add context to keystonemiddleware

this pulls in context module from oslo as it's required for
notifications (which will be used in the audit middleware).

syncs context file to: Id66aba0c600896521a4a236e0a97859735419357

Implements: blueprint audit-middleware
Change-Id: Id983775129dcc795ab91d37d3ba7d90cc6f6a7a9

keystonemiddleware/openstack/common/context.py

@@ -0,0 +1,126 @@
+# Copyright 2011 OpenStack Foundation.
+# 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.
+
+"""
+Simple class that stores security context information in the web request.
+
+Projects should subclass this class if they wish to enhance the request
+context or provide additional information in their specific WSGI pipeline.
+"""
+
+import itertools
+import uuid
+
+
+def generate_request_id():
+    return b'req-' + str(uuid.uuid4()).encode('ascii')
+
+
+class RequestContext(object):
+
+    """Helper class to represent useful information about a request context.
+
+    Stores information about the security context under which the user
+    accesses the system, as well as additional request information.
+    """
+
+    user_idt_format = '{user} {tenant} {domain} {user_domain} {p_domain}'
+
+    def __init__(self, auth_token=None, user=None, tenant=None, domain=None,
+                 user_domain=None, project_domain=None, is_admin=False,
+                 read_only=False, show_deleted=False, request_id=None,
+                 instance_uuid=None):
+        self.auth_token = auth_token
+        self.user = user
+        self.tenant = tenant
+        self.domain = domain
+        self.user_domain = user_domain
+        self.project_domain = project_domain
+        self.is_admin = is_admin
+        self.read_only = read_only
+        self.show_deleted = show_deleted
+        self.instance_uuid = instance_uuid
+        if not request_id:
+            request_id = generate_request_id()
+        self.request_id = request_id
+
+    def to_dict(self):
+        user_idt = (
+            self.user_idt_format.format(user=self.user or '-',
+                                        tenant=self.tenant or '-',
+                                        domain=self.domain or '-',
+                                        user_domain=self.user_domain or '-',
+                                        p_domain=self.project_domain or '-'))
+
+        return {'user': self.user,
+                'tenant': self.tenant,
+                'domain': self.domain,
+                'user_domain': self.user_domain,
+                'project_domain': self.project_domain,
+                'is_admin': self.is_admin,
+                'read_only': self.read_only,
+                'show_deleted': self.show_deleted,
+                'auth_token': self.auth_token,
+                'request_id': self.request_id,
+                'instance_uuid': self.instance_uuid,
+                'user_identity': user_idt}
+
+    @classmethod
+    def from_dict(cls, ctx):
+        return cls(
+            auth_token=ctx.get("auth_token"),
+            user=ctx.get("user"),
+            tenant=ctx.get("tenant"),
+            domain=ctx.get("domain"),
+            user_domain=ctx.get("user_domain"),
+            project_domain=ctx.get("project_domain"),
+            is_admin=ctx.get("is_admin", False),
+            read_only=ctx.get("read_only", False),
+            show_deleted=ctx.get("show_deleted", False),
+            request_id=ctx.get("request_id"),
+            instance_uuid=ctx.get("instance_uuid"))
+
+
+def get_admin_context(show_deleted=False):
+    context = RequestContext(None,
+                             tenant=None,
+                             is_admin=True,
+                             show_deleted=show_deleted)
+    return context
+
+
+def get_context_from_function_and_args(function, args, kwargs):
+    """Find an arg of type RequestContext and return it.
+
+       This is useful in a couple of decorators where we don't
+       know much about the function we're wrapping.
+    """
+
+    for arg in itertools.chain(kwargs.values(), args):
+        if isinstance(arg, RequestContext):
+            return arg
+
+    return None
+
+
+def is_user_context(context):
+    """Indicates if the request context is a normal user."""
+    if not context:
+        return False
+    if context.is_admin:
+        return False
+    if not context.user_id or not context.project_id:
+        return False
+    return True

openstack-common.conf

@@ -1,6 +1,7 @@
 [DEFAULT]
 
 # The list of modules to copy from oslo-incubator
+module=context
 module=install_venv_common
 module=memorycache