我正在尝试开发一种azure函数,该函数从一个内置的eventhub接收消息并对其进行处理,并将结果发送到Azure IoT中心中配置的另一个IoT设备。下面是代码:
module.exports =函数(上下文,IoTHubMessages){
var Mqtt = require('azure-iot-device-mqtt').Mqtt;
var DeviceClient = require('azure-iot-device').Client
var Message = require('azure-iot-device').Message
var connectionString = '{connectionstring of the target device}';
var acRoom1 = DeviceClient.fromConnectionString(connectionString, Mqtt);
var totalPerson = 0;
var events = IoTHubMessages.length;
context.log(JSON.stringify(IoTHubMessages));
context.log(Array.isArray(IoTHubMessages));
context.log(`Number of entries: ${IoTHubMessages.length}`);
IoTHubMessages.forEach(message => {
context.log(`Processed message: ${JSON.stringify(message)}`);
totalPerson = totalPerson + message.personCount;
context.log(`Total count: ${totalPerson}`);
});
var avgPersonCount = Math.round( totalPerson / events );
context.log(`Average person count: ${avgPersonCount}`);
var temp = 24;
if ( avgPersonCount > 5){
temp = 20;
}
else if ((avgPersonCount>2) && (avgPersonCount <= 5)){
temp = 22;
}
else {
temp = 24;
}
var msg = new Message(`Setting temperature to ${temp} C`);
context.log('Sending message: ' + msg.getData());
context.log(`Temeperature set to ${temp} C`);
acRoom1.sendEvent(msg);
context.done();
};
我遇到的问题是,我发送给设备的事件又回到了这种天蓝色的功能。我相信,我需要在“消息路由”中做一些事情,但是不确定需要做什么。
整个解决方案(我想要实现)的流程如下
相机-> Azure IOT集线器-> Azure功能-> AC
您可以通过设备ID过滤事件,但是更具扩展性的方法是添加appProperty。如果要将所有AC事件发送到其他端点,则可以在AC发送的消息中添加一个appProperty。示例:
var msg = new Message(`Setting temperature to ${temp} C`);
msg .properties.add('eventType', 'AC');
context.log('Sending message: ' + msg.getData());
context.log(`Temeperature set to ${temp} C`);
acRoom1.sendEvent(msg);
之后,您可以转到IoT中心并添加新路线。您可以将这些事件路由到另一个端点,如下所示:
由于您的相机未发送此appProperty,它将依赖于后备路由,并且您的Azure函数仍将处理这些事件。另一个也许更可靠的选择是仅将摄像机消息发送到特定路由。但是任何一个都行!