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我有一个 Django 站点，该站点使用该trio_cdp包使用无头 Google Chrome 生成 PDF。这个包是异步的，但是我的Django项目是同步的，所以它必须在里面运行trio.run()

它还使用 uwsgi 锁，以便一次只有一个客户端可以生成 PDF（无头 Chrome 将页面加载到单个虚拟选项卡中，因此一次只能生成一个）

这是代码：

import trio
import base64
import requests
from django.conf import settings
from trio_cdp import open_cdp, page, target

try:
    import uwsgi
    have_uwsgi = True
except ModuleNotFoundError:
    have_uwsgi = False

async def render_pdf_task(url, params):
    r = requests.get(url=settings.CDP_URL)
    if r.status_code == 200:
        out = r.json()
        ws_url = out[0]['webSocketDebuggerUrl']
    else:
        return None
    async with open_cdp(ws_url) as conn:
        targets = await target.get_targets()
        target_id = targets[0].target_id
        async with conn.open_session(target_id) as session:
            async with session.page_enable():
                async with session.wait_for(page.LoadEventFired):
                    await page.navigate(url)
                await trio.sleep(0.5)
                pdf = await page.print_to_pdf(**params)
                pdfdata = base64.b64decode(pdf[0])
        await conn.aclose()
    return pdfdata

def render_pdf(url, params):
    if have_uwsgi:
        uwsgi.lock(1)
    pdfdata = trio.run(render_pdf_task, url, params)
    if have_uwsgi:
        uwsgi.unlock(1)
    return pdfdata

令人讨厌的是，任何运行此特定任务的 uwsgi 工作人员稍后都会在退出时挂起，直到它被强行杀死。如果 uwsgi 运行并且没有人访问 PDF 生成页面，则所有 uwsgi 工作人员都可以正常退出。运行 render_pdf 函数的 uwsgi 工作人员始终需要被杀死。

比如pid 20887运行了render_pdf，后来在尝试关闭uwsgi的时候，出现了这样的情况：

SIGINT/SIGQUIT received...killing workers...
worker 10 buried after 1 seconds
worker 9 buried after 1 seconds
worker 7 buried after 1 seconds
worker 6 buried after 1 seconds
worker 5 buried after 1 seconds
worker 4 buried after 1 seconds
worker 3 buried after 1 seconds
worker 2 buried after 1 seconds
worker 1 buried after 1 seconds
Tue Jan 25 22:44:42 2022 - worker 8 (pid: 20887) is taking too much time to die...NO MERCY !!!
worker 8 buried after 1 seconds
goodbye to uWSGI.

How can I fix this? Any help is much appreciated :)

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1 回答 1

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I was able to solve this myself. uWSGI's handler for SIGINT is overridden by trio.run(), but only if trio.run() is in the main thread. I solved this by running it in another thread.

于 2022-02-05T13:11:47.983 回答