Question

How do I pass multiple arguments to a function I call through pool.map?

My code:

import gevent
from gevent.pool import Pool

def process(param1, param2):
    return "dosomething"

pool = Pool(10)
jobs = [('arg1a', 'arg1b'), ('arg2a', 'arg2b')]

# should pass arguments so that it results in these calls
# process(param1=arg1a, param2=arg1b)
# process(param1=arg2a, param2=arg2b)
results = pool.map(process, jobs) # does not work

Answer 1

It appears the gevent.Pool.map method only allows a single item to be passed as an argument to the function you provide. However, you can code the function to unpack its arguments pretty easily:

def process(params):
    param1, param2 = params
    ...

Or you could handle the argument unpacking with a lambda expression right in your call to pool.map:

results = pool.map(lambda args: process(*args), jobs)