Add support for image_format/disk_fomats configuration

This is useful to avoid callers use glance::config for the sole
reason of configuring the allowed disk_formats, which can be
customized to filter out values when using particular backends,
like RBD, which perform suboptimally with certain image formats.

Change-Id: I0f343321d43efa5e4a4274f01a4592a8fcd92417

manifests/api.pp

@@ -75,6 +75,10 @@
 #   (optional) If set, use this value for max_overflow with sqlalchemy.
 #   Defaults to undef.
 #
+# [*disk_formats*]
+#   (optional) (Array) List of allowed values for an image disk_format attribute.
+#   Defaults to $::os_service_default.
+#
 # [*cache_prefetcher_interval*]
 #   (optional) The interval in seconds to run periodic job 'cache_images'
 #   Defaults to $::os_service_default.
@@ -336,6 +340,7 @@ class glance::api(
   $database_max_retries                 = undef,
   $database_retry_interval              = undef,
   $database_max_overflow                = undef,
+  $disk_formats                         = $::os_service_default,
   $cache_prefetcher_interval            = $::os_service_default,
   $image_cache_max_size                 = $::os_service_default,
   $image_cache_stall_time               = $::os_service_default,
@@ -550,6 +555,16 @@ enabled_backends instead.')
     'glance_store/filesystem_store_file_perm':     value => $filesystem_store_file_perm;
   }
 
+  # disk_formats handling
+  if $disk_formats != $::os_service_default {
+    $disk_formats_real = join(any2array($disk_formats), ',')
+  } else {
+    $disk_formats_real = $disk_formats
+  }
+  glance_api_config {
+    'image_format/disk_formats': value => $disk_formats_real;
+  }
+
   resources { 'glance_api_config':
     purge => $purge_config,
   }

releasenotes/notes/add_disk_formats_parameter-9e83e3142f8d10f9.yaml

@@ -0,0 +1,9 @@
+---
+features:
+  - |
+    Added disk_formats option which allows configuration of
+    the image_format/disk_formats config setting; some backends
+    perform poorly with specific disk formats, for example
+    Ceph with QCOW2 images and in these scenarios it might
+    be useful to filter out of the allowed disk formats those
+    which are unwanted.

spec/classes/glance_api_spec.rb

@@ -34,6 +34,7 @@ describe 'glance::api' do
       :image_cache_stall_time         => '<SERVICE DEFAULT>',
       :image_cache_max_size           => '<SERVICE DEFAULT>',
       :cache_prefetcher_interval      => '<SERVICE DEFAULT>',
+      :disk_formats                   => '<SERVICE DEFAULT>',
       :pipeline                       => 'keystone',
       :task_time_to_live              => '<SERVICE DEFAULT>',
       :task_executor                  => '<SERVICE DEFAULT>',
@@ -188,6 +189,10 @@ describe 'glance::api' do
           is_expected.to contain_glance_api_config('DEFAULT/key_file').with_value('<SERVICE DEFAULT>')
         end
 
+        it 'is_expected.to have no disk_formats set' do
+          is_expected.to contain_glance_api_config('image_format/disk_formats').with_value('<SERVICE DEFAULT>')
+        end
+
         it 'passes purge to resource' do
           is_expected.to contain_resources('glance_api_config').with({
             :purge => false
@@ -289,6 +294,18 @@ describe 'glance::api' do
       end
     end
 
+    describe 'with disk_formats option' do
+      let :params do
+        default_params.merge({
+          :disk_formats => 'raw,iso',
+        })
+      end
+
+      context 'with disk_formats option' do
+        it { is_expected.to contain_glance_api_config('image_format/disk_formats').with_value('raw,iso') }
+      end
+    end
+
     describe 'with enabled_backends and stores by default' do
       let :params do
         default_params