Pyppeteer - 单击链接后运行 page.content() 时出错

问题描述

JS/Html 初学者，我试图在点击链接后通过 pyppeteer0.2.5 (python3.6.9/Chromium 87.0.4280.66) 使用以下代码获取页面内容：

import asyncio,pyppeteer,time
from pyppeteer import launch

async def main():
    browser = await launch(executablePath='/usr/bin/chromium-browser',headless=False)
    page = await browser.newPage()
    await page.goto('https://en.wikipedia.org')
    time.sleep(10)
    cont = await page.content()
    print(cont)
asyncio.get_event_loop().run_until_complete(main())

1. 如果我在 time.sleep(10) 期间没有点击或执行任何操作，维基百科主页面内容会在 10 秒后按预期打印。
2. 如果我在 time.sleep(10) 期间（手动）点击任何链接，新页面会按预期打开，但 10 秒后我收到 Python 错误（见下文）。我在不同的网页上以及通过 pyppeteer 而不是手动点击时也发生了同样的情况。点击链接后 page.content() 失败是否有原因？

    Traceback (most recent call last):
      File "/home/martin/.local/lib/python3.6/site-packages/pyppeteer/execution_context.py",line 105,in evaluateHandle
        'userGesture': True,pyppeteer.errors.NetworkError: Protocol error (Runtime.callFunctionOn): Cannot find context with specified id
    
    During handling of the above exception,another exception occurred:
    
    Traceback (most recent call last):
      File "To_delete/pythonProject/testtt.py",line 11,in <module>
        asyncio.get_event_loop().run_until_complete(main())
      File "/usr/lib/python3.6/asyncio/base_events.py",line 484,in run_until_complete
        return future.result()
      File "To_delete/pythonProject/testtt.py",line 9,in main
        cont = await page.content()
      File "/home/martin/.local/lib/python3.6/site-packages/pyppeteer/page.py",line 803,in content
        return await frame.content()
      File "/home/martin/.local/lib/python3.6/site-packages/pyppeteer/frame_manager.py",line 393,in content
        '''.strip())
      File "/home/martin/.local/lib/python3.6/site-packages/pyppeteer/frame_manager.py",line 309,in evaluate
        pageFunction,*args,force_expr=force_expr)
      File "/home/martin/.local/lib/python3.6/site-packages/pyppeteer/execution_context.py",line 54,line 108,in evaluateHandle
        _rewriteError(e)
      File "/home/martin/.local/lib/python3.6/site-packages/pyppeteer/execution_context.py",line 237,in _rewriteError
        raise type(error)(msg)
    pyppeteer.errors.NetworkError: Execution context was destroyed,most likely because of a navigation.

解决方法

事实证明，我需要在 await page.waitForNavigation() 上方添加 await page.content() 才能使其工作。