server-mq.py

#!/usr/bin/env python
#from pyfirmata import Arduino, util
import pika

try:
    credentials = pika.PlainCredentials('guest', 'guest')
    # Establishes the Connection with the RabbitMQ and Declares the Channel
    connection = pika.BlockingConnection(pika.ConnectionParameters('localhost', 5672, '/', credentials))  # RabbitMQ Connection
    channel = connection.channel()  # RabbitMQ Channel in Connection

except Exception, e:
	print str(e)


# Set the Queue Name
queue_name = "message_broker"

# Set the Queue in the Channel
channel.queue_declare(queue=queue_name)

# Set the Arduino Board
#board = Arduino('/dev/ttyUSB0')
# Set the Digital GPIO 13 to Output
#pin_d13 = board.get_pin('d:13:o')


# Define the SET 1 (one) function to MongoDB
def setD13_on(json_string):
#    try:
#        pin_d13.write(1)

#    except Exception, e:
#        print str(e)

    return json_string


# Define the SET 0 (zero) function to MongoDB
def setD13_off(json_string):
#    try:
#        pin_d13.write(0)

#    except Exception, e:
#        print str(e)

    return json_string

# The Request is Received, it is Processed and Send the Response
def on_request(ch, method, props, body):
    json_string = str(body)

    if json_string.find('on') != -1:
        responseIn = {"setD13_on": setD13_on(json_string)}

        print(" [.] Set D13: %s " % responseIn['setD13_on'])

    else:
        responseIn = {"setD13_off": setD13_off(json_string)}

        print(" [.] Set D13: %s " % responseIn['setD13_off'])


    # responseIn['_id'] = random_gen()

    ch.basic_publish(exchange='',
                     routing_key=props.reply_to,
                     properties=pika.BasicProperties(correlation_id = \
                                                         props.correlation_id),
                     body="; ".join(responseIn))
    ch.basic_ack(delivery_tag = method.delivery_tag)


# Run more than one Process in Server and Load Balancing
channel.basic_qos(prefetch_count=1)
channel.basic_consume(queue=queue_name, on_message_callback=on_request)


print(" [x] Awaiting RPC requests")
channel.start_consuming()