From ba789deac588dea83a129544f8aa00813db30bf0 Mon Sep 17 00:00:00 2001
From: Dan Bode <dan@puppetlabs.com>
Date: Tue, 7 Aug 2012 20:48:54 -0700
Subject: Add function ensure_resource and defined_with_params

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.
---
 lib/puppet/parser/functions/defined_with_params.rb | 33 ++++++++++++++++++++++
 1 file changed, 33 insertions(+)
 create mode 100644 lib/puppet/parser/functions/defined_with_params.rb

(limited to 'lib/puppet/parser/functions/defined_with_params.rb')

diff --git a/lib/puppet/parser/functions/defined_with_params.rb b/lib/puppet/parser/functions/defined_with_params.rb
new file mode 100644
index 0000000..e09e41c
--- /dev/null
+++ b/lib/puppet/parser/functions/defined_with_params.rb
@@ -0,0 +1,33 @@
+# Test whether a given class or definition is defined
+require 'puppet/parser/functions'
+
+Puppet::Parser::Functions.newfunction(:defined_with_params,
+                                      :type => :rvalue,
+                                      :doc => <<-'ENDOFDOC'
+Takes a resource reference and an optional hash of attributes.
+
+Returns true if a resource with the specified attributes has already been added
+to the catalog, and false otherwise.
+
+    user { 'dan':
+      ensure => present,
+    }
+
+    if ! defined_with_params(User[dan], {'ensure' => 'present' }) {
+      user { 'dan': ensure => present, }
+    }
+ENDOFDOC
+) do |vals|
+  reference, params = vals
+  raise(ArgumentError, 'Must specify a reference') unless reference
+  params ||= {}
+  ret = false
+  if resource = findresource(reference.to_s)
+    matches = params.collect do |key, value|
+      resource[key] == value
+    end
+    ret = params.empty? || !matches.include?(false)
+  end
+  Puppet.debug("Resource #{reference} was not determined to be defined")
+  ret
+end
-- 
cgit v1.2.3


From fe85f467c8f8e65c9fd09acff17ac4adb80f12b8 Mon Sep 17 00:00:00 2001
From: Dan Bode <dan@puppetlabs.com>
Date: Mon, 13 Aug 2012 18:52:00 -0700
Subject: Handle undef for parameter argument

This commit adds better handling of the case where
undef is passed as the parameter value.

This works by converting '' into []
---
 lib/puppet/parser/functions/defined_with_params.rb | 4 +++-
 spec/functions/defined_with_params_spec.rb         | 1 +
 spec/functions/ensure_resource_spec.rb             | 1 +
 3 files changed, 5 insertions(+), 1 deletion(-)

(limited to 'lib/puppet/parser/functions/defined_with_params.rb')

diff --git a/lib/puppet/parser/functions/defined_with_params.rb b/lib/puppet/parser/functions/defined_with_params.rb
index e09e41c..d7df306 100644
--- a/lib/puppet/parser/functions/defined_with_params.rb
+++ b/lib/puppet/parser/functions/defined_with_params.rb
@@ -20,7 +20,9 @@ ENDOFDOC
 ) do |vals|
   reference, params = vals
   raise(ArgumentError, 'Must specify a reference') unless reference
-  params ||= {}
+  if (! params) || params == ''
+    params = {}
+  end
   ret = false
   if resource = findresource(reference.to_s)
     matches = params.collect do |key, value|
diff --git a/spec/functions/defined_with_params_spec.rb b/spec/functions/defined_with_params_spec.rb
index 21c08a0..f995b67 100644
--- a/spec/functions/defined_with_params_spec.rb
+++ b/spec/functions/defined_with_params_spec.rb
@@ -26,6 +26,7 @@ describe 'defined_with_params' do
       should run.with_params('User[dan]', {'ensure' => 'present'}).and_return(true)
       should run.with_params('User[dan]', {'ensure' => 'present', 'managehome' => false}).and_return(true)
       should run.with_params('User[dan]', {'ensure' => 'absent', 'managehome' => false}).and_return(false)
+      should run.with_params('User[dan]', '').and_return(true)
     end
   end
 end
diff --git a/spec/functions/ensure_resource_spec.rb b/spec/functions/ensure_resource_spec.rb
index e45a6d0..e03efda 100644
--- a/spec/functions/ensure_resource_spec.rb
+++ b/spec/functions/ensure_resource_spec.rb
@@ -26,6 +26,7 @@ describe 'ensure_resource' do
     it do
       # these first three should not fail
       should run.with_params('User', 'dan', {})
+      should run.with_params('User', 'dan', '')
       should run.with_params('User', 'dan', {'ensure' => 'present'})
       should run.with_params('User', 'dan', {'ensure' => 'present', 'managehome' => false})
       #  test that this fails
-- 
cgit v1.2.3