OpChange

(VTScada-Layer function. Must be called with a leading backslash.)

Description:	Wrapper for TagMigrator\OpChange. Performs an immediate deploy of a single tag change without disturbing any other tag changes already in place on the local branch. The tags must already exist.
Returns:	Object value of the worker module.
Usage:	Script Only.
Function Groups:	Configuration
Related to:	SimpleOpChange \| GetTagConfiguredParameters \| ModifyTags
Format:	\OpChange(TagName, ParmsDict, User[, Comment, Merge])
Parameters:

Tagname

Required. The name of the tag to be changed.

ParmsDict

Required. A dictionary of tag parameters to change.
The keys are parameter names and the values are the parameter values. For example:

{
  "Address": 40001,
  "Questionable": 0
}

User

Required. The user responsible for the operational change.

Comment

Optional text. A descriptive comment about the change.

Merge

Optional Boolean. Defaults to TRUE. Controls whether the parameters are to be merged with the existing tag's parameters. If false, the parameters replace the tag's parameters and are expected to contain user and timestamp metadata.

Comments:

If your application is set to auto-deploy, then OpChange and ModifyTags accomplish the same result.
If auto-deploy is not set, then there is a difference in the result of the two functions. ModifyTags makes a tag change locally, whereas OpChange will immediately deploy that tag change. Running a deploy operation after ModifyTags' change, results in the entire tag file (and all the included tags and their parameters) being deployed. OpChange is able to deploy just the one change to the one tag within the file, leaving other modified tags in that file as local changes.

OpChanges are used for any tag change that is expected to be performed during systems operation, as opposed to changes made during configuration. The example is an operator changing a tag's questionable status by using the context menu rather than opening the configuration dialog.

When called with the Merge==FALSE parameter it is possible to revert a tag parameter to its default or remove an override using the API GetTagConfiguredParameters. If OPChange is called with Merge=FALSE without using this API, there is no way to remove some configured parameters while keeping others. To make changes to some configured parameters, called GetTagConfiguredParameters, modify the dictionary of parameters (add/modify/remove), then pass the modified dictionary into a call to OPChange.