initial merge

Change-Id: Id7cef7826092e191654da872ee1e11c4c6f50ddf
Signed-off-by: Zhijiang Hu <hu.zhijiang@zte.com.cn>

code/horizon/horizon/loaders.py

@@ -0,0 +1,68 @@
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+"""
+Wrapper for loading templates from "templates" directories in panel modules.
+"""
+
+import os
+
+import django
+from django.conf import settings
+from django.template.base import TemplateDoesNotExist  # noqa
+
+if django.get_version() >= '1.8':
+    from django.template.engine import Engine
+    from django.template.loaders.base import Loader as tLoaderCls
+else:
+    from django.template.loader import BaseLoader as tLoaderCls  # noqa
+
+from django.utils._os import safe_join  # noqa
+
+# Set up a cache of the panel directories to search.
+panel_template_dirs = {}
+
+
+class TemplateLoader(tLoaderCls):
+    is_usable = True
+
+    def get_template_sources(self, template_name):
+        bits = template_name.split('/', 2)
+        if len(bits) == 3:
+            dash_name, panel_name, remainder = bits
+            key = os.path.join(dash_name, panel_name)
+            if key in panel_template_dirs:
+                template_dir = panel_template_dirs[key]
+                try:
+                    yield safe_join(template_dir, panel_name, remainder)
+                except UnicodeDecodeError:
+                    # The template dir name wasn't valid UTF-8.
+                    raise
+                except ValueError:
+                    # The joined path was located outside of template_dir.
+                    pass
+
+    def load_template_source(self, template_name, template_dirs=None):
+        for path in self.get_template_sources(template_name):
+            try:
+                with open(path) as file:
+                    return (file.read().decode(settings.FILE_CHARSET), path)
+            except IOError:
+                pass
+        raise TemplateDoesNotExist(template_name)
+
+
+if django.get_version() >= '1.8':
+    e = Engine()
+    _loader = TemplateLoader(e)
+else:
+    _loader = TemplateLoader()