TableOfContents

Publishing Repositories with hgwebdir.cgi

1. Introduction

Well, we have a certain setup with subversion. I'd like to reproduce it using Mercurial.

2. Pre-requisites

The installed software is:

• A webserver that can run CGI scripts such as apache2 (apache2, apache2-common, apache2-mpm-prefork, apache2-utils) or lighttpd
  • But it is not necessary (see below)
• some version of mercurial (mine was 0.9 taken from Debian/unstable)
• python:
  • Ubuntu/Edgy comes with python 2.4
  • you will need python2.4-dev package as well
• sudo (in general, I prefer sudo to su)

3. Getting proper Mercurial

The whole point was to try pull/push over http. So the following was done (I'm a real newbie for hg, so please bear with me :)):

$ cd working-directory
$ hg clone http://selenic.com/hg/
$ cd hg
$ python setup.py build
$ sudo python setup.py install

This should work for every linux with python. But for rpm based systems it is better for administrative reasons to use it. You can find some via [BinaryPackages]. I got mine like this:

$ cd download-directory
$ wget http://repos.opensuse.org/devel:/tools:/scm/openSUSE_10.2/x86_64/mercurial-0.9.3-3.1.x86_64.rpm
$ sudo rpm -ihv mercurial-0.9.3-3.1.x86_64.rpm

4. Directory Structure

Create the necessary directories:

$ sudo mkdir -p /var/hg/repos
$ sudo chown -R www-data:www-data /var/hg

It's usually a good idea to keep special directories out of the tree served by apache, but for security reasons on openSUSE the cgi scripts only work within the document root. So for openSUSE, which uses user/group wwwrun/www instead of www-data/www-data and does not allow write acces to cgi directories for anyone but the apache user it is

$ sudo mkdir -p /srv/www/htdocs/hg/repos
$ sudo chown -R wwwrun:www /srv/www/htdocs/hg/repos
$ sudo chmod 755 /srv/www/htdocs/hg

5. Preparing the config

$ cat > /tmp/hgweb.config
[collections]
repos/ = repos/
^D
$ sudo -u www-data cp /tmp/hgweb.config /var/hg
$ rm /tmp/hgweb.config

For openSUSE, replace the sudo line above with

$ sudo -u wwwrun cp /tmp/hgweb.config /srv/www/htdocs/hg

6. Two possibilities

You can either use a separate webserver such as Apache or lighttpd, or use the webserver built into hg.

6.1. Using Apache or lighttpd with the hgwebdir.cgi script

6.1.1. Putting the right stuff in place

Put the script in place (remember, we are still in that working-directory/hg :)):

$ sudo -u www-data cp hgwebdir.cgi /var/hg
$ sudo -u www-data chmod +x /var/hg/hgwebdir.cgi 

And again, some changes for openSUSE

$ sudo -u wwwrun cp /usr/share/doc/packages/mercurial/hgwebdir.cgi /srv/www/htdocs/hg
$ sudo -u wwwrun chmod +x /srv/www/htdocs/hg/hgwebdir.cgi 

6.1.2. Configuring apache

Ok, now it's time for apache (see at the end of this paragraph for the openSUSE way of doing this).

First of all, do not really change the config of apache directly:

$ sudo mkdir /etc/apache2/hg

Create the config with the following contents (e.g by using sudo vim /etc/apache2/hg/main.conf):

ScriptAliasMatch        ^/hg(.*)        /var/hg/hgwebdir.cgi$1

<Directory /var/hg>
  Options ExecCGI FollowSymLinks

  AllowOverride None
</Directory>

This config says that we are going to serve our repositories through '<yourhost>/hg/'.

Now make it really available, by changing your favourite site in /etc/apache2/sites-enabled. For this experiment I used /etc/apache2/sites-enabled/default:

  ...
  Include /etc/apache2/hg/main.conf
</VirtualHost>

Make sure that everything is OK:

$ sudo apache2ctl configtest
Syntax is OK

Restart your web server:

$ sudo apache2ctl stop
$ sudo apache2ctl start

Check if it works by directing your browser to <yourhost>/hg/

For openSUSE, just put this in /etc/apache2/conf.d/hg.conf

ScriptAliasMatch        ^/hg(.*)        /srv/www/htdocs/hg/hgwebdir.cgi$1

<Directory /srv/www/htdocs/hg>
  Options ExecCGI FollowSymLinks

  AllowOverride None
</Directory>

and run

sudo rcapache2 reload

if this does not complain about config errors you should be done.

6.1.3. Configuring lighttpd

Ok, now it's time for lighttpd (no openSUSE specifics, because I dont use it).

You can either update the existing /etc/lighttpd/lighttpd.conf file, or create /etc/lighttpd.conf/hg.conf and include that file from lighttpd.conf.

First, you need to check if mod_rewrite and mod_cgi are enabled in the config file, and add them to server.modules if they haven't already been added:

server.modules += ( "mod_cgi" )
server.modules += ( "mod_rewrite" )

Next, configure rewrite rules that map URLs to the hgwebdir.cgi script. With the following added to your config file, URLs starting with either hg or mercurial will map to hgwebdir.cgi:

url.rewrite-once = ( 
  "^/hg([/?].*)?$" => "/hgwebdir.cgi$1",
   "^/mercurial([/?].*)?$" => "/hgwebdir.cgi$1" 
)

Then, configure a URL match that invokes hgwebdir.cgi:

$HTTP["url"] =~ "^/hgwebdir.cgi([/?].*)?$" {
             server.document-root = "/var/hg/"
             cgi.assign = ( ".cgi" => "/usr/bin/python" )
}

Make sure that everything is OK:

$ sudo lighttpd -t -f /etc/lighttpd/lighttpd.conf 
Syntax OK

Restart the web server:

$ sudo /etc/init.d/lighttpd restart

Check if it works by directing your browser to <yourhost>/hg/ or <yourhost>/mercurial/

6.2. Standalone

Simply run

sudo -u www-data hg serve --webdir-conf /var/hg/hgweb.config

and enjoy this speedy method of serving multiple repos. It should be faster than using Apache.

7. You are done

Hooray!

8. Final Bits

No openSUSE specifics here. You should know the differences by now (apache user and doc path).

8.1. Create a new repository

$ sudo -u www-data hg init /var/hg/repos/<repository-name>

8.2. Provide more information about it

Add the following to the /var/hg/repos/<repository-name>/.hg/hgrc file:

[web]
contact = Bilbo Baggins       # Whom to contact, plain text,
                              # no fancy stuff
description = My precious!    # Nice description what this is about,
                              # you can include HTML (like <a>)

8.3. Allow pushing to the repository

By default, nobody is allowed pushing.

To allow pushing to everybody, add the following line to the /var/hg/repos/<repository-name>/.hg/hgrc file:

[web]
allow_push = *

To allow only selected users to push changes, add the following line to the /var/hg/repos/<repository-name>/.hg/hgrc file:

[web]
allow_push = frodo, sam

These are virtual users (for instance, as defined using a .htpasswd file), and not real system users.

8.4. Deny pushing to the repository

Most likely you will want to use it together with allow_push = *. If you want allow pushing to everybody, but a selected list of people, add the following line to the /var/hg/repos/<repository-name>/.hg/hgrc file:

[web]
deny_push = saruman

8.5. Allow pushing only over a non-secure channel

(I still need to check how it works )

By default, pushes are allowed only over https. If you are certain and do not want to enforce https for pushes, add the following line to the /var/hg/repos/<repository-name>/.hg/hgrc file:

[web]
push_ssl = false

8.6. Customize the look

Add the following to the /var/hg/repos/<repository-name>/.hg/hgrc file:

[web]
style = gitweb              # looks cleaner from my point of
                            # view :)
allow_archive = gz zip bz2  # If you think people should be able
                            # to download snapshots as .tar.gz,
                            # .zip, .tar.bz2 respectively

9. Disclaimer

Well, it works (worked) for me. Please do not hesitate to update this page to include small bits I've forgotten or just plainly am not aware of.