本文属于机器翻译版本。若本译文内容与英语原文存在差异，则一律以英文原文为准。

# 步骤 1：创建 AWS IoT policy
<a name="iot-moisture-policy"></a>

创建 AWS IoT 允许您的树莓派连接并向其发送消息的策略 AWS IoT。

1. 在 [AWS IoT 控制台](https://console.aws.amazon.com/iot)中，如果显示**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）。

1. 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**。

1. 输入 AWS IoT 策略的名称（例如，**MoistureSensorPolicy**）。

1. 在**添加声明**部分中，将现有策略替换为以下 JSON。将{{region}}和{{account}}替换为您的 AWS 区域 和 AWS 账户 号码。  
****  

   ```
   {
       "Version":"2012-10-17",		 	 	 
       "Statement": [
           {
               "Effect": "Allow",
               "Action": "iot:Connect",
               "Resource": "arn:aws:iot:{{us-east-1}}:123456789012:client/RaspberryPi"
           },
           {
               "Effect": "Allow",
               "Action": "iot:Publish",
               "Resource": [
                   "arn:aws:iot:{{us-east-1}}:123456789012:topic/$aws/things/RaspberryPi/shadow/update",
                   "arn:aws:iot:{{us-east-1}}:123456789012:topic/$aws/things/RaspberryPi/shadow/delete",
                   "arn:aws:iot:{{us-east-1}}:123456789012:topic/$aws/things/RaspberryPi/shadow/get"
               ]
           },
           {
               "Effect": "Allow",
               "Action": "iot:Receive",
               "Resource": [
                   "arn:aws:iot:{{us-east-1}}:123456789012:topic/$aws/things/RaspberryPi/shadow/update/accepted",
                   "arn:aws:iot:{{us-east-1}}:123456789012:topic/$aws/things/RaspberryPi/shadow/delete/accepted",
                   "arn:aws:iot:{{us-east-1}}:123456789012:topic/$aws/things/RaspberryPi/shadow/get/accepted",
                   "arn:aws:iot:{{us-east-1}}:123456789012:topic/$aws/things/RaspberryPi/shadow/update/rejected",
                   "arn:aws:iot:{{us-east-1}}:123456789012:topic/$aws/things/RaspberryPi/shadow/delete/rejected"
               ]
           },
           {
               "Effect": "Allow",
               "Action": "iot:Subscribe",
               "Resource": [
                   "arn:aws:iot:{{us-east-1}}:123456789012:topicfilter/$aws/things/RaspberryPi/shadow/update/accepted",
                   "arn:aws:iot:{{us-east-1}}:123456789012:topicfilter/$aws/things/RaspberryPi/shadow/delete/accepted",
                   "arn:aws:iot:{{us-east-1}}:123456789012:topicfilter/$aws/things/RaspberryPi/shadow/get/accepted",
                   "arn:aws:iot:{{us-east-1}}:123456789012:topicfilter/$aws/things/RaspberryPi/shadow/update/rejected",
                   "arn:aws:iot:{{us-east-1}}:123456789012:topicfilter/$aws/things/RaspberryPi/shadow/delete/rejected"
               ]
           },
           {
               "Effect": "Allow",
               "Action": [
                   "iot:GetThingShadow",
                   "iot:UpdateThingShadow",
                   "iot:DeleteThingShadow"
               ],
               "Resource": "arn:aws:iot:{{us-east-1}}:123456789012:thing/RaspberryPi"
           }
       ]
   }
   ```

1. 选择**创建**。