Javascript error in Zapier: Undefined property access issue

Other Questions Zapier
1

Hey everyone! I’m new to coding and I’m having trouble with a Zapier JavaScript task. I’m trying to change a date format from a Woocommerce event. Here’s my code:

function formatDate(input) {
  if (!input) return '';
  
  let commaIndex = input.indexOf(',');
  
  if (commaIndex > 0) {
    return input.slice(commaIndex + 1, commaIndex + 12).trim();
  } else {
    return input.slice(0, 10);
  }
}

let formattedDate = formatDate(inputData.RawDate);
output = [{ firstLessonDate: formattedDate }];

The problem is, sometimes the RawDate isn’t set, and I get an error about not being able to read ‘indexOf’ of undefined. Am I right about what’s causing this? Should I check if the variable exists first? How can I fix this? Thanks for any help!

2

hey gizmo, looks like ur on the right track! yea, checking if the variable exists first is a good idea. try adding a check at the start of ur function like:

if (!input || typeof input !== ‘string’) return ‘’;

this should catch undefined inputs n prevent that error. hope it helps!

3

You’re correct about the cause of the error. The issue arises when RawDate is undefined, leading to the ‘indexOf’ method being called on an undefined value. To resolve this, you can add a type check at the beginning of your formatDate function. Here’s a modified version that should work:

function formatDate(input) {
  if (!input || typeof input !== 'string') return '';
  
  let commaIndex = input.indexOf(',');
  
  return commaIndex > 0 ? input.slice(commaIndex + 1, commaIndex + 12).trim() : input.slice(0, 10);
}

This approach ensures that the function only processes valid string inputs, preventing the error you’re encountering. Additionally, I’ve streamlined the return statement using a ternary operator for conciseness.

4

I’ve been working with Zapier for a while now, and I’ve run into similar issues. Your instinct about checking if the variable exists is spot on. Here’s a trick I’ve learned that might help:

Instead of modifying your formatDate function, you could handle the potential undefined input right when you call it. Try something like this:

let formattedDate = inputData.RawDate ? formatDate(inputData.RawDate) : ‘’;

This way, if RawDate is undefined or null, you’ll just get an empty string instead of an error. It’s a neat little shortcut that’s saved me a bunch of headaches.

Also, don’t forget to test your zap thoroughly with different inputs. Zapier’s debug mode is a lifesaver for catching these kinds of issues before they become problems in production. Good luck with your project!