This patch allows an array of resource titles to be passed into
the ensure_resource function. Each item in the array will be
checked for existence and will be created if it doesn't already
exist.
The ensure_resource function actually calls two
other functions, create_resources and defined_with_param.
When calling Puppet functions from Ruby, you sometimes have
to load the functions manually if they have not been called
before.
This commit explicitly loads the functions that ensure_resource
depends on from within the function.
This commit adds better inline documentation
explaining how replicate resource definitions can
occur if the resource exists and does not have
matching parameters.
This commit adds 2 new functions with unit tests.
defined_with_params works similarily to puppet's defined
function, except it allows you to also specify a hash of
params. defined_with_params will return true if a resource
also exists that matches the specified type/title (just like
with defined) as well as all of the specified params.
ensure_resource is a function that basically combines defined_with_params
with create_resources to conditionally create resources only if the
specified resource (title, type, params) does not already exist.
These functions are created to serve as an alternative to using
defined as follows:
if ! defined(Package['some_package']) {
package { 'some_package': ensure => present,
}
The issue with this usage is that there is no guarentee about
what parameters were set in the previous definition of the package
that made its way into the catalog.
ensure_resource could be used instead, as:
ensure_resource('package', 'some_package', { 'ensure' => 'present' })
This will creat the package resources only if another resource does
not exist with the specified parameters.
