EDGEX FOUNDRY配置参数 --- Export-Distro

export-distro是EDGEX系统中数据转发服务，export-distro使用介绍如下，他有2个启动参数可以配置：

registry是一个bool量，True表示export-distro的配置参数是从consul拉取，False表示从本地配置文件载入。
profile本地配置文件的路径，即便registry=True，该参数也必须要指明一个配置文件，因为连接consul服务所需的host，port等参数必须从本地的配置文件中获取。

Usage: %s [options]
Server Options:
    -r, --registry                  Indicates service should use Registry
    -p, --profile <name>            Indicate configuration profile other than default
Common Options:
    -h, --help                      Show this message

export-distro的配置文件

[Writable]
MarkPushed = false
LogLevel = 'INFO'

[Service]
BootTimeout = 30000
ClientMonitor = 15000
CheckInterval = '10s'
Host = 'localhost'
Port = 48070
Protocol = 'http'
ReadMaxLimit = 100
StartupMsg = 'This is the Export Distro Microservice'
Timeout = 5000

[Registry]
Host = 'localhost'
Port = 8500
Type = 'consul'

[Logging]
EnableRemote = false
File = './logs/edgex-export-distro.log'

[Clients]
  [Clients.Export]
  Protocol = 'http'
  Host = 'localhost'
  Port = 48071

  [Clients.Logging]
  Protocol = 'http'
  Host = 'localhost'
  Port = 48061

  [Clients.CoreData]
  Protocol = 'http'
  Host = 'localhost'
  Port = 48080

[Certificates]
  [Certificates.MQTTS]
  Cert = 'dummy.crt'
  Key = 'dummy.key'

  [Certificates.AWS]
  Cert = 'dummy.crt'
  Key = 'dummy.key'

[MessageQueue]
Protocol = 'tcp'
Host = 'localhost'
Port = 5563
Type = 'zero'
Topic = 'events'

[AnalyticsQueue]
Protocol = 'tcp'
Host = '*'
Port = 5566
Type = 'zero'

如上是项目自带的export-distro的配置文件 ,主要分8部分，export-distro启动后会将配置文件的信息导入如下结构中，若registry=True则根据Registry中的信息连接consul并拉取相应的配置信息覆盖之前从本地配置文件中读取到的信息。

type ConfigurationStruct struct {
	Writable       WritableInfo
	Certificates   map[string]CertificateInfo
	Clients        map[string]config.ClientInfo
	Logging        config.LoggingInfo
	MessageQueue   config.MessageQueueInfo
	AnalyticsQueue config.MessageQueueInfo
	Registry       config.RegistryInfo
	Service        config.ServiceInfo
}

Writable

type WritableInfo struct {
	MarkPushed     bool
	LogLevel       string
}

MarkPushed     是否提供数据成功转发后的通知，如果使能，那么AnalysticsQueue必须设置
LogLevel       日志等级

Clients

// ClientInfo provides the host and port of another service in the eco-system.
type ClientInfo struct {
	// Host is the hostname or IP address of a service.
	Host string
	// Port defines the port on which to access a given service
	Port int
	// Protocol indicates the protocol to use when accessing a given service
	Protocol string
}

Host 微服务的地址
Port 微服务的端口
Protocol 微服务所使用的协议，目前仅支持http

export-client运行时需要使用其他微服务提供的功能，Client便是连接其他微服务所必须的参数，这是一个map参数，key值便是其他微服务的名字，value便是client的具体参数信息, export-client正常运行一般需要使用logging, core-data和export-client三个微服务。

Logging

// LoggingInfo provides basic parameters related to where logs should be written.
type LoggingInfo struct {
	EnableRemote bool
	File         string
}

   EnableRemote True: log于support-logging微服务持久化（support-logging的连接参数由Clients字段提供）， False：log于本地文件持久化
   File         log本地持久化时日志文件的路径

Registry

// RegistryInfo defines the type and location (via host/port) of the desired service registry (e.g. Consul, Eureka)
type RegistryInfo struct {
	Host string
	Port int
	Type string
}

consul连接参数

MessageQueue

// MessageQueueInfo provides parameters related to connecting to a message queue
type MessageQueueInfo struct {
	// Host is the hostname or IP address of the broker, if applicable.
	Host string
	// Port defines the port on which to access the message queue.
	Port int
	// Protocol indicates the protocol to use when accessing the message queue.
	Protocol string
	// Indicates the message queue platform being used.
	Type string
	// Indicates the topic the data is published/subscribed
	Topic string
}

export-distro是消息队列的消费者，生产者是core-data. 因此该字段的内容与core-data中相应字段含义相同。

AnalyticsQueue

// MessageQueueInfo provides parameters related to connecting to a message queue
type MessageQueueInfo struct {
	// Host is the hostname or IP address of the broker, if applicable.
	Host string
	// Port defines the port on which to access the message queue.
	Port int
	// Protocol indicates the protocol to use when accessing the message queue.
	Protocol string
	// Indicates the message queue platform being used.
	Type string
	// Indicates the topic the data is published/subscribed
	Topic string
}

处理后的消息成功转发后的通知消息发布，此处为生产者，字段含义同上

Certificates

type CertificateInfo struct {
	Cert string
	Key  string
}

一般接收EdgeX转发数据的外部系统是IOT平台如AWS的IOT平台，这些平台接受数据的时候需要提供对应的秘钥文件，该字段就是这些文件，当然外部系统也可以是其他接口兼容的服务。