Add OIDC compatibility

OIDC authentication requires a different Docker image from the one
used for publishing repository content. This customized image
loads the OIDC module to enable the connection but also loads
other modules listed in the chart configuration by default.

Forcing the container to load these modules results in the error
"module is built-in and can't be loaded," causing the container to
stop.

It is necessary for this Helm Chart to be compatible with different
Apache2 images. Therefore, a check is added to avoid loading
modules if `OIDC_CONFIG_PRESENT` is defined.

Signed-off-by: Pablo Vigo <pvigo@collabora.com>

chart/templates/configmap-publish.yaml

@@ -10,18 +10,21 @@ data:
     Listen 80
 
     {{ .Values.publish.config.before_modules | indent 4 }}
+    <ifDefine !CUSTOM_MODULES>
     LoadModule mpm_event_module modules/mod_mpm_event.so
     LoadModule authz_core_module modules/mod_authz_core.so
     LoadModule allowmethods_module modules/mod_allowmethods.so
     LoadModule reqtimeout_module modules/mod_reqtimeout.so
     LoadModule mime_module modules/mod_mime.so
-    LoadModule log_config_module modules/mod_log_config.so
     LoadModule headers_module modules/mod_headers.so
     LoadModule proxy_module modules/mod_proxy.so
     LoadModule proxy_http_module modules/mod_proxy_http.so
-    LoadModule unixd_module modules/mod_unixd.so
     LoadModule dir_module modules/mod_dir.so
     LoadModule autoindex_module modules/mod_autoindex.so
+    LoadModule log_config_module modules/mod_log_config.so
+    LoadModule unixd_module modules/mod_unixd.so
+    </IfDefine>
+
     {{ .Values.publish.config.after_modules | indent 4 }}
 
     <IfModule unixd_module>

chart/values.yaml

@@ -28,7 +28,13 @@ publish:
     pullPolicy: IfNotPresent
     tag: 2.4
   config:
+    # Disable default modules can be set here, e.g.:
+    # before_modules: 'Define CUSTOM_MODULES' 
     before_modules: ''
+    # Specify custom modules to load can be set here, e.g.:
+    # after_modules: |
+    #   LoadModule authz_user_module modules/mod_authz_user.so
+    #   LoadModule authn_core_module modules/mod_authn_core.so
     after_modules: ''
     after_body: ''
   resources: {}