This plugin intends at converting PIVOT data from/to OPCUA north plugin.

The filter implements the Fledge Filter plugin interface (see filter_plugins).

Filter configuration

See Plugins configuration design for examples and details

The "config" parameter of  "plugin_init" call shall include :

• A "exchanged_data" category with the same content as provided to the OPCUA north plugin. This section is mandatory so that the filter plugin can convert the PIVOT type to OPCUA type.
  

Notes :

• All types not listed in this table are not supported in current version.
• The current implementation provides a default mapping rule for each known type, but some new rules might be added in the future and configured using the "alternate_mapping_rule" option in its parameters.
• While converting from PIVOT to OPCUA, the PIVOT object is "standalone" and the plugin does not need any configuration from this transformation. The "Exchanged Data" section is only used by conversion from OPCUA to PIVOT.

Filter interface

The <Root> key of PIVOT object can be:

In the following table: <type> is equal to

• "SpsTyp", "DpsTyp" (for GTIS)
• "MvTyp" (for GTIM)
• "SpcTyp", "DpcTyp", "IncType" or "ApcTyp" (for GTIC)

The "BscTyp" is not supported currently.

Type of data

The plugin is not responsible for checking that the conversion matches its actual role: typically if the plugin is attached to a North OPCUA service, it will be expected to convert OPCUA to PIVOT, but will anyway convert PIVOT to OPCUA if receiving PIVOT instead of OPCUA as reading. This consistency must be ensured by configuration.

Thus the rules for the conversion is:

• For each object in the reading is modified as follow:
  • If the object name is "PIVOT" and contains the "GTIM" or "GTIS" key, then the reading must be converted from a PIVOT object to an OPCUA "data object".
  • If the object name is "PIVOT" and contains the "GTIC" key, then the reading must be converted from a PIVOT object to an OPCUA "reply object".
  • If the object name is "opcua_operation", then the reading must be converted from an OPCUA control request (operation) to a PIVOT object.
  • Otherwise the reading is not modified.

Converting monitoring data types

For TM/TS, the filter receives PIVOT reading (from south) and creates a corresponding OPC UA reading. The created OPCUA reading has the following JSON equivalent format ("data object"):

{
   "data_object":{
      "do_cot": <int>,
      "do_confirmation": <int>,
      "do_comingfrom": <string>,
      "do_id":  <string>,
      "do_type":  <string>,
      "do_quality": <int>,
      "do_ts_quality": <int>,
      "do_value_quality": <string>,
      "do_source": <string>,
      "do_ts": <int>,
      "do_ts_org": <string>,
      "do_ts_validity": <string>,
      "do_value": <depends on data type...>
   }
}

The content under <Root> will convert the pivot to a opcua object as follow:

Converting commands data types

Converting commands implies two different use case:

• While sending a Fledge "operation" (from North to South). In that case the filter converts an operation with asset_name = "opcua_operation" into a "PIVOTTC" object with an asset_name = "PivotCommand".
• While receiving an acknowledgement for a previous "operation" (from South to North).  In that case, the filter converts a "PIVOT.GTIC" into a "opcua_reply" object.

The conversion rules are details below.

Conversion from opcua_operation to PIVOT.GTIC

Conversion from PIVOT.GTIC to "opcua_reply"