Documentation of code

Hello all,
I was wondering if anyone had found any good methods of documenting their Vision applications in Ignition. I’m looking to document tags, windows, templates and scripting.

Right now i am updating a word document, thinking about using doxygen for the scripting.

Is there a better way? Maybe is it even possible to get scripting behind the preview windows which are given in the Designer Mode for the differerent windows so that these could be used in the documentation?

Thanks in advance!

You can drive yourself crazy documenting things with Ignition as it's not a pure code environment like you would have if you programmed everything from scratch.

I think the most straightforward way is to document how certain processes work. How do you add a recipe? Load a recipe? What tags handle that, and what values on those tags mean what semantically(1=Run, 2=Stop, 4=Fault, or whatever it is)?

Anything that your gateway shells out to some other software - definitely document that because even if you don't document everything within Ignition most advanced users can figure out what the intent was, but when you shell out to 3rd party software that may not be well known or have co-workers are less familiar with it, this most definitely needs to be documented.

In terms of documenting windows, I try to just make every window follow a similar setup, and then I document those conventions. Any popup that allows INSERT/UPDATE of a database table should look relatively similar, have some initial data payload that populates the window, and the relatively similar code pattern to run your db actions. Obviously exceptions exist but most CRUD operations end up looking similar (CRUD meaning Create Read Update Delete actions on a database).

For documenting scripts I follow the google style

def myImportantFunction(arg1, arg2, keyword1=False):
    """
    This function does important stuff!
    Args:
        arg1: int, if 1, then we do x, if 2 we do y, else we throw an error
        arg2: str, the message that populates the header/banner of a GUI while this runs
        keyword1: bool, if False, modifies function behavior by doing A, if true modifies funciton behavior by doing B
    Returns:
        (bool, str) - bool - true if everything was succesfull false if it was not
                          str - None if no error occurred, otherwise an error message
    """
    pass

Personally I think when starting a new project you should start in the project script library. Write your business logic functions, document those as I just showed above, and then all your GUI should ever do is gather the arguments that you then feed the functions your wrote. Same thing with any Gateway timer scripts or gateway scoped logic. The project library and scripts in it are the most straightforward thing to document and also happen to be the easiest thing to do version control on since it's plain text, unlike windows etc. An additional benefit is that if you need to call some existing business logic now in a second location, you already are setup to do that, and you don't have to copy and paste a long script from a button into a script library and rework it.

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I also use google doc strings. I don't really know how you would use doxygen. Are the python files accesible outside of the designer?

I have never used doxygen so I cannot give you any pointers on that.

Yes they are, on a Windows gateway you can go to C:\Program Files\Inductive Automation\Ignition\data\projects\YourProjectNameHere\ignition\script-python to see your scripts.

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I think there are various places to put notes in the designers. But I would not recommend it.

I like to create a document usually in Excel. It is where I document patterns, conventions, etc.. and make sure it is in a place others can access.

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Documenting the conventions of the project and then following those conventions consistently (and leaving comments where you don't and why you're not) is the best bang for your buck imo. Most explanatory power for the least amount of administrative work of documenting.

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Some thoughts from an IA perspective here:

This is a loose plan, so any ideas anyone has about how this should or could work are appreciated.

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