Allow to set an "root_address" in application.yml. This is used to declare the address of this server, when using proxy.

src/main/java/eu/openaire/pdf_aggregation_statistics/util/UriBuilder.java

@@ -31,7 +31,10 @@ public class UriBuilder {
         baseUrl += sslEnabled.equals("true") ? "s" : "";
         baseUrl += "://";
 
-        if ( (ip = getPublicIP()) == null )
+        String defined_address = environment.getProperty("server.root_address");
+        if ( (defined_address != null) && !defined_address.isEmpty() )
+            ip = defined_address;
+        else if ( (ip = getPublicIP()) == null )
             ip = InetAddress.getLoopbackAddress().getHostAddress();   // Non-null.
 
         baseUrl += ip + ":" + webServerAppCtxt.getWebServer().getPort();

src/main/resources/application.yml

@@ -1,5 +1,7 @@
 server:
     port: 1882
+    # Just a custom address to be shown to the logs and allow for easier testing, when using proxy. This is not the setting to bind the server to this address.
+    root_address:
     servlet:
         context-path: /api
     shutdown: graceful