Introduction to mod_perl (part 2): mod_perl Quickstart - Installing mod_perl Detailed (
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If you didn't have the
courage to try the steps in the previous section or you simply want to
understand more before you try, let's go through the fine details of the
installation process. If you have successfully installed mod_perl following the
short scenario in the previous section, you can skip this section and move on to
the next one.
Before we proceed, I should note that you have to become a
root user in order to install the files in a protected area. If you don't have
root access, you can install all the files under your home directory as well. We
will talk about the nuances of this approach in a future articles. I'll also
assume that you have perl and gcc or an equivalent C compiler
installed.
I assume that all builds are being done in the /home/stas/src
directory. So we go into this directory.
% cd /home/stas/src
Now we download the latest source distributions of Apache and mod_perl. If
you have the LWP module installed (also known as libwww and available from
CPAN), you should have the lwp-download utility that partly imitates your
favorite browser by allowing you to download files from the Internet. You can
use any other method to retrieve these files. Just make sure that you save both
files in the /home/stas/src directory, as this will make it easier for you to
follow the example installation process. Of course you can install both packages
anywhere on your file system.
% lwp-download http://www.apache.org/dist/httpd/apache_1.3.20.tar.gz
% lwp-download http://perl.apache.org/dist/mod_perl-1.26.tar.gz
You can make sure that you're downloading the latest stable versions by
visiting the following distribution directories:
http://www.apache.org/dist/httpd/ and http://perl.apache.org/dist/. As you have
guessed already, the former URL is the main Apache distribution directory, the
latter is the same thing for mod_perl.
Untar both sources. You have to
uncompress and untar the files. In addition to its main usage for tarring and
untarring files, the GNU tar utility is able to uncompress files compressed by
the gzip utility, when the -z option is used.
% tar -zvxf apache_1.3.20.tar.gz
% tar -zvxf mod_perl-1.26.tar.gz
If you have a non-GNU tar utility, chances are that it will be unable to
decompress, so you need to do it in two steps. First uncompress the packages
with:
% gzip -d apache_1.3.20.tar.gz
% gzip -d mod_perl-1.26.tar.gz
Then untar them with:
% tar -xvf apache_1.3.20.tar
% tar -xvf mod_perl-1.26.tar
If you don't have tar or gzip utilities available, either install them or
use their equivalents.
Now go into the mod_perl source distribution
directory.
% cd mod_perl-1.26
The next step is to create the Makefile.
% perl Makefile.PL APACHE_SRC=../apache_1.3.20/src \
DO_HTTPD=1 USE_APACI=1 EVERYTHING=1
mod_perl accepts a variety of parameters, in this scenario we are going to
use those that will allow you to do almost everything with mod_perl. Once you
learn more about mod_perl you will be able to fine tune the list of parameters
passed to Makefile.PL. In future articles I'll go through all the available
options.
perl Makefile.PL ... execution will check for prerequisites and
tell you which required software packages are missing from your system. If you
don't have some of the Perl packages installed, you will have to install these
before you proceed. They all are available from CPAN and can be easily
downloaded and installed.
If you choose to install mod_perl with help of
the CPAN.pm module, it will install all the missing modules for you. To do so,
tell CPAN.pm to install the Bundle::Apache bundle.
This step also
executes the ./configure script from Apache's source distribution directory
(absolutely transparently for you), which prepares the Apache build
configuration files. If you need to pass parameters to Apache's ./configure
script, just pass them as options to perl Makefile.PL .... In future articles we
will talk about all the available options.
Now you should build the httpd
executable by using the make utility.
% make
This command prepares mod_perl extension files, installs them in the
Apache source tree and builds the httpd executable (the web server itself) by
compiling all the required files. Upon completion of the make process you get
returned to the mod_perl source distribution directory.
make test
executes various mod_perl tests on the freshly built httpd executable.
% make test
This command starts the server on a non-standard port (8529) and tests
whether all parts of the built server function correctly. If something goes
wrong, the process will report it to you.
make install completes the
installation process of mod_perl by installing all the Perl files required for
mod_perl to run and of course the server documentation (man pages).
% make install
You can use the following commands concatenation style:
% make && make test && make install
It simplifies the installation, since you don't have to wait for each
command to complete before starting the next one. When installing mod_perl for
the first time, it's better to do it step by step.
If you choose the
all-in-one approach, you should know that if make fails, neither make test nor
make install will be executed. If make test fails, make install will be not
executed.
Finally, change to the Apache source distribution directory and
run make install to create the Apache directory tree and install Apache header
files (*.h), default configuration files (*.conf), the httpd executable and a
few other programs.
% cd ../apache_1.3.20
% make install
Note that, as with a plain Apache installation, any configuration files
left from a previous installation won't be overwritten by this process. You
don't need to backup your previously working configuration files before the
installation.
When the make install process completes, it will tell you
how to start a freshly built web server (the path to the apachectl utility that
is being used to control the server) and where the installed configuration files
are. Remember or even better write down both of them, since you will need this
information very soon. On my machine the two important paths
are:
/usr/local/apache/bin/apachectl
/usr/local/apache/conf/httpd.conf
So far we have completed the building
and installation of the mod_perl enabled Apache. The next steps are to configure
httpd.conf, write a little test script, start the server and check that the test
script is working.
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