Question

I’m using web.py framework. For debugging purposes, I’d like to force all requests to be handled by a single thread, or simulate such behaviour with a mutex. How can I do that?

Answer 1

Let me suggest something like this, but it will lock only current application stack over your controller method.

import web
from threading import Lock

urls = ("/", "Index")


class Index:

    def GET(self):
        # This will be locked
        return "hello world"


def mutex_processor():
    mutex = Lock()

    def processor_func(handle):
        mutex.acquire()
        try:
            return handle()
        finally:
            mutex.release()
    return processor_func

app = web.application(urls, globals())

app.add_processor(mutex_processor())

if __name__ == "__main__":
    app.run()

UPD: if you need to lock the whole application stack then you probably have to wrap app.wsgifunc with your own WSGI middleware. To get an idea check my answer to this question.