diff options
Diffstat (limited to 'doc/server/plugins/generators/tcheetah.txt')
| -rw-r--r-- | doc/server/plugins/generators/tcheetah.txt | 197 |
1 files changed, 0 insertions, 197 deletions
diff --git a/doc/server/plugins/generators/tcheetah.txt b/doc/server/plugins/generators/tcheetah.txt deleted file mode 100644 index ab147ce56..000000000 --- a/doc/server/plugins/generators/tcheetah.txt +++ /dev/null @@ -1,197 +0,0 @@ -.. -*- mode: rst -*- - -.. _server-plugins-generators-tcheetah: - -======== -TCheetah -======== - -.. warning:: - - TCheetah is deprecated. You should instead use - :ref:`server-plugins-generators-cfg-cheetah` in the Cfg plugin. - -This document reflects the ``TCheetah`` plugin. - -The ``TCheetah`` plugin allows you to use the `cheetah templating system -<http://www.cheetahtemplate.org/>`_ to create files, instead of the -various diff-based methods offered by the ``Cfg`` plugin. It also allows -you to include the results of probes executed on the client in the -created files. - -To begin, you will need to download and install the Cheetah templating -engine from http://www.cheetahtemplate.org/. Once it is installed, -you can enable it by adding ``TCheetah`` to the ``plugins`` line in -``/etc/bcfg2.conf`` on your Bcfg server. For example:: - - plugins = Base,Bundler,Cfg,...,TCheetah - -The ``TCheetah`` plugin makes use of a ``Cfg``-like directory structure -located in in a ``TCheetah`` subdirectory of your repository, usually -``/var/lib/bcfg2/TCheetah``. Each file has a directory containing two -files, ``template`` and ``info``. The template is a standard Cheetah -template with two additions: - -* `self.metadata` is the client's :ref:`metadata <server-plugins-grouping-metadata-clientmetadata>` -* `self.metadata.Properties.xdata` is an xml document of unstructured data - -The ``info`` file is formatted like ``:info`` files from Cfg. - -Mostly, people will want to use client metadata. - -File permissions -================ - -File permissions for entries handled by TCheetah are controlled via the -use of :ref:`server-info` files. Note that you **cannot** use both a -Permissions entry and a Path entry to handle the same file. - -self.metadata variables -======================= - -self.metadata is an instance of the class ClientMetadata and documented -:ref:`here <server-plugins-grouping-metadata-clientmetadata>`. - -self.metadata.Properties.xdata -============================== - -.. note:: - - If you want to use Properties, you will need to enable the - :ref:`server-plugins-connectors-properties` plugin in - ``/etc/bcfg2.conf``. - -Properties.xdata is a python `ElementTree <http://codespeak.net/lxml/>`_ -object, loaded from the data in ``/var/lib/bcfg2/Properties/<properties -file>.xml``. That file should have a ``Properties`` node at its root. - -Example ``Properties/example.xml``: - -.. code-block:: xml - - <Properties> - <host> - <www.example.com> - <rootdev>/dev/sda</rootdev> - </www.example.com> - </host> - </Properties> - -You may use any of the ElementTree methods to access data in your -template. Several examples follow, each producing an identical result -on the host 'www.example.com':: - - $self.metadata.Properties['example.xml'].xdata.find('host').find('www.example.com').find('rootdev').text - $self.metadata.Properties['example.xml'].xdata.find('host').find($self.metadata.hostname).find('rootdev').text - ${self.metadata.Properties['example.xml'].xdata.xpath('host/www.example.com/rootdev')[0].text} - ${self.metadata.Properties['example.xml'].xdata.xpath('host/' + self.metadata.hostname + '/rootdev')[0].text} - #set $path = 'host/' + $self.metadata.hostname + '/rootdev' - ${self.metadata.Properties['example.xml'].xdata.xpath($path)[0].text} - ${self.metadata.Properties['example.xml'].xdata.xpath(path)[0].text} - -Other Variables -=============== - -* **Template.searchList(self)[1]['path']** is the Path name specified in a Bundle -* **Template.searchList(self)[1]['source_path']** is the path to the TCheetah template on the Bcfg2 server - -Simple Example -============== - -TCheetah works similar to Cfg in that you define all literal information -about a particular file in a directory rooted at TGenshi/path_to_file. -The actual file contents are placed in a file named `template` in that -directory. Below is a simple example a file ``/foo``. - -``/var/lib/bcfg2/TCheetah/foo/template`` - -.. code-block:: none - - > buildfile /foo <clientname> - Hostname is $self.metadata.hostname - Filename is $Template.searchList(self)[1]['path'] - Template is $Template.searchList(self)[1]['source_path'] - Groups: - #for $group in $self.metadata.groups: - * $group - #end for - Categories: - #for $category in $self.metadata.categories: - * $category -- $self.metadata.categories[$category] - #end for - - Probes: - #for $probe in $self.metadata.Probes: - * $probe -- $self.metadata.Probes[$probe] - #end for - -``/var/lib/bcfg2/TCheetah/foo/info`` - -.. code-block:: none - - mode: 624 - -Output ------- - -The following output can be generated with bcfg2-info. Note that probe -information is not persistent, hence, it only works when clients directly -query the server. For this reason, bcfg2-info output doesn't reflect -current client probe state. - -.. code-block:: xml - - <Path type="file" name="/foo" owner="root" mode="0624" group="root"> - Hostname is topaz.mcs.anl.gov - Filename is /foo - Template is /var/lib/bcfg2/TCheetah/foo/template - Groups: - * desktop - * mcs-base - * ypbound - * workstation - * xserver - * debian-sarge - * debian - * a - Categories: - * test -- a - - Probes: - </Path> - -Example: Replace the crontab plugin -=================================== - -In many cases you can use the TCheetah plugin to avoid writing custom -plugins in Python. This example randomizes the time of cron.daily -execution with a stable result. Cron.daily is run at a consistent, -randomized time between midnight and 7am.:: - - #import random - #silent random.seed($self.metadata.hostname) - - # /etc/crontab: system-wide crontab - # Unlike any other crontab you don't have to run the `crontab` - # command to install the new version when you edit this file. - # This file also has a username field, that none of the other crontabs do. - - SHELL=/bin/sh - PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin://bin - - # m h dom mon dow user command - 17 * * * * root run-parts --report /etc/cron.hourly - $random.randrange(0,59) $random.randrange(0,6) * * * root test -x /usr/sbin/anacron || run-parts --report /etc/cron.daily - 47 6 * * 7 root test -x /usr/sbin/anacron || run-parts --report /etc/cron.weekly - 52 6 1 * * root test -x /usr/sbin/anacron || run-parts --report /etc/cron.monthly. - -.. note:: Comments and Cheetah - As Cheetah processes your templates it will consider hash "#" style - comments to be actual comments in the template and will strip them - from the final config file. If you would like to preserve the comment - in the final config file you need to escape the hash character '\#' - which will tell Cheetah (and Python) that you do in fact want the - comment to appear in the final config file.:: - - # This is a comment in my template which will be stripped when it's processed through Cheetah - \# This comment will appear in the generated config file. |