edgex-foundry框架下的应用开发
edgex-foundry架构时一中微服务架构，通过docker封装程很多小的微服务，各个微服务之间是通过restful api的形式进行通讯，
在edgex-foundry下的开发主要在device server、support server、export server上开发。
开发时应该做一下几点：
一、在edgex架构中定义自己的信息
1.edgex :采集设备数据之前需要了解到的设备的相关信息，向设备发送的相关命令
2.Addressables :通过rest api设置一些设备的物理地址，device server的ip地址 ，端口号等信息
POST to http://localhost:48081/api/v1/addressable
BODY: {"name":"camera1 address","protocol":"HTTP","address":"172.17.0.1","port":49999,"path":"/camera1","publisher":"none","user":"none","password":"none","topic":"none"}
3.value description:主要时对某一个值的描述
POST to http://localhost:48080/api/v1/valuedescriptor//注意value description存储到core data数据库中,对数据提供了上下文和单位
BODY: {"name":"humancount",//unique
"description":"people count", "min":"0","max":"100","type":"I","uomLabel":"count","defaultValue":"0","formatting":"%s","labels":["count","humans"]}
二、定义你的设备
Adding a Device Profile
POST to http://localhost:48081/api/v1/deviceprofile/uploadfile
FORM-DATA:
key: “file”
value: EdgeX_CameraMonitorProfile.yml
device profile中的内容格式：
name: "camera monitor profile"
manufacturer: "Dell"
model: "Cam12345"
labels:
- "camera"
description: "Human and canine camera monitor profile"
commands:
-
name: People
get:
path: "/api/v1/devices/{deviceId}/peoplecount"//addressable中的url拼出路径进行访问
responses:
-
code: "200"
description: "Number of people on camera"
expectedValues: ["humancount"] //返回的json中的key值。
-
code: "503"
description: "service unavailable"
expectedValues: ["cameraerror"]
device profile中定义了如何和设备和传感器进行通讯。定义了一些命令去控制设备。
三、注册你的device service
向meta data中发送post请求
POST to http://localhost:48081/api/v1/deviceservice
BODY: {
"name":"camera control device service", //unique
"description":"Manage human and dog counting cameras",
"labels":["camera","counter"],
"adminState":"unlocked",//locked代表不响应任何command请求和发送device data
"operatingState":"enabled", //不能被其他的服务设置，是该服务操作状态的一个标志
"addressable":{"name":"camera control"}
}
四、创建设备
提供设备必需在meta data server中将device profile、deivce service、addressable联系起来。
通过apI的形式：
POST to http://localhost:48081/api/v1/device
BODY: {"name":"countcamera1",
"description":"human and dog counting camera #1",
"adminState":"unlocked",
"operatingState":"enabled",
"addressable":{"name":"camera1 address"},//addressable中的name
"labels":["camera","counter"],
"location":"",
"service":{"name":"camera control device service"},//device service中的name
"profile":{"name":"camera monitor profile"}}//device profile中的name
GET to http://localhost:48081/api/v1/deviceservice得到所有的deviceservice的信息
GET to http://localhost:48081/api/v1/deviceservice/label/camera得到label为camera的device service的信息
五、调用命令
列出设备的命令：
GET to http://localhost:48082/api/v1/device/name/countcamera1列出名字为countcamera1的设备的信息
{
"id": "5c6bcc319f8fc20001995995",
"name": "JC.RR5.NAE9.ConfRoom.Padre.Island01",
"adminState": "UNLOCKED",
"operatingState": "ENABLED",
"lastConnected": 1550713108339,
"lastReported": 0,
"labels": [
"thermostat",
"industrial"
],
"location": null,
"commands": [
{
"created": 1550568497699,
"modified": 0,
"origin": 0,
"id": "5c6bcc319f8fc2000199598d",
"name": "CurrentTemperature",
"get": {
"path": "/api/v1/device/{deviceId}/CurrentTemperature",
"responses": [
{
"code": "200",
"description": null,
"expectedValues": [
"AnalogInput_3000290"
]
},
{
"code": "503",
"description": "service unavailable",
"expectedValues": []
}
],
"url": "http://edgex-core-command:48082/api/v1/device/5c6bcc319f8fc20001995995/command/5c6bcc319f8fc2000199598d"
//调用device command的接口/deivce/id/command/id
},
},
]
}
查看一个值的描述：
GET to http://localhost:48080/api/v1/valuedescriptor//注意 这个值存储在core data中
调用command
首先查看设备的命令列表得到相关的url:然后就可以调用
PUT to http://localhost:48082/api/v1/device/
BODY: {"depth":"9"}
六 、发送事件和读取数据
设备主动发送事件数据：
首先数据会以event的形式上报。通过对一个值的value decription（通过api设定）来读取events。多个值通过key/value对组合成一个event进行发送。
POST to http://localhost:48080/api/v1/event
BODY: {"device":"countcamera1","readings":[{"name":"humancount","value":"5"},{"name":"caninecount","value":"3"}]}
也可以在每个value中添加一个时间戳如下
BODY: {"device":"countcamera1","origin":1471806386919, "readings":[{"name":"humancount","value":"1","origin":1471806386919},{"name":"caninecount","value":"0","origin":1471806386919}]}
采集存到数据库中的设备的数据：
得到event的数量
GET to http://localhost:48080/api/v1/event/count
获得countcameral设备的10条信息
GET to http://localhost:48080/api/v1/event/device/countcamera1/10
获得countcameral设备中关于humancount的10条数据
GET to http://localhost:48080/api/v1/reading/name/humancount/10
七、export 你设备的数据到云
rule engine会自动的注册为export server，或将所有的过滤后的数据都export到云端
如果想注册一个新的设备来接受core data中的数据则要注册export service
首先要清楚注册的export service是以什么形式向数据发出去让云端的service接收，http or mqtt
下面注册个matt的export service
POST to http://localhost:48071/api/v1/registration
BODY: {"name":"MyMQTTTopic",
"addressable:{"name":"MyMQTTBroker","protocol":"TCP","address":"tcp://m10.cloudmqtt.com","port":15421,"publisher":"EdgeXExportPublisher","user":"hukfgtoh","password":"mypass","topic":"EdgeXDataTopic"},
"format":"JSON",
"encryption":{"encryptionAlgorithm":"AES","encryptionKey":"123","initializingVector":"123"},
"enable":true,
"destination":"MQTT_TOPIC"}
具体的api文档查看
https://docs.edgexfoundry.org/index.html