Repeated IMLError > displayError when processing multiple operations

[Mq_Gestion]

Hey everyone,
I’m building an automated content pipeline on Make that pulls new articles from an RSS feed, generates images with DALL·E (via OpenAI, response format = URL), and posts everything directly to WordPress.

The flow looks like this:

RSS triggers every 15 minutes

For each article:

    DALL·E generates an image (URL returned)

    I fetch the image with HTTP Get a File

    Then I upload it to WordPress via Create a Media Item

    Finally, I create the post and attach the image as featuredMedia

Here’s the weird part:

The first operation works perfectly.
But if the scenario pulls 2, 3, or 4 articles in one go, the second or third operation always fails with:

IMLError
Function ‘displayError’ finished with error! Cannot read properties of undefined (reading ‘toString’)

I’ve already tried:

Adding Sleep (60s delay between cycles)

Filtering with length(data) > 1000

Validating file names

Creating fallback routes

Logging the buffers (they’re valid and non-empty!)

But somehow, Make still crashes when trying to push the image to WordPress on later operations.

My current theory:

Either Make lazily evaluates the data field and it’s not ready when WordPress tries to access it

Or the buffer becomes corrupted when multiple items are processed in a batch

Or WordPress doesn't like back-to-back media uploads

Any idea how to fix or stabilize this?

Has anyone run into the same issue?

Thanks in advance

Note:

[samliew]

Welcome to the Make community!

@Mq_Gestion

Function ‘displayError’ finished with error! Cannot read properties of undefined (reading ‘toString’)

Your Data variable is probably empty on that particular bundle.

Try adding a filter before to only allow bundles with Data through.

Hope this helps! Let me know if there are any further questions or issues. P.S.: investing some effort into the tutorials in the Make Academy will save you lots of time and frustration using Make!

— @samliew