DeviceShadowEnrich 活动

一个deviceShadowEnrich活动添加了来自Amazon IoT向消息提供Device Shadow 服务。例如，给定以下消息：

{
    "temp": 50,
    "hum": 40,
    "device": { "thingName": "my-thing" }
}

和以下 deviceShadowEnrich 活动：

{
    "deviceShadowEnrich": {
        "name": "MyDeviceShadowEnrichActivity",
        "attribute": "shadow",
        "thingName": "device.thingName",
        "roleArn": "arn:aws:iam::<your-account-number>:role:MyEnrichRole",
        "next": "MyDatastoreActivity"
    }
}

结果是一条类似于以下示例的消息。

{
    "temp": 50,
    "hum": 40,
    "device": {
        "thingName": "my-thing"
    },
    "shadow": {
        "state": {
            "desired": {
                "attributeX": valueX, ...
            },
            "reported": {
                "attributeX": valueX, ...
            },
            "delta": {
                "attributeX": valueX, ...
            }
        },
        "metadata": {
            "desired": {
                "attribute1": {
                    "timestamp": timestamp
                }, ...
            },
            "reported": ": {
                "attribute1": {
                    "timestamp": timestamp
                }, ...
            }
        },
        "timestamp": timestamp,
        "clientToken": "token",
        "version": version
    }
}

您必须在活动定义的 roleArn 字段中指定已附加适当权限的角色。该角色必须具有如下所示的权限策略。

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "iot:GetThingShadow"
            ],
            "Resource": [
                "arn:aws:iot:<region>:<account-id>:thing/<thing-name>"
            ]
        }
    ]
}

和类似如下的信任策略：

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Sid": "",
            "Effect": "Allow",
            "Principal": {
                "Service": "iotanalytics.amazonaws.com"
            },
            "Action": [
                "sts:AssumeRole"
            ]
        }
    ]
}