cdist/doc/man/cdist.text

cdist(7)
========
Nico Schottelius <nico-cdist--@--schottelius.org>


NAME
----
cdist - Configuration distribution system


DESCRIPTION
-----------
Cdist allows you to define centrally a configurations for
all systems and apply them. Cdist generally uses the push
approach (a server pushes out the configuration to the clients),
but can also be used the pull way (see cdist-push-pull(7)).

Cdist is configured in shell syntax, which is "compiled" to an
internal configuration representation (cconfig), which again
is used to generate an executable, which is run on the client
(see cdist-language(7), cdist-design(7)).



SEE ALSO
--------
cdist-deploy-to(1), website: http://www.nico.schottelius.org/cdist/[]


COPYING
-------
Copyright \(C) 2010 Nico Schottelius. Free use of this software is
granted under the terms of the GNU General Public License version 3 (GPLv3).

--------------------------------------------------------------------------------


## How cdist works

### Exploring your system

cdist analyses the system to apply the configuration on and
selects the right backends. You can use ***cdist-explore*** to
the results of the explore functions.

### Applying the configuration

cdist looks for the configuration to apply on the local host
and applies it using ***cdist-apply***.

### Managing many hosts

Whereas ***cdist-apply*** manages one host, ***cdist-deploy***
applies the configuration on enabled hosts.

## How to use cdist?

 0. Create a host specification (/etc/cdist/hosts/**hostname**)
 0. Add functionalilty to add
 0. Run ***cdist-apply***


--------------------------------------------------------------------------------
Simple stuff done by Unix[notm]

   - DSL: Shell!
      - gives if, else and EVEN elsif for free!
      - and case
      - and and and
      - and there's no os (solaris doesn't count) without a usable /bin/sh
      - cdist defines what you can use
         - you _can_ use os specific stuff
         - but it's ugly and you shoot into your own foot
      - "manifests" (use the same name here?) will be run/sourced
         - inheritance possible via sourcing
         - cdist-lib always preloaded
      - library == functions?
   - version control via git
   - file distribution via ssh
   - authentication via ssh
   - dumb clients, similar to manifest compile in puppet
      - clients just execute commands
   - dependencies via make?
      - how to ensure sigletons / conflicting definitions?
         file { "/a":
            ensure => present,
         file { "/a":
            ensure => absent,
   - matching on explored items, not only on host name?
      - match function in host? [optional]
   - file source:
      - relative to specification
      - or absolute


--------------------------------------------------------------------------------
Implementation

   "cdist-server"
      -> called by cron?
      -> no need to reimplement scheduling
   "cdist-explore" (facter replacement)
      -> running on the client
--------------------------------------------------------------------------------
Requirements:
   It MUST be incredible easy/dumb to add new types.
      => growable default types
      
      
--------------------------------------------------------------------------------

      ## TO DOC

Before initial release, document:

   - how to add package backends
   - how to write a minimal host manifest
   - create library with all functions (and their parameters)
      - cdist_package
      - cdist_file
      - cdist_dir

   - only do necessary work
      - install packages only if not existent
      - copy file only if different

   - how to write a module
      - module function autoloading via *.sh
      - module "manifest"?
         - create functions in *.sh
         - name functions "modulename_function"
            module hellow
            function kitty
            => hellow_kitty
      - you are advised (not forced) to put files
         to a subdirectory named "files"