158 lines
4.7 KiB
Python
158 lines
4.7 KiB
Python
import json
|
|
import logging
|
|
import random
|
|
import string
|
|
import redis
|
|
import time
|
|
|
|
from redlock import Redlock
|
|
from queue import Queue
|
|
|
|
logger = logging.getLogger(__name__)
|
|
|
|
ONE_YEAR = 3600 * 24 * 365
|
|
|
|
|
|
def generate_token(n: int):
|
|
'''Generate a random ASCII token of length n'''
|
|
# uses os.urandom()
|
|
rng = random.SystemRandom()
|
|
return ''.join([rng.choice(string.ascii_letters + string.digits) for i in range(n)])
|
|
|
|
|
|
def generate_token_data():
|
|
'''Generate screen token data for storing'''
|
|
token = generate_token(10)
|
|
now = time.time()
|
|
return {'token': token, 'created': now, 'expires': now + ONE_YEAR}
|
|
|
|
|
|
def check_token(token: str, remote_addr: str, data: dict):
|
|
'''Check whether the given screen token is valid, raises exception if not'''
|
|
now = time.time()
|
|
if data and now < data['expires'] and data.get('remote_addr', remote_addr) == remote_addr:
|
|
data['remote_addr'] = remote_addr
|
|
return data
|
|
else:
|
|
raise ValueError('Invalid token')
|
|
|
|
|
|
class AbstractStore:
|
|
|
|
def get_cluster_ids(self):
|
|
return self.get('cluster-ids') or []
|
|
|
|
def set_cluster_ids(self, cluster_ids: set):
|
|
self.set('cluster-ids', list(sorted(cluster_ids)))
|
|
|
|
def get_cluster_status(self, cluster_id: str) -> dict:
|
|
return self.get('clusters:{}:status'.format(cluster_id)) or {}
|
|
|
|
def set_cluster_status(self, cluster_id: str, status: dict):
|
|
self.set('clusters:{}:status'.format(cluster_id), status)
|
|
|
|
def get_cluster_data(self, cluster_id: str) -> dict:
|
|
return self.get('clusters:{}:data'.format(cluster_id)) or {}
|
|
|
|
def set_cluster_data(self, cluster_id: str, data: dict):
|
|
self.set('clusters:{}:data'.format(cluster_id), data)
|
|
|
|
|
|
class MemoryStore(AbstractStore):
|
|
'''Memory-only backend, mostly useful for local debugging'''
|
|
|
|
def __init__(self):
|
|
self._data = {}
|
|
self._queues = []
|
|
self._screen_tokens = {}
|
|
|
|
def set(self, key, value):
|
|
self._data[key] = value
|
|
|
|
def get(self, key):
|
|
return self._data.get(key)
|
|
|
|
def acquire_lock(self):
|
|
# no-op for memory store
|
|
return 'fake-lock'
|
|
|
|
def release_lock(self, lock):
|
|
# no op for memory store
|
|
pass
|
|
|
|
def publish(self, event_type, event_data):
|
|
for queue in self._queues:
|
|
queue.put((event_type, event_data))
|
|
|
|
def listen(self):
|
|
queue = Queue()
|
|
self._queues.append(queue)
|
|
try:
|
|
while True:
|
|
item = queue.get()
|
|
yield item
|
|
finally:
|
|
self._queues.remove(queue)
|
|
|
|
def create_screen_token(self):
|
|
data = generate_token_data()
|
|
token = data['token']
|
|
self._screen_tokens[token] = data
|
|
return token
|
|
|
|
def redeem_screen_token(self, token: str, remote_addr: str):
|
|
data = self._screen_tokens.get(token)
|
|
data = check_token(token, remote_addr, data)
|
|
self._screen_tokens[token] = data
|
|
|
|
|
|
class RedisStore(AbstractStore):
|
|
'''Redis-based backend for deployments with replicas > 1'''
|
|
|
|
def __init__(self, url: str):
|
|
logger.info('Connecting to Redis on {}..'.format(url))
|
|
self._redis = redis.StrictRedis.from_url(url)
|
|
self._redlock = Redlock([url])
|
|
|
|
def set(self, key, value):
|
|
self._redis.set(key, json.dumps(value, separators=(',', ':')))
|
|
|
|
def get(self, key):
|
|
value = self._redis.get(key)
|
|
if value:
|
|
return json.loads(value.decode('utf-8'))
|
|
|
|
def acquire_lock(self):
|
|
return self._redlock.lock('update', 10000)
|
|
|
|
def release_lock(self, lock):
|
|
self._redlock.unlock(lock)
|
|
|
|
def publish(self, event_type, event_data):
|
|
self._redis.publish('default', '{}:{}'.format(event_type, json.dumps(event_data, separators=(',', ':'))))
|
|
|
|
def listen(self):
|
|
p = self._redis.pubsub()
|
|
p.subscribe('default')
|
|
for message in p.listen():
|
|
if message['type'] == 'message':
|
|
event_type, data = message['data'].decode('utf-8').split(':', 1)
|
|
yield (event_type, json.loads(data))
|
|
|
|
def create_screen_token(self):
|
|
'''Generate a new screen token and store it in Redis'''
|
|
data = generate_token_data()
|
|
token = data['token']
|
|
self._redis.set('screen-tokens:{}'.format(token), json.dumps(data))
|
|
return token
|
|
|
|
def redeem_screen_token(self, token: str, remote_addr: str):
|
|
'''Validate the given token and bind it to the IP'''
|
|
redis_key = 'screen-tokens:{}'.format(token)
|
|
data = self._redis.get(redis_key)
|
|
if not data:
|
|
raise ValueError('Invalid token')
|
|
data = json.loads(data.decode('utf-8'))
|
|
data = check_token(token, remote_addr, data)
|
|
self._redis.set(redis_key, json.dumps(data))
|