finish rewrite of cdist-manifest

Signed-off-by: Nico Schottelius <nico@brief.schottelius.org>
This commit is contained in:
Nico Schottelius 2012-01-17 21:57:32 +01:00
parent c8e4d51396
commit 5e00ac702a

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@ -5,14 +5,38 @@ Nico Schottelius <nico-cdist--@--schottelius.org>
NAME
----
cdist-manifest - Using types
cdist-manifest - (Re-)Use types
DESCRIPTION
-----------
Manifests exist to define which configurations should be applied to a specific
host as well as to define which configurations should be applied within a
type. Manifests are executed locally and the resulting objects are stored in
an internal database.
Manifests are used to define which objects to create.
Objects are instances of **types**, like in object orientated programming languages.
An object is represented by the combination of
**type + slash + object name**: **__file/etc/cdist-configured** is an
object of the type ***__file*** with the name ***etc/cdist-configured***.
All available types can be found in the **conf/type/** directory,
use **ls conf/type** to get the list of available types. If you have
setup the MANPATH correctly, you can use **man cdist-reference** to access
the reference with pointers to the manpages.
Types in manifests are used like normal command line tools. Let's have a look
at an example:
--------------------------------------------------------------------------------
# Create object of type __package with the parameter state = removed
__package apache2 --state removed
# Same with the __directory type
__directory /tmp/cdist --state present
--------------------------------------------------------------------------------
These two lines create objects, which will later be used to realise the
configuration on the target host.
Manifests are executed locally as a shell script using **/bin/sh -e**.
The resulting objects are stored in an internal database.
The same object can be redefined in multiple different manifests as long as
the parameters are exactly the same.
@ -21,17 +45,19 @@ In general, manifests are used to define which types are used depending
on given conditions.
INITIAL AND TYPE MANIFESTS
--------------------------
Cdist nows about two types of manifests: The initial manifest and type
manifests. The initial manifest is used to define, which configurations
to apply to which hosts. The type manifests are used to create objects
from types. More about manifests in types can be found in cdist-type(7).
DEFINE STATE IN THE INITIAL MANIFEST
------------------------------------
The **initial manifest** is the entry point for cdist to find out, which
**objects** to configure on the selected host. Objects are instances of
**types**, like in object orientated programming languages.
An object is represented by the
type + slash + object name: ***__file/etc/cdist-configured*** is an
object of the type ***__file*** with the name ***etc/cdist-configured***.
Cdist searches for the initial manifest at **conf/manifest/init** and
executes it as a shell script using **/bin/sh -e**.
**objects** to configure on the selected host.
Cdist searches for the initial manifest at **conf/manifest/init**.
Within this initial manifest, you define, which objects should be
created on which host. To distinguish between hosts, you can use the
@ -56,15 +82,51 @@ is only created on the host ***localhost***.
As you can see, there is no magic involved, the manifest is simple shell code that
utilises cdist types. Every available type can be executed like a normal
command. Use **ls conf/type** to get a list of available types. If you have
setup the MANPATH correctly as, you can use **man cdist-reference** to access
the reference with pointers to the manpages.
command.
INITIAL VS. TYPE MANIFEST
-------------------------
MANAGING YOUR OWN CONFIGURATION
SPLITTING UP THE INITIAL MANIFEST
---------------------------------
If you want to split up your initial manifest, you can create other shell
scripts in **conf/manifest/** and include them in **conf/manifest/init**.
Cdist provides the environment variable ***__manifest*** to reference to
the directory containing the initial manifest (see cdist-reference(7)).
The following example would include every file with a **.sh** suffix:
--------------------------------------------------------------------------------
# Include *.sh
for manifest in $__manifest/*.sh; do
# And source scripts into our shell environment
. "$manifest"
done
--------------------------------------------------------------------------------
DEPENDENCIES
------------
If you want to describe that something requires something else, just
setup the variable "require" to contain the requirements. Multiple
requirements can be added white space seperated.
--------------------------------------------------------------------------------
# No dependency
__file /etc/cdist-configured
# Require above object
require="__file/etc/cdist-configured" __link /tmp/cdist-testfile \
--source /etc/cdist-configured --type symbolic
# Require two objects
require="__file/etc/cdist-configured __link/tmp/cdist-testfile" \
__file /tmp/cdist-another-testfile
--------------------------------------------------------------------------------
All objects that are created in a type manifest are automatically required
from the type that is calling them. This is called "autorequirement" in
cdist jargon.
EXAMPLES
@ -89,36 +151,11 @@ The manifest of the type "nologin" may look like this:
__file /etc/nologin --type file --source "$__type/files/default.nologin"
--------------------------------------------------------------------------------
DEPENDENCIES
------------
If you want to describe that something requires something else, just
setup the variable "require" to contain the requirements. Multiple
requirements can be added white space seperated.
--------------------------------------------------------------------------------
# No dependency
__file /etc/cdist-configured
# Require above object
require="__file/etc/cdist-configured" __link /tmp/cdist-testfile \
--source /etc/cdist-configured --type symbolic
# Require two objects
require="__file/etc/cdist-configured __link/tmp/cdist-testfile" \
__file /tmp/cdist-another-testfile
--------------------------------------------------------------------------------
If you do not specify
FIXME: autorequire
SEE ALSO
--------
- cdist-type(7)
- cdist-tutorial(7)
- cdist-type(7)
COPYING