Python - Running IO tasks in parallel

Python(3.2 later version) has a feature to run IO tasks in parallel by using futures and ThreadPoolExecutor.

The below code will show an example for sending multiple HTTP requests.

import http.client
import ssl
import json
from concurrent.futures import ThreadPoolExecutor

def connect_https_server(host_name, port_number):
    host_end_point_address = host_name + ":" + str(port_number)
    return http.client.HTTPSConnection(host_end_point_address, timeout=30, context=ssl._create_unverified_context())


def send_http_query(host_name, port_number):
    conn = connect_https_server(host_name, port_number)
    query = f"/version"
    conn.request("GET", query)
    res = conn.getresponse()
    data = res.read()
    conn.close()

    output = data.decode('utf-8')
    return output


def run_queries_in_parallel(tasks):
    with ThreadPoolExecutor() as executor:
        result = []
        running_tasks = [executor.submit(task) for task in tasks]
        for running_task in running_tasks:
            res = running_task.result()
            result.append(result)

        return result


def make_task(host_name, port_number):
    return lambda: send_http_query(host_name, port_number)


def parallel_tasks_demo():
    host_names = ["test1", "test2", "test3"]
    task_list = []
    for host_name in host_names:
        task_list.append(make_task(host_name, 8080))

    run_queries_in_parallel(task_list, output_path)