Add alarm creation to celery script OPS-2545

util/jenkins/check-celery-queues.py

@@ -35,19 +35,32 @@ class RedisWrapper(object):
 
 class CwBotoWrapper(object):
     def __init__(self):
-        self.cw = boto3.client('cloudwatch')
+        self.client = boto3.client('cloudwatch')
 
     @backoff.on_exception(backoff.expo,
                           (botocore.exceptions.ClientError),
                           max_tries=max_tries)
     def list_metrics(self, *args, **kwargs):
-        return self.cw.list_metrics(*args, **kwargs)
+        return self.client.list_metrics(*args, **kwargs)
 
     @backoff.on_exception(backoff.expo,
                           (botocore.exceptions.ClientError),
                           max_tries=max_tries)
     def put_metric_data(self, *args, **kwargs):
-        return self.cw.put_metric_data(*args, **kwargs)
+        return self.client.put_metric_data(*args, **kwargs)
+
+    @backoff.on_exception(backoff.expo,
+                          (botocore.exceptions.ClientError),
+                          max_tries=max_tries)
+    def describe_alarms_for_metric(self, *args, **kwargs):
+        return self.client.describe_alarms_for_metric(*args, **kwargs)
+
+    @backoff.on_exception(backoff.expo,
+                          (botocore.exceptions.ClientError),
+                          max_tries=max_tries)
+    def put_metric_alarm(self, *args, **kwargs):
+        return self.client.put_metric_alarm(*args, **kwargs)
+
 
 @click.command()
 @click.option('--host', '-h', default='localhost',
@@ -58,22 +71,28 @@ class CwBotoWrapper(object):
               help="Deployment (i.e. edx or edge)")
 @click.option('--max-metrics', default=30,
               help='Maximum number of CloudWatch metrics to publish')
-def check_queues(host, port, environment, deploy, max_metrics):
+@click.option('--threshold', default=50,
+              help='Maximum queue length before alarm notification is sent')
+@click.option('--sns-arn', '-s', help='ARN for SNS alert topic')
+def check_queues(host, port, environment, deploy, max_metrics, threshold,
+                 sns_arn):
     timeout = 1
     namespace = "celery/{}-{}".format(environment, deploy)
-    r = RedisWrapper(host=host, port=port, socket_timeout=timeout,
-                     socket_connect_timeout=timeout)
-    cw = CwBotoWrapper()
+    redis_client = RedisWrapper(host=host, port=port, socket_timeout=timeout,
+                                socket_connect_timeout=timeout)
+    cloudwatch = CwBotoWrapper()
     metric_name = 'queue_length'
     dimension = 'queue'
-    response = cw.list_metrics(Namespace=namespace, MetricName=metric_name,
-                               Dimensions=[{'Name': dimension}])
+    response = cloudwatch.list_metrics(Namespace=namespace,
+                                       MetricName=metric_name,
+                                       Dimensions=[{'Name': dimension}])
     existing_queues = []
     for m in response["Metrics"]:
         existing_queues.extend(
             [d['Value'] for d in m["Dimensions"] if d['Name'] == dimension])
 
-    redis_queues = set([k.decode() for k in r.keys() if r.type(k) == b'list'])
+    redis_queues = set([k.decode() for k in redis_client.keys()
+                        if redis_client.type(k) == b'list'])
 
     all_queues = existing_queues + list(
         set(redis_queues).difference(existing_queues)
@@ -95,10 +114,34 @@ def check_queues(host, port, environment, deploy, max_metrics):
                 "Name": dimension,
                 "Value": queue
             }],
-            'Value': r.llen(queue)
+            'Value': redis_client.llen(queue)
         })
 
-    cw.put_metric_data(Namespace=namespace, MetricData=metric_data)
+    cloudwatch.put_metric_data(Namespace=namespace, MetricData=metric_data)
+
+    for queue in queues:
+        dimensions = [{'Name': dimension, 'Value': queue}]
+        period = 300
+        evaluation_periods = 1
+        comparison_operator = "GreaterThanThreshold"
+        treat_missing_data = "missing"
+        statistic = "Maximum"
+        actions = [sns_arn]
+        alarm_name = "{} queue length over threshold".format(queue)
+
+        # Always create/configure alert to keep config up to date
+        cloudwatch.put_metric_alarm(AlarmName=alarm_name,
+                                    AlarmDescription=alarm_name,
+                                    Namespace=namespace,
+                                    MetricName=metric_name,
+                                    Dimensions=dimensions,
+                                    Period=period,
+                                    EvaluationPeriods=evaluation_periods,
+                                    TreatMissingData=treat_missing_data,
+                                    Threshold=threshold,
+                                    ComparisonOperator=comparison_operator,
+                                    Statistic=statistic,
+                                    AlarmActions=actions)
 
 
 if __name__ == '__main__':