets.py b/tests/test_assets.py
index 9650edf..9948319 100644
--- a/tests/test_assets.py
+++ b/tests/test_assets.py
@@ -22,7 +22,9 @@
 import pytest
 
 import logging
+import pyramid.exceptions
 import pgwui_common.assets as assets
+import pgwui_common.exceptions as common_ex
 
 from pgwui_testing import testing
 
@@ -35,7 +37,7 @@ pytestmark = pytest.mark.unittest
 mock_override_asset = testing.instance_method_mock_fixture('override_asset')
 
 
-# override_asset()
+# override_assets()
 
 @pytest.mark.parametrize(
     ('overrides', 'call_count'), [
@@ -43,9 +45,10 @@ mock_override_asset = testing.instance_method_mock_fixture('override_asset')
         ({'some_asset': 'new_asset'}, 1),
         ({'some_asset': 'new_asset',
           'other_asset': 'other new asset'}, 2)])
-def test_override_asset(
+def test_override_assets_success(
         caplog, pyramid_config, mock_override_asset, overrides, call_count):
-    '''override_asset() is called for each override
+    '''override_asset() is called and a debug message logged
+    for each good override
     '''
     caplog.set_level(logging.DEBUG)
     mocked_override_asset = mock_override_asset(pyramid_config)
@@ -54,7 +57,32 @@ def test_override_asset(
         settings = {'override_assets': overrides}
     else:
         settings = {}
-    assets.override_assets(pyramid_config, {'pgwui': settings})
+    result = assets.override_assets(pyramid_config, {'pgwui': settings})
 
+    assert result == []
     assert mocked_override_asset.call_count == call_count
     assert len(caplog.record_tuples) == call_count
+
+
+@pytest.mark.parametrize(
+    ('exception'), [
+        (pyramid.exceptions.ConfigurationError,),
+        (ModuleNotFoundError,)])
+def test_override_assets_failure(
+        caplog, pyramid_config, mock_override_asset, exception):
+    '''There is no logging when the override_asset call fails,
+    but an error is returned
+    '''
+    caplog.set_level(logging.DEBUG)
+    mocked_override_asset = mock_override_asset(pyramid_config)
+    mocked_override_asset.side_effect = exception
+
+    result = assets.override_assets(pyramid_config,
+                                    {'pgwui':
+                                     {'override_assets':
+                                      {'asset': 'new'}}})
+    assert len(result) == 1
+    assert isinstance(result[0], common_ex.BadAssetOverrideError)
+
+    logs = caplog.record_tuples
+    assert len(logs) == 0
diff --git a/tests/test_exceptions.py b/tests/test_exceptions.py
index 575412c..43ad7b8 100644
--- a/tests/test_exceptions.py
+++ b/tests/test_exceptions.py
@@ -24,6 +24,18 @@ import pytest
 import pgwui_common.exceptions as common_ex
 
 
+# Unit tests
+
+@pytest.mark.unittest
+def test_badsettingerror():
+    '''Takes an argument'''
+    # Thing is, this exception is only used by PGWUI_Server
+    # when exiting the configuration context raises a configuration
+    # execution error.
+    assert isinstance(common_ex.BadSettingError('foo'),
+                      common_ex.Error)
+
+
 # Functional tests
 
 @pytest.mark.integrationtest
-- 
2.34.1