Get the code from the git repository

The web application code can be placed in any directory, e.g. OPUS_DIR=/opt/OPUS. To create the OPUS directory, clone the git repository:

$ git clone

Prepare local configuration

Several files contain initial settings that should not be modified. However, a file in the OPUS directory, will overwrite any settings. One should thus create such a file, using the template provide.

$ cd $OPUS_DIR
$ cp

This file must be edited to setup confidential tokens and defaults passwords, and any specific configuration of OPUS (Storage, SLURM...). See the page for Settings.

Note that OPUS stores its logs, files and database in a dedicated directory, e.g. OPUS_VAR=/var/opt/opus.

Setting the environment

OPUS has been tested on MacOS, Debian/Ubuntu and CentOS. The web application generally uses Apache 2 and the WSGI module connected to a Python 3.6 environment.

The following packages may be needed if not already installed in the environment: git, bzip2, graphviz, httpd-devel, perl-Digest-SHA (e.g. for CentOS, using yum install`).

The Python 3 environment used in all cases installed with the Anaconda distribution (check the A virtual environment should be created, e.g. with the following commands:

$ cd $OPUS_DIR
$ conda create --name wsgi36 python==3.6
$ conda activate wsgi36
$ pip install -r pip-requirements.txt

The WSGI module should then be installed within this virtual environment, and a wsgi.conf file generated to setup the Apache web server:

$ pip install mod_wsgi
$ mod_wsgi-express module-config
$ mod_wsgi-express module-config > wsgi.conf

OPUS then requires a directory to store its logs, files and database, e.g. OPUS_VAR=/var/opt/opus. This directory must be writable from the web application, i.e. by the user Apache is running as (e.g. www, www-data or apache). The $OPUS_VAR/logs directory must also be created and writable for this user, if the logs are written in this directory (see Apache configuration proposed below).

The unit tests may be run to check the main features of the UWS server:

$ make test

Web server configuration

The uws_server/ file can be directly run to test the application on localhost:8080.

With Apache 2 and mod_wsgi, use the script uws_server/ or create a similar script. In the same way, the client can be run directly (uws_client/ or using the script uws_client/ For convenience, the following links can be created:

$ cd $OPUS_DIR
$ ln -sf uws_server/
$ ln -sf uws_client/

Apache should be setup by providing the necessary .conf files in the APACHE_CONF directory (e.g. for CentOS this directory should be APACHE_CONF=/etc/httpd/conf.d/; for Debian/Ubuntu, the files should be placed in /etc/apache2/sites-available/ with a link from /etc/apache2/sites-enabled/, for MacOS the file can be copied to /etc/apache2/other/).

First copy the WSG module configuration (as root):

# cp wsgi.conf $APACHE_CONF

Then create a opus.conf file to define virtual hosts for the OPUS server and client (in $APACHE_CONF for example, or inside /etc/apache2/extra/httpd-vhosts.conf for MacOS), the content would then be:

<VirtualHost *:80>
    DocumentRoot /opt/OPUS
    ErrorLog "/var/www/opus/logs/apache_error.log"
    CustomLog "/var/www/opus/logs/apache_access.log" combined
    Header set Access-Control-Allow-Origin "*"
    WSGIDaemonProcess opus_client display-name=%{GROUP} processes=1 threads=5
    WSGIScriptAlias /opus_client "/opt/OPUS/" process-group=opus_client
    WSGIDaemonProcess opus_server display-name=%{GROUP} processes=1 threads=5
    WSGIScriptAlias /opus_server "/opt/OPUS/" process-group=opus_server
    Alias /static "/opt/OPUS/uws_client/static"
    WSGIPassAuthorization On
    <Directory "/opt/OPUS">
        AllowOverride None
        Require all granted

After this configuration, the server must be restarted, and logs checked:

# apachectl restart
# apachectl

SLURM Work Cluster configuration

In order to send and manage jobs on a SLURM Work Cluster, the UWS Server must be specifically configured.

A dedicated account must be defined on the SLURM Work Cluster and declared in the UWS Server settings. This account must be accessible through SSH by copying the UWS Server SSH public key in the .ssh/authorized_keys file on the SLURM Work Cluster dedicated account home directory.

The oncompletion plugin can be added to SLURM to send a signal on specific SLURM events (TIMEOUT, PREEMPTED, ...). This is done by adding in the dedicated script (e.g. /usr/local/sbin/ a curl command for the SLURM account (<UID>) that sends a signal to the <BASE_URL> as follow:

if [[ "$UID" -eq <UID> ]]; then
    curl -k --max-time 10 -d jobid="$JOBID" -d phase="$JOBSTATE" <BASE_URL>/handler/job_event