Handling Custom Parameters for a Reusable User Class

[oielbanna]

Hello!

Context

I am working on a package that contains abstract reusable user classes with common functionality in a few APIs that I would like to load test instead of rewriting the same user class in each one of those APIs since they're all in different repositories. Some user classes require custom parameters which I have defined by adding a listener and invoking the add_argument function similar to the following

@events.init_command_line_parser.add_listener
def custom_arguments(parser):
  parser.add_argument(
    "--name",
    type=str,
    default=""
  )

class SampleReusableUser(FastHttpUser):
  abstract = True

  ... 
  other functions implemented here
   

Problem

Some users require custom params, some uses dont. The problem arises when I import anything from my package, the custom params do show up on the UI even if the user I am importing does not define an event listener. I assume that is because there is no logic to control for adding the event listener described above so locust correctly adds those arguments. My question is:

• Is there another way to add custom arguments besides adding this event listener? Potentially from within the user class itself?
• If not, is there a way to prevent an event from triggering unless some specific conditions are met?
• Im happy to get any feedback or pointers on how to build a reusable user library for locust in general as well or if you can point me to a similar example. The main purpose here is to not rewrite an entire locust test in many locations 🙏

Thanks!

[cyberw]

I think the easiest way to accomplish this is by using multiple locustfiles. Then you can do something like

locust -f add_name_parameter.py,users_that_use_name.py

or

locust -f users_that_dont_use_name.py

if you want to prevent a method from being called, I’d recommend env vars, something like

if os.getenv(”USENAME”):
    @events.init_command_line_parser.add_listener
    def custom_arguments(parser):
        …

[oielbanna]

Thank you @cyberw Ill try to restructure it that way 🙏