CODEWITHSUNDEEP
pythonmultithreadingbottle
Renato Oliveira
Renato Oliveira

Reputation: 504

Threading with Bottle.py Server

I'm having an issue with threading that I can't solve in any way I've tried. I searched in StackOverflow too, but all I could find was cases that didn't apply to me, or explanations that I didn't understand.

I'm trying to build an app with BottlePy, and one of the features I want requires a function to run in background. For this, I'm trying to make it run in a thread. However, when I start the thread, it runs twice.

I've read in some places that it would be possible to check if the function was in the main script or in a module using if __name__ == '__main__':, however I'm not able to do this, since __name__ is always returning the name of the module.

Below is an example of what I'm doing right now.

The main script:

# main.py
from MyClass import *
from bottle import *

arg = something

myObject = Myclass(arg1)

app = Bottle()
app.run('''bottle args''')

The class:

# MyClass.py
import threading
import time

class MyClass:
    def check_list(self, theList, arg1):
        a_list = something()
        time.sleep(5)
        self.check_list(a_list, arg1)

    def __init__(self, arg1):
        if __name__ == '__main__':
            self.a_list = arg.returnAList()
            t = threading.Thread(target=self.check_list, args=(a_list, arg1))

So what I intend here is to have check_list running in a thread all the time, doing something and waiting some seconds to run again. All this so I can have the list updated, and be able to read it with the main script.

Can you explain to me what I'm doing wrong, why the thread is running twice, and how can I avoid this?

Upvotes: 2

Views: 2235

Answers (2)

Renato Oliveira
Renato Oliveira

Reputation: 504

Figured out what was wrong thanks to the user Weeble's comment. When he said 'something is causing your main.py to run twice' I remembered that Bottle has an argument that is called 'reloader'. When set to True, this will make the application load twice, and thus the thread creation is run twice as well.

Upvotes: 1

Mel
Mel

Reputation: 6065

This works fine:

import threading
import time

class MyClass:
    def check_list(self, theList, arg1):
        keep_going=True
        while keep_going:
            print("check list")
            #do stuff
            time.sleep(1)

    def __init__(self, arg1):
        self.a_list = ["1","2"]
        t = threading.Thread(target=self.check_list, args=(self.a_list, arg1))
        t.start()

myObject = MyClass("something")

Upvotes: 1

Related Questions