sudo apt-get install python3-pip
sudo python3 -m pip install pika --upgrade
Under Documents folder create two files
Click to show the picture
#!/usr/bin/env python
import pika
import sys
connection = pika.BlockingConnection(
pika.ConnectionParameters(host='localhost'))
channel = connection.channel()
channel.exchange_declare(exchange='topic_logs', exchange_type='topic')
routing_key = sys.argv[1] if len(sys.argv) > 2 else 'anonymous.info'
message = ' '.join(sys.argv[2:]) or 'Hello World!'
channel.basic_publish(
exchange='topic_logs', routing_key=routing_key, body=message)
print(" [x] Sent %r:%r" % (routing_key, message))
connection.close()
#!/usr/bin/env python
import pika, sys, os
def main():
connection = pika.BlockingConnection(
pika.ConnectionParameters(host='localhost'))
channel = connection.channel()
channel.exchange_declare(exchange='topic_logs', exchange_type='topic')
result = channel.queue_declare(queue='', exclusive=True)
queue_name = result.method.queue
binding_keys = sys.argv[1:]
if not binding_keys:
sys.stderr.write("Usage: %s [binding_key]...\n" % sys.argv[0])
sys.exit(1)
for binding_key in binding_keys:
channel.queue_bind(
exchange='topic_logs', queue=queue_name, routing_key=binding_key)
print(' [*] Waiting for logs. To exit press CTRL+C')
def callback(ch, method, properties, body):
print(" [x] %r:%r" % (method.routing_key, body.decode()))
channel.basic_consume(
queue=queue_name, on_message_callback=callback, auto_ack=True)
channel.start_consuming()
if __name__ == '__main__':
try:
main()
except KeyboardInterrupt:
print('Interrupted')
try:
sys.exit(0)
except SystemExit:
os._exit(0)
- in the first terminal run the commands
cd Documents
sudo python receive_logs_topic.py "kern.*"
- in the second terminal run the commands
cd Documents
sudo python receive_logs_topic.py "*.critical"
- in the third terminal run the commands
cd Documents
sudo python receive_logs_topic.py "*.critical"
- in the fourth terminal run the commands
cd Documents
sudo python emit_log_topic.py "kern.critical" "A critical kernel error 1"
sudo python emit_log_topic.py "kern.critical" "A critical kernel error 2"
Click to show the picture
- We get the same functions as above (as for Topics)
- but instead of a dot-separated list of words (like "stock.usd.nyse" or "*.xxx" or "#.yyy")
- we define the filter as a list of routing keys, combined by the operator "OR":
foreach(var severity in args)
{
channel.QueueBind(queue: queueName,
exchange: "direct_logs",
routingKey: severity);
}