Gitit is a wiki program written in Haskell. It uses Happstack for the web server and pandoc for markup processing. Pages and uploaded files are stored in a git, darcs, or mercurial repository and may be modified either by using the VCS's command-line tools or through the wiki's web interface. By default, pandoc's extended version of markdown is used as a markup language, but reStructuredText, LaTeX, HTML, DocBook, or Emacs Org-mode markup can also be used. Gitit can be configured to display TeX math (using texmath) and highlighted source code (using highlighting-kate).
Other features include
-
plugins: dynamically loaded page transformations written in Haskell (see "Network.Gitit.Interface")
-
categories
-
TeX math
-
syntax highlighting of source code files and code snippets (using highlighting-kate)
-
caching
-
Atom feeds (site-wide and per-page)
-
a library, "Network.Gitit", that makes it simple to include a gitit wiki in any happstack application
The most reliable way to install gitit from source is to get the stack tool. Then clone the gitit repository and use stack to install:
git clone https://github.com/jgm/gitit
cd gitit
stack install
Alternatively, instead of using stack, you can get the Haskell Platform and do the following:
cabal update
cabal install gitit
This will install the latest released version of gitit. To install a version of gitit checked out from the repository, change to the gitit directory and type:
cabal install
The cabal tool will automatically install all of the required haskell
libraries. If all goes well, by the end of this process, the latest
release of gitit will be installed in your local .cabal directory. You
can check this by trying:
gitit --version
If that doesn't work, check to see that gitit is in your local
cabal-install executable directory (usually ~/.cabal/bin). And make
sure ~/.cabal/bin is in your system path.
To run gitit, you'll need git in your system path. (Or darcs or
hg, if you're using darcs or mercurial to store the wiki data.)
Gitit assumes that the page files (stored in the git repository) are
encoded as UTF-8. Even page names may be UTF-8 if the file system
supports this. So you should make sure that you are using a UTF-8 locale
when running gitit. (To check this, type locale.)
Switch to the directory where you want to run gitit. This should be a
directory where you have write access, since three directories, static,
templates, and wikidata, and two files, gitit-users and gitit.log,
will be created here. To start gitit, just type:
gitit
If all goes well, gitit will do the following:
- Create a git repository,
wikidata, and add a default front page. - Create a
staticdirectory containing files to be treated as static files by gitit. - Create a
templatesdirectory containing HStringTemplate templates for wiki pages. - Start a web server on port 5001.
Check that it worked: open a web browser and go to http://localhost:5001.
You can control the port that gitit runs on using the -p option:
gitit -p 4000 will start gitit on port 4000. Additional runtime
options are described by gitit -h.
For instructions on editing pages and creating links, see the "Help" page.
Gitit interprets links with empty URLs as wikilinks. Thus, in markdown
pages, [Front Page]() creates an internal wikilink to the page Front Page. In reStructuredText pages, `Front Page <>`_ has the same
effect.
If you want to link to a directory listing for a subdirectory, use a
trailing slash: [foo/bar/]() creates a link to the directory for
foo/bar.
Pages may optionally begin with a metadata block. Here is an example:
---
format: latex+lhs
categories: haskell math
toc: no
title: Haskell and
Category Theory
...
\section{Why Category Theory?}
The metadata block consists of a list of key-value pairs, each on a
separate line. If needed, the value can be continued on one or more
additional line, which must begin with a space. (This is illustrated by
the "title" example above.) The metadata block must begin with a line
--- and end with a line ... optionally followed by one or more blank
lines. (The metadata block is a valid YAML document, though not all YAML
documents will be valid metadata blocks.)
Currently the following keys are supported:
format
: Overrides the default page type as specified in the configuration file.
Possible values are markdown, rst, latex, html, markdown+lhs,
rst+lhs, latex+lhs. (Capitalization is ignored, so you can also
use LaTeX, HTML, etc.) The +lhs variants indicate that the page
is to be interpreted as literate Haskell. If this field is missing,
the default page type will be used.
categories : A space or comma separated list of categories to which the page belongs.
toc
: Overrides default setting for table-of-contents in the configuration file.
Values can be yes, no, true, or false (capitalization is ignored).
title : By default the displayed page title is the page name. This metadata element overrides that default.
If gitit was compiled against a version of pandoc that has highlighting support (see above), you can get highlighted source code by using delimited code blocks:
~~~ {.haskell .numberLines}
qsort [] = []
qsort (x:xs) = qsort (filter (< x) xs) ++ [x] ++
qsort (filter (>= x) xs)
~~~
To see what languages your pandoc was compiled to highlight:
pandoc -v
Use the option -f [filename] to specify a configuration file:
gitit -f my.conf
The configuration can be split between several files:
gitit -f my.conf -f additional.conf
One use case is to keep sensible part of the configuration outside of a SCM (oauth client secret for example).
If this option is not used, gitit will use a default configuration. To get a copy of the default configuration file, which you can customize, just type:
gitit --print-default-config > my.conf
The default configuration file is documented with comments throughout.
On receiving a request, gitit always looks first in the static
directory (or in whatever directory is specified for static-dir in
the configuration file). If a file corresponding to the request is
found there, it is served immediately. If the file is not found in
static, gitit next looks in the static subdirectory of gitit's data
file ($CABALDIR/share/gitit-x.y.z/data). This is where default css,
images, and javascripts are stored. If the file is not found there
either, gitit treats the request as a request for a wiki page or wiki
command.
So, you can throw anything you want to be served statically (for
example, a robots.txt file or favicon.ico) in the static
directory. You can override any of gitit's default css, javascript, or
image files by putting a file with the same relative path in static.
Note that gitit has a default robots.txt file that excludes all
URLs beginning with /_.
Note: if you set static-dir to be a subdirectory of repository-path,
and then add the files in the static directory to your repository, you
can ensure that others who clone your wiki repository get these files
as well. It will not be possible to modify these files using the web
interface, but they will be modifiable via git.
By default, gitit will store wiki pages in a git repository in the
wikidata directory. If you'd prefer to use darcs instead of git,
you need to add the following field to the configuration file:
repository-type: Darcs
If you'd prefer to use mercurial, add:
repository-type: Mercurial
This program may be called "darcsit" instead of "gitit" when a darcs backend is used.
Note: we recommend that you use gitit/darcsit with darcs version 2.3.0 or greater. If you must use an older version of darcs, then you need to compile the filestore library without the (default) maxcount flag, before (re)installing gitit:
cabal install --reinstall filestore -f-maxcount
cabal install --reinstall gitit
Otherwise you will get an error when you attempt to access your repository.
To change the look of the wiki, you can modify custom.css in
static/css.
To change the look of printed pages, copy gitit's default print.css
to static/css and modify it.
The logo picture can be changed by copying a new PNG file to
static/img/logo.png. The default logo is 138x155 pixels.
To change the footer, modify templates/footer.st.
For more radical changes, you can override any of the default
templates in $CABALDIR/share/gitit-x.y.z/data/templates by copying
the file into templates, modifying it, and restarting gitit. The
page.st template is the master template; it includes the others.
Interpolated variables are surrounded by $s, so literal $ must
be backslash-escaped.
To write math on a markdown-formatted wiki page, just enclose it in dollar signs, as in LaTeX:
Here is a formula: $\frac{1}{\sqrt{c^2}}$
You can write display math by enclosing it in double dollar signs:
$$\frac{1}{\sqrt{c^2}}$$
Gitit can display TeX math in three different ways, depending on the
setting of math in the configuration file:
-
mathjax(default): Math will be rendered using the MathJax javascript. -
mathml: Math will be converted to MathML using texmath. This method works with IE+mathplayer, Firefox, and Opera, but not Safari. -
raw: Math will be rendered as raw LaTeX codes.
If you want to limit account creation on your wiki, the easiest way to do this
is to provide an access-question in your configuration file. (See the commented
default configuration file.) Nobody will be able to create an account without
knowing the answer to the access question.
Another approach is to use HTTP authentication. (See the config file comments on
authentication-method.)
If you want to authenticate the user from github through oauth2, you need to register your app with github to obtain a OAuth client secret and add the following section to your configuration file:
[Github]
oauthclientid: 01239456789abcdef012
oauthclientsecret: 01239456789abcdef01239456789abcdef012394
oauthcallback: http://mysite/_githubCallback
oauthoauthorizeendpoint: https://github.com/login/oauth/authorize
oauthaccesstokenendpoint: https://github.com/login/oauth/access_token
## Uncomment if you are checking membership against an organization and change
## gitit-testorg to this organization:
# github-org: gitit-testorg
The github authentication uses the scope user:email. This way, gitit gets the
email of the user, and the commit can be assigned to the right author if the
wikidata repository is pushed to github. Additionally, it uses read:org if you
uses the option github-org to check membership against an organization.
To push your repository to gitub after each commit, you can add the file
post-commit with the content below in the .git/hooks directory of your
wikidata repository.
#!/bin/sh
git push origin master 2>> logit
Plugins are small Haskell programs that transform a wiki page after it
has been converted from Markdown or another source format. See the example
plugins in the plugins directory. To enable a plugin, include the path to the
plugin (or its module name) in the plugins field of the configuration file.
(If the plugin name starts with Network.Gitit.Plugin., gitit will assume that
the plugin is an installed module and will not look for a source file.)
Plugin support is enabled by default. However, plugin support makes
the gitit executable considerably larger and more memory-hungry.
If you don't need plugins, you may want to compile gitit without plugin
support. To do this, unset the plugins Cabal flag:
cabal install --reinstall gitit -f-plugins
Note also that if you compile gitit for executable profiling, attempts to load plugins will result in "internal error: PAP object entered!"
All the pages and uploaded files are stored in a git repository. By
default, this lives in the wikidata directory (though this can be
changed through configuration options). So you can interact with the
wiki using git command line tools:
git clone ssh://my.server.edu/path/of/wiki/wikidata
cd wikidata
vim Front\ Page.page # edit the page
git commit -m "Added message about wiki etiquette" Front\ Page.page
git push
If you now look at the Front Page on the wiki, you should see your changes
reflected there. Note that the pages all have the extension .page.
If you are using the darcs or mercurial backend, the commands will be slightly different. See the documentation for your VCS for details.
By default, gitit does not cache content. If your wiki receives a lot of
traffic or contains pages that are slow to render, you may want to activate
caching. To do this, set the configuration option use-cache to yes.
By default, rendered pages, and highlighted source files
will be cached in the cache directory. (Another directory can be
specified by setting the cache-dir configuration option.)
Cached pages are updated when pages are modified using the web
interface. They are not updated when pages are modified directly through
git or darcs. However, the cache can be refreshed manually by pressing
Ctrl-R when viewing a page, or by sending an HTTP GET or POST request to
/_expire/path/to/page, where path/to/page is the name of the page to
be expired.
Users who frequently update pages using git or darcs may wish to add a
hook to the repository that makes the appropriate HTTP request to expire
pages when they are updated. To facilitate such hooks, the gitit cabal
package includes an executable expireGititCache. Assuming you are
running gitit at port 5001 on localhost, and the environment variable
CHANGED_FILES contains a list of the files that have changed, you can
expire their cached versions using
expireGititCache http://localhost:5001 $CHANGED_FILES
Or you can specify the files directly:
expireGititCache http://localhost:5001 "Front Page.page" foo/bar/baz.c
This program will return a success status (0) if the page has been successfully expired (or if it was never cached in the first place), and a failure status (> 0) otherwise.
The cache is persistent through restarts of gitit. To expire all cached
pages, simply remove the cache directory.
By default, GHC's runtime will repeatedly attempt to collect garbage when an executable like Gitit is idle. This means that gitit will, after the first page request, never use 0% CPU time and sleep, but will use ~1%. This can be bad for battery life, among other things.
To fix this, one can disable the idle-time GC with the runtime flag
-I0:
gitit -f my.conf +RTS -I0 -RTS
Note:
To enable RTS, cabal needs to pass the compile flag -rtsopts to GHC while installing.
cabal install --reinstall gitit --ghc-options="-rtsopts"
Most users who run a public-facing gitit will want gitit to appear
at a nice URL like http://wiki.mysite.com or
http://mysite.com/wiki rather than http://mysite.com:5001.
This can be achieved using apache's mod_proxy.
Set up your DNS so that http://wiki.mysite.com maps to
your server's IP address. Make sure that the mod_proxy, mod_proxy_http and mod_rewrite modules are
loaded, and set up a virtual host with the following configuration:
<VirtualHost *>
ServerName wiki.mysite.com
DocumentRoot /var/www/
RewriteEngine On
ProxyPreserveHost On
ProxyRequests Off
<Proxy *>
Order deny,allow
Allow from all
</Proxy>
ProxyPassReverse / http://127.0.0.1:5001
RewriteRule ^(.*) http://127.0.0.1:5001$1 [P]
ErrorLog /var/log/apache2/error.log
LogLevel warn
CustomLog /var/log/apache2/access.log combined
ServerSignature On
</VirtualHost>
Reload your apache configuration and you should be all set.
Drop a file called wiki.example.com.conf into /etc/nginx/conf.d
(or where ever your distribution puts it).
server {
listen 80;
server_name wiki.example.com
location / {
proxy_pass http://127.0.0.1:5001/;
proxy_set_header X-Real-IP $remote_addr;
proxy_redirect off;
}
access_log /var/log/nginx/wiki.example.com.log main;
}
Reload your nginx config and you should be all set.
Make sure the mod_proxy, mod_headers, mod_proxy_http,
and mod_proxy_html modules are loaded. mod_proxy_html
is an external module, which can be obtained [here]
(http://apache.webthing.com/mod_proxy_html/). It rewrites URLs that
occur in web pages. Here we will use it to rewrite gitit's links so that
they all begin with /wiki/.
First, tell gitit not to compress pages, since mod_proxy_html needs
uncompressed pages to parse. You can do this by setting the gitit
configuration option
compress-responses: no
Second, modify the link in the reset-password-message in the
configuration file: instead of
http://$hostname$:$port$$resetlink$
set it to
http://$hostname$/wiki$resetlink$
Restart gitit.
Now add the following lines to the apache configuration file for the
mysite.com server:
# These commands will proxy /wiki/ to port 5001
ProxyRequests Off
<Proxy *>
Order deny,allow
Allow from all
</Proxy>
ProxyPass /wiki/ http://127.0.0.1:5001/
<Location /wiki/>
SetOutputFilter proxy-html
ProxyPassReverse /
ProxyHTMLURLMap / /wiki/
ProxyHTMLDocType "<!DOCTYPE html PUBLIC '-//W3C//DTD XHTML 1.0 Strict//EN' 'http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd'>" XHTML
RequestHeader unset Accept-Encoding
</Location>
Reload your apache configuration and you should be set.
For further information on the use of mod_proxy_http to rewrite URLs,
see the mod_proxy_html guide.
By importing the module Network.Gitit, you can include a gitit wiki
(or several of them) in another happstack application. There are some
simple examples in the haddock documentation for Network.Gitit.
Bugs may be reported (and feature requests filed) at https://github.com/jgm/gitit/issues.
There is a mailing list for users and developers at http://groups.google.com/group/gitit-discuss.
A number of people have contributed patches:
- Gwern Branwen helped to optimize gitit and wrote the InterwikiPlugin. He also helped with the Feed module.
- Simon Michael contributed the patch adding RST support.
- Henry Laxen added support for password resets and helped with the apache proxy instructions.
- Anton van Straaten made the process of page generation more modular by adding Gitit.ContentTransformer.
- Robin Green helped improve the plugin API and interface, and fixed a security problem with the reset password code.
- Thomas Hartman helped improve the index page, making directory browsing persistent, and fixed a bug in template recompilation.
- Justin Bogner improved the appearance of the preview button.
- Kohei Ozaki contributed the ImgTexPlugin.
- Michael Terepeta improved validation of change descriptions.
- mightybyte suggested making gitit available as a library, and contributed a patch to ifLoggedIn that was needed to make gitit usable with a custom authentication scheme.
I am especially grateful to the darcs team for using darcsit for their public-facing wiki. This has helped immensely in identifying issues and improving performance.
Gitit's default visual layout is shamelessly borrowed from Wikipedia.
The stylesheets are influenced by Wikipedia's stylesheets and by the
bluetrip CSS framework (see BLUETRIP-LICENSE). Some of the icons in
img/icons come from bluetrip as well.