Load options before importing packages

Importing modules from the package (rally plugin) can fail while trying
to access proper configuration options. To solve this issue, we need to
load options before loading modules itselves.

Change-Id: I387ed4f6af809e1306d30fb9903d65668eb14839

rally/common/plugin/discover.py

@@ -65,8 +65,8 @@ def import_modules_from_package(package):
                 sys.modules[module_name] = importlib.import_module(module_name)
 
 
-def import_modules_by_entry_point():
+def find_packages_by_entry_point():
-    """Import plugins by entry-point 'rally_plugins'."""
+    """Find all packages with rally_plugins entry-point"""
     loaded_packages = []
 
     for package in pkg_resources.working_set:
@@ -79,6 +79,30 @@ def import_modules_by_entry_point():
 
         if "path" in entry_map:
             ep = entry_map["path"]
+            package_info["plugins_path"] = ep.module_name
+        if "options" in entry_map:
+            ep = entry_map["options"]
+            package_info["options"] = "%s:%s" % (
+                ep.module_name,
+                ep.attrs[0] if ep.attrs else "list_opts",
+            )
+
+        if package_info:
+            package_info.update(
+                name=package.project_name,
+                version=package.version)
+            loaded_packages.append(package_info)
+    return loaded_packages
+
+
+def import_modules_by_entry_point(_packages=None):
+    """Import plugins by entry-point 'rally_plugins'."""
+    loaded_packages = _packages or find_packages_by_entry_point()
+
+    for package in loaded_packages:
+        if "plugins_path" in package:
+            em = pkg_resources.get_entry_map(package["name"])
+            ep = em["rally_plugins"]["path"]
             try:
                 m = ep.load()
                 if hasattr(m, "__path__"):
@@ -93,26 +117,12 @@ def import_modules_by_entry_point():
                 msg = ("\t Failed to load plugins from module '%(module)s' "
                        "(package: '%(package)s')" %
                        {"module": ep.module_name,
-                        "package": "%s %s" % (package.project_name,
+                        "package": "%s %s" % (package["name"],
-                                              package.version)})
+                                              package["version"])})
                 if logging.is_debug():
                     LOG.exception(msg)
                 else:
                     LOG.warning(msg + (": %s" % six.text_type(e)))
-            else:
-                package_info["plugins_path"] = ep.module_name
-        if "options" in entry_map:
-            ep = entry_map["options"]
-            package_info["options"] = "%s:%s" % (
-                ep.module_name,
-                ep.attrs[0] if ep.attrs else "list_opts",
-            )
-
-        if package_info:
-            package_info.update(
-                name=package.project_name,
-                version=package.version)
-            loaded_packages.append(package_info)
     return loaded_packages
 
 

rally/plugins/__init__.py

@@ -43,10 +43,11 @@ def load():
             discover.import_modules_from_package("rally.plugins.openstack")
             discover.import_modules_from_package("rally.plugins.workload")
 
-        packages = discover.import_modules_by_entry_point()
+        packages = discover.find_packages_by_entry_point()
         for package in packages:
             if "options" in package:
                 opts.register_options_from_path(package["options"])
+        discover.import_modules_by_entry_point(_packages=packages)
 
         discover.load_plugins("/opt/rally/plugins/")
         discover.load_plugins(os.path.expanduser("~/.rally/plugins/"))

tests/unit/common/plugin/test_discover.py

@@ -193,6 +193,14 @@ class LoadExtraModulesTestCase(test.TestCase):
                     }})
         ]
 
+        def mock_get_entry_map(name, group=None):
+            self.assertIsNone(group)
+            for p in mock_pkg_resources.working_set:
+                if p.project_name == name:
+                    return p.entry_map
+
+        mock_pkg_resources.get_entry_map.side_effect = mock_get_entry_map
+
         # use random uuid to not have conflicts in sys.modules
         packages = [[(mock.Mock(), str(uuid.uuid4()), None)] for i in range(3)]
         mock_walk_packages.side_effect = packages
@@ -205,9 +213,6 @@ class LoadExtraModulesTestCase(test.TestCase):
             for ep_name, ep in entry_map.items():
                 if ep_name == "path":
                     ep.load.assert_called_once_with()
-                    if package.project_name == "error":
-                        self.assertNotIn(package.project_name, data)
-                    else:
                     self.assertIn(package.project_name, data)
                     self.assertEqual(package.version,
                                      data[package.project_name]["version"])