Chrome 擴充功能

簡介

note

擴充功能僅在使用持久性上下文啟動的 Chrome / Chromium 中工作。使用自訂瀏覽器參數需自行承擔風險，因為其中一些可能會破壞 Playwright 功能。

以下是取得 background page 的程式碼，這個 Manifest v2 擴充套件的來源位於 ./my-extension：

Sync

from playwright.sync_api import sync_playwright, Playwright

path_to_extension = "./my-extension"
user_data_dir = "/tmp/test-user-data-dir"


def run(playwright: Playwright):
    context = playwright.chromium.launch_persistent_context(
        user_data_dir,
        headless=False,
        args=[
            f"--disable-extensions-except={path_to_extension}",
            f"--load-extension={path_to_extension}",
        ],
    )
    if len(context.background_pages) == 0:
        background_page = context.wait_for_event('backgroundpage')
    else:
        background_page = context.background_pages[0]

    # Test the background page as you would any other page.
    context.close()


with sync_playwright() as playwright:
    run(playwright)

Async

import asyncio
from playwright.async_api import async_playwright, Playwright

path_to_extension = "./my-extension"
user_data_dir = "/tmp/test-user-data-dir"


async def run(playwright: Playwright):
    context = await playwright.chromium.launch_persistent_context(
        user_data_dir,
        headless=False,
        args=[
            f"--disable-extensions-except={path_to_extension}",
            f"--load-extension={path_to_extension}",
        ],
    )

    if len(context.background_pages) == 0:
        background_page = await context.wait_for_event('backgroundpage')
    else:
        background_page = context.background_pages[0]

    # Test the background page as you would any other page.
    await context.close()


async def main():
    async with async_playwright() as playwright:
        await run(playwright)


asyncio.run(main())

測試

為了在執行測試時載入擴充功能，您可以使用測試裝置來設定上下文。您也可以動態檢索擴充功能 ID，並使用它來載入和測試彈出頁面範例。

首先，新增將載入擴充功能的固定裝置:

conftest.py

from typing import Generator
from pathlib import Path
from playwright.sync_api import Playwright, BrowserContext
import pytest


@pytest.fixture()
def context(playwright: Playwright) -> Generator[BrowserContext, None, None]:
    path_to_extension = Path(__file__).parent.joinpath("my-extension")
    context = playwright.chromium.launch_persistent_context(
        "",
        headless=False,
        args=[
            f"--disable-extensions-except={path_to_extension}",
            f"--load-extension={path_to_extension}",
        ],
    )
    yield context
    context.close()


@pytest.fixture()
def extension_id(context) -> Generator[str, None, None]:
    # for manifest v2:
    # background = context.background_pages[0]
    # if not background:
    #     background = context.wait_for_event("backgroundpage")

    # for manifest v3:
    background = context.service_workers[0]
    if not background:
        background = context.wait_for_event("serviceworker")

    extension_id = background.url.split("/")[2]
    yield extension_id

然後在測試中使用這些裝置:

test_foo.py

from playwright.sync_api import expect, Page


def test_example_test(page: Page) -> None:
    page.goto("https://example.com")
    expect(page.locator("body")).to_contain_text("Changed by my-extension")


def test_popup_page(page: Page, extension_id: str) -> None:
    page.goto(f"chrome-extension://{extension_id}/popup.html")
    expect(page.locator("body")).to_have_text("my-extension popup")

無頭模式

danger

headless=new 模式不受 Playwright 官方支持，可能會導致意外行為。

預設情況下，Chrome 在 Playwright 中的無頭模式不支援 Chrome 擴充功能。為了克服這一限制，你可以使用以下程式碼在新的無頭模式下執行 Chrome 的持久性上下文:

conftest.py

path_to_extension = Path(__file__).parent.joinpath("my-extension")
context = playwright.chromium.launch_persistent_context(
    "",
    headless=False,
    args=[
        "--headless=new",
        f"--disable-extensions-except={path_to_extension}",
        f"--load-extension={path_to_extension}",
    ],
)