52 lines
1.8 KiB
Python
52 lines
1.8 KiB
Python
import requests
|
|
import threading
|
|
import redis
|
|
from flask import make_response, abort
|
|
|
|
|
|
class ImgProxyCache(object):
|
|
def __init__(self, redis_uri='redis://', timeout=1, expire=60*60*24,
|
|
prefix='img_proxy'):
|
|
self.redis = redis.StrictRedis.from_url(redis_uri)
|
|
self.timeout = timeout
|
|
self.expire = expire
|
|
self.prefix = prefix
|
|
self.redis.client_setname('img_proxy')
|
|
|
|
def key(self, keytype, url):
|
|
return '{prefix}:{keytype}:{url}'.format(
|
|
prefix=self.prefix,
|
|
keytype=keytype,
|
|
url=url)
|
|
|
|
def fetch_and_cache(self, url):
|
|
resp = requests.get(url)
|
|
if(resp.status_code != 200):
|
|
return
|
|
mime = resp.headers.get('content-type', 'application/octet-stream')
|
|
self.redis.set(self.key('mime', url),
|
|
mime, px=self.expire*1000)
|
|
self.redis.set(self.key('body', url),
|
|
resp.content, px=self.expire*1000)
|
|
|
|
def respond(self, url):
|
|
x_imgproxy_cache = 'HIT'
|
|
mime = self.redis.get(self.key('mime', url))
|
|
body = self.redis.get(self.key('body', url))
|
|
if not body or not mime:
|
|
x_imgproxy_cache = 'MISS'
|
|
if self.redis.set(
|
|
self.key('lock', url), 1, nx=True, ex=10*self.timeout):
|
|
t = threading.Thread(target=self.fetch_and_cache, args=(url,))
|
|
t.start()
|
|
t.join(self.timeout)
|
|
mime = self.redis.get(self.key('mime', url))
|
|
body = self.redis.get(self.key('body', url))
|
|
if not body or not mime:
|
|
return abort(404)
|
|
|
|
resp = make_response(body, 200)
|
|
resp.headers.set('content-type', mime)
|
|
resp.headers.set('x-imgproxy-cache', x_imgproxy_cache)
|
|
return resp
|