OMFLinkedData Class Reference

The OMFLinkedData class. More...

#include <omflinkeddata.h>

Public Member Functions
	OMFLinkedData (std::unordered_map< std::string, LALookup > *linkedAssetState, const OMF_ENDPOINT PIServerEndpoint=ENDPOINT_CR)
bool	processReading (OMFBuffer &payload, bool needDelim, const Reading &reading, const std::string &DefaultAFLocation=std::string(), OMFHints *hints=NULL)
	OMFLinkedData constructor, generates the OMF message containing the data. More...
void	buildLookup (const std::vector< Reading *> &reading)
	If the entries are needed in the lookup table for this block of readings then create them. More...
void	setSendFullStructure (const bool sendFullStructure)
bool	flushContainers (HttpSender &sender, const std::string &path, std::vector< std::pair< std::string, std::string > > &header, OMFError &error, bool *isConnected)
	Flush the container definitions that have been built up. More...
void	setDelimiter (const std::string &delimiter)
void	setFormats (const std::string &doubleFormat, const std::string &integerFormat)

Detailed Description

The OMFLinkedData class.

A reading is formatted with OMF specifications using the linked type creation scheme supported for OMF Version 1.2 onwards.

This is based on the new mechanism discussed at AVEVA World 2022 and the mechanism is detailed in the Google Doc, https://docs.google.com/document/d/1w0e7VRqX7xzc0lEBLq-sYhgaHE0ABasOa6EC9dJMrMs/edit

The principle is to use links to containers in OMF with each container being a single data point in the asset. There are no specific types for the assets, they share a set of base types via these links. This should allow for readings that have different sets of datapoints for each asset.

It is also a goal of this mechanism to move away from the need to persist state data between invocations and make the process more robust.

Member Function Documentation

buildLookup()

void OMFLinkedData::buildLookup

(

const std::vector< Reading *> &

reading

)

If the entries are needed in the lookup table for this block of readings then create them.

Parameters

readings

A block of readings to process

This loop creates the data values for each of the datapoints in the reading.

flushContainers()

bool OMFLinkedData::flushContainers	(	HttpSender &	sender,
		const std::string &	path,
		std::vector< std::pair< std::string, std::string > > &	header,
		OMFError &	error,
		bool *	isConnected
	)

Flush the container definitions that have been built up.

Parameters

sender	HTTP client
path	REST server URL
header	REST call headers
error	OMFError object with parsed PI Web API HTTP response
isConnected	Set to false if REST call shows loss of connection to PI

Returns

true if the containers were successfully flushed

processReading()

bool OMFLinkedData::processReading	(	OMFBuffer &	payload,
		bool	needDelim,
		const Reading &	reading,
		const std::string &	DefaultAFLocation = std::string(),
		OMFHints *	hints = NULL
	)

OMFLinkedData constructor, generates the OMF message containing the data.

Parameters

payload	The buffer into which to populate the payload
delim	Add a delimiter before outputting anything
reading	Reading for which the OMF message must be generated
AFHierarchyPrefix	Unused at the current stage
hints	OMF hints for the specific reading for changing the behaviour of the operation

This loop creates the data values for each of the datapoints in the reading.

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The documentation for this class was generated from the following files:

• C/plugins/north/OMF/include/omflinkeddata.h
• C/plugins/north/OMF/linkdata.cpp