Non-root proxy

Task

To build Apache 2 & mod_perl 2 for ePrints 3, installed as a standard user, with no superuser-like access to core services (including Perl and mySQL). The ePrints server will run as a normal user, and be accessed through a central proxy

Preparation

As we are installing software as a normal user (I'll use MyUser in this example), we are not adding any additional Perl modules centrally, but into a local tree. We need a directory to install this tree:

%> mkdir ~/perl5

We also need to be able to install some Perl packages from CPAN, so we need a configuration for that:

To set up cpan install as a non-root user, you need to set up your own ~/.cpan/CPAN/MyConfig.pm file. Copy one from another user, or find the system-wide one. You need to edit the values of a few keys in $CPAN::Config:

• 'build_dir', 'cpan_home', & 'keep_source_where' all need to be set to the full path for the users .cpan directory (eg: 'build_dir' => q[/home/MyUser/.cpan/build], )
• 'makepl_arg' needs to be set to PREFIX=/home/MyUser/perl5

You will need to set up a PERL5LIB environment variable for the shell (to run the various ePrints scripts). The easy way to work out what you need here is to see what the default library path is, and modify it for your user:

%> perl -V
Summary of my perl5 (revision....
[snip]
  @INC:
    /some/path/lib/perl5/5.8.0/sun4-solaris
    /some/path/lib/perl5/5.8.0
    /some/path/lib/perl5/site_perl/5.8.0/sun4-solaris
    /some/path/lib/perl5/site_perl/5.8.0
    /some/path/lib/perl5/site_perl

(This was developed on a Sun box, you may have something different to sun4-solaris)

We replace "/some/path" with the path to our new PREFIX (as defined above):

%> export PERL5LIB=/home/MyUser/perl5/lib/perl5/site_perl/5.8.0/sun4-solaris/: \
            /home/MyUser/perl5/lib/perl5/5.8.0/sun4-solaris: \
            /home/MyUser/perl5/lib/perl5/5.8.0: \
            /home/MyUser/perl5/lib/perl5/site_perl/5.8.0/MyUser: \
            /home/MyUser/perl5/lib/perl5/site_perl/5.8.0: \
            /home/MyUser/perl5/lib/perl5/site_perl

Add this to the users login/profile scripts (eg .bashrc)

Now we can start installing software.

Apache

Install a base Apache (previously downloaded into ~/distributions):

%> cd ~/distributions/
%> tar xvf httpd-2.2.x.tar
%> cd httpd_2.2.x

If you are returning to an existing source-tree, rather than a brand new untar'd bundle, clear any previous setup:

%> make distclean

Now configure and install an initial Apache server:

%> ./configure --prefix=/home/MyUser/www --disable-userdir --disable-status
%> make
%> make install

Edit http.conf (essentially, the port the server is listening on) and start the web server. Check the error log:

%> cat ~/www/logs/error_log
[...] Apache/2.2.x (Unix) Configured -- resuming normal operations

Mod-Perl

Stop web server and install the Mod-Perl extensions (previously downloaded into ~/distributions):

%> cd ~/distributions/
%> tar xvf mod_perl-2.0-current.tar
%> cd mod_perl-2.0.x

If you are returning to an existing source-tree, rather than a brand new untar'd bundle, clear any previous setup:

%> make clean 

Now configure and install mod-perl into the Apache tree, and (re)install Apache. In this example, I am specifying a version of Perl to use:

%> /path/to/specific/perl Makefile.PL PREFIX="/home/MyUser/perl5" MP_USE_DSO=1 \
   MP_APXS="/home/MyUser/www/bin/apxs" \
   MP_AP_CONFIGURE="--prefix=/home/MyUser/www --disable-userdir \
   --disable-status --enable-module=mod-perl"
%> make
%> make install

NOTE: Notice that there is a PREFIX defined, which matches the prefix in the CPAN configuration; that we are stating we want mod-perl as a DSO; the full path to the previously installed Apache "apxs" command; and that the configure parameters to be passed to the apache rebuild include enabling mod-perl

Editing the new apache config file

We need to enable the mod-perl module, which I do using one of the Includes:

• In ~/www/conf/httpd.conf, add:

# Mod-Perl
Include conf/extra/httpd-perl.conf

• Create ~/www/conf/extra/httpd-perl.conf:

#
# Load the Mod_perl DSO.
#
LoadModule perl_module modules/mod_perl.so
PerlSwitches -I/home/MyUser/perl5/lib/perl5/site_perl/5.x.y/sun4-solaris/ \
             -I/home/MyUser/perl5/lib/perl5/5.x.y/sun4-solaris \
             -I/home/MyUser/perl5/lib/perl5/5.x.y \
             -I/home/MyUser/perl5/lib/perl5/site_perl/5.x.y/sun4-solaris \
             -I/home/MyUser/perl5/lib/perl5/site_perl/5.x.y \
             -I/home/MyUser/perl5/lib/perl5/site_perl

• NOTE: the "PerlSwitches" line tells the Apache server where to look for extra libraries, and matches the PERL5LIB environment variable set earlier.

Start the web server. Check the error log:

%> cat ~/www/logs/error_log
[...] Apache/2.2.x (Unix) Configured -- resuming normal operations
[...] caught SIGTERM, shutting down
[...] Apache/2.2.x (Unix) mod_perl/2.0.x Perl/v5.x.y configured -- resuming normal operations

Stop the web server again.

---

ePrints

Before you can install ePrints, you need to check the Package requirements. CGI.pm builds against the installed Mod-Perl modules, so may well be wrong. You may need to install your own version.

eg:

%> /path/to/specific/perl -MCPAN -e shell
[snip]
cpan> install CGI
[...]
cpan> quit

Now we can install the ePrints software (previously downloaded into ~/distributions):

%> cd ~/distributions/
%> tar xvf eprints-3.zzz.tar
%> cd eprints-3.zzz./

There is no option to clean a previously configured eprints tree, so keep going..

%> ./configure -prefix=/home/MyUser/ePrints -with-perl=/path/to/specific/perl -with-user=MyUser \
    -with-group=MyUserGroup -with-toolpath=/path/to/tools

Note: the same version of perl is being defined again, and the /path/to/tools is a directory to find various external tools (tar, wget, (g)unzip, pdftotext, lynx, etc)

... and install:

%> ./install.pl

As we do not have root access to the MySQL database, you will need to get the database administrator to add a user to provide access the MySQL database. Note: Assuming your user is not given GRANT ALL (its a big security risk) you will need CREATE TEMPORARY TABLES as well as CREATE privilages.

Now we set up out basic ePrints environment

The trick here is to install the eprint application to match the web server (installed above), and then alter the core configuration to reflect the proxy settings.

%> cd /home/MyUser/ePrints

I needed to disable the "Disk Free" calls, and set up the routing for "smtp mail". We also know that the service is going to run as a local user, so the file and directory permissions need to be altered

These are all defined in the file perl_lib/EPrints/SystemSettings.pm:

$EPrints::SystemSettings::conf = {
                                       // snip //
                                   'smtp_server' => 'smtp.host.org',
                                   'file_perms' => 0640,
                                       // snip //
                                   'disable_df' => 1,
                                       // snip //
                                   'dir_perms' => 0775

In EPrints 3, all the configuration is done using the bin/epadmin.

You also need to decide the ARCHIVEID now, as this is used all over the place

• Initial configuration

The command to create the basic framework for a repository is:

bin/epadmin create

• When asked Configure vital settings? [yes] ?, say "Yes" and fill in the details
  • Hostname? is the actual address of the web server created above, not the public address (we fix that later)
  • Webserver Port [80] ? is the actual address of the web server created above, not the port for the web server (we fix that later)
  • Archive Name [Test Repository] ? is the name that the EPrints.org system will use when it dynamically supplies the archive name (using the <epc:pin /> coding)

• When asked Configure database? [yes] ?, say "Yes" and fill in the details
  • Database Name is the name of the database created for you by the database admin people
  • MySQL Host is the hostname for the server
  • MySQL Port MySQL Socket can probably be left blank, but check with the database admin people
  • Database User Database Password is as per agreed with the database admin people
• Create database "Deposit" NO - you can't, as we don't have that level of access to the database.
• Create an initial user? Yes
• Do you want to build the static web pages? Yes - this will create the default web pages, useful so we can check that the repository is running.

  We can alter the look'n'feel of the site later.

• Do you want to import the LOC subjects? Yes - again, this can be changed later, once we have checked we have a basic system up and running.
• Do you want to update the apache config files? Yes

Configuring the install for the proxy:

Now edit httpd.conf to include the generated apache.conf:

# EPrints
Include /home/MyUser/ePrints/cfg/apache.conf

Finally, I had to make a couple of other changes to make the service work:

1. Move the document root and cgi-bin stuff from the httpd.conf file (the name and the <directory> section)

1. Add access permissions to the <Directory "/home/MyUser/ePrints/cgi"> section in ePrints/archives/<ARCHIVEID>/cfg/auto-apache.conf:

    Order deny,allow
    Allow from all

Start web server. Check the error log:

%> cat ~/www/logs/error_log
[...] Apache/2.2.0 (Unix) Configured -- resuming normal operations
[...] caught SIGTERM, shutting down
[...] Apache/2.2.0 (Unix) mod_perl/2.0.2 Perl/v5.8.0 configured -- resuming normal operations
[...] [notice] caught SIGTERM, shutting down
EPrints archives loaded: <ARCHIVEID>
EPrints archives loaded: <ARCHIVEID>
[...] Apache/2.2.0 (Unix) mod_perl/2.0.2 Perl/v5.8.0 configured -- resuming normal operations

GLORY IN YOUR NEW EPRINTS SYSTEM!!!!

To modify the general layout of the page, edit ePrints/archives/<ARCHIVEID>/cfg/template-en.xml and then re-run .../bin/generate_static <ARCHIVEID>

Stuff from the eprints 2 version

>> the following is from eprint 2. it should not be needed in eprints 3, but I've not confirmed its surplus yes<<

• Configuration files modifications

We need to make some changes to the basic ePrints install 'cos we are running through a proxy, and the eprints install doesn't cope with this...

We have to change one EPrints configuration file so all the software processes to be run in the future correctly implement the base URL we want to deploy (http://public.server.name/). The change required is simply commenting code lines and including a new one, as you can see below:

edit archives/ARCHIVEID/cfg/ArchiveConfig.pm, in the section "Server of static HTML + images, including port"

# Server of static HTML + images, including port
# $c->{base_url} = "http://$c->{host}";
# if( $c->{port} != 80 )-]
# {
#     # Not SSL port 443 friendly
#     $c->{base_url}.= ":".$c->{port};
# }
# $c->{base_url} .= $c->{urlpath};
$c->{base_url} = "http://public.server.name/";