Simple RaspberryPi B+ with BMP180 and LED on GPIO22 for demonstration of AWS/IOT with MQTT. The following code was modified from the Connecting your RaspberryPi to AWS IoT tutorial.
''' /* * Copyright 2010-2017 Amazon.com, Inc. or its affiliates. All Rights Reserved. * * Licensed under the Apache License, Version 2.0 (the "License"). * You may not use this file except in compliance with the License. * A copy of the License is located at * * http://aws.amazon.com/apache2.0 * * or in the "license" file accompanying this file. This file is distributed * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either * express or implied. See the License for the specific language governing * permissions and limitations under the License. */ ''' from AWSIoTPythonSDK.MQTTLib import AWSIoTMQTTClient import logging import time import argparse import json #import for GPIO Usage on RaspberryPi import RPi.GPIO as GPIO #Pins for LED Example GPIO.setmode(GPIO.BCM) GPIO.setup(22,GPIO.OUT) # Import / Setup BMP Sensor import Adafruit_BMP.BMP085 as BMP085 sensor = BMP085.BMP085() AllowedActions = ['both', 'publish', 'subscribe'] # Custom MQTT message callback # Added Temp info from BMP Sensor and logic to turn on/off led # when temp above 20.2C def customCallback(client, userdata, message): print("Received a new message: ") print(message.payload) Mytemp = json.loads(message.payload) print("MY TEMP IN THE OFFICE: ") print (Mytemp['Temp']) if (Mytemp['Temp'] > 20.2): GPIO.output(22,1) else: GPIO.output(22,0) print("from topic: ") print(message.topic) print("--------------\n\n") # Read in command-line parameters parser = argparse.ArgumentParser() parser.add_argument("-e", "--endpoint", action="store", required=True, dest="host", help="Your AWS IoT custom endpoint") parser.add_argument("-r", "--rootCA", action="store", required=True, dest="rootCAPath", help="Root CA file path") parser.add_argument("-c", "--cert", action="store", dest="certificatePath", help="Certificate file path") parser.add_argument("-k", "--key", action="store", dest="privateKeyPath", help="Private key file path") parser.add_argument("-p", "--port", action="store", dest="port", type=int, help="Port number override") parser.add_argument("-w", "--websocket", action="store_true", dest="useWebsocket", default=False, help="Use MQTT over WebSocket") parser.add_argument("-id", "--clientId", action="store", dest="clientId", default="basicPubSub", help="Targeted client id") parser.add_argument("-t", "--topic", action="store", dest="topic", default="sdk/test/Python", help="Targeted topic") parser.add_argument("-m", "--mode", action="store", dest="mode", default="both", help="Operation modes: %s"%str(AllowedActions)) parser.add_argument("-M", "--message", action="store", dest="message", default="Hello World!", help="Message to publish") args = parser.parse_args() host = args.host rootCAPath = args.rootCAPath certificatePath = args.certificatePath privateKeyPath = args.privateKeyPath port = args.port useWebsocket = args.useWebsocket clientId = args.clientId topic = args.topic if args.mode not in AllowedActions: parser.error("Unknown --mode option %s. Must be one of %s" % (args.mode, str(AllowedActions))) exit(2) if args.useWebsocket and args.certificatePath and args.privateKeyPath: parser.error("X.509 cert authentication and WebSocket are mutual exclusive. Please pick one.") exit(2) if not args.useWebsocket and (not args.certificatePath or not args.privateKeyPath): parser.error("Missing credentials for authentication.") exit(2) # Port defaults if args.useWebsocket and not args.port: # When no port override for WebSocket, default to 443 port = 443 if not args.useWebsocket and not args.port: # When no port override for non-WebSocket, default to 8883 port = 8883 # Configure logging logger = logging.getLogger("AWSIoTPythonSDK.core") logger.setLevel(logging.DEBUG) streamHandler = logging.StreamHandler() formatter = logging.Formatter('%(asctime)s - %(name)s - %(levelname)s - %(message)s') streamHandler.setFormatter(formatter) logger.addHandler(streamHandler) # Init AWSIoTMQTTClient myAWSIoTMQTTClient = None if useWebsocket: myAWSIoTMQTTClient = AWSIoTMQTTClient(clientId, useWebsocket=True) myAWSIoTMQTTClient.configureEndpoint(host, port) myAWSIoTMQTTClient.configureCredentials(rootCAPath) else: myAWSIoTMQTTClient = AWSIoTMQTTClient(clientId) myAWSIoTMQTTClient.configureEndpoint(host, port) myAWSIoTMQTTClient.configureCredentials(rootCAPath, privateKeyPath, certificatePath) # AWSIoTMQTTClient connection configuration myAWSIoTMQTTClient.configureAutoReconnectBackoffTime(1, 32, 20) myAWSIoTMQTTClient.configureOfflinePublishQueueing(-1) # Infinite offline Publish queueing myAWSIoTMQTTClient.configureDrainingFrequency(2) # Draining: 2 Hz myAWSIoTMQTTClient.configureConnectDisconnectTimeout(10) # 10 sec myAWSIoTMQTTClient.configureMQTTOperationTimeout(5) # 5 sec # Connect and subscribe to AWS IoT myAWSIoTMQTTClient.connect() if args.mode == 'both' or args.mode == 'subscribe': myAWSIoTMQTTClient.subscribe(topic, 1, customCallback) time.sleep(2) # Publish to the same topic in a loop forever loopCount = 10 while True: Temp = sensor.read_temperature() print ("TEMP: " + str(Temp)) if args.mode == 'both' or args.mode == 'publish': message = {} message['Temp'] = Temp message['sequence'] = loopCount messageJson = json.dumps(message) myAWSIoTMQTTClient.publish(topic, messageJson, 1) if args.mode == 'publish': print('Published topic %s: %s\n' % (topic, messageJson)) loopCount += 1 time.sleep(2) |
python basicPubSub.py -e YOURAWSIOTSHADOW.us-east-1.amazonaws.com -r root-CA.crt -c MyRasp.cert.pem -k MyRasp.private.key |
I am still learning the AWS IoT basics and have posted this as a reminder to myself as to how it got setup. I planned on refining this into tutorial but really did not see the need as the AWS Samples are pretty good. Connecting your RaspberryPi to AWS IoT is your best place to start.