PYTHONUNBUFFERED=1 helped, but the main problem was not being able to connect to mariadb...

swagger_server/__main__.py

@@ -4,19 +4,13 @@ import connexion
 
 from swagger_server import encoder
 
-print("We in main file")
-
 def main():
-    print("Starting app1")
     app = connexion.App(__name__, specification_dir='./swagger/')
-    print("Starting app2")
     app.app.json_encoder = encoder.JSONEncoder
-    print("Starting app3")
     app.add_api('swagger.yaml', arguments={'title': 'OpenAPI definition'}, pythonic_params=True)
     print("Starting app4")
     app.run(port=8080)
 
 
 if __name__ == '__main__':
-    print("Starting main function")
     main()

swagger_server/db_utils.py

@@ -11,20 +11,17 @@ database_info = {
     'password': config('MDB_PASSWORD')
 }
 
-print("connecting to mariadb")
+cur = None
 
 # Connect to MariaDB Platform
 try:
     conn = mariadb.connect(**database_info)
+    # Get cursor
+    cur = conn.cursor()
 except mariadb.Error as e:
     print(f"Error connecting to MariaDB Platform: {e}")
-    sys.exit(1)
+    # sys.exit(1)
 
-print("connected to mariadb")
-
-
-# Get Cursor
-cur = conn.cursor()
 
 # class BaseModel(Model):
 #     class Meta: