Move APIRequest into its own file

1 files changed, 132 insertions, 0 deletions

diff --git a/nova/api/ec2/apirequest.py b/nova/api/ec2/apirequest.py
new file mode 100644
index 000000000..1fc84248b
--- /dev/null
+++ b/nova/api/ec2/apirequest.py
@@ -0,0 +1,132 @@
+# vim: tabstop=4 shiftwidth=4 softtabstop=4
+
+# Copyright 2010 United States Government as represented by the
+# Administrator of the National Aeronautics and Space Administration.
+# All Rights Reserved.
+#
+#    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.
+
+"""
+APIRequest class
+"""
+
+# TODO(termie): replace minidom with etree
+from xml.dom import minidom
+
+from twisted.internet import defer
+
+
+_c2u = re.compile('(((?<=[a-z])[A-Z])|([A-Z](?![A-Z]|$)))')
+
+
+def _camelcase_to_underscore(str):
+    return _c2u.sub(r'_\1', str).lower().strip('_')
+
+
+def _underscore_to_camelcase(str):
+    return ''.join([x[:1].upper() + x[1:] for x in str.split('_')])
+
+
+def _underscore_to_xmlcase(str):
+    res = _underscore_to_camelcase(str)
+    return res[:1].lower() + res[1:]
+
+
+class APIRequest(object):
+    def __init__(self, controller, action):
+        self.controller = controller
+        self.action = action
+
+    def send(self, context, **kwargs):
+
+        try:
+            method = getattr(self.controller,
+                             _camelcase_to_underscore(self.action))
+        except AttributeError:
+            _error = ('Unsupported API request: controller = %s,'
+                      'action = %s') % (self.controller, self.action)
+            _log.warning(_error)
+            # TODO: Raise custom exception, trap in apiserver,
+            #       and reraise as 400 error.
+            raise Exception(_error)
+
+        args = {}
+        for key, value in kwargs.items():
+            parts = key.split(".")
+            key = _camelcase_to_underscore(parts[0])
+            if len(parts) > 1:
+                d = args.get(key, {})
+                d[parts[1]] = value[0]
+                value = d
+            else:
+                value = value[0]
+            args[key] = value
+
+        for key in args.keys():
+            if isinstance(args[key], dict):
+                if args[key] != {} and args[key].keys()[0].isdigit():
+                    s = args[key].items()
+                    s.sort()
+                    args[key] = [v for k, v in s]
+
+        d = defer.maybeDeferred(method, context, **args)
+        d.addCallback(self._render_response, context.request_id)
+        return d
+
+    def _render_response(self, response_data, request_id):
+        xml = minidom.Document()
+
+        response_el = xml.createElement(self.action + 'Response')
+        response_el.setAttribute('xmlns',
+                                 'http://ec2.amazonaws.com/doc/2009-11-30/')
+        request_id_el = xml.createElement('requestId')
+        request_id_el.appendChild(xml.createTextNode(request_id))
+        response_el.appendChild(request_id_el)
+        if(response_data == True):
+            self._render_dict(xml, response_el, {'return': 'true'})
+        else:
+            self._render_dict(xml, response_el, response_data)
+
+        xml.appendChild(response_el)
+
+        response = xml.toxml()
+        xml.unlink()
+        _log.debug(response)
+        return response
+
+    def _render_dict(self, xml, el, data):
+        try:
+            for key in data.keys():
+                val = data[key]
+                el.appendChild(self._render_data(xml, key, val))
+        except:
+            _log.debug(data)
+            raise
+
+    def _render_data(self, xml, el_name, data):
+        el_name = _underscore_to_xmlcase(el_name)
+        data_el = xml.createElement(el_name)
+
+        if isinstance(data, list):
+            for item in data:
+                data_el.appendChild(self._render_data(xml, 'item', item))
+        elif isinstance(data, dict):
+            self._render_dict(xml, data_el, data)
+        elif hasattr(data, '__dict__'):
+            self._render_dict(xml, data_el, data.__dict__)
+        elif isinstance(data, bool):
+            data_el.appendChild(xml.createTextNode(str(data).lower()))
+        elif data != None:
+            data_el.appendChild(xml.createTextNode(str(data)))
+
+        return data_el