Event rule for 'object update' however it always gets triggered if a field is edited.

[G0nz0uk]

Hello,

I have an event rule for our devices. Like this below.

condition is

{
    "and": [
        {
            "attr": "custom_fields.TOC_status",
            "value": false
        }
    ]
}

This is what it looks like in a device:

If I edit the device and do nothing to it and hit save I get a webhook alert.

The event is looking for the boolean to = false

Any ideas how I can get this working correctly?

Update: It does the same for True too.

I'm guessing it's just reading all the object data as 'new' data when saved.

We can't do anything like this can we?

{
    "and": [
        {
            "attr": "custom_fields.TOC_status",
            "value": true
        },
        {
            "attr": "custom_fields.TOC_status_changed",
            "value": true
        }
    ]
}

Thanks

[pheus]

Side note: since your recent discussions all seem to be about the same event rule/condition topic, it’s usually easier to follow (and answer) if you keep it in a single thread and add updates there.

From the docs:

An event rule may include a set of conditional logic expressed in JSON used to control whether an event triggers for a specific object. For example, you may wish to trigger an event for devices only when the status field of an object is "active"

The key point is: the condition is evaluated against the object’s state when the update event occurs. It does not mean “only trigger when this field changes.”

So if you save the device (even without changing anything), that still counts as an object update, and if custom_fields.TOC_status is false (or true), the condition is still satisfied and the rule triggers.

[G0nz0uk]

Thanks

What's interesting if I set that Boolean field to 'null' (instead of true or false) and save then the event rule is not triggered. That description suggests it should be, but I'm please it's not as it may help is in this scenario.

[pheus]

I wouldn’t recommend relying on that behavior. If setting the boolean to null prevents the rule from triggering, that may be an implementation detail, a bug, or simply undefined behavior rather than something guaranteed by the docs.

In other words: it could change at any time (e.g., with an upgrade), so I’d avoid building automation that depends on it.

[G0nz0uk]

I wonder if I need to write something instead then using Djang and run as a Cronjob. So look for a previous for just that field and if it has changed on the next run then send a message to Teams/email.

[pheus]

I’m not entirely sure what your end goal is, but you shouldn’t need a cronjob for this. NetBox can already trigger on object updates.

What you do need is a way to check whether the specific field changed, and only act when it did. In the webhook payload, NetBox provides the object state before and after the change (the pre-change and post-change snapshots), so your receiver/script can compare those values and decide whether to send a Teams/email notification or ignore the event.

[G0nz0uk]

Netbox doesn't seem to read the previous state we have or my event trigger is wrong.

We have a custom field which is a boolean and called 'TOC Status'.

I have an event object change to trigger if this changes to True and another to False which works.

However if you edit a device and make no changes at all and just hit save it still triggers the event. We want the event to only trigger if the it's previous state was different to the new one.

I'm using:

{
    "and": [
        {
            "attr": "custom_fields.TOC_status",
            "value": true
        }
    ]
}

and another event for

{
    "and": [
        {
            "attr": "custom_fields.TOC_status",
            "value": false
        }
    ]
}

When I just save the object making no changes I see this in the change log where it sees all the custom_field block as 1 object it seems.

We import other data into here from an API, I wonder which does change so I wonder if it sees this as a change and not just the TOC_status?

Basically my goal is - to set a devise to 'TOC' or 'Active' (True/false) and fire a webhook and not look at the other JSON data for that object.

[G0nz0uk]

I was testing on just the status field too and hoping snapshots were supported to look at previous status, but I read it's possibly not:

Event alert if it goes from staus = inventory to status = active only:

{
  "and": [
    {
      "attr": "status.value",
      "value": "active"
    },
    {
      "attr": "snapshots.prechange.status.value",
      "value": "inventory"
    }
  ]
}