Event handler not recognizing response item property

App ID 4A47197B-AE30-FA84-FF56-0071F4010900

Since yesterday, without changing any logic, my event handlers are not working.

I am printing the response item and then a property of the response item.

While the property is clearly in the response item object (highlighted below), it printing as undefined.

Hello @Andreas_Marinopoulos

I apologise for the inconvenience. I tried to reproduce the problem in my app, but to no avail. If the problem is still present, how can I reproduce it in your app? Can I add a test entry to the table “not_available”?


Yes please.


Everything seems to be working as it should now. Try checking on your side. Do you still see the problem?


@Inna_Shkolnaya it seems to be okay now. May I ask what the issue was?

It is related to an upgrade of the infrastructure we have to perform in order to support the growth of the platform.


Might you also have restored some code? We are finding some methods having older code in them. Please do not restore old versions of our code.

Can you somehow find from your logs if this method has been recently restored by you to an older version?


We haven’t done any rebuilding or changed the logic in your application. Can you tell us when you noticed that the logic was old? Is there any chance that the new logic has not been published?


@Inna_Shkolnaya When we create new methods, we add this if statement to them. This refers to a property of our customer objects. And this ID is our test customer.

When we set methods live, this if statement filter is removed. The said method has been live for over a month. And it has been working properly. So it is very strange to find this filter there again. I am certain we had removed it otherwise the method would not be running.


Please provide us with information on what this service and method are. (If it is a UI-builder, the name of the container, page, and block, as well as the name of the handler)


It is a backend event handler. All my issues were with event handlers and timers. But the error is gone now, I cannot replicate it. I will let you know if it happens again.

Do you have the logic you expected to have now? We haven’t changed anything. I am curious what happened on your side that the logic is reverted to the latest?

The old and new logic were exactly the same, except that the old logic contains this filter that we use when we test.

It is strange that the filter just reappeared.

We are getting this issue again on almost all event handlers in our app.

Continuous errors like: “Cannot read property ‘replace’ of undefined”. This is an example.

I understand this is related to your virtualization efforts, but could you stop it from happening?? We use event handlers everywhere and this is wreaking havoc and corrupting our data in a big way.

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We are experiencing this type of error once more. This time it is on a timer upcoming sessions.

We are getting an error of "Cannot read property 'replace' of null". Hoewever the property is not null.

Is it a property for an object fetched from the database? If so, what is the name of the table? What is the query to get the objects?

Yes, we are looping through objects from the calendar table.

The query is filtering for a timestamp:

If that is a potential cause, we can maybe try using <> or other formats.

The loop then takes one object at a time



In your previous message you talked about the “replace” property, but here I don’t see any references to it. Could you please clarify?


In the logic I also can see two more replace, for properties url and tutor

with url there won’t be the problem because you create it in the logic,

but tutor value comes from the server and some of your records don’t contain the value and it also can throw an exception

also, in the calendar table there are 3 records without slots_slug value

so, could you please make sure that you use the Replace block with no-null value

Indeed @mark-piller the error we are getting is


I am assuming it related to this:

But not sure.

Recent runs have been working however, no errors in the last few minutes.