Historical Tag Path in Ignition SDK

3rd Party Modules
1

I’m trying to write a historical query from a component in a module I’m developing. I’m using the standard gateway interface “runTagHistoryQuery” function. It’s all working very well, except I have to set it up with a fully qualified tag path in the client (histprov:historian:/drv:ignition-cody-pc:default:/tag:tags/ramp/ramp0). Obviously I think this is far from intuitive for someone to use so I’d like to whittle my tag path down to one or all of the following:
[ul]

  1. tags/ramp/ramp0
  2. [~]tags/ramp/ramp0
  3. [historian/ignition-cody-pc:default]tags/ramp/ramp0
    [/ul]

Now my question is, how do I take a less than fully qualified tag path from the client and turn it into the a fully qualified historical tag path. I can retrieve the default data source and default tag provider from the client context with:

    ClientContext context = getAppContext();
    defaultDatasource = context.getDefaultDatasourceName();
    defaultTagProvider = context.getDefaultSQLTagsProviderName();

But I’m missing the system name. So I guess my question is
[ul]

  1. What java Class would I use to get the system name?
  2. Am I even approaching this the right way or is there already a class to do this? (I’ve found classes to parse SQL tag paths but not historical).
    [/ul]

Thanks!

2

Ok so with the help of Kyle Chase I’ve retrieved the system name via an RPC call to query the gateway’s internal database.

    PersistenceInterface gwDBInterface = context.getPersistenceInterface();
    PersistentRecord systemRecord = gwDBInterface.find(SystemPropertiesRecord.META, 0);

    return systemRecord.getString(SystemPropertiesRecord.SystemName);

Now I still have to wonder, isn’t there an easier/better way?

3

Hey Cody, did you ever find out if there's a better way? I'm trying to figure out how to handle these properly myself...

4

The proper way to do this nowadays is to use getSystemPropertiesManager() on the GatewayContext, and call that object's getSystemName().

In jython, you can use the netbeans shortcut properties (and should--they are more efficient).

1 Like
5

Thanks!