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Chrome 扩展程序

介绍​

¥Introduction

注意

扩展程序仅适用于通过持久上下文启动的 Chrome / Chromium。使用自定义浏览器参数需要你自担风险，因为其中一些参数可能会破坏 Playwright 功能。

¥Extensions only work in Chrome / Chromium launched with a persistent context. Use custom browser args at your own risk, as some of them may break Playwright functionality.

下面的代码片段检索源位于 ./my-extension 中的 清单 v2 扩展的 背景页。

¥The snippet below retrieves the background page of a Manifest v2 extension whose source is located in ./my-extension.

请注意使用 chromium 通道，该通道允许在无头模式下运行扩展。或者，你可以在头模式下启动浏览器。

¥Note the use of the chromium channel that allows to run extensions in headless mode. Alternatively, you can launch the browser in headed mode.

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,
        channel="chromium",
        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)

测试​

¥Testing

要在运行测试时加载扩展，你可以使用测试装置来设置上下文。例如，你还可以动态检索扩展 ID 并使用它来加载和测试弹出页面。

¥To have the extension loaded when running tests you can use a test fixture to set the context. You can also dynamically retrieve the extension id and use it to load and test the popup page for example.

请注意使用 chromium 通道，该通道允许在无头模式下运行扩展。或者，你可以在头模式下启动浏览器。

¥Note the use of the chromium channel that allows to run extensions in headless mode. Alternatively, you can launch the browser in headed mode.

首先，添加将加载扩展的装置：

¥First, add fixtures that will load the extension:

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(
        "",
        channel="chromium",
        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

然后在测试中使用这些装置：

¥Then use these fixtures in a test:

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")