Move timestamp registry to a sharable 'header' module

The timestamp registry is going to be used by other parsers
in the future. Thus it seems reasonable to move if from ipmi
to something sharable.

Conceptually, `timestamp_registry` operates on Oslo message
header - perhaps we can have a dedicated parser module for
such common things - 'header'.

Change-Id: I2ba2f0ae28f09dbccd818c82005d47c7a515dfd4

ironic_prometheus_exporter/messaging.py

@@ -14,6 +14,7 @@ import logging
 import os
 
 from ironic_prometheus_exporter.parsers import ipmi
+from ironic_prometheus_exporter.parsers import header
 from oslo_config import cfg
 from oslo_messaging.notify import notifier
 from prometheus_client import write_to_textfile, CollectorRegistry
@@ -45,7 +46,7 @@ class PrometheusFileDriver(notifier.Driver):
             if message['event_type'] == 'hardware.ipmi.metrics':
                 registry = CollectorRegistry()
                 node_message = message['payload']
-                ipmi.timestamp_registry(node_message, registry)
+                header.timestamp_registry(node_message, registry)
                 ipmi.category_registry(node_message, registry)
                 nodeFile = os.path.join(self.location,
                                         node_message['node_name'])

ironic_prometheus_exporter/parsers/header.py

@@ -0,0 +1,28 @@
+#    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.
+
+from datetime import datetime
+from prometheus_client import Gauge
+
+
+def timestamp_registry(node_information, ipmi_metric_registry):
+    metric = 'baremetal_last_payload_timestamp_seconds'
+    labels = {'node_name': node_information['node_name'],
+              'node_uuid': node_information['node_uuid'],
+              'instance_uuid': node_information['instance_uuid']}
+    dt_1970 = datetime(1970, 1, 1, 0, 0, 0)
+    dt_timestamp = datetime.strptime(node_information['timestamp'],
+                                     '%Y-%m-%dT%H:%M:%S.%f')
+    value = int((dt_timestamp - dt_1970).total_seconds())
+    g = Gauge(metric, 'Timestamp of the last received payload',
+              labelnames=labels.keys(), registry=ipmi_metric_registry)
+    g.labels(**labels).set(value)

ironic_prometheus_exporter/parsers/ipmi.py

@@ -15,7 +15,6 @@ import logging
 import pkg_resources
 import re
 
-from datetime import datetime
 from prometheus_client import Gauge
 
 # NOTE (iurygregory): most of the sensor readings come in the ipmi format
@@ -243,19 +242,5 @@ def category_registry(node_message, ipmi_metric_registry):
                               available_metrics)
 
 
-def timestamp_registry(node_information, ipmi_metric_registry):
-    metric = 'baremetal_last_payload_timestamp_seconds'
-    labels = {'node_name': node_information['node_name'],
-              'node_uuid': node_information['node_uuid'],
-              'instance_uuid': node_information['instance_uuid']}
-    dt_1970 = datetime(1970, 1, 1, 0, 0, 0)
-    dt_timestamp = datetime.strptime(node_information['timestamp'],
-                                     '%Y-%m-%dT%H:%M:%S.%f')
-    value = int((dt_timestamp - dt_1970).total_seconds())
-    g = Gauge(metric, get_metric_description(metric),
-              labelnames=list(labels), registry=ipmi_metric_registry)
-    g.labels(**labels).set(value)
-
-
 def get_metric_description(metric_name):
     return IPMI_METRICS_DESCRIPTION.get(metric_name, '')

ironic_prometheus_exporter/tests/json_samples/notification-header.json

@@ -0,0 +1,17 @@
+{
+    "priority": "INFO",
+    "event_type": "hardware.redfish.metrics",
+    "timestamp": "2019-03-29 20:12:26.885347",
+    "publisher_id": "None.localhost.localdomain",
+    "payload": {
+        "instance_uuid": "ac2aa2fd-6e1a-41c8-a114-2084c8705228",
+        "node_uuid": "ac2aa2fd-6e1a-41c8-a114-2084c8705228",
+        "event_type": "hardware.redfish.metrics.update",
+        "timestamp": "2019-03-29T20:12:22.989020",
+        "node_name": "knilab-master-u9",
+        "message_id": "85d6b2c8-fe57-432d-868a-330e0e28cf34",
+        "payload": {
+        }
+    },
+    "message_id": "2c0da1e8-1958-484f-9bdd-9117d717f7fa"
+}

ironic_prometheus_exporter/tests/test_header_parser.py

@@ -0,0 +1,48 @@
+#    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 json
+import os
+import unittest
+
+import ironic_prometheus_exporter
+from ironic_prometheus_exporter.parsers import header
+from prometheus_client import CollectorRegistry
+
+
+sample_file = os.path.join(
+    os.path.dirname(ironic_prometheus_exporter.__file__),
+    'tests', 'json_samples', 'notification-header.json')
+
+DATA = json.load(open(sample_file))
+
+
+class TestPayloadsParser(unittest.TestCase):
+
+    def setUp(self):
+        self.node_message = DATA['payload']
+        self.node_name = DATA['payload']['node_name']
+        self.node_uuid = DATA['payload']['node_uuid']
+        self.instance_uuid = DATA['payload']['instance_uuid']
+        self.timestamp = DATA['payload']['timestamp']
+        self.payload = DATA['payload']['payload']
+        self.metric_registry = CollectorRegistry()
+
+    def test_timestamp_metric(self):
+        header.timestamp_registry(self.node_message, self.metric_registry)
+
+        self.assertEqual(1553890342.0, self.metric_registry.get_sample_value(
+            'baremetal_last_payload_timestamp_seconds',
+            {'node_name': self.node_name,
+             'node_uuid': self.node_uuid,
+             'instance_uuid': self.instance_uuid}
+        ))

ironic_prometheus_exporter/tests/test_ipmi_parser.py

@@ -559,16 +559,6 @@ class TestPayloadsParser(unittest.TestCase):
              'entity_id': '7.1 (System Board)',
              'status': 'ok'}))
 
-    def test_timestamp_metric(self):
-        ipmi.timestamp_registry(self.node_message, self.metric_registry)
-
-        self.assertEqual(1553890342.0, self.metric_registry.get_sample_value(
-            'baremetal_last_payload_timestamp_seconds',
-            {'node_name': self.node_name,
-             'node_uuid': self.node_uuid,
-             'instance_uuid': self.instance_uuid}
-        ))
-
     def test_voltage_manager(self):
         voltage_category_info = ipmi.CATEGORY_PARAMS['voltage'].copy()
         voltage_category_info['data'] = \