Process Model getting incorrect data from an Expression Rule

Question

I have an expression rule that returns a value based on rule inputs. 
 When I run this rule as a stand alone rule, it gets the data I expect. When I run this rule in process model A, I get the result I expect. But when I run the rule in process model B, I don't get the results I expect. 
 These 2 process models are child processes that get called at the same time, and have the same inputs. The node that runs the rule has the exact same inputs, settings, assignments, etc. 
 I can't see any reason why the rule would work correctly when run manually, or when run from process model A, and not process model B. For context, they are expected to return the same value in both process models. 
 Am I missing something? 
 If it helps, I'm using Appian Cloud v22.3

andrewm231 · Accepted Answer

My apologies, we found a resolution for this, and I forgot to post an update.

naveenkumar11800 · Answer

Hi Nourhan, 
 Ah, the classic 'it works when I run it manually, but not when the script task does it'&mdash;it's like trying to explain to your team why the printer jams only during presentations! 
 If the expression rule behaves perfectly in isolation but throws a tantrum when called in a script task, here are a few things to check: 
 Inputs, Inputs, Inputs: Double-check if the script task is passing the same values you tested with. Sometimes, a tiny mismatch or a missing input sneaks in and causes all the drama. 
 Timing is Everything: If the script task is running alongside other nodes, ensure the data it needs is ready when it starts. Parallel processes love to race ahead before the data shows up to the party. 
 Log It Like It&rsquo;s Hot: Add some logging to see what&rsquo;s going into the rule and what&rsquo;s coming out. It&rsquo;s like setting up surveillance cameras for debugging&mdash;very handy! 
 Environment Mood Swings: Occasionally, process models seem to act differently depending on how they're triggered (manual vs. automated). Maybe the script task needs a pep talk? 
 Andrew, if you're reading this, we&rsquo;re all curious about your resolution. Care to share the magic sauce? Nourhan, let us know if this helps or if there&rsquo;s more to the mystery&mdash;happy to help crack it!

naveenkumar11800 · Answer

Ah, that makes sense now&mdash;thanks for clarifying! Running the script task alongside a user input task could indeed cause issues if the necessary data isn&rsquo;t ready when the script task starts. 
 Your idea of adding a timer until the user input task is initiated is a smart workaround to avoid data timing issues. Just keep in mind: 
 Timer Duration: Make sure the delay is long enough to ensure all necessary data is available but not so long that it slows down your process unnecessarily. Data Validation: If possible, add a check in your script task to confirm the data is populated before proceeding. This can act as a safeguard in case the timer doesn&rsquo;t fully resolve timing issues. It sounds like you&rsquo;re on the right track&mdash;let us know if this completely resolves the issue or if you run into any more hiccups!"

Process Model getting incorrect data from an Expression Rule

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