python批量发送邮件，通知

1. run_in_executer

import asyncio
import time

def sync_send_email():
    time.sleep(2)
    return "Done"

async def send_email():
    loop = asyncio.get_event_loop()
    result = await loop.run_in_executor(None, sync_send_email)  # 扔进线程池执行
    print(result)

asyncio.run(send_email())

2. 用asyncio.to_thread同步转异步‘

若是已经写好了同步发送邮件，则可以通过asyncio.to_thread同步转为异步发送

import asyncio
import time

def send_email():
    time.sleep(2)
    return "Done"

async def async_send_email():
    result = await asyncio.to_thread(send_email)  # 一行搞定！
    print(result)

asyncio.run(async_send_email())

3. 通过httpx异步发送邮件

异步直接实现发送邮件可以通过httpx实现，如下

async def async_send_email():
    async with httpx.AsyncClient(verify=False) as client:
        response = await client.post(
            f"https://{settings.domain}/email",
            json=data,
            cookies=cookies,
        )

4. 用信号量控制并发

# 用信号量（asyncio.Semaphore）控制并发
async def run_with_limit(task_func, max_cnotallow=50):
    semaphore = asyncio.Semaphore(max_concurrency)
    async def wrapper():
        async with semaphore:
            return await asyncio.to_thread(task_func)
    return wrapper

async def send_batch_email():
    tasks = [run_with_limit(send_one_email)() for _ in range(1000)]
    await asyncio.gather(*tasks)

asyncio.run(send_batch_email())

• 5. thread

thread = threading.Thread(func, *args)
thread.join()