Create a monitor that fails if a specific field contains null

[Kevin4]

Hi, this is probably a basic question but I am new to Dynatrace. I have an endpoint that is returning a 200 when 2 required fields are null. We are not yet sure where the bug in the code is but want to monitor the rare exception this happens.  The JSON response is similar to:

{

    "requiredOne" : null,

    "requiredTwo" : null

}

Will this be as simple as setting the two rules below?

pass if 200

fails if contains text "requiredOne" : null

or should I use regex? Thank you for any suggestions.

[MichalOlszewski · Accepted solution]

Hi @Kevin4 

I'm assuming that You are Client side of this communication. Then Yes You can create monitor tracking those fields - I would personally go regexp as You can do it all in one go and still should be relatively simple.
IF You have access to Server-Side of this communication then I would recommend creating RequestAttributes that captures those values before sending them - this way You would be able to use multidimensional analysis to narrow down cases where those double null happens. Making this capturing from real traffic at the same time will allow You to find all potential reasons behind them.