Add attribute for image api workers setting

- Add an attribute for ['openstack']['image']['api']['workers']
- Adjust the template for glance-api.conf to use this attributes
- Adjust the default value to be a maximum of 8 (but this can be
  overridden)
- Adjust spec tests to set the cpu value so they converge
- Add test to confirm this value can be set
- Add test to confirm the .min[8 , sets a max of 8.
- Add README.md attribute entry

Change-Id: I8bdbd8bc8fe9af7a9ca3bbc8856d5a200ce7be7b
Closes-Bug: #1274884

README.md

@@ -110,6 +110,7 @@ Attributes for the Image service are in the ['openstack']['image'] namespace.
 * `openstack['image']['service_tenant_name']` - Tenant name used by glance when interacting with keystone - used in the API and registry paste.ini files
 * `openstack['image']['service_user']` - User name used by glance when interacting with keystone - used in the API and registry paste.ini files
 * `openstack['image']['service_role']` - User role used by glance when interacting with keystone - used in the API and registry paste.ini files
+* `openstack['image']['api']['workers']` - Set the number of glance api workers.
 * `openstack['image']['api']['show_image_direct_url']` - Allow glance to return URL referencing where data is stored on the backend. Default 'False'
 * `openstack['image']['api']['auth']['cache_dir']` - Defaults to `/var/cache/glance/api`. Directory where `auth_token` middleware writes certificates for glance-api
 * `openstack['image']['registry']['auth']['cache_dir']` - Defaults to `/var/cache/glance/registry`. Directory where `auth_token` middleware writes certificates for glance-registry

attributes/default.rb

@@ -43,6 +43,9 @@ default['openstack']['image']['service_tenant_name'] = 'service'
 default['openstack']['image']['service_user'] = 'glance'
 default['openstack']['image']['service_role'] = 'admin'
 
+# Set the number of api workers
+default['openstack']['image']['api']['workers'] = [8, node['cpu']['total'].to_i].min
+
 # Return the URL that references where the data is stored on the backend.
 default['openstack']['image']['api']['show_image_direct_url'] = 'False'
 

spec/api_spec.rb

@@ -123,6 +123,18 @@ describe 'openstack-image::api' do
           /^flavor = keystone\+cachemanagement$/)
       end
 
+      it 'has configurable api workers setting' do
+        node.set['openstack']['image']['api']['workers'] = 10
+        expect(chef_run).to render_file(file.name).with_content(
+          /^workers = 10$/)
+      end
+
+      it 'confirms default min value is set' do
+        node.set['cpu']['total'] = 10
+        expect(chef_run).to render_file(file.name).with_content(
+          /^workers = 8$/)
+      end
+
       it 'sets show_image_direct_url appropriately' do
         node.set['openstack']['image']['api']['show_image_direct_url'] = 'True'
         expect(chef_run).to render_file(file.name).with_content(

spec/client-redhat_spec.rb

@@ -8,6 +8,7 @@ describe 'openstack-image::client' do
     let(:runner) { ChefSpec::Runner.new(REDHAT_OPTS) }
     let(:node) { runner.node }
     let(:chef_run) do
+      node.set_unless['cpu']['total'] = 1
       runner.converge(described_recipe)
     end
 

spec/client_spec.rb

@@ -8,6 +8,7 @@ describe 'openstack-image::client' do
     let(:runner) { ChefSpec::Runner.new(UBUNTU_OPTS) }
     let(:node) { runner.node }
     let(:chef_run) do
+      node.set_unless['cpu']['total'] = 1
       runner.converge(described_recipe)
     end
 

spec/identity_registration_spec.rb

@@ -5,6 +5,7 @@ describe 'openstack-image::identity_registration' do
   let(:runner) { ChefSpec::Runner.new(UBUNTU_OPTS) }
   let(:node) { runner.node }
   let(:chef_run) do
+    node.set_unless['cpu']['total'] = 1
     runner.converge(described_recipe)
   end
 

spec/image_upload_spec.rb

@@ -7,6 +7,7 @@ describe 'openstack-image::image_upload' do
     let(:options) { UBUNTU_OPTS.merge(step_into: 'openstack_image_image') }
     let(:node) { runner.node }
     let(:chef_run) do
+      node.set_unless['cpu']['total'] = 1
       runner.converge(described_recipe)
     end
 

spec/registry-redhat_spec.rb

@@ -6,6 +6,7 @@ describe 'openstack-image::registry' do
     let(:runner) { ChefSpec::Runner.new(REDHAT_OPTS) }
     let(:node) { runner.node }
     let(:chef_run) do
+      node.set_unless['cpu']['total'] = 1
       runner.converge(described_recipe)
     end
 

spec/registry_spec.rb

@@ -12,6 +12,7 @@ describe 'openstack-image::registry' do
     let(:runner) { ChefSpec::Runner.new(UBUNTU_OPTS) }
     let(:node) { runner.node }
     let(:chef_run) do
+      node.set_unless['cpu']['total'] = 1
       runner.converge(described_recipe)
     end
 

templates/default/glance-api.conf.erb

@@ -26,7 +26,7 @@ backlog = 4096
 # may improve performance (especially if using SSL with
 # compression turned on). It is typically recommended to set
 # this value to the number of CPUs present on your machine.
-workers = <%= node["cpu"]["total"] %>
+workers = <%= node["openstack"]["image"]["api"]["workers"] %>
 
 # SQLAlchemy connection string for the reference implementation
 # registry server. Any valid SQLAlchemy connection string is fine.