将 Raspberry Pi Pico W 连接到 AWS IoT Core

Question

我正在尝试将 Raspberry Pi Pico W 连接到 AWS IoT Core 以发送传感器数据。我已经安装了 umqtt.simple 库并遵循了一些在线指南，但在处理证书和建立连接时遇到错误。

我的目标是建立安全连接，并希望获得有关代码片段或实现此目标的最佳实践的任何帮助。

具体来说，我不确定：

如何正确读取和使用下载的证书和私钥文件。 使用 umqtt.simple 建立连接并启用安全通信的语法。 预先感谢您的帮助！

这是我用来建立连接的代码。

# Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
# SPDX-License-Identifier: MIT-0

# AWS IoT Core - RPi Pico W Demo

# Required imports
import time
import machine
import network
import ujson
from umqtt.simple import MQTTClient

[code][code][code]
###############################################################################
### START CODE MODIFICATION ###################################################
###############################################################################

# Wifi Name / SSID
SSID = b'<your wifi network name>'
# Wifi Password
PASS = b'<your wifi password>'

# AWS ThingName is used for the Client ID (Best Practice). Example: RaspberryPiPicoW
CLIENT_ID = b'RaspberryPiPicoW'
# AWS Endpoint (Refer to "Creating a Thing in AWS IoT Core" step 13)
AWS_ENDPOINT = b'<your IoT Endpoint value here>'

###############################################################################
### END CODE MODIFICATION #####################################################
###############################################################################


# AWS IoT Core publish topic
PUB_TOPIC = b'/' + CLIENT_ID + '/temperature'
# AWS IoT Core subscribe  topic
SUB_TOPIC = b'/' + CLIENT_ID + '/light'


# Reading Thing Private Key and Certificate into variables for later use
with open('/certs/key.der', 'rb') as f:
    DEV_KEY = f.read()
# Thing Certificate
with open('/certs/cert.der', 'rb') as f:
    DEV_CRT = f.read()


# Define light (Onboard Green LED) and set its default state to off
light = machine.Pin("LED", machine.Pin.OUT)
light.off()


# Wifi Connection Setup
def wifi_connect():
    print('Connecting to wifi...')
    wlan = network.WLAN(network.STA_IF)
    wlan.active(True)
    wlan.connect(SSID, PASS)
    while wlan.isconnected() == False:
        light.on()
        print('Waiting for connection...')
        time.sleep(0.5)
        light.off()
        time.sleep(0.5)
    print('Connection details: %s' % str(wlan.ifconfig()))


# Callback function for all subscriptions
def mqtt_subscribe_callback(topic, msg):
    print("Received topic: %s message: %s" % (topic, msg))
    if topic == SUB_TOPIC:
        mesg = ujson.loads(msg)
        if 'state' in mesg.keys():
            if mesg['state'] == 'on' or mesg['state'] == 'ON' or mesg['state'] == 'On':
                light.on()
                print('Light is ON')
            else:
                light.off()
                print('Light is OFF')


# Read current temperature from RP2040 embeded sensor
def get_rpi_temperature():
    sensor = machine.ADC(4)
    voltage = sensor.read_u16() * (3.3 / 65535)
    temperature = 27 - (voltage - 0.706) / 0.001721
    return temperature


# Connect to wifi
wifi_connect()

# Set AWS IoT Core connection details
mqtt = MQTTClient(
    client_id=CLIENT_ID,
    server=AWS_ENDPOINT,
    port=8883,
    keepalive=5000,
    ssl=True,
    ssl_params={'key':DEV_KEY, 'cert':DEV_CRT, 'server_side':False})

# Establish connection to AWS IoT Core
mqtt.connect()

# Set callback for subscriptions
mqtt.set_callback(mqtt_subscribe_callback)

# Subscribe to topic
mqtt.subscribe(SUB_TOPIC)


# Main loop - with 5 sec delay
while True:
    # Publisg the temperature
    message = b'{"temperature":%s, "temperature_unit":"Degrees Celsius"}' % get_rpi_temperature()
    print('Publishing topic %s message %s' % (PUB_TOPIC, message))
    # QoS Note: 0=Sent zero or more times, 1=Sent at least one, wait for PUBACK
    # See https://docs.aws.amazon.com/iot/latest/developerguide/mqtt.html
    mqtt.publish(topic=PUB_TOPIC, msg=message, qos=0)

    # Check subscriptions for message
    mqtt.check_msg()
    time.sleep(5)
 

我使用上面的代码连接我的树莓派 Pico W，将其连接到 AWS IoT 核心。该代码一直有效，直到它帮助我连接到 WiFi 的部分为止。但一旦到达与 IoT 核心建立连接的代码，它就会停止工作。它给出以下错误。

回溯（最近一次调用最后一次）： 文件“”，第 99 行，位于 类型错误：意外的关键字参数“ssl_params”

Answer 1

根据Micropython核心库官方存储库，

class MQTTClient:
    def __init__(
        self,
        client_id,
        server,
        port=0,
        user=None,
        password=None,
        keepalive=0,
        ssl=None,
    ):

“ssl_params”没有参数 我认为您正在引用 mpython 文档而不是 Micropython 文档