asyncio_semaphore_example.py

import asyncio
import aiohttp

# Example async function that simulates making an API call
async def make_api_call(semaphore, session, task_id):
    async with semaphore:  # Ensure we respect the semaphore limit
        print(f"Task {task_id}: Starting API call...")
        try:
            async with session.get(f"https://httpbin.org/get?task={task_id}") as response:
                result = await response.json()
                print(f"Task {task_id}: Completed with response {result['args']}")
                return result['args']
        except Exception as e:
            print(f"Task {task_id}: Failed with error {e}")
            return None

def main():
    num_tasks = 50
    semaphore_limit = 30
    semaphore = asyncio.Semaphore(semaphore_limit)

    async def run_tasks():
        async with aiohttp.ClientSession() as session:
            tasks = [make_api_call(semaphore, session, task_id) for task_id in range(1, num_tasks + 1)]
            results = await asyncio.gather(*tasks)
            return results

    # Run the event loop and get the results
    results = asyncio.run(run_tasks())
    print("All tasks completed.")
    print("Results:", results)

if __name__ == "__main__":
    main()