net_device_usage_samples.py

"""
This file contains a sample using the functions in the utils module
to poll the net_device_usage_samples endpoint for all new usage samples.
The sample process_usage_sample() function just prints any new metrics to the
console, but you can replace it with anything you want (e.g., write the info
 to your database, send it to a log server)
"""
from pprint import pprint
from datetime import datetime, timedelta
from time import sleep
from monitoring.utils.session import APISession
from monitoring.utils.timeuuid_endpoint import (get_filtered)
from monitoring.utils.credentials import get_credentials
from monitoring.utils.logger import get_logger

POLL_INTERVAL = 3600  # 1 hour; adjust to your needs
ID_BATCH_LIMIT = 100  # we are allowed to request samples for at most 100 IDs at a time
POLL_START_TIME = datetime.utcnow() - timedelta(hours=1)


def poll_for_new_samples(session=None, ids=[]):
    endpoint = 'net_device_usage_samples'

    start_ts = POLL_START_TIME
    last_uuid = None

    while True:
        batch_idx = 0

        while batch_idx < len(ids):
            batch_ids = ids[batch_idx:ID_BATCH_LIMIT]
            if not last_uuid and start_ts:
                recs = get_filtered(endpoint=endpoint, session=session,
                                    after_time=start_ts,
                                    order_by=['created_at_timeuuid'],
                                    net_device_ids=batch_ids)
            else:
                recs = get_filtered(endpoint=endpoint, session=session,
                                    after_uuid=last_uuid,
                                    order_by=['created_at_timeuuid'],
                                    net_device_ids=batch_ids)
            for r in recs:
                process_usage_sample(r)
                last_uuid = r['created_at_timeuuid']
            batch_idx += len(batch_ids)

        sleep(POLL_INTERVAL)


def process_usage_sample(s):
    """Do whatever you need to with a single usage_sample."""
    pprint(s)


if __name__ == '__main__':
    logger = get_logger()
    try:
        with APISession(**get_credentials(), logger=logger) as s:
            # get a list of all my net device ids:
            recs = s.get(endpoint='net_devices', filter={'fields': 'id'})
            ids = [rec['id'] for rec in recs]

            # poll them
            poll_for_new_samples(s, ids)
    except Exception as x:
        logger.exception('Unexpected exception')