scrapy-playwright 0.0.17

Playwright integration for Scrapy

scrapy-playwright: Playwright integration for Scrapy

A Scrapy Download Handler which performs requests using Playwright for Python. It can be used to handle pages that require JavaScript (among other things), while adhering to the regular Scrapy workflow (i.e. without interfering with request scheduling, item processing, etc).

Requirements

After the release of version 2.0, which includes coroutine syntax support and asyncio support, Scrapy allows to integrate asyncio-based projects such as Playwright.

Minimum required versions

• Python >= 3.7
• Scrapy >= 2.0 (!= 2.4.0)
• Playwright >= 1.15

Installation

$ pip install scrapy-playwright

Changelog

Please see the changelog.md file.

Activation

Replace the default http and/or https Download Handlers through DOWNLOAD_HANDLERS:

DOWNLOAD_HANDLERS = {
    "http": "scrapy_playwright.handler.ScrapyPlaywrightDownloadHandler",
    "https": "scrapy_playwright.handler.ScrapyPlaywrightDownloadHandler",
}

Note that the ScrapyPlaywrightDownloadHandler class inherits from the default http/https handler. Unless explicitly marked (see the "Basic usage"), requests will be processed by the regular Scrapy download handler.

Also, be sure to install the asyncio-based Twisted reactor:

TWISTED_REACTOR = "twisted.internet.asyncioreactor.AsyncioSelectorReactor"

Supported settings

• PLAYWRIGHT_BROWSER_TYPE (type str, default chromium) The browser type to be launched, e.g. chromium, firefox, webkit.

• PLAYWRIGHT_LAUNCH_OPTIONS (type dict, default {})

  A dictionary with options to be passed when launching the Browser. See the docs for BrowserType.launch.

• PLAYWRIGHT_CONTEXTS (type dict[str, dict], default {})

  A dictionary which defines Browser contexts to be created on startup. It should be a mapping of (name, keyword arguments). For instance:

  {
      "foobar": {
          "context_arg1": "value",
          "context_arg2": "value",
      },
      "default": {
          "context_arg1": "value",
          "context_arg2": "value",
      },
      "persistent": {
          "user_data_dir": "/path/to/dir",  # will be a persistent context
          "context_arg1": "value",
      },
  }
  

  See the section on browser contexts for more information.

  See also the docs for Browser.new_context.

• PLAYWRIGHT_MAX_CONTEXTS (type Optional[int], default None)

  Maximum amount of allowed concurrent Playwright contexts. If unset or None, no limit is enforced. See the Maximum concurrent context count section for more information.

• PLAYWRIGHT_DEFAULT_NAVIGATION_TIMEOUT (type Optional[float], default None)

  The timeout used when requesting pages by Playwright. If None or unset, the default value will be used (30000 ms at the time of writing this). See the docs for BrowserContext.set_default_navigation_timeout.

• PLAYWRIGHT_PROCESS_REQUEST_HEADERS (type Optional[Union[Callable, str]], default scrapy_playwright.headers.use_scrapy_headers)

  A function (or the path to a function) that processes headers for a given request and returns a dictionary with the headers to be used (note that, depending on the browser, additional default headers could be sent as well). Coroutine functions (async def) are supported.

  This will be called at least once for each Scrapy request (receiving said request and the corresponding Playwright request), but it could be called additional times if the given resource generates more requests (e.g. to retrieve assets like images or scripts).

  The function must return a dict object, and receives the following keyword arguments:

  - browser_type: str
  - playwright_request: playwright.async_api.Request
  - scrapy_headers: scrapy.http.headers.Headers
  

  The default value (scrapy_playwright.headers.use_scrapy_headers) tries to emulate Scrapy's behaviour for navigation requests, i.e. overriding headers with their values from the Scrapy request. For non-navigation requests (e.g. images, stylesheets, scripts, etc), only the User-Agent header is overriden, for consistency.

  Setting PLAYWRIGHT_PROCESS_REQUEST_HEADERS=None will give complete control of the headers to Playwright, i.e. headers from Scrapy requests will be ignored and only headers set by Playwright will be sent. When doing this, please keep in mind that headers passed via the Request.headers attribute or set by Scrapy components are ignored (including cookies set via the Request.cookies attribute).

• PLAYWRIGHT_MAX_PAGES_PER_CONTEXT (type int, defaults to the value of Scrapy's CONCURRENT_REQUESTS setting)

  Maximum amount of allowed concurrent Playwright pages for each context. See the notes about leaving unclosed pages.

• PLAYWRIGHT_ABORT_REQUEST (type Optional[Union[Callable, str]], default None)

  A predicate function (or the path to a function) that receives a playwright.async_api.Request object and must return True if the request should be aborted, False otherwise. Coroutine functions (async def) are supported.

  For instance, the following are all equivalent, and prevent the download of images:

  PLAYWRIGHT_ABORT_REQUEST = lambda req: req.resource_type == "image"
  

  def should_abort_request(req):
      return req.resource_type == "image"
  
  PLAYWRIGHT_ABORT_REQUEST = should_abort_request
  

  # project/utils.py
  def should_abort_request(req):
      return req.resource_type == "image"
  
  # settings.py
  PLAYWRIGHT_ABORT_REQUEST = "project.utils.should_abort_request"
  

  Please note that all requests will appear in the DEBUG level logs, however there will be no corresponding response log lines for aborted requests. Aborted requests are counted in the playwright/request_count/aborted job stats item.

  General note about settings

  For the settings which accept object paths as strings, passing callable objects is only supported when using Scrapy>=2.4. With prior versions, only strings are supported.

Basic usage

Set the playwright Request.meta key to download a request using Playwright:

import scrapy

class AwesomeSpider(scrapy.Spider):
    name = "awesome"

    def start_requests(self):
        # GET request
        yield scrapy.Request("https://httpbin.org/get", meta={"playwright": True})
        # POST request
        yield scrapy.FormRequest(
            url="https://httpbin.org/post",
            formdata={"foo": "bar"},
            meta={"playwright": True},
        )

    def parse(self, response):
        # 'response' contains the page as seen by the browser
        yield {"url": response.url}

Notes about the User-Agent header

By default, outgoing requests include the User-Agent set by Scrapy (either with the USER_AGENT or DEFAULT_REQUEST_HEADERS settings or via the Request.headers attribute). This could cause some sites to react in unexpected ways, for instance if the user agent does not match the running Browser. If you prefer the User-Agent sent by default by the specific browser you're using, set the Scrapy user agent to None.

Receiving Page objects in callbacks

Specifying a non-False value for the playwright_include_page meta key for a request will result in the corresponding playwright.async_api.Page object being available in the playwright_page meta key in the request callback. In order to be able to await coroutines on the provided Page object, the callback needs to be defined as a coroutine function (async def).

import scrapy

class AwesomeSpiderWithPage(scrapy.Spider):
    name = "page"

    def start_requests(self):
        yield scrapy.Request(
            url="https://example.org",
            meta={"playwright": True, "playwright_include_page": True},
            errback=self.errback,
        )

    async def parse(self, response):
        page = response.meta["playwright_page"]
        title = await page.title()  # "Example Domain"
        await page.close()
        return {"title": title}

    async def errback(self, failure):
        page = failure.request.meta["playwright_page"]
        await page.close()

Notes:

• In order to avoid memory issues, it is recommended to manually close the page by awaiting the Page.close coroutine.
• Be careful about leaving pages unclosed, as they count towards the limit set by PLAYWRIGHT_MAX_PAGES_PER_CONTEXT. When passing playwright_include_page=True, it's recommended to set a Request errback to make sure pages are closed even if a request fails (if playwright_include_page=False or unset, pages are automatically closed upon encountering an exception).
• Any network operations resulting from awaiting a coroutine on a Page object (goto, go_back, etc) will be executed directly by Playwright, bypassing the Scrapy request workflow (Scheduler, Middlewares, etc).

Browser contexts

Multiple browser contexts to be launched at startup can be defined via the PLAYWRIGHT_CONTEXTS setting.

Choosing a specific context for a request

Pass the name of the desired context in the playwright_context meta key:

yield scrapy.Request(
    url="https://example.org",
    meta={"playwright": True, "playwright_context": "first"},
)

Default context

If a request does not explicitly indicate a context via the playwright_context meta key, it falls back to using a general context called default. This default context can also be customized on startup via the PLAYWRIGHT_CONTEXTS setting.

Persistent contexts

Pass a value for the user_data_dir keyword argument to launch a context as persistent (see BrowserType.launch_persistent_context).

Creating a context during a crawl

If the context specified in the playwright_context meta key does not exist, it will be created. You can specify keyword arguments to be passed to Browser.new_context in the playwright_context_kwargs meta key:

yield scrapy.Request(
    url="https://example.org",
    meta={
        "playwright": True,
        "playwright_context": "new",
        "playwright_context_kwargs": {
            "java_script_enabled": False,
            "ignore_https_errors": True,
            "proxy": {
                "server": "http://myproxy.com:3128",
                "username": "user",
                "password": "pass",
            },
        },
    },
)

Please note that if a context with the specified name already exists, that context is used and playwright_context_kwargs are ignored.

Closing a context during a crawl

After receiving the Page object in your callback, you can access a context though the corresponding Page.context attribute, and await close on it.

def parse(self, response):
    yield scrapy.Request(
        url="https://example.org",
        callback=self.parse_in_new_context,
        errback=self.close_context_on_error,
        meta={"playwright": True, "playwright_context": "new", "playwright_include_page": True},
    )

async def parse_in_new_context(self, response):
    page = response.meta["playwright_page"]
    title = await page.title()
    await page.context.close()  # close the context
    await page.close()
    return {"title": title}

async def close_context_on_error(self, failure):
    page = failure.request.meta["playwright_page"]
    await page.context.close()

Maximum concurrent context count

Specify a value for the PLAYWRIGHT_MAX_CONTEXTS setting to limit the amount of concurent contexts. This setting should be used with caution: it's possible to block the whole crawl if contexts are not closed after they are no longer used (refer to the above section to dinamically close contexts). Make sure to define an errback to still be able to close the context even if there are errors with a request.

Proxy support

Proxies are supported at the Browser level by specifying the proxy key in the PLAYWRIGHT_LAUNCH_OPTIONS setting:

from scrapy import Spider, Request

class ProxySpider(Spider):
    name = "proxy"
    custom_settings = {
        "PLAYWRIGHT_LAUNCH_OPTIONS": {
            "proxy": {
                "server": "http://myproxy.com:3128"
                "username": "user",
                "password": "pass",
            },
        }
    }

    def start_requests(self):
        yield Request("http://httpbin.org/get", meta={"playwright": True})

    def parse(self, response):
        print(response.text)

You can also set proxies per context with the PLAYWRIGHT_CONTEXTS setting:

PLAYWRIGHT_CONTEXTS = {
    "default": {
        "proxy": {
            "server": "http://default-proxy.com:3128",
            "username": "user1",
            "password": "pass1",
        },
    },
    "alternative": {
        "proxy": {
            "server": "http://alternative-proxy.com:3128",
            "username": "user2",
            "password": "pass2",
        },
    },
}

Or passing a proxy key when creating a context during a crawl.

See also the upstream Playwright section on HTTP Proxies.

Executing actions on pages

A sorted iterable (list, tuple or dict, for instance) could be passed in the playwright_page_methods Request.meta key to request coroutines to be awaited on the Page before returning the final Response to the callback.

This is useful when you need to perform certain actions on a page, like scrolling down or clicking links, and you want to handle only the final result in your callback.

PageMethod class

scrapy_playwright.page.PageMethod(method: str, *args, **kwargs):

Represents a method to be called (and awaited if necessary) on a playwright.page.Page object, such as "click", "screenshot", "evaluate", etc. method is the name of the method, *args and **kwargs are passed when calling such method. The return value will be stored in the PageMethod.result attribute.

For instance:

def start_requests(self):
    yield Request(
        url="https://example.org",
        meta={
            "playwright": True,
            "playwright_page_methods": [
                PageMethod("screenshot", path="example.png", fullPage=True),
            ],
        },
    )

def parse(self, response):
    screenshot = response.meta["playwright_page_methods"][0]
    # screenshot.result contains the image's bytes

produces the same effect as:

def start_requests(self):
    yield Request(
        url="https://example.org",
        meta={"playwright": True, "playwright_include_page": True},
    )

async def parse(self, response):
    page = response.meta["playwright_page"]
    screenshot = await page.screenshot(path="example.png", full_page=True)
    # screenshot contains the image's bytes
    await page.close()

Supported methods

Please refer to the upstream docs for the Page class to see available methods.

Impact on Response objects

Certain Response attributes (e.g. url, ip_address) reflect the state after the last action performed on a page. If you issue a PageMethod with an action that results in a navigation (e.g. a click on a link), the Response.url attribute will point to the new URL, which might be different from the request's URL.

Handling page events

A dictionary of Page event handlers can be specified in the playwright_page_event_handlers Request.meta key. Keys are the name of the event to be handled (dialog, download, etc). Values can be either callables or strings (in which case a spider method with the name will be looked up).

Example:

from playwright.async_api import Dialog

async def handle_dialog(dialog: Dialog) -> None:
    logging.info(f"Handled dialog with message: {dialog.message}")
    await dialog.dismiss()

class EventSpider(scrapy.Spider):
    name = "event"

    def start_requests(self):
        yield scrapy.Request(
            url="https://example.org",
            meta=dict(
                playwright=True,
                playwright_page_event_handlers={
                    "dialog": handle_dialog,
                    "response": "handle_response",
                },
            ),
        )

    async def handle_response(self, response: PlaywrightResponse) -> None:
        logging.info(f"Received response with URL {response.url}")

See the upstream Page docs for a list of the accepted events and the arguments passed to their handlers.

Note: keep in mind that, unless they are removed later, these handlers will remain attached to the page and will be called for subsequent downloads using the same page. This is usually not a problem, since by default requests are performed in single-use pages.

Examples

Click on a link, save the resulting page as PDF

class ClickAndSavePdfSpider(scrapy.Spider):
    name = "pdf"

    def start_requests(self):
        yield scrapy.Request(
            url="https://example.org",
            meta=dict(
                playwright=True,
                playwright_page_methods={
                    "click": PageMethod("click", selector="a"),
                    "pdf": PageMethod("pdf", path="/tmp/file.pdf"),
                },
            ),
        )

    def parse(self, response):
        pdf_bytes = response.meta["playwright_page_methods"]["pdf"].result
        with open("iana.pdf", "wb") as fp:
            fp.write(pdf_bytes)
        yield {"url": response.url}  # response.url is "https://www.iana.org/domains/reserved"

Scroll down on an infinite scroll page, take a screenshot of the full page

class ScrollSpider(scrapy.Spider):
    name = "scroll"

    def start_requests(self):
        yield scrapy.Request(
            url="http://quotes.toscrape.com/scroll",
            meta=dict(
                playwright=True,
                playwright_include_page=True,
                playwright_page_methods=[
                    PageMethod("wait_for_selector", "div.quote"),
                    PageMethod("evaluate", "window.scrollBy(0, document.body.scrollHeight)"),
                    PageMethod("wait_for_selector", "div.quote:nth-child(11)"),  # 10 per page
                ],
            ),
        )

    async def parse(self, response):
        page = response.meta["playwright_page"]
        await page.screenshot(path="quotes.png", fullPage=True)
        await page.close()
        return {"quote_count": len(response.css("div.quote"))}  # quotes from several pages

For more examples, please see the scripts in the examples directory.

Known limitations

• This package does not work out-of-the-box on Windows. See #7 (specifically this comment) for an explanation. Note that it seems to be possible to run under WSL.

  See also #78 for information about working in headful mode under WSL.

• Specifying a proxy via the proxy Request meta key is not supported. Refer to the Proxy support section for more information.

Deprecation policy

Deprecated features will be supported for at least six months following the release that deprecated them. After that, they may be removed at any time. See the changelog for more information about deprecations and removals.

Currently deprecated features

• scrapy_playwright.headers.use_playwright_headers function

  Deprecated since v0.0.16, set PLAYWRIGHT_PROCESS_REQUEST_HEADERS=None instead

• scrapy_playwright.page.PageCoroutine class

  Deprecated since v0.0.14, use scrapy_playwright.page.PageMethod instead

• playwright_page_coroutines Request meta key

  Deprecated since v0.0.14, use playwright_page_methods instead