[cluster-agent] Add new metric for SSI gradual rollout (DataDog#21599)

* Add admission_webhooks.image_resolution_attempts telemetry to cluster agent

* Add missing count in fixture

* Add changelog

* Add missing type in metadata

* Correctly sort metadata

* Remove commas and update description in metadata

* Add missing metadata

* Update datadog_cluster_agent/changelog.d/21599.added

Author: erikayasuda

datadog_cluster_agent/changelog.d/21599.added

@@ -0,0 +1 @@
+Add new metric for SSI gradual rollout

datadog_cluster_agent/datadog_checks/datadog_cluster_agent/check.py

@@ -22,6 +22,7 @@
     'admission_webhooks_reconcile_success': 'admission_webhooks.reconcile_success',
     'admission_webhooks_response_duration': 'admission_webhooks.response_duration',
     'admission_webhooks_webhooks_received': 'admission_webhooks.webhooks_received',
+    'admission_webhooks_image_resolution_attempts': 'admission_webhooks.image_resolution_attempts',
     'autoscaling_workload_autoscaler_conditions': 'autoscaling.workload.autoscaler_conditions',
     'autoscaling_workload_horizontal_scaling_actions': 'autoscaling.workload.horizontal_scaling_actions',
     'autoscaling_workload_horizontal_scaling_applied_replicas': 'autoscaling.workload.horizontal_scaling_applied_replicas',  # noqa: E501

datadog_cluster_agent/metadata.csv

@@ -4,6 +4,7 @@ datadog.cluster_agent.admission_webhooks.cws_exec_mutation_attempts,count,,,,Num
 datadog.cluster_agent.admission_webhooks.cws_pod_mutation_attempts,count,,,,Number of CWS pod mutation attempts by reason and status,0,datadog_cluster_agent,cws pod mutation attempts,,
 datadog.cluster_agent.admission_webhooks.cws_response_duration.count,count,,,,CWS mutating webhook response duration count,0,datadog_cluster_agent,cws response duration count,,
 datadog.cluster_agent.admission_webhooks.cws_response_duration.sum,count,,,,CWS mutating webhook response duration sum,0,datadog_cluster_agent,cws response duration sum,,
+datadog.cluster_agent.admission_webhooks.image_resolution_attempts,count,,,,Number of image resolution attempts for gradual rollout,0,datadog_cluster_agent,image resolution attempts,,
 datadog.cluster_agent.admission_webhooks.library_injection_attempts,count,,,,Number of library injection attempts by language,0,datadog_cluster_agent,library injection attempts,,
 datadog.cluster_agent.admission_webhooks.library_injection_errors,count,,,,Number of library injection failures by language,0,datadog_cluster_agent,library injection errors,,
 datadog.cluster_agent.admission_webhooks.mutation_attempts,gauge,,,,Number of pod mutation attempts by mutation type,0,datadog_cluster_agent,admission webhooks mutation attempts,,

datadog_cluster_agent/tests/fixtures/metrics.txt

@@ -40,6 +40,9 @@ admission_webhooks_response_duration_count 108
 # HELP admission_webhooks_webhooks_received Number of webhook requests received.
 # TYPE admission_webhooks_webhooks_received gauge
 admission_webhooks_webhooks_received 300
+# HELP admission_webhooks_image_resolution_attempts Number of image resolution attempts
+# TYPE admission_webhooks_image_resolution_attempts counter
+admission_webhooks_image_resolution_attempts{registry="gcr.io/datadoghq",repository="dd-lib-python-init",digest_resolution="enabled",outcome="sha256:test"} 1
 # HELP aggregator__dogstatsd_contexts Count the number of dogstatsd contexts in the aggregator
 # TYPE aggregator__dogstatsd_contexts gauge
 aggregator__dogstatsd_contexts 1

datadog_cluster_agent/tests/test_datadog_cluster_agent.py

@@ -32,6 +32,7 @@
     'admission_webhooks.response_duration.count',
     'admission_webhooks.response_duration.sum',
     'admission_webhooks.webhooks_received',
+    'admission_webhooks.image_resolution_attempts',
     'aggregator.flush',
     'aggregator.processed',
     'api_requests',