ctrlX Data Layer and OSI PI Integration

[[inputs.ctrlx_datalayer]]
   ## Hostname or IP address of the ctrlX CORE Data Layer server
   ##  example: server = "localhost"        # Telegraf is running directly on the device
   ##           server = "192.168.1.1"      # Connect to ctrlX CORE remote via IP
   ##           server = "host.example.com" # Connect to ctrlX CORE remote via hostname
   ##           server = "10.0.2.2:8443"    # Connect to ctrlX CORE Virtual from development environment
   server = "localhost"

   ## Authentication credentials
   username = "boschrexroth"
   password = "boschrexroth"

   ## Use TLS but skip chain & host verification
   # insecure_skip_verify = false

   ## Timeout for HTTP requests. (default: "10s")
   # timeout = "10s"


   ## Create a ctrlX Data Layer subscription.
   ## It is possible to define multiple subscriptions per host. Each subscription can have its own
   ## sampling properties and a list of nodes to subscribe to.
   ## All subscriptions share the same credentials.
   [[inputs.ctrlx_datalayer.subscription]]
      ## The name of the measurement. (default: "ctrlx")
      measurement = "memory"

      ## Configure the ctrlX Data Layer nodes which should be subscribed.
      ## address - node address in ctrlX Data Layer (mandatory)
      ## name    - field name to use in the output (optional, default: base name of address)
      ## tags    - extra node tags to be added to the output metric (optional)
      ## Note: 
      ## Use either the inline notation or the bracketed notation, not both.
      ## The tags property is only supported in bracketed notation due to toml parser restrictions
      ## Examples:
      ## Inline notation 
      nodes=[
         {name="available", address="framework/metrics/system/memavailable-mb"},
         {name="used", address="framework/metrics/system/memused-mb"},
      ]
      ## Bracketed notation
      # [[inputs.ctrlx_datalayer.subscription.nodes]]
      #    name   ="available"
      #    address="framework/metrics/system/memavailable-mb"
      #    ## Define extra tags related to node to be added to the output metric (optional)
      #    [inputs.ctrlx_datalayer.subscription.nodes.tags]
      #       node_tag1="node_tag1"
      #       node_tag2="node_tag2"
      # [[inputs.ctrlx_datalayer.subscription.nodes]]
      #    name   ="used"
      #    address="framework/metrics/system/memused-mb"

      ## The switch "output_json_string" enables output of the measurement as json. 
      ## That way it can be used in in a subsequent processor plugin, e.g. "Starlark Processor Plugin".
      # output_json_string = false

      ## Define extra tags related to subscription to be added to the output metric (optional)
      # [inputs.ctrlx_datalayer.subscription.tags]
      #    subscription_tag1 = "subscription_tag1"
      #    subscription_tag2 = "subscription_tag2"

      ## The interval in which messages shall be sent by the ctrlX Data Layer to this plugin. (default: 1s)
      ## Higher values reduce load on network by queuing samples on server side and sending as a single TCP packet.
      # publish_interval = "1s"

      ## The interval a "keepalive" message is sent if no change of data occurs. (default: 60s)
      ## Only used internally to detect broken network connections.
      # keep_alive_interval = "60s"

      ## The interval an "error" message is sent if an error was received from a node. (default: 10s)
      ## Higher values reduce load on output target and network in case of errors by limiting frequency of error messages.
      # error_interval = "10s"

      ## The interval that defines the fastest rate at which the node values should be sampled and values captured. (default: 1s)
      ## The sampling frequency should be adjusted to the dynamics of the signal to be sampled.
      ## Higher sampling frequencies increases load on ctrlX Data Layer.
      ## The sampling frequency can be higher, than the publish interval. Captured samples are put in a queue and sent in publish interval.
      ## Note: The minimum sampling interval can be overruled by a global setting in the ctrlX Data Layer configuration ('datalayer/subscriptions/settings').
      # sampling_interval = "1s"

      ## The requested size of the node value queue. (default: 10)
      ## Relevant if more values are captured than can be sent.
      # queue_size = 10

      ## The behaviour of the queue if it is full. (default: "DiscardOldest")
      ## Possible values: 
      ## - "DiscardOldest"
      ##   The oldest value gets deleted from the queue when it is full.
      ## - "DiscardNewest"
      ##   The newest value gets deleted from the queue when it is full.
      # queue_behaviour = "DiscardOldest"

      ## The filter when a new value will be sampled. (default: 0.0)
      ## Calculation rule: If (abs(lastCapturedValue - newValue) > dead_band_value) capture(newValue).
      # dead_band_value = 0.0

      ## The conditions on which a sample should be captured and thus will be sent as a message. (default: "StatusValue")
      ## Possible values:
      ## - "Status"
      ##   Capture the value only, when the state of the node changes from or to error state. Value changes are ignored.
      ## - "StatusValue" 
      ##   Capture when the value changes or the node changes from or to error state.
      ##   See also 'dead_band_value' for what is considered as a value change.
      ## - "StatusValueTimestamp": 
      ##   Capture even if the value is the same, but the timestamp of the value is newer.
      ##   Note: This might lead to high load on the network because every sample will be sent as a message
      ##   even if the value of the node did not change.
      # value_change = "StatusValue"

[[outputs.http]]
  ## PI Web API endpoint for writing a single value to a PI Point by Web ID
  url = "https://${PI_HOST}/piwebapi/streams/${WEB_ID}/value"

  ## Use POST for each batch
  method       = "POST"
  content_type = "application/json"

  ## Basic-auth header (base64-encoded "DOMAIN\\user:password")
  headers = { Authorization = "Basic ${BASIC_AUTH}" }

  ## Serialize Telegraf metrics as JSON
  data_format           = "json"
  json_timestamp_units  = "1ms"

  ## Render the JSON body that PI Web API expects
  body_template = """
  {{ range .Metrics -}}
  { "Timestamp": "{{ .timestamp | formatDate \"2006-01-02T15:04:05Z07:00\" }}", "Value": {{ index .fields 0 }} }
  {{ end -}}
  """

  ## Tune networking / batching if needed
  # timeout     = "10s"
  # batch_size  = 1