Implement attach rate statsbeat metrics (#1053)

Author: lzchen

contrib/opencensus-ext-azure/CHANGELOG.md

@@ -4,6 +4,8 @@
 
 - Enable AAD authorization via TokenCredential
 ([#1021](https://github.com/census-instrumentation/opencensus-python/pull/1021))
+- Implement attach rate metrics via Statbeat
+([#1053](https://github.com/census-instrumentation/opencensus-python/pull/1053))
 
 ## 1.0.8
 Released 2021-05-13

contrib/opencensus-ext-azure/opencensus/ext/azure/common/__init__.py

@@ -108,14 +108,14 @@ def __init__(self, *args, **kwargs):
 
     _default = BaseObject(
         connection_string=None,
-        credential=None,
+        credential=None,  # Credential class used by AAD auth
         enable_local_storage=True,
-        enable_standard_metrics=True,
+        enable_standard_metrics=True,  # Used by metrics exporter, True to send standard metrics  # noqa: E501
         endpoint='https://dc.services.visualstudio.com/v2/track',
         export_interval=15.0,
         grace_period=5.0,
         instrumentation_key=None,
-        logging_sampling_rate=1.0,
+        logging_sampling_rate=1.0,  # Used by log exporter, controls sampling
         max_batch_size=100,
         minimum_retry_interval=60,  # minimum retry interval in seconds
         proxies=None,  # string maps url schemes to the url of the proxies

contrib/opencensus-ext-azure/opencensus/ext/azure/log_exporter/__init__.py

@@ -30,6 +30,7 @@
 )
 from opencensus.ext.azure.common.storage import LocalFileStorage
 from opencensus.ext.azure.common.transport import TransportMixin
+from opencensus.ext.azure.metrics_exporter import statsbeat_metrics
 from opencensus.trace import execution_context
 
 logger = logging.getLogger(__name__)
@@ -61,6 +62,10 @@ def __init__(self, **options):
         self._queue = Queue(capacity=self.options.queue_capacity)
         self._worker = Worker(self._queue, self)
         self._worker.start()
+        # start statsbeat on exporter instantiation
+        statsbeat_metrics.collect_statsbeat_metrics(
+            self.options.instrumentation_key
+        )
 
     def _export(self, batch, event=None):  # pragma: NO COVER
         try:

contrib/opencensus-ext-azure/opencensus/ext/azure/metrics_exporter/__init__.py

@@ -39,8 +39,9 @@
 class MetricsExporter(TransportMixin, ProcessorMixin):
     """Metrics exporter for Microsoft Azure Monitor."""
 
-    def __init__(self, **options):
+    def __init__(self, is_stats=False, **options):
         self.options = Options(**options)
+        self._is_stats = is_stats
         utils.validate_instrumentation_key(self.options.instrumentation_key)
         if self.options.max_batch_size <= 0:
             raise ValueError('Max batch size must be at least 1.')
@@ -131,7 +132,10 @@ def _create_envelope(self, data_point, timestamp, properties):
             tags=dict(utils.azure_monitor_context),
             time=timestamp.isoformat(),
         )
-        envelope.name = "Microsoft.ApplicationInsights.Metric"
+        if self._is_stats:
+            envelope.name = "Statsbeat"
+        else:
+            envelope.name = "Microsoft.ApplicationInsights.Metric"
         data = MetricData(
             metrics=[data_point],
             properties=properties
@@ -157,4 +161,9 @@ def new_metrics_exporter(**options):
                                     producers,
                                     exporter,
                                     interval=exporter.options.export_interval)
+    from opencensus.ext.azure.metrics_exporter import statsbeat_metrics
+    # Stats will track the user's ikey
+    statsbeat_metrics.collect_statsbeat_metrics(
+        exporter.options.instrumentation_key
+    )
     return exporter

contrib/opencensus-ext-azure/opencensus/ext/azure/metrics_exporter/heartbeat_metrics/__init__.py

@@ -0,0 +1,60 @@
+# Copyright 2020, OpenCensus Authors
+#
+# 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 threading
+
+from opencensus.ext.azure.metrics_exporter import MetricsExporter
+from opencensus.ext.azure.metrics_exporter.statsbeat_metrics.statsbeat import (
+    _STATS_CONNECTION_STRING,
+    _STATS_SHORT_EXPORT_INTERVAL,
+    _StatsbeatMetrics,
+)
+from opencensus.metrics import transport
+from opencensus.metrics.export.metric_producer import MetricProducer
+
+_STATSBEAT_METRICS = None
+_STATSBEAT_LOCK = threading.Lock()
+
+
+def collect_statsbeat_metrics(ikey):
+    with _STATSBEAT_LOCK:
+        # Only start statsbeat if did not exist before
+        global _STATSBEAT_METRICS  # pylint: disable=global-statement
+        if _STATSBEAT_METRICS is None:
+            exporter = MetricsExporter(
+                is_stats=True,
+                connection_string=_STATS_CONNECTION_STRING,
+                export_interval=_STATS_SHORT_EXPORT_INTERVAL,  # 15 minutes by default  # noqa: E501
+            )
+            # The user's ikey is the one being tracked
+            producer = _AzureStatsbeatMetricsProducer(
+                instrumentation_key=ikey
+            )
+            _STATSBEAT_METRICS = producer
+            exporter.exporter_thread = \
+                transport.get_exporter_thread([_STATSBEAT_METRICS],
+                                              exporter,
+                                              exporter.options.export_interval)
+
+
+class _AzureStatsbeatMetricsProducer(MetricProducer):
+    """Implementation of the producer of statsbeat metrics.
+
+    Includes Azure attach rate metrics, implemented using gauges.
+    """
+    def __init__(self, instrumentation_key):
+        self._statsbeat = _StatsbeatMetrics(instrumentation_key)
+
+    def get_metrics(self):
+        return self._statsbeat.get_metrics()