Import experiment to MindProbe but get "413 Request Entity Too Large" error

PazBarTal

Hello,

I used a local JATOS to edit and debug my experiment, and now I want to use MindProbe as an external server to pilot it on a few participants. I tried to follow the instructions described in the JATOS manual (https://www.jatos.org/Run-an-experiment-with-JATOS-Workflow.html). I exported the experiment and tried to import it via my account with MindProbe, but I got a "413 Request Entity Too Large nginx/1.18.0 (Ubuntu)" error.

The size of the .jzip file is 1,175,491 kb (I am using 736 figures during the experiment). Are there any ways to solve this problem? Specifically, is there a way to remove the size restrictions? Or can I make the file smaller without reducing the quality or the number of images? Does anyone have any other suggestions for addressing this issue?

Thank you,

Paz

kri

Hi Paz,

your .jzip is over 1 GB. That is a lot! Unfortunately we cannot remove the size restrictions on Mindprobe but you can easily do it on your own JATOS installation (it's this config property). You can try to reduce your image size but there I'm not an expert. Or you load you images from an external source - you know, static files do not have to be served by JATOS, they can come from everywhere. JATOS just adds some features, e.g. that only participants with a proper study code can load them. But if you are okay with that they are hosted somewhere else, go for it.

Best,

Kristian

PazBarTal

Hi Kristian,

Thanks for your suggestions! I just wanted to ask if you know what the size limitations are for importing an experiment. It will help me choose my options.

Thank you again for your fast and informative response!

BW,

Paz

kri

The upload limit on MIndprobe seems to be 500MB.

And I have to correct myself: the proper way to set this in your own JATOS server would not be in the jatos.conf like I said before. In the jatos.conf one can limit only the result data size. The study's .jzip isn't limited by JATOS - usually this is limited by the reverse proxy in front of JATOS. With nginx it would be the client_max_body_size, e.g. "client_max_body_size 500M;" sets it to 500 MB.

K.

PazBarTal

Thank you so much!

I succeeded to compress my figures to reach the limit! (I used 'pngquant', if anyone encounters a similar problem).