JATOS server and static folder on Apache2

Comments

• kri

  June 3

  Hi Jason,

  I see since JATOS creates unique URLs each time, so that caching is not possible.

  That is correct. But JATOS additionally to the file serving does some authorization. Only participants currently running a study are allowed to access the files in the study assets folder. If you have some files there that not everyone should be able do access, e.g. trial data, this is what you want. On the other side if you have just 'normal' files, like images or videos, there is no reason to not put them somewhere else, e.g. in some folder where Apache can do the delivery faster.

  We (actually my local IT genius) have been working with the apache2 CONF file and have had no luck getting this work.

  I tried a bit to get this work but failed too. I'm not much of an Apache expert, I guess. It shouldn't be too difficult though, one part of the requests get delivered by Apache as static files and the other part get proxied to port localhost:9000 where JATOS lives. My config looks something like this, but somehow the static files do not get delivered.

  <VirtualHost *:80>
    ServerName example.com
    ServerAlias www.example.com
  
    Alias /static/ /var/www/html/
    <Directory /var/www/html/>
      Options Indexes FollowSymLinks
      AllowOverride None
      Require all granted
    </Directory>
  
    ProxyPass /static/ !
  
    # JATOS uses WebSockets for its batch and group channels
    RewriteEngine On
    RewriteCond %{HTTP:Upgrade} =websocket [NC]
    RewriteRule /(.*)           ws://localhost:9000/$1 [P,L,UnsafeAllow3F]
    RewriteCond %{HTTP:Upgrade} !=websocket [NC]
    RewriteRule /(.*)           http://localhost:9000/$1 [P,L,UnsafeAllow3F]
  
    # Proxy everything to the JATOS running on localhost on port 9000
    ProxyPass / http://localhost:9000/
    ProxyPassReverse / http://localhost:9000/
  </VirtualHost>
  

  Please tell me when you figured it out. I'm curious!

  Best,

  Kristian
• steffejr

  June 17

  Hello Kristian,

  Sorry for the delay, but Jarno (my local IT genius) figured it out.

  We made the following folder where I put my unchanging files that can be cached: /var/www/html/static/

  I will put most of the jspsych Javascript code that I use in there.

  For each file I want loaded (and cached) I make the following change within my HTML files. (In this example I just copied my entire jspsych folder into the static folder).

  <script src="jspsych/dist/jspsych.js"></script>
  

  to

  <script src="/static/jspsych/dist/jspsych.js"></script>
  

  
  

  NOTE: when you are testing this to make sure it works and using the Chrome developer tools, make sure you do NOT have the "Disable cache" button checked.

  
  

  The following is my conf file

  <MDomain mydomain.ca>
    MDCertificateAgreement accepted
  </MDomain>
  
  
  <VirtualHost *:80>
    ServerName mydomain.ca
    ServerAdmin my@email.ca
    # Redirect all unencrypted traffic to the respective HTTPS page
    Redirect "/" "https://mydomain.ca"
  
  
  </VirtualHost>
  
  
  <VirtualHost *:443>
    ServerName mydomain.ca
    ServerAdmin my@email.ca
    # Restrict access to JATOS GUI to local network
    #<Location "/jatos">
    #  Order deny,allow
    #  Deny from all
    #  Allow from 127.0.0.1 ::1
    #  Allow from localhost
    #  Allow from 192.168
    #</Location>
  
  
    # Your certificate for encryption
    SSLEngine On
  
  
  ProxyPass /static !
  Alias /static /var/www/html/static
  
  
    # JATOS uses WebSockets for its batch and group channels
    RewriteEngine On
    RewriteCond %{HTTP:Upgrade} =websocket [NC]
    RewriteRule /(.*)           ws://localhost:9000/$1 [P,L,UnsafeAllow3F]
    
    RewriteCond %{REQUEST_URI} !^/static.*
    RewriteCond %{HTTP:Upgrade} !=websocket [NC]
    RewriteRule /(.*)           http://localhost:9000/$1 [P,L,UnsafeAllow3F]
  
  
   # Proxy everything to the JATOS running on localhost on port 9000
   #  DocumentRoot /var/www/html
  	ProxyPass / http://localhost:9000/
          ProxyPassReverse / http://localhost:9000/
  </VirtualHost>
  
  
  

  
  

  I hope this helps,

  Jason
• kri

  June 17 edited June 24

  Hi Jason,

  I was missing the RewriteCond for the static folder! And the ProxyPass and ProxyPassReverse isn't necessary since we use the RewriteCond.

  Just for local development, if someone else is interested and for my own reference, I add an Apache config for port 80 without encryption. I put it under /etc/apache2/sites-available/example.com.conf.

  ServerName www.example.com
  
  <VirtualHost *:80>  
    RewriteEngine On
  
    # JATOS uses WebSockets for its batch and group channels
    RewriteCond %{HTTP:Upgrade} =websocket [NC]
    RewriteRule /(.*)           ws://localhost:9000/$1 [P,L]
  
    # Rewrite condition for static files
    RewriteCond %{REQUEST_URI}  !^/static.*
    # Rewrite condition for everything else
    RewriteCond %{HTTP:Upgrade} !=websocket [NC]
    RewriteRule /(.*)           http://localhost:9000/$1 [P,L]
  </VirtualHost>
  

  Thanks for posting this here. I'll update JATOS docs.

  Best,

  Kristian

  EDIT: See Apache Docs