TMSS-761: trying to comply with weird XML schema definitions

lib/siplib.py

@@ -1488,16 +1488,17 @@ class Sip(object):
             raise Exception("This SIP does not describe a correlated dataproduct. No subarray pointing available.")
 
     # this will also validate the document so far
-    def get_prettyxml(self, schema_location:str = None):
+    def get_prettyxml(self):
         try:
             dom = self.__sip.toDOM()
             dom.documentElement.setAttribute("xmlns:xsi", "http://www.w3.org/2001/XMLSchema-instance")
-            if schema_location is None:
-                # this is/was the default schema location, even though we never hosted the xsd at the astron server
-                # That makes xmllint fail to validate (because the schema obviously can't be found)
-                schema_location = "http://www.astron.nl/SIP-Lofar LTA-SIP-2.7.2.xsd"
+
+            # XML schema's have a weird way of using namespaces and locations....
+            # search the internet, everybody thinks it's too complicated,
+            # and that it does not make sense that the schema_location/namespace should be URI's which can be URL's but are not mandated to actually serve the schema at that URL...
+            schema_location = "http://www.astron.nl/SIP-Lofar"
             dom.documentElement.setAttribute('xsi:schemaLocation', schema_location)
-            dom.documentElement.setAttribute('xmlns:sip', schema_location.split(' ')[0])
+            dom.documentElement.setAttribute('xmlns:sip', schema_location)
             return dom.toprettyxml()
         except pyxb.ValidationError as err:
             logger.error(err.details())