AIL-framework/bin/Helper.py

158 lines
6.0 KiB
Python
Executable File

#!/usr/bin/env python2
# -*-coding:UTF-8 -*
"""
Queue helper module
============================
This module subscribe to a Publisher stream and put the received messages
into a Redis-list waiting to be popped later by others scripts.
..note:: Module ZMQ_Something_Q and ZMQ_Something are closely bound, always put
the same Subscriber name in both of them.
"""
import redis
import ConfigParser
import os
import zmq
import time
import json
class PubSub(object):
def __init__(self):
configfile = os.path.join(os.environ['AIL_BIN'], 'packages/config.cfg')
if not os.path.exists(configfile):
raise Exception('Unable to find the configuration file. \
Did you set environment variables? \
Or activate the virtualenv.')
self.config = ConfigParser.ConfigParser()
self.config.read(configfile)
self.redis_sub = False
self.zmq_sub = False
self.subscriber = None
self.publishers = {'Redis': [], 'ZMQ': []}
def setup_subscribe(self, conn_name):
if self.config.has_section(conn_name):
channel = self.config.get(conn_name, 'channel')
else:
channel = conn_name.split('_')[1]
if conn_name.startswith('Redis'):
self.redis_sub = True
r = redis.StrictRedis(
host=self.config.get('RedisPubSub', 'host'),
port=self.config.get('RedisPubSub', 'port'),
db=self.config.get('RedisPubSub', 'db'))
self.subscriber = r.pubsub(ignore_subscribe_messages=True)
self.subscriber.psubscribe(channel)
elif conn_name.startswith('ZMQ'):
self.zmq_sub = True
context = zmq.Context()
self.subscriber = context.socket(zmq.SUB)
self.subscriber.connect(self.config.get(conn_name, 'address'))
self.subscriber.setsockopt(zmq.SUBSCRIBE, channel)
def setup_publish(self, conn_name):
if self.config.has_section(conn_name):
channel = self.config.get(conn_name, 'channel')
else:
channel = conn_name.split('_')[1]
if conn_name.startswith('Redis'):
r = redis.StrictRedis(host=self.config.get('RedisPubSub', 'host'),
port=self.config.get('RedisPubSub', 'port'),
db=self.config.get('RedisPubSub', 'db'))
self.publishers['Redis'].append((r, channel))
elif conn_name.startswith('ZMQ'):
context = zmq.Context()
p = context.socket(zmq.PUB)
p.bind(self.config.get(conn_name, 'address'))
self.publishers['ZMQ'].append((p, channel))
def publish(self, message):
m = json.loads(message)
channel_message = m.get('channel')
for p, channel in self.publishers['Redis']:
if channel_message is None or channel_message == channel:
p.publish(channel, m['message'])
for p, channel in self.publishers['ZMQ']:
if channel_message is None or channel_message == channel:
p.send('{} {}'.format(channel, m['message']))
def subscribe(self):
if self.redis_sub:
for msg in self.subscriber.listen():
if msg.get('data', None) is not None:
yield msg['data']
elif self.zmq_sub:
while True:
msg = self.subscriber.recv()
yield msg.split(' ', 1)[1]
else:
raise Exception('No subscribe function defined')
class Process(object):
def __init__(self, conf_section):
configfile = os.path.join(os.environ['AIL_BIN'], 'packages/config.cfg')
if not os.path.exists(configfile):
raise Exception('Unable to find the configuration file. \
Did you set environment variables? \
Or activate the virtualenv.')
modulesfile = os.path.join(os.environ['AIL_BIN'], 'packages/modules.cfg')
self.config = ConfigParser.ConfigParser()
self.config.read(configfile)
self.modules = ConfigParser.ConfigParser()
self.modules.read(modulesfile)
self.subscriber_name = conf_section
self.pubsub = None
if self.modules.has_section(conf_section):
self.pubsub = PubSub()
else:
raise Exception('Your process has to listen to at least one feed.')
self.r_temp = redis.StrictRedis(
host=self.config.get('RedisPubSub', 'host'),
port=self.config.get('RedisPubSub', 'port'),
db=self.config.get('RedisPubSub', 'db'))
def populate_set_in(self):
# monoproc
src = self.modules.get(self.subscriber_name, 'subscribe')
self.pubsub.setup_subscribe(src)
for msg in self.pubsub.subscribe():
in_set = self.subscriber_name + 'in'
self.r_temp.sadd(in_set, msg)
self.r_temp.hset('queues', self.subscriber_name,
int(self.r_temp.scard(in_set)))
def get_from_set(self):
# multiproc
in_set = self.subscriber_name + 'in'
self.r_temp.hset('queues', self.subscriber_name,
int(self.r_temp.scard(in_set)))
return self.r_temp.spop(in_set)
def populate_set_out(self, msg, channel=None):
# multiproc
msg = {'message': msg}
if channel is not None:
msg.update({'channel': channel})
self.r_temp.sadd(self.subscriber_name + 'out', json.dumps(msg))
def publish(self):
# monoproc
if not self.modules.has_option(self.subscriber_name, 'publish'):
return False
dest = self.modules.get(self.subscriber_name, 'publish')
# We can have multiple publisher
for name in dest.split(','):
self.pubsub.setup_publish(name)
while True:
message = self.r_temp.spop(self.subscriber_name + 'out')
if message is None:
time.sleep(1)
continue
self.pubsub.publish(message)