reading/Writing OPC tags from a python script outside Ignition

Ignition
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Hi All,
I’m trying to build an application outside the Ignition platform which will parse some data and I need to read some OPC tags that is on Ignition from the .py script. I explored the OpenOPC module on python but I’m not able to find my OPC server that is configured on the Ignition gateway through that module. Has anyone taken this kind of a route before? Basically, I need to access the OPC tags on Ignition from a separate python script outisde of Ignition. Thanks in advance.

2

Ignition has no API for external access to tags. There are two supported ways and one unsupported way:

  1. Set Ignition to Expose Tags via OPC (an all-or-nothing setting) and then use and OPC client to access the tags,

  2. Install Ignition’s WebDev module and use its features to implement your own http(s) API. The jython scripting within such an API can expose pretty much anything inside Ignition to external clients, or

  3. Write your own 3rd-party module that registers a java servlet and implement your own http(s) API in java, much like (2). You are pretty much on your own with this one.

1 Like
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Thanks a lot, Phil. I will try out the first two options.