步骤 1：创建 AWS IoT 策略

创建允许你的 Raspberry Pi 连接和向其发送消息的 AWS IoT 策略 AWS IoT。

1. 在 AWS IoT 控制台中，如果显示 Get started (开始使用) 按钮，请选择该按钮。否则，请在导航窗格中展开 Secure（安全），然后选择 Policies（策略）。

2. 如果显示您还没有任何策略对话框，请选择创建策略。否则，选择 创建。

3. 输入 AWS IoT 策略的名称（例如MoistureSensorPolicy）。

4. 在添加声明部分中，将现有策略替换为以下 JSON。account用你region的 and AWS 账户 编号替换 AWS 区域 和。

   JSON

   {
       "Version": "2012-10-17",
       "Statement": [
           {
               "Effect": "Allow",
               "Action": "iot:Connect",
               "Resource": "arn:aws:iot:us-east-1:111122223333:client/RaspberryPi"
           },
           {
               "Effect": "Allow",
               "Action": "iot:Publish",
               "Resource": [
                   "arn:aws:iot:us-east-1:111122223333:topic/$aws/things/RaspberryPi/shadow/update",
                   "arn:aws:iot:us-east-1:111122223333:topic/$aws/things/RaspberryPi/shadow/delete",
                   "arn:aws:iot:us-east-1:111122223333:topic/$aws/things/RaspberryPi/shadow/get"
               ]
           },
           {
               "Effect": "Allow",
               "Action": "iot:Receive",
               "Resource": [
                   "arn:aws:iot:us-east-1:111122223333:topic/$aws/things/RaspberryPi/shadow/update/accepted",
                   "arn:aws:iot:us-east-1:111122223333:topic/$aws/things/RaspberryPi/shadow/delete/accepted",
                   "arn:aws:iot:us-east-1:111122223333:topic/$aws/things/RaspberryPi/shadow/get/accepted",
                   "arn:aws:iot:us-east-1:111122223333:topic/$aws/things/RaspberryPi/shadow/update/rejected",
                   "arn:aws:iot:us-east-1:111122223333:topic/$aws/things/RaspberryPi/shadow/delete/rejected"
               ]
           },
           {
               "Effect": "Allow",
               "Action": "iot:Subscribe",
               "Resource": [
                   "arn:aws:iot:us-east-1:111122223333:topicfilter/$aws/things/RaspberryPi/shadow/update/accepted",
                   "arn:aws:iot:us-east-1:111122223333:topicfilter/$aws/things/RaspberryPi/shadow/delete/accepted",
                   "arn:aws:iot:us-east-1:111122223333:topicfilter/$aws/things/RaspberryPi/shadow/get/accepted",
                   "arn:aws:iot:us-east-1:111122223333:topicfilter/$aws/things/RaspberryPi/shadow/update/rejected",
                   "arn:aws:iot:us-east-1:111122223333:topicfilter/$aws/things/RaspberryPi/shadow/delete/rejected"
               ]
           },
           {
               "Effect": "Allow",
               "Action": [
                   "iot:GetThingShadow",
                   "iot:UpdateThingShadow",
                   "iot:DeleteThingShadow"
               ],
               "Resource": "arn:aws:iot:us-east-1:111122223333:thing/RaspberryPi"
           }
       ]
   }
   

5. 选择创建。