added pickle and yaml cache plugins

added new base class for file based cache plugins as 99% of code was common
now also catches unexpected decoding exceptions
allows per module file modes and encoding
moved jsonfile code to base

lib/ansible/plugins/cache/yaml.py

@@ -0,0 +1,38 @@
+# (c) 2017, Brian Coca
+#
+# This file is part of Ansible
+#
+# Ansible is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# Ansible is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with Ansible.  If not, see <http://www.gnu.org/licenses/>.
+
+# Make coding more python3-ish
+from __future__ import (absolute_import, division, print_function)
+__metaclass__ = type
+
+import yaml
+
+from ansible.parsing.yaml.loader import AnsibleLoader
+from ansible.parsing.yaml.dumper import AnsibleDumper
+from ansible.plugins.cache.base import BaseFileCacheModule
+
+class CacheModule(BaseFileCacheModule):
+    """
+    A caching module backed by yaml files.
+    """
+    plugin_name = 'yaml'
+
+    def _load(self, f):
+        return AnsibleLoader(f).get_single_data()
+
+    def _dump(self, value, f):
+        yaml.dump(value, f, Dumper=AnsibleDumper, default_flow_style=False)