Have the ability to run one task once to test it

[jerri]

Is your feature request related to a problem? Please describe.

I am coming from funkload, where you basically create a script that can be also executed once to test your code. This is especially necessary when you are creating a complex user journey including e.g. login, selection of some pages, addition to basket and full checkout. As far as I see right now, I would have to start locust for any change I am doing and then executing it with one user? Maybe I didn't get it right. I would prefer to have the ability to just execute a specific task once, so I can also check any logs on the target system.

Describe the solution you'd like

I assume the easist would be to have a parameter --run-once or similar, which would run every task only once. And optimally an additional parameter --run-task that takes the name of a task to run.

Describe alternatives you've considered

As mentioned, I guess the only alternative at the moment is to run with 1 user and stop the script after some seconds.

Additional context

This request is basically about debugging posibilities for locust script, especially when they become more complex.

[cyberw]

There are a couple of options, either run a single User in the debugger (using locust-plugins): https://github.com/SvenskaSpel/locust-plugins/blob/master/examples/debug_ex.py

Or (again using locust-plugins) use -i to limit the number of task iterations to 1: https://github.com/SvenskaSpel/locust-plugins/blob/master/examples/cmd_line_examples.sh#L12

[github-actions]

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[cyberw]

Fixed in #1985, released in 2.7.0

[dylan-shipwell]

motion to reopen,
#1985 appears to offers quirky way to filter a locust run to a single locust.HttpUser case; but does not appear to limit the running of each task within that HttpUser case to a single execution, nor accept either None or a list of all HttpUser classes to run one of each task.

therefore I don't see how 1985 soles the need to test locust tasks.

i'm looking for more of an

# ...
import inspect

import locust
import locust.util.load_locustfile

# collect all classes like locust does
all_user_classes_this_file = [ i[1] for i in inspect.getmembers(sys.modules[__name__]) if inspect.isclass(i[1]) and locust.util.load_locustfile.is_user_class(i)]

# define a new run function that only schedules each task one time total
class MyOnceHttpUser(locust.HttpUser):
    def run(self): # bad & broken run implementation, do not use, lost of missing error handling
        self.on_start()
        for i in self.user.tasks:
            self.schedule_task(i)
        while self._task_queue:
            self.execute_next_task()
        self.on_stop()

# run each http task one time
for user_class in all_user_classes_this_file:
    MyOnceHttpUser.run(user_class)

while poking around, I noticed there is a SequentialHttpTask class, i didin't look at its run method but maybe it would help provide this requested battery.