Fix 500 errors in the API when request context bears no project_id

This fixes 500 errors in the API that appeared when keystone authentication is
enabled, the request contexts bears no project_id, and the user doesn't have
admin rights.

This specific case did lead to badly built filters (with project_id being
None), which induced unexpected behaviour from the storage backend.

Change-Id: I62b416183f7841c4ca3f934022e90751a80b833f
Story: 2006948
Task: 37629

cloudkitty/api/v1/controllers/storage.py

@@ -62,6 +62,9 @@ class DataFramesController(rest.RestController):
         if pecan.request.context.is_admin:
             filters = {scope_key: tenant_id} if tenant_id else None
         else:
+            # Unscoped non-admin user
+            if project_id is None:
+                return {'dataframes': []}
             filters = {scope_key: project_id}
         try:
             resp = backend.retrieve(

cloudkitty/api/v2/dataframes/dataframes.py

@@ -84,6 +84,12 @@ class DataFrameList(base.BaseResource):
             metric_types = None
 
         if not flask.request.context.is_admin:
+            if flask.request.context.project_id is None:
+                # Unscoped non-admin user
+                return {
+                    'total': 0,
+                    'dataframes': []
+                }
             scope_key = CONF.collect.scope_key
             if filters:
                 filters[scope_key] = flask.request.context.project_id

cloudkitty/api/v2/summary/summary.py

@@ -45,6 +45,13 @@ class Summary(base.BaseResource):
         end = end or tzutils.get_next_month()
 
         if not flask.request.context.is_admin:
+            if flask.request.context.project_id is None:
+                # Unscoped non-admin user
+                return {
+                    'total': 0,
+                    'columns': [],
+                    'results': [],
+                }
             filters['project_id'] = flask.request.context.project_id
 
         metric_types = [filters.pop('type')] if 'type' in filters else None

cloudkitty/storage/v2/influx.py

@@ -161,6 +161,7 @@ class InfluxClient(object):
 
     @staticmethod
     def _get_filter(key, value):
+        format_string = ''
         if isinstance(value, six.string_types):
             format_string = """"{}"='{}'"""
         elif isinstance(value, (six.integer_types, float)):

releasenotes/notes/fix-project-id-none-d40df33fc7b7db23.yaml

@@ -0,0 +1,5 @@
+---
+fixes:
+  - |
+    The 500 errors happening on some API endpoints when keystone authentication
+    is enabled and the request context bears no ``project_id`` have been fixed.