i'm trying to create a simple program using python socket and threading library. I would like to automatize the following procedure using a decorator:
t = threading.Thread(target=function, args=(arg1, arg2))
t.start()
the program is structured using OOP so I defined a subclass inside the main one to contain all the decorators (I've read about this method in this article: https://medium.com/@vadimpushtaev/decorator-inside-python-class-1e74d23107f6). Therefore I have a situation like this:
class Server(object):
class Decorators(object):
@classmethod
def threaded_decorator(cls, function):
def inner_function():
function_thread = threading.Thread(target=function)
function_thread.start()
return inner_function
def __init__(self, other_arguments):
# other code
pass
@Decorators.threaded_decorator
def function_to_be_threaded(self):
# other code
pass
But when I try to run, I get the following error: TypeError: function_to_be_threaded() missing one required argument: 'self'
. I suspect that the issue is located in the part when I call the threading.Thread(target=function) which somehow doesn't pass the entire function self.function_to_be_threaded. Hence, if you know how to fix this, please can you tell me?. Also, can you tell me if there is a way to implement a decorator that accepts argument which will pass to the Thread class as args=(arguments_of_the_decorator)
?
Thank very much you for your time and excuse my English, I'm still practising it
Use *args
syntax to move the arguments.In other words, use *args
to collect all the positional arguments as a tuple and move it threading.Thread
as args
.
import threading
import time
class Server(object):
class Decorators(object):
@classmethod
def threaded_decorator(cls, function):
def inner_function(*args):
function_thread = threading.Thread(target=function,args=args)
function_thread.start()
return inner_function
def __init__(self, count,sleep):
self.count = count
self.sleep = sleep
@Decorators.threaded_decorator
def function_to_be_threaded(self,id):
for xx in range(self.count):
time.sleep(self.sleep)
print("{} ==> {}".format(id,xx))
>>> Server(6,1).function_to_be_threaded('a')
>>> Server(2,3).function_to_be_threaded('b')
a ==> 0
a ==> 1
a ==> 2
b ==> 0
a ==> 3
a ==> 4
a ==> 5
b ==> 1
see also How can I pass arguments from one function to another?