I am using Katalon Studio 6.2.2 in Ubuntu.
During some API testing, I realized I was able to do GET without any problem but POST always returned me status 400 - Bad Request.
After some analysis, I realized that, no matter what I wrote in the HTTP Body section of my Object (see following picture), the request Katalon was sending was always empty, giving me the Bad Request all the time.
Then, after a long analysis (and looking at some older files I had) I solved the issue by adding a new line inside the “.rs” file of my Object, like the image below:
Here is the line I added manually to the file:
"text": "{\n "message": "${message_string}"}",
Of course you need to adapt the line according to the content you want to send.
I am using a variable called message_string in order to send different messages in my request.
I am pretty sure this line should be added automatically once you fill in the “HTTP Body” tab of the interface and therefore, I am considering it a bug.
Maybe it has something to do with the fact that I am using linux or maybe some missing configuration but I found this workaround to make things work for me.
Please let me know it this is indeed a bug or if there is a way I can fix it in an easier way, since it is pretty annoying that every time I save my Object I have to edit the .rs file again because the line I added gets automatically deleted.