prometheus backfill test

docker-compose.yml

version: "2.1"

services:
  prom:
    image: prom/prometheus
    volumes:
      - ./prom.yml:/etc/prometheus/prometheus.yml
    ports:
      - 9090:9090
  source:
    image: python:3.6
    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__)


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


@app.route('/metrics')
def metrics():
    global COUNTER
    COUNTER += 15
    now = int(pendulum.now().timestamp())
    print(COUNTER, now - COUNTER, file=sys.stderr)
    if (now - COUNTER) <= 0:
        return ""
    return dedent(f"""\
        # HELP test_total Testmetric
        # TYPE test_total gauge
        test_total {randint(1, 50)} {COUNTER}
    """)


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']