Threading Class - 'int' not iterable | Flask - python-3.x

Question

I'm current encountering an issue where I'm using threads to perform tasks in the background upon a POST request, but I'm having an issue with using an integer as a parameter; or any data type as a parameter for that matter.
What is supposed to happen is that it's supposed to perform everything inside of the POST request check, then perform something else after that has been completed.
Imports:
from flask import Flask, url_for, render_template, redirect, request
from flask.cli import with_appcontext, click
import sqlalchemy
from flask_sqlalchemy import SQLAlchemy
from flask_login import LoginManager, login_required, current_user
Thread Class:
#click.command(name='run')
#click.pass_context
class Compute(Thread):
def __init__(self, secs):
Thread.__init__(self)
self.secs = secs
def run(self):
print('Thread Opened')
sleep(self.secs)
db.session.query(Users).filter(Users.username == current_user.username).first().requests += 1
db.session.commit()
print('Thread Closed')
Flask Route:
#app.route('/index', methods=['GET', 'POST'])
#login_required
def index():
if request.method == 'POST':
time = '5'
thread = Compute(int(time))
thread.start()
return redirect(url_for('index'))
else:
return render_template('index.html')
The error I am receiving when the thread tries to start is this:
Traceback (most recent call last):
File "C:\Users\myuser\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.7_qbz5n2kfra8p0\LocalCache\local-packages\Python37\site-packages\flask\app.py", line 2447, in wsgi_app
response = self.full_dispatch_request()
File "C:\Users\myuser\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.7_qbz5n2kfra8p0\LocalCache\local-packages\Python37\site-packages\flask\app.py", line 1952, in full_dispatch_request rv = self.handle_user_exception(e)
File "C:\Users\myuser\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.7_qbz5n2kfra8p0\LocalCache\local-packages\Python37\site-packages\flask\app.py", line 1821, in handle_user_exception reraise(exc_type, exc_value, tb)
File "C:\Users\myuser\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.7_qbz5n2kfra8p0\LocalCache\local-packages\Python37\site-packages\flask\_compat.py", line 39, in reraise
raise value
File "C:\Users\myuser\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.7_qbz5n2kfra8p0\LocalCache\local-packages\Python37\site-packages\flask\app.py", line 1950, in full_dispatch_request rv = self.dispatch_request()
File "C:\Users\myuser\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.7_qbz5n2kfra8p0\LocalCache\local-packages\Python37\site-packages\flask\app.py", line 1936, in dispatch_request
return self.view_functions[rule.endpoint](**req.view_args)
File "C:\Users\myuser\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.7_qbz5n2kfra8p0\LocalCache\local-packages\Python37\site-packages\flask_login\utils.py", line 272, in decorated_view return func(*args, **kwargs)
File "c:/Users/myuser/Desktop/Projects/Python/app.py", line 104, in layer4
thread = Compute(int(time))
File "C:\Users\myuser\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.7_qbz5n2kfra8p0\LocalCache\local-packages\Python37\site-packages\click\core.py", line 829, in __call__
return self.main(*args, **kwargs)
File "C:\Users\myuser\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.7_qbz5n2kfra8p0\LocalCache\local-packages\Python37\site-packages\click\core.py", line 767, in main
args = list(args)
TypeError: 'int' object is not iterable
I am not very experienced with threading, I've only dabbled with it in other projects so I'm not sure why I'm getting this error; any help is greatly appreciated.

Answer 1

You need to remove the #click.command and #click.pass_context decorators.
#click.command(name='run')
#click.pass_context
class Compute(Thread):
Those decorators are wrapping the class in a function that takes its own parameters. It is intended for running a function from the command line and parsing arguments. This is why the traceback shows args = list(args) as the line causing the error.
https://github.com/pallets/click/blob/master/src/click/core.py#L916-L917
:param args: the arguments that should be used for parsing. If not
provided, ``sys.argv[1:]`` is used.