Asyncio Example with Function and Subprocess

asyncio.py

import asyncio
import glob
import aiofiles
import subprocess


async def read_file(f):
    print("start: " + f)
    async with aiofiles.open(f, 'r') as fd:
        lines = await fd.read()
    return lines


async def print_file(f):
    args = ["echo", f'"{f}"']
    process = await asyncio.create_subprocess_exec(
        *args, stdout=asyncio.subprocess.PIPE, stderr=asyncio.subprocess.PIPE
    )

    # Status
    print("Started: %s, pid=%s" % (args, process.pid), flush=True)

    # Wait for the subprocess to finish
    stdout, stderr = await process.communicate()

    # Progress
    if process.returncode == 0:
        print(
            "Done: %s, pid=%s, result: %s"
            % (args, process.pid, stdout.decode().strip()),
            flush=True,
        )
    else:
        print(
            "Failed: %s, pid=%s, result: %s"
            % (args, process.pid, stderr.decode().strip()),
            flush=True,
        )

    # Result
    result = stdout.decode().strip()

    # Return stdout
    return result


async def main():
    for x in await asyncio.gather(*list(map(read_file, glob.glob('sql/*.sql')))):
        await print_file(x)


if __name__ == '__main__':
    asyncio.run(main())