HelpOnInstalling/ApacheOnUnix

Index

Installation when you are root or the webmaster

When you are root or the webmaster on the host you want to install MoinMoin on, you can place the software in a "standard" location, and also better integrate MoinMoin into your webserver. Especially, you can use a "nice" base URL that does not include "cgi-bin" or "moin.cgi" at all.

Most GNU/Linux distributions come with Apache pre-installed. In the following description, we assume a file system layout with:

• /etc/httpd/httpd.conf - the main httpd configuration file

• /var/log/httpd/error_log - log containing error messages

Installing MoinMoin

Before creating a wiki instance, you have to download and install the basic MoinMoin software. We assume you already have downloaded the distribution archive to "/tmp" ¹.

Open a shell and enter the following commands:

cd /tmp
tar xzf moin-1.1.tgz
cd moin-1.1
python setup.py install --record=install.log

This will install all necessary files into the sys.prefix directory of your Python interpreter (usually either "/usr" or "/usr/local"), and create a "install.log" file listing all the files that are created there. The command "python -c 'import sys; print sys.prefix'" will tell you where your Python interpreter is installed, we assume "/usr/local" here.

Creating a wiki instance

You could run your wiki directly using the sample wiki created in "/usr/local/share/moin", but this is not recommended for two reasons:

1. updating your wiki is more complicated and more dangerous.
2. creating a second wiki instance, even if you currently don't plan for one, is much easier.

We need to know what user and group your Apache server runs on, so issue this command:

jh@localhost:~ > egrep "^User|^Group" /etc/httpd/httpd.conf
User wwwrun
Group nogroup

This shows a typical result "wwwrun.nogroup", which we will use later on.

To create an instance named "mywiki", enter these commands on a root shell prompt:

cd /usr/local/share/moin
mkdir mywiki
cp -r data mywiki
cp cgi-bin/* mywiki
chown -R wwwrun.nogroup mywiki
chmod a+rx mywiki/*.cgi

"mywiki" is the name of your wiki instance, you might want to chose a different name best fitting the intended use of this instance; just don't name it simply "wiki", because that would result in problems later on.

Then, append these lines to "/etc/httpd/httpd.conf":

Alias /wiki/ "/usr/local/share/moin/htdocs/"
ScriptAlias /mywiki "/usr/local/share/moin/mywiki/moin.cgi"

The first line you only need once; the second line is needed once for each wiki instance (of course, each one with another wiki name and path).

That is all, restart your Apache server (usually "/etc/init.d/apache restart") and try to access your new-born wiki with the URL "http://127.0.0.1/mywiki/". You should see the FrontPage, try to edit and save it, and if that works, see if your edit is reflected on the RecentChanges page.

Finally, edit "moin_config.py" and at least change "sitename" and "logo_url" to some personal values:

sitename = 'My Wiki'
logo_url = '/images/mywiki-logo.gif'

For a personal or intranet installation, you'll normally also add the line

allowed_actions = ['DeletePage', 'AttachFile']

Troubleshooting

The first thing to do when your wiki does not work as expected is to issue the command "tail /var/log/httpd/error_log" to display the most recent errors. Usually, you will get a hint on what went wrong, like missing file system permissions. Also, always consult the HelpOnInstalling/TroubleShooting page for further hints on your problem.

Dueling Pythons

The most common problem you might encounter is when you have an old Python version installed into "/usr", and a newer Python distribution into "/usr/local"; this is typical for GNU/Linux distributions that still come bundled with an old Python version.

In that case, if you enter "python" on your prompt, you will usually get the more recent Python interpreter, because "/usr/local/bin" is in your PATH. The situation is different in your webserver environment, and thus you might have to change the bang path of "moin.cgi", like this:

"""
    MoinMoin - CGI Driver Script
...
"""

Distutils does not work

If you have problems with the distutils install step, note that you need to have the Python development package installed on some Unix distributions. On Mandrake, you need to "rpm -i python-devel-2.x.x-xmdk.i586.rpm".

Missing file permissions

If you are root, the installed files may be readable only by root, but they must also be readable by the web server before the wiki will work. This includes both the Python modules and the site itself. For the data directory, the web server also needs write access. To fix this, first find out where the Python module directory is; look in install.log, or run the command:

python -c "import sys; print '%s/lib/python%s/site-packages' % ( sys.prefix, sys.version[:3] )"

For the example below, we'll assume that the Python module directory is /usr/local/lib/python2.3/site-packages. Make the files world-readable using the following commands:

cd /usr/local
chmod -R a+rX lib/python2.3/site-packages/MoinMoin share/moin

Note that by making everything under /usr/local/share/moin world-readable, local users can read the files containing your wiki. You don't really need to do that, since the mywiki directory is owned by the webserver. If you don't want that, you do a "chmod -R o-rwx share/moin/mywiki" after the above commands.

Installation into your home directory

Installation into your shell account's home directory is typically used on a host shared by many users and where you are not the root user. This usually implies that you cannot change the httpd.conf file, and also you cannot copy files into the machine's cgi-bin and htdocs directories. For this situation, Apache includes the UserDir directive, which maps all URLs that start with "/~username" to a directory in your home directory, where you have write permissions and thus can install MoinMoin.

Making sure /~username URLs work

This kind of setup can only work if your webmaster has configured the host's Apache server so that the UserDir mechanism works. Here's how to check for this:

jh@localhost:~ > ls -ld public_html
drwxr-xr-x   2 jh       users          35 Jan 31 00:29 public_html

If this does not show a listing like above, then you might need to create the public_htmldirectory. Note that this directory must be readable (r-x) by the web server.

jh@localhost:~ > lynx -error_file=/dev/stderr -dump http://localhost/~jh/ >/dev/null
URL=http://localhost/~jh/ (GET)
STATUS=HTTP/1.1 200 OK

You see here that we get a "200 OK" status response, which means that you can access your public_html area. If it does not work, you will probably get a "403 Forbidden" or a "404 Not Found" response. The first one normally indicates that you need to fix the permissions of your home directory (~) or your ~/public_html. But we also need to be able to execute CGI scripts, so we test that, too.

jh@localhost:~ > `'''`cat >~/public_html/test.cgi
#!/bin/sh
echo Content-Type: text/plain
echo
echo IT WORKS
<CTRL-D>
jh@localhost:~ > chmod a+rx ~/public_html/test.cgi
jh@localhost:~ > lynx -dump http://localhost/~jh/test.cgi
IT WORKS

If you see anything else than "IT WORKS", then you are not allowed to execute CGI scripts. How you get that to work is not in the scope of this description, ask your webmaster!

A working Python installation is also assumed.

jh@localhost:~ > python -V
Python 2.3

The command line examples show your input after the prompt (jh@localhost:~ >). The examples use "jh" as the user's name, which means you have to replace your own one whereever "jh" appears. The same is true for version numbers (1.1) and download URLs.

Doing the basic installation

The following commands will fetch and install a moin tarball. Use an appropriate URL to the version you want to install.

mkdir ~/tmp
cd ~/tmp
wget http://moin.sf.net/files/moin-1.1.tar.gz
tar xfz moin-1.1.tar.gz
cd moin-1.1
python setup.py --quiet install --home=$HOME --record=install.log

This will install the MoinMoin software into the directories "~/lib/python/MoinMoin", "~/bin", and "~/share/moin". You'll find a detailed file list in "install.log".

Setting up a wiki instance

The next step is to create a copy of the wiki data and the config file.

mkdir ~/wiki
cd ~/wiki
cp ~/share/moin/cgi-bin/moin_config.py .
cp -r ~/share/moin/data .
chmod -R o+rwX data
vi moin_config.py

The last command starts the editor, you need to at least change the "data_dir" and "url_prefix" config values, as you can see in the following diff:

@@ -28,4 +28,4 @@
 interwikiname = None
-data_dir = './data/'
-url_prefix = '/wiki'
+data_dir = '/home/jh/wiki/data/'
+url_prefix = '/~jh/wiki'
 logo_url = url_prefix + '/img/moinmoin.png'

Setting up public_html and testing the installation

Now we create the public part of the wiki, which is directly accessible by the web browser.

cd ~/public_html
cp -r ~/share/moin/htdocs wiki
cp ~/share/moin/cgi-bin/*.cgi .
chmod a+rx *.cgi

To be able to execute the CGI script in your home directory, you need to extend Python's path within that script, and possibly adapt the bang path (that is the first line of the script). So, change "moin.cgi" similarly to this diff:

@@ -1,2 +1,2 @@
-#! /usr/bin/env python
+#! /usr/local/bin/python2.3

@@ -11,4 +11,4 @@

-#import sys
-#sys.path.append('/usr/local/home/USERNAME/lib/python')
+import sys
+sys.path.extend(['/home/jh/wiki', '/home/jh/lib/python'])

Finally, you can test your wiki installation by running the MoinMoin CGI Diagnosis:

lynx -dump http://localhost/~jh/moin.cgi?test

And now, your wiki should work and is available at the URL "http://localhost/~jh/moin.cgi". Conclude your tests by editing and saving the FrontPage and checking out RecentChanges, which should reflect that edit.