In ourlast postwe covered how Core Services in the newedgexproject from the Linux Foundation帮助工程师快速构建边缘计算和IIT应用程序。核心服务是Microservices Edgex提供的，将物理电信号从工业设备转换为数字信息。
在这篇文章中，我们将重点介绍Edgex如何从工业资产中提供数字数据，可用于高级计算系统，例如预测分析和机器学习。
But before the data is made available to those systems, EdgeX uses what it calls Supporting Microservices to do some pretty high-tech stuff to package the data and make it easily accessible.
支持微服务包括使Edgex运行的广泛流程和任务，同时还为Edge Computing应用程序提供了分析和智能。
Normal software application duties such as logging, scheduling, service registration, and data cleanup (scrubbing) are facilitated by microservices at this layer. Additionally, the Rules Engine and Alerts/Notifications microservices are logically grouped within this layer of EdgeX and operate on top of the EdgeX Core Services.
edgex警报和通知
有时，需要通知人类或其他系统。来自运行EdgeX的节点或节点上的其他微服务的工业资产的数据可能指出问题或机会。
When that happens, the警报和通知microservice provides the means to deliver that information.
以下是其他服务可能需要发送的警报和通知的几个示例：
- Sensor data outside of certain parameters (usually detected by the Rules Engine service)
- System or service malfunctions (usually detected by system management services)
Alerts and notifications are essentially the same thing in EdgeX. Both are system messages indicating something has happened and may need attention on the part of some administrator or operator. But alerts imply a type of notification message that is more critical—possibly requiring immediate action.
您可以将EdgeX上的警报和通知与传统的HMI进行比较。
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上图显示了高级别在Edgex上运行和功能的警报和通知如何。为微服务，本地应用程序和远程应用程序提供了API。这些API可以在REST，AMQP，MQTT或任何标准应用程序协议中处于休息中。
在当前版本的警报和通知中，仅提供了恢复的界面（再次有RESTFULE API内容）。
通知接收器可以是云或服务器室或本地数据中心中的用户或应用程序系统。
When a user or application subscribes to the Alerts & Notifications microservice, the subscriber then receives notifications via defined receiving channels when events occur.
这receiving channels include SMS message, email, REST callback, AMQP, MQTT, and so on. In the first version of Alerts & Notifications, only email and REST callback channels are provided.
Edgex记录
网络边缘的登录也对包括EdgeX在内的所有现代软件应用程序都起着重要作用。
这edgex记录microservice utilizes LOGBack, an open-source Java-based logging utility, as its underlying logging framework. It can log data to either a local file or to a MongoDB database. And the EdgeX Logging service provides a RESTful API for other microservices to request log entries.
Edgex规则引擎
这规则引擎microservice monitors incoming sensor and device data to make sure readings are within target ranges, and it triggers immediate device actuation. The engine provides "intelligence" at or near the edge for faster response times.
Drools is an open-source rules engine provided by the JBoss community.
预计，由于Edgex项目的开发和采用更广泛，因此第三方提供的许多其他边缘分析能力将更换或增强该微服务。
这规则引擎microservice comes with a RESTful API that allows new rules to be added and removed.New rules, defined in JSON, can be dynamically added to the Rules Engine (via REST POST). The JSON data provided is translated into Drools Rules files (.drl files) under the covers by the microservice.
So that’s a bit more info about how EdgeX operates behind the scenes to help build and deliver edge computing applications.
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