Pyppeteer：浏览器在 AWS Lambda 中意外关闭

Question

我在 AWS Lambda 中遇到了这个错误。似乎 devtools websocket 没有启动。不知道如何修复它。有任何想法吗？谢谢你的时间。

异常源于get_ws_endpoint()websocket 响应超时https://github.com/pyppeteer/pyppeteer/blob/ad3a0a7da221a04425cbf0cc92e50e93883b077b/pyppeteer/launcher.py#L225

拉姆达代码：

import os
import json
import asyncio
import logging
import boto3
import pyppeteer
from pyppeteer import launch

logger = logging.getLogger()
logger.setLevel(logging.INFO)

pyppeteer.DEBUG = True  # print suppressed errors as error log

def lambda_handler(event, context):
    asyncio.get_event_loop().run_until_complete(main())

async def main():
    browser = await launch({
        'headless': True,
        'args': [
            '--no-sandbox'
            ]
    })
    page = await browser.newPage()
    await page.goto('http://example.com')
    await page.screenshot({'path': '/tmp/example.png'})
    await browser.close()
    return {
        'statusCode': 200,
        'body': json.dumps('Hello from Lambda!')
    }

例外：

    Response:
{
  "errorMessage": "Browser closed unexpectedly:\n",
  "errorType": "BrowserError",
  "stackTrace": [
    "  File \"/var/task/lambda_handler.py\", line 23, in lambda_handler\n    asyncio.get_event_loop().run_until_complete(main())\n",
    "  File \"/var/lang/lib/python3.8/asyncio/base_events.py\", line 616, in run_until_complete\n    return future.result()\n",
    "  File \"/var/task/lambda_handler.py\", line 72, in main\n    browser = await launch({\n",
    "  File \"/opt/python/pyppeteer/launcher.py\", line 307, in launch\n    return await Launcher(options, **kwargs).launch()\n",
    "  File \"/opt/python/pyppeteer/launcher.py\", line 168, in launch\n    self.browserWSEndpoint = get_ws_endpoint(self.url)\n",
    "  File \"/opt/python/pyppeteer/launcher.py\", line 227, in get_ws_endpoint\n    raise BrowserError('Browser closed unexpectedly:\\n')\n"
  ]
}

Request ID:
"06be0620-8b5c-4600-a76e-bc785210244e"

Function Logs:
START RequestId: 06be0620-8b5c-4600-a76e-bc785210244e Version: $LATEST
---- files in /tmp ----
[W:pyppeteer.chromium_downloader] start chromium download.
Download may take a few minutes.

  0%|          | 0/108773488 [00:00<?, ?it/s]
 11%|??        | 12267520/108773488 [00:00<00:00, 122665958.31it/s]
 27%|???       | 29470720/108773488 [00:00<00:00, 134220418.14it/s]
 42%|?????     | 46172160/108773488 [00:00<00:00, 142570388.86it/s]
 58%|??????    | 62607360/108773488 [00:00<00:00, 148471487.93it/s]
 73%|????????  | 79626240/108773488 [00:00<00:00, 154371569.93it/s]
 88%|????????? | 95754240/108773488 [00:00<00:00, 156353972.12it/s]
100%|??????????| 108773488/108773488 [00:00<00:00, 161750092.47it/s]
[W:pyppeteer.chromium_downloader] 
chromium download done.
[W:pyppeteer.chromium_downloader] chromium extracted to: /tmp/local-chromium/588429
-----
/tmp/local-chromium/588429/chrome-linux/chrome
[ERROR] BrowserError: Browser closed unexpectedly:

Traceback (most recent call last):
  File "/var/task/lambda_handler.py", line 23, in lambda_handler
    asyncio.get_event_loop().run_until_complete(main())
  File "/var/lang/lib/python3.8/asyncio/base_events.py", line 616, in run_until_complete
    return future.result()
  File "/var/task/lambda_handler.py", line 72, in main
    browser = await launch({
  File "/opt/python/pyppeteer/launcher.py", line 307, in launch
    return await Launcher(options, **kwargs).launch()
  File "/opt/python/pyppeteer/launcher.py", line 168, in launch
    self.browserWSEndpoint = get_ws_endpoint(self.url)
  File "/opt/python/pyppeteer/launcher.py", line 227, in get_ws_endpoint
    raise BrowserError('Browser closed unexpectedly:\n')END RequestId: 06be0620-8b5c-4600-a76e-bc785210244e
REPORT RequestId: 06be0620-8b5c-4600-a76e-bc785210244e  Duration: 33370.61 ms   Billed Duration: 33400 ms   Memory Size: 3008 MB    Max Memory Used: 481 MB Init Duration: 445.58 ms    

Answer 1

我认为BrowserError: Browser closed unexpectedly这只是 Chrome 因任何原因崩溃时遇到的错误。如果 pyppeteer 打印出错误就好了，但事实并非如此。

为了跟踪事情，拉出 pyppeteer 运行的确切命令是有帮助的。你可以这样做：

>>> from pyppeteer.launcher import Launcher
>>> ' '.join(Launcher().cmd)
/root/.local/share/pyppeteer/local-chromium/588429/chrome-linux/chrome --disable-background-networking --disable-background-timer-throttling --disable-breakpad --disable-browser-side-navigation --disable-client-side-phishing-detection --disable-default-apps --disable-dev-shm-usage --disable-extensions --disable-features=site-per-process --disable-hang-monitor --disable-popup-blocking --disable-prompt-on-repost --disable-sync --disable-translate --metrics-recording-only --no-first-run --safebrowsing-disable-auto-update --enable-automation --password-store=basic --use-mock-keychain --headless --hide-scrollbars --mute-audio about:blank --no-sandbox --remote-debugging-port=33423 --user-data-dir=/root/.local/share/pyppeteer/.dev_profile/tmp5cj60q6q

当我在 Docker 映像中运行该命令时，出现以下错误：

$ /root/.local/share/pyppeteer/local-chromium/588429/chrome-linux/chrome # ...
/root/.local/share/pyppeteer/local-chromium/588429/chrome-linux/chrome:
error while loading shared libraries:
libnss3.so: cannot open shared object file: No such file or directory

所以我安装了libnss3：

apt-get install -y libnss3

然后我再次运行命令并得到一个不同的错误：

$ /root/.local/share/pyppeteer/local-chromium/588429/chrome-linux/chrome # ...
[0609/190651.188666:ERROR:zygote_host_impl_linux.cc(89)] Running as root without --no-sandbox is not supported. See https://crbug.com/638180.

所以我需要将我的启动命令更改为：

>>> from pyppeteer.launcher import Launcher
>>> ' '.join(Launcher().cmd)
/root/.local/share/pyppeteer/local-chromium/588429/chrome-linux/chrome --disable-background-networking --disable-background-timer-throttling --disable-breakpad --disable-browser-side-navigation --disable-client-side-phishing-detection --disable-default-apps --disable-dev-shm-usage --disable-extensions --disable-features=site-per-process --disable-hang-monitor --disable-popup-blocking --disable-prompt-on-repost --disable-sync --disable-translate --metrics-recording-only --no-first-run --safebrowsing-disable-auto-update --enable-automation --password-store=basic --use-mock-keychain --headless --hide-scrollbars --mute-audio about:blank --no-sandbox --remote-debugging-port=33423 --user-data-dir=/root/.local/share/pyppeteer/.dev_profile/tmp5cj60q6q

现在它起作用了！

Answer 2

回答我自己的问题。

最后，在将 chromium 二进制文件捆绑到 lambda 层后，我能够使用 Python 3.6 和 3.7（不是 3.8）运行 Pyppeteer(v0.2.2)。

总而言之，它似乎仅在配置为使用用户提供的 chromium 可执行路径运行而不是自动下载的 chrome 时才起作用。可能是某种竞争条件或其他什么。

从https://github.com/adieuadieu/serverless-chrome/releases/download/v1.0.0-41/stable-headless-chromium-amazonlinux-2017-03.zip获取 Chromium

browser = await launch(
        headless=True, 
        executablePath='/opt/python/headless-chromium',
        args=[
            '--no-sandbox',
            '--single-process',
            '--disable-dev-shm-usage',
            '--disable-gpu',
            '--no-zygote'
        ])

问题发布在仓库https://github.com/pyppeteer/pyppeteer/issues/108