Process of installing the
on a computer running Debian GNU Linux
This file describes the process of installing the PWS software
on a computer running Debian GNU Linux using the provided
installer PwsInstaller-perlX-glibcY.jar (X and Y denote the
version of you perl and glibc libraries).
Debian GNU Linux is a robust server-oriented Linux distribution.
Installing it is not really difficult, but requires good
unserstanding of what lies under the cover of your computer
and what you really want to use it for. We suppose, are
talking about the stable release.
Depending on how it has been installed, you will need
to add some components required by the PWS :
Please check that all the above is installed on your Debian
GNU Linux, and also check that the zlib package is actually
- a Perl interpreter,
- an Apache web-server
- and a Java Virtual Machine (a Development kit -- JDK -- or a Runtime Environment -- JRE).
Installing the required software
There are some chances that Perl is already installed
on your Debian GNU Linux distribution. If not, you need
to 'apt-get' the Perl package.
You need to remember where you installed it, as you will
be asked later.
The PWS works well with perl 5.6 or newer.
Apache is the most used web server on the Internet. Although,
it is a free software and you can easily install it on
'apt-get' apache and be aware that, in the case of a PWS-only
use, you will not need any additional components such
as php or perl modules.
The PWS has been successfully tested on version 1.3.2X
and 2.0.X of the Apache web server (the stable Debian
release, when writing the document, is shipped with version 1.3.27).
Refer to section 5.1 of the next chapter for PWS-specific
Java is required by the PWS to run the Drew tools (applets).
Java components are sometimes distributed as distribution
packages, but this is quite rare.
You can get a Java Virtual Machine (JVM) either from sun
or at BlackDown (Linux-only Java distributions) at
You can get either a full JDK or only a JRE, which is
smaller and contains everything needed to have the PWS
The PWS is made to run with Java 1.1.8 or earlier. It
is known to work well on version 1.3.1 and has been tested
with success on version 1.4.1.
3.1. Java as a plugin for your browser
In the case of the PWS, java is used as a plugin for your
To correctly install the java plugin for
you web browser, please refer to the Java documentation.
Installing the PWS
Here, you should already have downloaded the installer
archive called PwsInstaller-perlX-glibcY.jar. If not, please
The installer is launched by issuing the
java -jar PwsInstaller-perlX-glibcY.jar
Then, you only need to follow the steps described below :
1. Choosing your language, about the PWS and the license
The first thing to do is to choose the language you want
the installer speak into. This does not affect the language
of the final installation (where all the proposed languages
are installed), but only the one of the installer.
After that, a brief explanation of what the PWS is, is
displayed, and there comes the license panel. Please,
read carefully ,this license (the LGPL) and tell whether
or not you agree with the terms. You will then be able
to go on the installation process unless you do not accept
the terms of the license.
2. Choosing where to install the files
The next panel asks you where, on your filesystem, to
install the files of the PWS. At this point, you have
two main choices : whether you install this software in
the install directory of your Apache web server, whether
you install it in a its own directory. There is no preferred
way ; you choose.
To install it in the default Apache directory, you need
to enter the following path (which should already be given) :
If you do so, the pws directory will be created and everything
will be put there. Nothing will appear elsewhere.
The resulting file hierarchy will be as follow :
| +- pws (All the required xml and xsl files)
| +- classes (the Drew Client applets)
| +- pws (The xml engine)
+- classes (The Drew server)
+- libs (The Perl modules and some mandatory xml/xsl libs)
If you choose to install it elsewhere, only the root
directory will be altered, not the file hierarchy.
3. Giving the path to the Perl interpreter and choosing
how to access your installation through a web browser
The next panel asks you the last two questions of this
In the first part, you need to give the path where the
Perl interpreter is located (/usr/bin is correct most
of the time).
The second part, asks you to choose the URI, relative
to your web-server root, under which the PWS will be available.
This is something you choose depending on your local web-server
layout. Usually, the default '/pws' is OK, but you may
want to change it. Assuming the web-server of your machine
is reachable by the following URI :
the PWS will show under this one
So, when the installation is completed, you can access
the software by pointing a web browser to this URI.
4. Some clicks later...
The following panels are only informative and allow you
to check if what you have entered is correct, and to launch
the install itself.
The last panel creates an automatic installed, which is
useful if you want to duplicate the same installation
on other computers without having to retype everything.
5. What we get at the end
Once you have closed the installer, the biggest part of
the installation process is done. You end up with the
complete file hierarchy of the PWS copied to you computer,
a file named 'pws.conf' and an automatic uninstaller located
in the Uninstall directory, both at the root of your installation
(/var/www/pws if you chose the default).
But unfortunately, there are some few steps you have
to do by hand.
5.1. Modifying the Apache configuration
NOTE : all the steps below require super-user access.
You need first to tell Apache that some new documents
have been added to its hierarchy.
To acheive this, you need to modify the Apache configuration
file 'httpd.conf' in the /etc/httpd/ directory, by including
the directive found in the header of the 'pws.conf' file
(the one begining by Include).
Then you need to enable the use of some more modules.
To do so uncomment, in the same file, the lines related
to theses modules (they are mod_env, mod_action, mod_mime
Following are the lines to uncomment in the file :
LoadModule env_module libexec/httpd/mod_env.so
LoadModule action_module libexec/httpd/mod_actions.so
LoadModule mime_module libexec/httpd/mod_mime.so
LoadModule auth_module libexec/httpd/mod_auth.so
5.2. Restarting Apache
The last step is then to restart Apache. To do so, use
whether the 'init.d' script or, easier, the 'apachectl' (or 'apache2ctl',
or 'httpctl' or 'httpdctl') command.
You may want to first check the syntax of the file by issuing
a 'apachectl -t' command in a terminal window.
Using this command actually restarts the server and do
some more checking in the syntax of the config file.
Please note that restarting Apache is mandatory !
6. About passwords
The PWS site has several sub sites which can only be accessed
via password authentication (administration and teacher
The default login/passwords are :
- teacher/teacher for the teacher part
- admin/admin for the admin part
We strongly encourage you to change these defaults by
something less easy to guess. At this time, you need to
use the terminal to do it. The command to use is 'htpasswd',
and following is an example of how to use it (default
installation path is used for this example, adapt it to
your installation) :
htpasswd -m /var/www/pws/auth/pws.auth admin new_admin_password
htpasswd -m /var/www/pws/auth/pws.auth teacher new_teacher_password
Passwords created for students groups are stored in this
same file, but are created and modified via a web interface
inside the PWS.
Enjoy the PWS software !