ESP32 - 使用 MicroPython 的 MQTT 到 AWS IoT

Question

我已将 ESP32 注册为 AWS IoT 上的一个事物，并下载了其各自的证书以及公钥和私钥。还通过我的终端中的以下命令验证了这些连接是否正确：

openssl s_client -connect host.iot.region.amazonaws.com:8443 -CAfile AmazonRootCA1.pem -cert certificate.pem.crt -key private.pem.key

这是我的 (main.py) 使用 MicroPython 连接到 AWS IoT 的简单代码

import machine
from network import WLAN
import network
from umqtt.simple import MQTTClient

# AWS endpoint parameters.
HOST = b'HOST'    # ex: b'abcdefg1234567'
REGION = b'REGION'  # ex: b'us-east-1'

CLIENT_ID = "CLIENT_ID"  # Should be unique for each device connected.
AWS_ENDPOINT = b'%s.iot.%s.amazonaws.com' % (HOST, REGION)

keyfile = '/certs/private.pem.key'
with open(keyfile, 'r') as f:
    key = f.read()

certfile = "/certs/certificate.pem.crt"
with open(certfile, 'r') as f:
    cert = f.read()

# SSL certificates.
SSL_PARAMS = {'key': key,'cert': cert, 'server_side': False}


# Setup WiFi connection.
wlan = network.WLAN( network.STA_IF )
wlan.active( True )
wlan.connect( "SSID", "PASSWORD" )

while not wlan.isconnected():
  machine.idle()

# Connect to MQTT broker.
mqtt = MQTTClient( CLIENT_ID, AWS_ENDPOINT, port = 8883, keepalive = 10000, ssl = True, ssl_params = SSL_PARAMS )
mqtt.connect()
# Publish a test MQTT message.
mqtt.publish( topic = 'test', msg = 'hello world', qos = 0 )

但当我尝试连接时出现此错误：

(-17168, 'MBEDTLS_ERR_RSA_PRIVATE_FAILED+MBEDTLS_ERR_MPI_ALLOC_FAILED')

Answer 1

经过一番努力，我让它发挥作用。我必须使用 idf3 MicroPython 二进制文件，

esp32-idf3-20191220-v1.12.bin

idf4 二进制文件和 v1.12 之后的 idf3 不起作用。存在堆不够和内存分配问题。

- - - - - - 编辑 - - - - - -

新闻更新！基于 idf4 的新 v1.15 版 MicroPython 可与 AWS MQTT for IoT 配合使用。