Total cpu utilization of running app engine flexible instances - google-app-engine

Question

I need to make decisions in an external system based on the current CPU utilization of my App Engine Flexible service. I can see the exact values / metrics I need to use in the dashboard charting in my Google Cloud Console, but I don't see a direct, easy way to get this information from something like a gcloud command.
I also need to know the count of running instances, but I think I can use gcloud app instances list -s default to get a list of my running instances in the default service, and then I can use a count of lines approach to get this info easily. I intend to make a python function which returns a tuple like (instance_count, cpu_utilization).
I'd appreciate if anyone can direct me to an easy way to get this. I am currently exploring the StackDriver Monitoring service to get this same information, but as of now it is looking super-complicated to me.

Answer 1

You can use the gcloud app instances list -s default command to get the running instances list, as you said. To retrieve CPU utilization, have a look on this Python Client for Stackdriver Monitoring. To list available metric types:
from google.cloud import monitoring
client = monitoring.Client()
for descriptor in client.list_metric_descriptors():
print(descriptor.type)
Metric descriptors are described here. To display utilization across your GCE instances during the last five minutes:
metric = 'compute.googleapis.com/instance/cpu/utilization'
query = client.query(metric, minutes=5)
print(query.as_dataframe())
Do not forget to add google-cloud-monitoring==0.28.1 to “requirements.txt” before installing it.
Check this code that locally runs for me:
import logging
from flask import Flask
from google.cloud import monitoring as mon
app = Flask(__name__)
#app.route('/')
def list_metric_descriptors():
"""Return all metric descriptors"""
# Instantiate client
client = mon.Client()
for descriptor in client.list_metric_descriptors():
print(descriptor.type)
return descriptor.type
#app.route('/CPU')
def cpuUtilization():
"""Return CPU utilization"""
client = mon.Client()
metric = 'compute.googleapis.com/instance/cpu/utilization'
query = client.query(metric, minutes=5)
print(type(query.as_dataframe()))
print(query.as_dataframe())
data=str(query.as_dataframe())
return data
#app.errorhandler(500)
def server_error(e):
logging.exception('An error occurred during a request.')
return """
An internal error occurred: <pre>{}</pre>
See logs for full stacktrace.
""".format(e), 500
if __name__ == '__main__':
# This is used when running locally. Gunicorn is used to run the
# application on Google App Engine. See entrypoint in app.yaml.
app.run(host='127.0.0.1', port=8080, debug=True)