flask_redis_page_visit_counter_with_retry.py

1import time
2
3import redis
4from flask import Flask
5
6app = Flask(__name__)
7cache = redis.Redis(host='redis', port=6379)
8
9def get_hit_count():
10    retries = 5
11    while True:
12        try:
13            return cache.incr('hits')
14        except redis.exceptions.ConnectionError as exc:
15            if retries == 0:
16                raise exc
17            retries -= 1
18            time.sleep(0.5)
19
20@app.route('/')
21def hello():
22    count = get_hit_count()
23    return 'Hello World! I have been seen {} times.\n'.format(count)