Add module to work with OpenStackID service

With OpenStackID service (https://openstackid-resources.openstack.org)
Stackalytics can map email to user profile and retrieve affiliation
of the user. This patch is step one to move all user management
out of Stackalytics.

Change-Id: I43fc444f3ffb43191bfd4a672410dc1e2583426a

stackalytics/processor/openstackid_utils.py

@@ -0,0 +1,93 @@
+# 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.
+
+import collections
+import logging
+
+import requests
+
+from stackalytics.processor import utils
+
+
+LOG = logging.getLogger(__name__)
+
+OSID_URI = ('https://openstackid-resources.openstack.org/'
+            'api/public/v1/members?'
+            'filter=email==%s&relations=all_affiliations')
+INTERVAL_GAP_THRESHOLD = 60 * 60 * 24  # ignore gaps shorter than this
+
+_openstackid_session = requests.Session()
+
+
+def _openstack_profile_by_email(email):
+    LOG.debug('Lookup user email %s at OpenStackID', email)
+    uri = OSID_URI % email
+    data = utils.read_json_from_uri(uri, session=_openstackid_session)
+
+    if not data:
+        return None
+
+    if not data.get('data'):
+        return None  # not found
+
+    return data['data'][-1]  # return the last (most recent) record
+
+
+Interval = collections.namedtuple('Interval', ['start', 'end', 'value'])
+
+
+def _iterate_intervals(intervals, threshold=INTERVAL_GAP_THRESHOLD):
+    """Iterate intervals and fill gaps around of them
+
+    :param intervals: list of Interval objects
+    :param threshold: do not yield intervals shorted than threshold
+    """
+    if not intervals:
+        yield Interval(0, 0, None)
+    else:
+        intervals.sort(key=lambda x: x.start)
+
+        prev_start = 0
+
+        for interval in intervals:
+            if interval.start and interval.start - prev_start > threshold:
+                yield Interval(prev_start, interval.start, None)  # prior
+
+            yield interval
+
+            prev_start = interval.end
+
+        last_end = intervals[-1].end
+        if last_end:
+            yield Interval(last_end, 0, None)
+
+
+def user_profile_by_email(email):
+    data = _openstack_profile_by_email(email)
+
+    if not data:  # user is not found
+        return None
+
+    intervals = [Interval(a.get('start_date'), a.get('end_date') or 0,
+                          a.get('organization', {}).get('name'))
+                 for a in data.get('affiliations', [])]
+    companies = [dict(company_name=interval.value or '*independent',
+                      end_date=interval.end)
+                 for interval in _iterate_intervals(intervals)]
+    user = {
+        'openstack_id': data['id'],
+        'user_name': ' '.join([data.get('first_name'), data.get('last_name')]),
+        'emails': [email],
+        'companies': companies,
+    }
+    return user