Demonstrate how to execute parallel http get requests with requests in asyncio

parallel_requests_in_asyncio.py

"""Demonstrate how to execute parallel http get requests with requests in asyncio"""

import asyncio
import concurrent.futures
import requests

num_requests = 20

# Example 1: synchronous requests
def example_1():
    responses = [
        requests.get('http://example.org/')
        for i in range(num_requests)
    ]

# Example 2: asynchronous requests
def example_2():
    async def main():
        loop = asyncio.get_event_loop()
        futures = [
            loop.run_in_executor(
                None, 
                requests.get, 
                'http://example.org/'
            )
            for i in range(num_requests)
        ]
        for response in await asyncio.gather(*futures):
            pass
    loop = asyncio.get_event_loop()
    loop.run_until_complete(main())

# Example 3: asynchronous requests with larger thread pool
def example_3():
    async def main():
        with concurrent.futures.ThreadPoolExecutor(max_workers=20) as executor:
            loop = asyncio.get_event_loop()
            futures = [
                loop.run_in_executor(
                    executor, 
                    requests.get, 
                    'http://example.org/'
                )
                for i in range(num_requests)
            ]
            for response in await asyncio.gather(*futures):
                pass
    loop = asyncio.get_event_loop()
    loop.run_until_complete(main())