diff --git a/src/recommendationservice/Dockerfile b/src/recommendationservice/Dockerfile
index b5c34e0..0491e6f 100644
--- a/src/recommendationservice/Dockerfile
+++ b/src/recommendationservice/Dockerfile
@@ -8,9 +8,7 @@ ADD ./*.py /home/
 WORKDIR /home
 
 # set listen port
-ENV PORT="8080"
-
-#set product catalog address
-ENV PRODUCT_CATALOG_SERVICE_ADDR="localhost:8081"
+ENV PORT "8080"
+EXPOSE 8080
 
 ENTRYPOINT python /home/recommendation_server.py
diff --git a/src/recommendationservice/recommendation_server.py b/src/recommendationservice/recommendation_server.py
index 517bad9..1ea14f5 100644
--- a/src/recommendationservice/recommendation_server.py
+++ b/src/recommendationservice/recommendation_server.py
@@ -30,7 +30,9 @@ if __name__ == "__main__":
     # get port from $PORT envar
     port = os.environ.get('PORT', "8080")
     # get product catalog service address from $PRODUCT_CATALOG_SERVICE_ADDR envar
-    catalog_addr = os.environ.get('PRODUCT_CATALOG_SERVICE_ADDR', "localhost:8081")
+    catalog_addr = os.environ.get('PRODUCT_CATALOG_SERVICE_ADDR', '')
+    if catalog_addr == "":
+        raise Exception('PRODUCT_CATALOG_SERVICE_ADDR environment not set')
 
     print("product catalog address: " + catalog_addr)
     print("listening on port: " + port)