prometheus backfill test

docker-compose.yml

version: "2.1"

services:
  prom:
    image: prom/prometheus
    environment:
      - TZ=$TZ
    volumes:
      - ./prom.yml:/etc/prometheus/prometheus.yml
    ports:
      - 9090:9090
  source:
    image: python:3.6
    environment:
      - TX=$TZ
    volumes:
      - .:/app
    ports:
      - 5000:5000
    command: bash -c 'pip install flask pendulum && python -u /app/main.py'

main.py

from random import randint
from textwrap import dedent
import sys

from flask import Flask
import pendulum


app = Flask(__name__)

NOW = pendulum.now()
START_COUNTER = int((NOW - pendulum.Interval(hours=2)).timestamp())

COUNTER = (c for c in range(START_COUNTER, int(NOW.timestamp()), 15))

result = ""
result_tmpl = dedent(
    """
    # HELP test_total Testmetric
    # TYPE test_total gauge
    test_total {0} {1}
    """)
TIMESTAMP = None

@app.route('/metrics')
def metrics():
    now = None
    global COUNTER
    global TIMESTAMP
    global result
    try:
        TIMESTAMP = next(COUNTER)
    except StopIteration:
        now = int(pendulum.now().timestamp())

    if now and now != TIMESTAMP:
        TIMESTAMP = now
        result = result_tmpl.format(randint(1, 50), TIMESTAMP * 1000)
    elif now is None:
        result = result_tmpl.format(randint(1, 50), TIMESTAMP * 1000)
        print(TIMESTAMP, file=sys.stderr)
    return result


if __name__ == '__main__':
    app.run(debug=True, host="0.0.0.0")

prom.yml

global:
  scrape_interval:  75ms

scrape_configs:
  - job_name: 'test'
    static_configs:
      - targets: ['source:5000']