how to init arguments in User class - locust

Question

I create a User class with some init arguments, but got TypeError as below when executed :"locust -f stress.py --headless -u 100 -r 100 -t 1m"
Traceback (most recent call last):
File "src/gevent/greenlet.py", line 906, in gevent._gevent_cgreenlet.Greenlet.run
File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/locust/runners.py", line 406, in
lambda: super(LocalRunner, self).start(user_count, spawn_rate, wait=wait)
File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/locust/runners.py", line 314, in start
self.spawn_users(user_count, spawn_rate=spawn_rate, wait=wait)
File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/locust/runners.py", line 206, in spawn_users
spawn()
File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/locust/runners.py", line 199, in spawn
new_user = user_class(self.environment)
TypeError: init() missing 4 required positional arguments: 'uid', 'room_id', 'action_uid', and 'appkey'
class JoinRoomUser(HttpUser):
wait_time = between(1, 2.5)
host = ''
def __init__(self, env, uid, room_id, action_uid, appkey):
self.env = env
self.uid = uid
self.room_id =room_id
self.action_id = action_uid
self.appkey = appkey
how to init these arguments?
the task in locust script as below.
#task
def join_room(self):
host = 'xxxxxxx'
body = {
"room_id": self.room_id,
"userid": self.action_uid,
"uid": self.action_uid
}
rsp = self.client.post(url, json=body, headers=get_header(self.appkey))
if I exectue "locust -f StressTest/stress.py 'Qa' 123456 '101013' 686868 'eos' --headless -u 100 -r 100 --run-time 1m" , then throw " bogon/ERROR/locust.main: Unknown User(s): Qa, 686868, 123456, 101013, eos" error.

Answer 1

Try use *args, **kwargs and super() when inherit from Parent class. For that particular case, you don't provide uid, room_id, action_uid, appkey variables on the step of initialization, because HttpUser inherited from User, which has only one 1 argument - environment
class SimpleSendRequest(User):
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
for User class is more suggested to inherit from User class doc
if you really required to set variables to daughter object, you can set it on the step of initialization, just like that:
def __init__(self, env, *args, **kwargs):
super().__init__(env, *args, **kwargs)
self.uid = your_map['uid']
self.room_id = your_map['room_id']
self.action_id = your_map['action_uid']
self.appkey = your_map['appkey']
the only question, how are you going to use them
to add custom arguments, via CLI check github:
#events.init_command_line_parser.add_listener
def init_parser(parser):
parser.add_argument("--customarg", type=str, env_var="LOCUST_MY_ARGUMENT", default="1234", help="It's working")
#events.init.add_listener
def _(environment, **kw):
print("Custom argument supplied: %s" % environment.parsed_options.customarg)
to get it inside your class JoinRoomUser init, use:
print(self.environment.parsed_options.customarg)
and run like:
locust -f locustfile.py --customarg CUSTOM_VALUE --headless -u 10 -r 10 --run-time 5s