docker: adds empty default for CUTOUT URL docker param and updates README

README.md

@@ -38,8 +38,8 @@ Configuration parameters are set by these docker environment variables:
 | **DB_USERNAME** | DB user which has access to ObsTAP |
 | **DB_PASSWORD** | and user's password |
 | *optional:* |  |
-| **CUTOUT_SERVICE_URL** | URL in Service Descriptor of the VOTable response |
-| **DISCOVERY_CONTEXT_ROOT** | root of the end-points |
+| **CUTOUT_SERVICE_URL** | URL in Service Descriptor of the VOTable response (default: <empty>)|
+| **DISCOVERY_CONTEXT_ROOT** | root of the end-points (default: siav2) |
 
 
 ## vlkb-obscore

docker/start-siav2.sh

@@ -7,6 +7,7 @@ date
 env
 
 # set optional
+CUTOUT_SERVICE_URL=${CUTOUT_SERVICE_URL:-""}
 DISCOVERY_CONTEXT_ROOT=${DISCOVERY_CONTEXT_ROOT:-siav2}
 DBG_LEVEL=${DEBUG_LEVEL:-CONFIG}