PyTandem

A multi-threaded event manager package for triggering methods in tandem groups.

Installation

Requirements

- python>=3.6

Install using PIP

python3 -m pip install --upgrade pytandem

Usage

First define the method(s) you would like to attach to the manager.

def print_num(num):
  print(num)

Then attach the method using the provided decorator - this will take an event name as a paramaneter. It should look like so:

from pytandem import pytandem

@pytandem.attach('event-name-here')
def print_num(num):
  print(num)

Whenever the above method (print_num()) is called, instead of being fired immediately it will be added to the manager threads to be started later on.

Next we can fire the method a few times:

for i in range(0, 3):
  print_num(i)

You'll notice nothing gets printed yet.

Now we can initiate the concurrent trigger of the 3 instances of the print_num() method we added to the threads earlier using the trigger() method - this, again, takes the event name as a parameter.

pytandem.trigger('event-name-here')

We can run the methods synchronously also by passing False in the threaded argument. This is set to True by default.

pytandem.trigger('event-name-here', threaded=False)

And lastly, we can also set the maximum number of concurrent threads that pytandem will use when triggering an event group. The default value for this is 4.

pytandem.trigger('event-name-here', max_threads=16)

Point to note: if max_threads is set to 4, and there are 20 methods attached on the same event name, then only 4 will run concurrently until one pops off the queue, essentially allowing the next in line to run. Methods will be fired according to the order in which they were first attached.

Note that a high max_threads value can cause out of memory issues if not careful.