docs rebuild

This commit is contained in:
Michael DeHaan 2012-03-08 22:50:12 -05:00
parent 1952bd0aa3
commit 2c6dd03229
16 changed files with 333 additions and 223 deletions

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@ -13,13 +13,17 @@ ansible playbooks.
:doc:`api`
Examples of using modules with the Python API
Module Idempotence
```````````````````
Nearly all modules take key=value parameters. Some modules take no parameters, and the command
module just takes arguments for the command you want to run.
All modules return JSON format data, thoug if you are using the command line or playbooks, you
don't really need to know much about that.
Most modules other than command are idempotent, meaning they will seek to avoid changes
unless a change needs to be made. When using ansible playbooks, these modules can
trigger change events. Unless otherwise noted, all modules support change hooks.
Stock modules:
command
```````
@ -31,6 +35,8 @@ Example usage::
/sbin/shutdown -t now
The given shell command will be executed on all selected nodes.
This module does not support change hooks and returns the return code from the program as well as timing information about how long the command was running for.
@ -41,12 +47,12 @@ The copy module moves a file on the local box to remote locations.
*src*::
Local absolute path to a file to copy to the remote server
Local path to a file to copy to the remote server. This can be an absolute or relative path.
*dest*::
Remote absolute path where the file should end up
Remote absolute path where the file should end up.
This module also returns md5sum information about the resultant file.
@ -56,18 +62,19 @@ facter
``````
Runs the discovery program 'facter' on the remote system, returning
JSON data that can be useful for inventory purposes.
JSON data that can be useful for inventory purposes.
Requires that 'facter' and 'ruby-json' be installed on the remote end.
This module is informative only - it takes no parameters & does not support change hooks,
nor does it make any changes on the system.
nor does it make any changes on the system. Playbooks do not actually use
this module, they use the 'setup' module behind the scenes.
git
```
Deploys software from git checkouts.
Deploys software (or files) from git checkouts.
*repo*::
@ -93,6 +100,8 @@ Requires that 'ohai' be installed on the remote end.
This module is information only - it takes no parameters & does not
support change hooks, nor does it make any changes on the system.
Playbooks should not call the ohai module, playbooks call the 'setup'
module behind the scenes instead.
ping
````
@ -100,9 +109,7 @@ ping
A trivial test module, this module always returns the integer '1' on
successful contact.
This module does not support change hooks.
This module is informative only - it takes no parameters & does not
This module does not support change hooks and is informative only - it takes no parameters & does not
support change hooks, nor does it make any changes on the system.
@ -128,18 +135,14 @@ setup
Writes a JSON file containing key/value data, for use in templating.
Call this once before using the template modules. Playbooks will
execute this module automatically as the first step in each play.
execute this module automatically as the first step in each play using
the variables section, so it is unneccessary to make explicit calls to
setup within a playbook.
If facter or ohai are installed, variables from these programs will also
be snapshotted into the JSON file for usage in templating. These variables
are prefixed with 'facter_' and 'ohai_" so it's easy to tell their source.
*metadata*
Optionally overrides the default JSON file location of /etc/ansible/setup or ~/ansible/setup
depending on what remote user has been specified.
If used, also supply the metadata parameter to the template module.
All variables are then bubbled up to the caller.
*anything*
@ -154,43 +157,43 @@ Templates a file out to a remote server. Call the setup module prior to usage.
*src*
path of a Jinja2 formatted template on the local server
path of a Jinja2 formatted template on the local server. This can be a relative
or absolute path.
*dest*
location to render the template on the remote server
*metadata*
location of a JSON file to use to supply template data. Default is /etc/ansible/setup
which is the same as the default for the setup module. Change if running as a non-root
remote user who does not have permissions on /etc/ansible.
This module also returns md5sum information about the resultant file.
user
````
This module is in plan.
yum
```
This module is in plan.
writing your own modules
Writing your own modules
````````````````````````
To write your own modules, simply follow the convention of those already available in
/usr/share/ansible. Modules must return JSON but can be written in any language.
Modules should return hashes, but hashes can be nested.
To support change hooks, modules should return hashes with a changed: True/False
element at the top level. Modules can also choose to indicate a failure scenario
by returning a top level 'failure' element with a True value, and a 'msg' element
describing the nature of the failure. Other values are up to the module.
element at the top level::
{
'changed' : True,
'something' : 42
}
Modules can also choose to indicate a failure scenario by returning a top level 'failure'
element with a True value, and a 'msg' element describing the nature of the failure.
Other return values are up to the module.
{
'failure' : True,
'msg' : "here is what happened..."
}
When shipping modules, drop them in /usr/share/ansible, or specify the module path to the
command line tool or API. It is easy to test modules by running them directly on
the command line, passing them arguments just like they would be passed with ansible.