REST API html request doesn't work

Hi,

I have installed the REST API plugin and I want to add and create users via html request.

Therefore I tried some examples out of the readme. Something like this:

http://example.com:9090/plugins/restapi/userservice?type=grouplist&secret=bigsec ret

http://example.com:9090/plugins/restapi/userservice?type=add&secret=bigsecret&us ername=jodibla&password=jodibla&name=jodibla

Only to be sure I used my url instead of example.com and I also used the value from plugin.restapi.secret for the secret.

The result is that I only get a blank page back.

How can I analyze why nothing happens? Are there any logs?

Thanks for your help.

jodibla