Try to make configs available for actors to import.

* Add comment explaining why configs is not present at the repository level.
* Modify sys.path to find the configs in actor_definition
* Fix actor config import of abc's for Python-2.7

leapp/actors/__init__.py

@@ -2,7 +2,13 @@
 import logging
 import os
 import sys
-from collections.abc import Sequence
+
+try:
+    # Python 3.3+
+    from collections.abc import Sequence
+except ImportError:
+    # Python 2.6 through 3.2
+    from collections import Sequence
 
 from leapp.actors.config import Config, retrieve_config
 from leapp.compat import string_types

leapp/configs/actor/__init__.py

@@ -0,0 +1,13 @@
+"""
+:py:mod:`leapp.configs.actor` represents the import location for private actor config schema that
+are placed in the actor's configs folder.
+
+
+Example:
+      If your actor has a configs folder with a schemas.py python module, import it
+      from the actor like this::
+
+      from leapp.libraries.actor import schemas
+
+This directory is intended for the definitions of actor configuration fields.
+"""

leapp/repository/__init__.py

@@ -144,8 +144,10 @@ def load(self, resolve=True, stage=None, skip_actors_discovery=False):
             self.log.debug("Extending LEAPP_COMMON_FILES for common file paths")
             self._extend_environ_paths('LEAPP_COMMON_FILES', self.files)
             self.log.debug("Installing repository provided common libraries loader hook")
+
             sys.meta_path.append(LeappLibrariesFinder(module_prefix='leapp.libraries.common', paths=self.libraries))
             sys.meta_path.append(LeappLibrariesFinder(module_prefix='leapp.workflows.api', paths=self.apis))
+            sys.meta_path.append(LeappLibrariesFinder(module_prefix='leapp.configs', paths=self.configs))
 
         if not skip_actors_discovery:
             if not stage or stage is _LoadStage.ACTORS:
@@ -189,6 +191,15 @@ def mapped_actor_data(data):
             })
             return data
 
+        # Note: `configs` are not present here because we are not yet making
+        # them globally accessible.  This is to force people to copy the config
+        # schema to their Actors instead of importing them from other Actors.
+        # That copy, in turn, is a good idea so the framework can return an
+        # error if two Actors share the same config but they have different
+        # schemafor it (for instance, if Actor Foo and Bar were sharing the
+        # same config entry but Actor Foo updated the entry in a later version.
+        # We need to error so Actor Bar can either be ported to the new
+        # definition or use a different config entry for it's needs.)
         return {
             'repo_dir': self._repo_dir,
             'actors': [mapped_actor_data(a.serialize()) for a in self.actors],
@@ -199,7 +210,8 @@ def mapped_actor_data(data):
             'workflows': filtered_serialization(get_workflows, self.workflows),
             'tools': [dict([('path', path)]) for path in self.relative_paths(self.tools)],
             'files': [dict([('path', path)]) for path in self.relative_paths(self.files)],
-            'libraries': [dict([('path', path)]) for path in self.relative_paths(self.libraries)]
+            'libraries': [dict([('path', path)]) for path in self.relative_paths(self.libraries)],
+            'configs': [dict([('path', path)]) for path in self.relative_paths(self.configs)],
         }
 
     def _extend_environ_paths(self, name, paths):
@@ -268,6 +280,13 @@ def libraries(self):
         """
         return tuple(self._definitions.get(DefinitionKind.LIBRARIES, ()))
 
+    @property
+    def configs(self):
+        """
+        :return: Tuple of configs in the repository
+        """
+        return tuple(self._definitions.get(DefinitionKind.CONFIGS, ()))
+
     @property
     def files(self):
         """

leapp/repository/actor_definition.py

@@ -314,6 +314,11 @@ def injected_context(self):
                 module_prefix='leapp.libraries.actor',
                 paths=[os.path.join(self._repo_dir, self.directory, x) for x in self.libraries]))
 
+        sys.meta_path.append(
+            LeappLibrariesFinder(
+                module_prefix='leapp.configs.actor',
+                paths=[os.path.join(self._repo_dir, self.directory, x) for x in self.configs]))
+
         previous_path = os.getcwd()
         os.chdir(os.path.join(self._repo_dir, self._directory))
         try:

leapp/repository/scan.py

@@ -89,6 +89,7 @@ def scan(repository, path):
         ('workflows', scan_workflows),
         ('files', scan_files),
         ('libraries', scan_libraries),
+        ('configs', scan_configs),
         ('tests', scan_tests),
         ('tools', scan_tools),
         ('apis', scan_apis))
@@ -224,6 +225,21 @@ def scan_libraries(repo, path, repo_path):
         repo.add(DefinitionKind.LIBRARIES, os.path.relpath(path, repo_path))
 
 
+def scan_configs(repo, path, repo_path):
+    """
+    Scans configs and adds them to the repository.
+
+    :param repo: Instance of the repository
+    :type repo: :py:class:`leapp.repository.Repository`
+    :param path: path to the configs
+    :type path: str
+    :param repo_path: path to the repository
+    :type repo_path: str
+    """
+    if os.listdir(path):
+        repo.add(DefinitionKind.CONFIGS, os.path.relpath(path, repo_path))
+
+
 def scan_tools(repo, path, repo_path):
     """
     Scans tools and adds them to the repository.