如何通过 MQTT 从 lambda 函数接收回消息？

Question

让我向您介绍我的问题，首先我必须说我是 AWS 和 MQTT 的新手，我的意思是（不要生我的气），我的问题：我想通过 MQTT 发布客户端向 AWS IoT/Lambda 发送一个简单的 JSON {'petition':'Hola', 'n':0}，一旦发布，lambda 函数必须发回 JSON 消息 {'petition': 'Mundo', 'n ': 0} 并且必须执行 10 次。当您发布消息时，代码工作正常，但没有收到任何消息。我需要帮助来解决它。

这是squema：

设备 ---> MQTT ---> IoT SQL SENTENCE ---> AWS LAMBDA

设备

注意：设备在 linux 终端中运行，消息必须以某种方式出现在屏幕上。

AWS Lambda 处理程序

import json

def lambda_handler(event, context):
    # TODO implement
    data={}
    data["petition"]="Mundo"
    data["n"]=event["n"]
    mensaje = event['petition']
    if mensaje =='Hola':
        envio=json.dumps(data)
        return data
    else:
        return 'nada encontrado'

物联网 SQL 语句

SELECT * FROM 'Hello_World'

注意：以上 2 个是使用 lambda 函数服务实现的。

设备代码

import paho.mqtt.client as paho
import os
import socket
import ssl
import time
import json



def on_connect(client, userdata, flags, rc):
    print("Connection returned result: " + str(rc) )
    # Subscribing in on_connect() means that if we lose the connection and
    # reconnect then subscriptions will be renewed.

def on_message(client, userdata, msg):
    print("topic: "+msg.topic)
    print("payload: "+str(msg.payload))
    data=json.loads(msg.payload)
    
    if data["n"]<9 and data["petition"]=="Mundo":
        data["petition"] = "Hola"
        data["n"] = n+1
        envio=json.dumps(data)
        mqttc.publish(thingName, envio)
        time.sleep(4)

def on_publish(client,userdata,missatge):           #create function for callback
    print("data published \n")

print "Create client instance"
mqttc = paho.Client()
mqttc.on_connect = on_connect
mqttc.on_publish = on_publish    
mqttc.on_message = on_message

#mqttc.on_log = on_log
data={}
awshost = "a20u2bg4i3u0uq.iot.eu-west-2.amazonaws.com"
awsport = 8883
clientId = "39cfba3c326847909aa5f4544211f4a4"
thingName = "Hello_World"
caPath = "/#/rootCA.pem"
certPath = "/#/3218b320c9-certificate.pem.crt"
keyPath = "/#/3218b320c9-private.pem.key"

mqttc.tls_set(caPath, certfile=certPath, keyfile=keyPath, cert_reqs=ssl.CERT_REQUIRED, tls_version=ssl.PROTOCOL_TLSv1_2, ciphers=None)
print "connecting to browser"
mqttc.connect(awshost, awsport, keepalive=60)

mqttc.loop_start()
time.sleep(2)
print"subscribing...."
mqttc.subscribe(thingName)
print"subscribed"
time.sleep(2)

data["petition"]="Hola"
data["n"]=0
envio=json.dumps(data)
print(envio)
print "Sending..."
mqttc.publish(thingName, envio)

time.sleep(4)
print "Sent"


mqttc.disconnect()
mqttc.loop_stop()

Answer 1

我真的只想在 API Gateway 中为您的 Lambda 回调设置一个 API 调用。