Update admin documentation for Prometheus collector

Added Prometheus collector-related configuration documentation
to administration documentation.

Depends-On: https://review.openstack.org/#/c/642989/
Change-Id: I8dc841dc7a0c20a5a5d486eb53be239ba082df48
Story: 2004974
Task: 29894

cloudkitty/collector/prometheus.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright 2018 Objectif Libre
 #
 #    Licensed under the Apache License, Version 2.0 (the "License"); you may
@@ -13,8 +12,6 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 #
-# @author: Martin CAMEY
-#
 from decimal import Decimal
 from decimal import localcontext
 from decimal import ROUND_HALF_UP
@@ -34,7 +31,7 @@ from cloudkitty import utils as ck_utils
 LOG = log.getLogger(__name__)
 
 PROMETHEUS_COLLECTOR_OPTS = 'collector_prometheus'
-pcollector_collector_opts = [
+collector_prometheus_opts = [
     cfg.StrOpt(
         'prometheus_url',
         default='',
@@ -59,7 +56,7 @@ pcollector_collector_opts = [
         help='Explicitly trust untrusted HTTPS responses',
     ),
 ]
-cfg.CONF.register_opts(pcollector_collector_opts, PROMETHEUS_COLLECTOR_OPTS)
+cfg.CONF.register_opts(collector_prometheus_opts, PROMETHEUS_COLLECTOR_OPTS)
 
 CONF = cfg.CONF
 

cloudkitty/common/config.py

@@ -19,6 +19,7 @@ import itertools
 import cloudkitty.api.app
 import cloudkitty.collector.gnocchi
 import cloudkitty.collector.monasca
+import cloudkitty.collector.prometheus
 import cloudkitty.config
 import cloudkitty.fetcher
 import cloudkitty.fetcher.gnocchi
@@ -43,6 +44,8 @@ _opts = [
         cloudkitty.collector.gnocchi.collector_gnocchi_opts))),
     ('collector_monasca', list(itertools.chain(
         cloudkitty.collector.monasca.collector_monasca_opts))),
+    ('collector_prometheus', list(itertools.chain(
+        cloudkitty.collector.prometheus.collector_prometheus_opts))),
     ('fetcher', list(itertools.chain(
         cloudkitty.fetcher.fetcher_opts))),
     ('fetcher_gnocchi', list(itertools.chain(

cloudkitty/tests/collectors/test_prometheus.py

@@ -184,6 +184,7 @@ class PrometheusCollectorTest(tests.TestCase):
 
 
 class PrometheusClientTest(tests.TestCase):
+
     class FakeResponse(object):
         """Mimics an HTTP ``requests`` response"""
 

doc/source/admin/configuration/collector.rst

@@ -64,6 +64,23 @@ Section: ``collector_monasca``.
 * ``monasca_service_name``: Defaults to ``monasca``. Name of the Monasca
   service in Keystone.
 
+
+Prometheus
+----------
+
+Section ``collector_prometheus``.
+
+* ``prometheus_url``: Prometheus HTTP API URL.
+
+* ``prometheus_user``: For HTTP basic authentication. The username.
+
+* ``prometheus_password``: For HTTP basic authentication. The password.
+
+* ``cafile``: Option to allow custom certificate authority file.
+
+* ``insecure``: Option to explicitly allow untrusted HTTPS connections.
+
+
 Metric collection
 =================
 
@@ -228,7 +245,7 @@ Gnocchi
   unless you know what you're doing.
 
 * ``aggregation_method``: Defaults to ``max``. The aggregation method to use
-  when retrieving measures in gnocchi. Must be one of ``min``, ``max``,
+  when retrieving measures from gnocchi. Must be one of ``min``, ``max``,
   ``mean``.
 
 Monasca
@@ -239,5 +256,12 @@ Monasca
   unless you know what you're doing.
 
 * ``aggregation_method``: Defaults to ``max``. The aggregation method to use
-  when retrieving measures in gnocchi. Must be one of ``min``, ``max``,
+  when retrieving measures from monasca. Must be one of ``min``, ``max``,
   ``mean``.
+
+Prometheus
+~~~~~~~~~~
+
+* ``aggregation_method``: Defaults to ``max``. The aggregation method to use
+  when retrieving measures from prometheus. Must be one of ``avg``, ``min``,
+  ``max``, ``sum``, ``count``, ``stddev``, ``stdvar``.

releasenotes/notes/rework-prometheus-collector-f9f34a3792888dad.yaml

@@ -2,5 +2,5 @@
 features:
   - |
     Prometheus collector now supports HTTPS with custom CA file,
-    an insecure option to allow untrusted certificate
+    an insecure option to allow an untrusted certificate
     and basic HTTP authentication.