Fixed import utils code

Added exception paththrough in case module cannot be loaded.

Change-Id: Ia429c25d550e11f95a6b7f62636e239eeb4022b8

rally/utils.py

@@ -68,9 +68,7 @@ def itersubclasses(cls, _seen=None):
 
 def try_append_module(name, modules):
     if name not in modules:
-        module = importutils.try_import(name)
-        if module is not None:
-            modules[name] = module
+        modules[name] = importutils.import_module(name)
 
 
 def import_modules_from_package(package):
@@ -81,9 +79,7 @@ def import_modules_from_package(package):
     path = [os.path.dirname(__file__), '..'] + package.split('.')
     path = os.path.join(*path)
     for filename in os.listdir(path):
-        module_name = '%s.%s' % (package, filename)
-        if filename.endswith('.py') and not filename.startswith('__'):
-            module_name = module_name[:-3]
-        elif os.path.isfile(os.path.join(path, filename)):
+        if filename.startswith('__') or not filename.endswith('.py'):
             continue
+        module_name = '%s.%s' % (package, filename[:-3])
         try_append_module(module_name, sys.modules)

tests/fixtures/import/broken.py

@@ -0,0 +1,5 @@
+'''This module is broken and cannot be imported.
+'''
+
+
+import missing.module.fromnowhere  # noqa

tests/fixtures/import/package/a.py

@@ -0,0 +1,6 @@
+'''Usual module.
+'''
+
+
+class Bazz:
+    pass

tests/fixtures/import/package/b.py

@@ -0,0 +1,7 @@
+'''Normal module that can be imported sucessfuly.
+'''
+
+
+class Bar:
+    def __init__(self, foo):
+        self._foo = foo

tests/test_utils.py

@@ -71,3 +71,15 @@ class ImportModulesTestCase(test.NoDBTestCase):
         modules = {}
         utils.try_append_module('rally.version', modules)
         self.assertTrue('rally.version' in modules)
+
+    def test_try_append_broken_module(self):
+        modules = {}
+        self.assertRaises(ImportError,
+                          utils.try_append_module,
+                          'tests.fixtures.import.broken',
+                          modules)
+
+    def test_import_modules_from_package(self):
+        utils.import_modules_from_package('tests.fixtures.import.package')
+        self.assertTrue('tests.fixtures.import.package.a' in sys.modules)
+        self.assertTrue('tests.fixtures.import.package.b' in sys.modules)