Fixes #35870 - Ensure mod_expires is loaded

In case only minimal Apache modules are loaded then mod_expires may not
be present. The result is that assets are sent without headers that
allow browsers to cache it.

manifests/config/apache.pp

@@ -154,8 +154,12 @@
   if $suburi {
     $custom_fragment = undef
   } else {
-    # mod_env is required by configuration in _assets.conf.erb
+    # mod_env and mod_expires are required by configuration in _assets.conf.erb
     include apache::mod::env
+    # apache::mod::expires pulls in a config file we don't want, like apache::default_mods
+    # It uses ensure_resource to be compatible with both $apache::default_mods set to true and false
+    include apache
+    ensure_resource('apache::mod', 'expires')
     $custom_fragment = file('foreman/_assets.conf.erb')
   }
 

spec/classes/foreman_config_apache_spec.rb

@@ -18,6 +18,8 @@
       it { should compile.with_all_deps }
 
       it 'should include apache with modules' do
+        should contain_class('apache::mod::env')
+        should contain_apache__mod('expires')
         should contain_class('apache::mod::proxy')
         should contain_class('apache::mod::proxy_http')
         should contain_class('apache::mod::proxy_wstunnel')
@@ -79,6 +81,26 @@
         should_not contain_apache__vhost('foreman-ssl')
       end
 
+      describe 'with $apache::default_mods set to false' do
+        let(:pre_condition) do
+          <<~PUPPET
+          class { 'apache':
+            default_mods => false,
+          }
+          PUPPET
+        end
+
+        it { should compile.with_all_deps }
+        it 'includes apache modules' do
+          should contain_class('apache::mod::env')
+          should contain_apache__mod('expires')
+          should contain_class('apache::mod::proxy')
+          should contain_class('apache::mod::proxy_http')
+          should contain_class('apache::mod::proxy_wstunnel')
+          should contain_class('apache::mod::rewrite')
+        end
+      end
+
       describe 'with keycloak' do
         let(:params) { super().merge(keycloak: true) }