Skip to content

App Service Configurable - Target Type

The default TargetType for data flowing into the functions pipeline is an EdgeX Event DTO. There are cases when this incoming data might not be an EdgeX Event DTO. There are two values that TargetType can be configured to for non-Event data.

Raw TargetType

In these cases the Pipeline can be configured using TargetType="raw" to set the TargetType to be a byte array/slice, i.e. []byte. The first function in the pipeline must then be one that can handle the []byte data. The compression, encryption and export functions are examples of pipeline functions that will take input data that is []byte.

Example - Configure the functions pipeline to compress, encrypt and then export the []byte data via HTTP 

Writable:
  Pipeline:
    TargetType: "raw"
    ExecutionOrder: "Compress, Encrypt, HTTPExport"
    Functions:
      Compress:
        Parameters:
          Algorithm: "gzip"
      Encrypt:
        Parameters:
          Algorithm: "aes256" 
          SecretName: "aes"
          SecretValueKey: "key"
      HTTPExport:
        Parameters:
          Method: "post"
          Url: "http://my.api.net/edgexdata"
          MimeType: "application/text"

If along with this pipeline configuration, you also configured the Trigger to be http trigger, you could then send any data to the app-service-configurable's /api/v3/trigger endpoint and have it compressed, encrypted and sent to your configured URL above.

Example - HTTP Trigger configuration

Trigger:
  Type: "http"

Metric TargetType

This setting when set to true will cause the TargetType to be &dtos.Metric{} and is meant to be used in conjunction with the new ToLineProtocol function. See ToLineProtocol section below for more details. In addition, the Trigger SubscribeTopicsmust be set to "edgex/telemetry/#" so that the function receives the metric data from the other services.

Example - Metric TargetType 

Writable:
  Pipeline:
    TargetType: "metric"
    ExecutionOrder: "ToLineProtocol, ..."
  ...
    Functions:
      ToLineProtocol:
        Parameters:
          Tags: "" # optional comma separated list of additional tags to add to the metric in to form "tag:value,..."
  ...
 Trigger:
   SubscribeTopics: telemetry/#"