Edgex的application开发SDK

package main



import (

    "fmt"

    "github.com/edgexfoundry/app-functions-sdk-go/appsdk"

    "github.com/edgexfoundry/app-functions-sdk-go/pkg/transforms"

    "os"

)



func main() {



    // 1) First thing to do is to create an instance of the EdgeX SDK, giving it a service key

    edgexSdk := &appsdk.AppFunctionsSDK{

        ServiceKey: "SimpleFilterXMLApp", // Key used by Registry (Aka Consul)

    }



    // 2) Next, we need to initialize the SDK

    if err := edgexSdk.Initialize(); err != nil {

        edgexSdk.LoggingClient.Error(fmt.Sprintf("SDK initialization failed: %v\n", err))

        os.Exit(-1)

    }



    // 3) Since our FilterByDeviceName Function requires the list of Device Names we would

    // like to search for, we'll go ahead and define that now.

    deviceNames := []string{"Random-Float-Device"}



    // 4) This is our pipeline configuration, the collection of functions to

    // execute every time an event is triggered.

    if err := edgexSdk.SetFunctionsPipeline(

            transforms.NewFilter(deviceNames).FilterByDeviceName, 

            transforms.NewConversion().TransformToXML,

        ); err != nil {

            edgexSdk.LoggingClient.Error(fmt.Sprintf("SDK SetPipeline failed: %v\n", err))

            os.Exit(-1)

        }



    // 5) shows how to access the application's specific configuration settings.

    appSettings := edgexSdk.ApplicationSettings()

    if appSettings != nil {

        appName, ok := appSettings["ApplicationName"]

        if ok {

            edgexSdk.LoggingClient.Info(fmt.Sprintf("%s now running...", appName))

        } else {

            edgexSdk.LoggingClient.Error("ApplicationName application setting not found")

            os.Exit(-1)

        }

    } else {

        edgexSdk.LoggingClient.Error("No application settings found")

        os.Exit(-1)

    }



    // 6) Lastly, we'll go ahead and tell the SDK to "start" and begin listening for events to trigger the pipeline.

    edgexSdk.MakeItRun()

}

func printXMLToConsole(edgexcontext *appcontext.Context, params ...interface{}) (bool,interface{}) {

  if len(params) < 1 { 

    // We didn't receive a result

    return false, errors.New("No Data Received")

  }

  println(params[0].(string))

  return true, nil

}