Added usage on schema statements to apply grants script

shared/bcts_access_management/bcts_acces_apply_grants.py

@@ -40,7 +40,14 @@ def apply_grants():
     all_statements = []
     for _, row in df.iterrows():
         all_statements.extend(generate_grant_statements(row))
-        # Execute the grant statements in PostgreSQL
+
+    # Execute the grant statements in PostgreSQL
+    schema_roles_list = list(set([(x.split(' ON ')[1].split('.')[0], x.split(' TO ')[1].split(';')[0]) for x in all_statements]))
+    usage_statements = []
+    for (schema, role) in schema_roles_list:
+        usage_statement = f"GRANT USAGE ON SCHEMA {schema} TO {role};"
+        usage_statements.append(usage_statement)
+    all_statements.extend(usage_statements)
     with engine.begin() as connection:
         for statement in all_statements:
             logging.info(statement)