diff --git a/docker/nginx/conf.d/include/cors b/docker/nginx/conf.d/include/cors
index add176d2..fd8e1220 100644
--- a/docker/nginx/conf.d/include/cors
+++ b/docker/nginx/conf.d/include/cors
@@ -11,4 +11,4 @@ if ($request_method = 'OPTIONS') {
 more_set_headers 'Access-Control-Allow-Origin: *';
 more_set_headers 'Access-Control-Allow-Methods: GET, POST, OPTIONS, PUT, DELETE';
 more_set_headers 'Access-Control-Allow-Headers: DNT,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Range';
-more_set_headers 'Access-Control-Expose-Headers: Content-Length,Content-Range,Skynet-File-Metadata,Skynet-Skylink';
+more_set_headers 'Access-Control-Expose-Headers: Content-Length,Content-Range,Skynet-File-Metadata,Skynet-Skylink,Skynet-Portal-Api';
diff --git a/docker/nginx/nginx.conf b/docker/nginx/nginx.conf
index 4cff1f70..3a5b885e 100644
--- a/docker/nginx/nginx.conf
+++ b/docker/nginx/nginx.conf
@@ -25,6 +25,7 @@ worker_processes  1;
 
 #pid        logs/nginx.pid;
 
+env SKYNET_PORTAL_API; # declare env variable to use it in config
 
 events {
     worker_connections  1024;
@@ -62,5 +63,8 @@ http {
 
     #gzip  on;
 
+    # include skynet-portal-api header on every request
+    header_filter_by_lua 'ngx.header["Skynet-Portal-Api"] = os.getenv("SKYNET_PORTAL_API")';
+
     include /etc/nginx/conf.d/*.conf;
 }