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Version: 1.22

BrowserContext

BrowserContexts provide a way to operate multiple independent browser sessions.

If a page opens another page, e.g. with a window.open call, the popup will belong to the parent page's browser context.

Playwright allows creating "incognito" browser contexts with browser.new_context(**kwargs) method. "Incognito" browser contexts don't write any browsing data to disk.

# create a new incognito browser context
context = browser.new_context()
# create a new page inside context.
page = context.new_page()
page.goto("https://example.com")
# dispose context once it is no longer needed.
context.close()

browser_context.on("backgroundpage")

note

Only works with Chromium browser's persistent context.

Emitted when new background page is created in the context.

background_page = context.wait_for_event("backgroundpage")

browser_context.on("close")

Emitted when Browser context gets closed. This might happen because of one of the following:

  • Browser context is closed.
  • Browser application is closed or crashed.
  • The browser.close() method was called.

browser_context.on("page")

The event is emitted when a new Page is created in the BrowserContext. The page may still be loading. The event will also fire for popup pages. See also page.on("popup") to receive events about popups relevant to a specific page.

The earliest moment that page is available is when it has navigated to the initial url. For example, when opening a popup with window.open('http://example.com'), this event will fire when the network request to "http://example.com" is done and its response has started loading in the popup.

with context.expect_page() as page_info:
page.click("a[target=_blank]"),
page = page_info.value
print(page.evaluate("location.href"))
note

Use page.wait_for_load_state(**kwargs) to wait until the page gets to a particular state (you should not need it in most cases).

browser_context.on("request")

Emitted when a request is issued from any pages created through this context. The request object is read-only. To only listen for requests from a particular page, use page.on("request").

In order to intercept and mutate requests, see browser_context.route(url, handler, **kwargs) or page.route(url, handler, **kwargs).

browser_context.on("requestfailed")

Emitted when a request fails, for example by timing out. To only listen for failed requests from a particular page, use page.on("requestfailed").

note

HTTP Error responses, such as 404 or 503, are still successful responses from HTTP standpoint, so request will complete with browser_context.on("requestfinished") event and not with browser_context.on("requestfailed").

browser_context.on("requestfinished")

Emitted when a request finishes successfully after downloading the response body. For a successful response, the sequence of events is request, response and requestfinished. To listen for successful requests from a particular page, use page.on("requestfinished").

browser_context.on("response")

Emitted when response status and headers are received for a request. For a successful response, the sequence of events is request, response and requestfinished. To listen for response events from a particular page, use page.on("response").

browser_context.on("serviceworker")

note

Service workers are only supported on Chromium-based browsers.

Emitted when new service worker is created in the context.

browser_context.add_cookies(cookies)

  • cookies <List[Dict]>#
    • name <str>
    • value <str>
    • url <str> either url or domain / path are required. Optional.
    • domain <str> either url or domain / path are required Optional.
    • path <str> either url or domain / path are required Optional.
    • expires <float> Unix time in seconds. Optional.
    • httpOnly <bool> Optional.
    • secure <bool> Optional.
    • sameSite <"Strict"|"Lax"|"None"> Optional.
  • returns: <NoneType>#

Adds cookies into this browser context. All pages within this context will have these cookies installed. Cookies can be obtained via browser_context.cookies(**kwargs).

browser_context.add_cookies([cookie_object1, cookie_object2])

browser_context.add_init_script(**kwargs)

  • path <Union[str, pathlib.Path]> Path to the JavaScript file. If path is a relative path, then it is resolved relative to the current working directory. Optional.#
  • script <str> Script to be evaluated in all pages in the browser context. Optional.#
  • returns: <NoneType>#

Adds a script which would be evaluated in one of the following scenarios:

  • Whenever a page is created in the browser context or is navigated.
  • Whenever a child frame is attached or navigated in any page in the browser context. In this case, the script is evaluated in the context of the newly attached frame.

The script is evaluated after the document was created but before any of its scripts were run. This is useful to amend the JavaScript environment, e.g. to seed Math.random.

An example of overriding Math.random before the page loads:

// preload.js
Math.random = () => 42;
# in your playwright script, assuming the preload.js file is in same directory.
browser_context.add_init_script(path="preload.js")
note

The order of evaluation of multiple scripts installed via browser_context.add_init_script(**kwargs) and page.add_init_script(**kwargs) is not defined.

browser_context.background_pages

note

Background pages are only supported on Chromium-based browsers.

All existing background pages in the context.

browser_context.browser

Returns the browser instance of the context. If it was launched as a persistent context null gets returned.

browser_context.clear_cookies()

Clears context cookies.

browser_context.clear_permissions()

Clears all permission overrides for the browser context.

context = browser.new_context()
context.grant_permissions(["clipboard-read"])
# do stuff ..
context.clear_permissions()

browser_context.close()

Closes the browser context. All the pages that belong to the browser context will be closed.

note

The default browser context cannot be closed.

browser_context.cookies(**kwargs)

If no URLs are specified, this method returns all cookies. If URLs are specified, only cookies that affect those URLs are returned.

browser_context.expect_event(event, **kwargs)

  • event <str> Event name, same one would pass into browserContext.on(event).#
  • predicate <Callable> Receives the event data and resolves to truthy value when the waiting should resolve.#
  • timeout <float> Maximum time to wait for in milliseconds. Defaults to 30000 (30 seconds). Pass 0 to disable timeout. The default value can be changed by using the browser_context.set_default_timeout(timeout).#
  • returns: <EventContextManager>#

Waits for event to fire and passes its value into the predicate function. Returns when the predicate returns truthy value. Will throw an error if the context closes before the event is fired. Returns the event data value.

with context.expect_event("page") as event_info:
page.click("button")
page = event_info.value

browser_context.expect_page(**kwargs)

Performs action and waits for a new Page to be created in the context. If predicate is provided, it passes Page value into the predicate function and waits for predicate(event) to return a truthy value. Will throw an error if the context closes before new Page is created.

browser_context.expose_binding(name, callback, **kwargs)

  • name <str> Name of the function on the window object.#
  • callback <Callable> Callback function that will be called in the Playwright's context.#
  • handle <bool> Whether to pass the argument as a handle, instead of passing by value. When passing a handle, only one argument is supported. When passing by value, multiple arguments are supported.#
  • returns: <NoneType>#

The method adds a function called name on the window object of every frame in every page in the context. When called, the function executes callback and returns a Promise which resolves to the return value of callback. If the callback returns a Promise, it will be awaited.

The first argument of the callback function contains information about the caller: { browserContext: BrowserContext, page: Page, frame: Frame }.

See page.expose_binding(name, callback, **kwargs) for page-only version.

An example of exposing page URL to all frames in all pages in the context:

from playwright.sync_api import sync_playwright

def run(playwright):
webkit = playwright.webkit
browser = webkit.launch(headless=false)
context = browser.new_context()
context.expose_binding("pageURL", lambda source: source["page"].url)
page = context.new_page()
page.set_content("""
<script>
async function onClick() {
document.querySelector('div').textContent = await window.pageURL();
}
</script>
<button onclick="onClick()">Click me</button>
<div></div>
""")
page.click("button")

with sync_playwright() as playwright:
run(playwright)

An example of passing an element handle:

def print(source, element):
print(element.text_content())

context.expose_binding("clicked", print, handle=true)
page.set_content("""
<script>
document.addEventListener('click', event => window.clicked(event.target));
</script>
<div>Click me</div>
<div>Or click me</div>
""")

browser_context.expose_function(name, callback)

  • name <str> Name of the function on the window object.#
  • callback <Callable> Callback function that will be called in the Playwright's context.#
  • returns: <NoneType>#

The method adds a function called name on the window object of every frame in every page in the context. When called, the function executes callback and returns a Promise which resolves to the return value of callback.

If the callback returns a Promise, it will be awaited.

See page.expose_function(name, callback) for page-only version.

An example of adding a sha256 function to all pages in the context:

import hashlib
from playwright.sync_api import sync_playwright

def sha256(text):
m = hashlib.sha256()
m.update(bytes(text, "utf8"))
return m.hexdigest()


def run(playwright):
webkit = playwright.webkit
browser = webkit.launch(headless=False)
context = browser.new_context()
context.expose_function("sha256", sha256)
page = context.new_page()
page.set_content("""
<script>
async function onClick() {
document.querySelector('div').textContent = await window.sha256('PLAYWRIGHT');
}
</script>
<button onclick="onClick()">Click me</button>
<div></div>
""")
page.click("button")

with sync_playwright() as playwright:
run(playwright)

browser_context.grant_permissions(permissions, **kwargs)

  • permissions <List[str]> A permission or an array of permissions to grant. Permissions can be one of the following values:#
    • 'geolocation'
    • 'midi'
    • 'midi-sysex' (system-exclusive midi)
    • 'notifications'
    • 'camera'
    • 'microphone'
    • 'background-sync'
    • 'ambient-light-sensor'
    • 'accelerometer'
    • 'gyroscope'
    • 'magnetometer'
    • 'accessibility-events'
    • 'clipboard-read'
    • 'clipboard-write'
    • 'payment-handler'
  • origin <str> The origin to grant permissions to, e.g. "https://example.com".#
  • returns: <NoneType>#

Grants specified permissions to the browser context. Only grants corresponding permissions to the given origin if specified.

browser_context.new_cdp_session(page)

  • page <Page|Frame> Target to create new session for. For backwards-compatibility, this parameter is named page, but it can be a Page or Frame type.#
  • returns: <CDPSession>#
note

CDP sessions are only supported on Chromium-based browsers.

Returns the newly created session.

browser_context.new_page()

Creates a new page in the browser context.

browser_context.pages

Returns all open pages in the context.

browser_context.route(url, handler, **kwargs)

  • url <str|Pattern|Callable[URL]:bool> A glob pattern, regex pattern or predicate receiving URL to match while routing. When a base_url via the context options was provided and the passed URL is a path, it gets merged via the new URL() constructor.#
  • handler <Callable[Route, Request]> handler function to route the request.#
  • times <int> How often a route should be used. By default it will be used every time.#
  • returns: <NoneType>#

Routing provides the capability to modify network requests that are made by any page in the browser context. Once route is enabled, every request matching the url pattern will stall unless it's continued, fulfilled or aborted.

note

page.route(url, handler, **kwargs) will not intercept requests intercepted by Service Worker. See this issue. We recommend disabling Service Workers when using request interception. Via await context.addInitScript(() => delete window.navigator.serviceWorker);

An example of a naive handler that aborts all image requests:

context = browser.new_context()
page = context.new_page()
context.route("**/*.{png,jpg,jpeg}", lambda route: route.abort())
page.goto("https://example.com")
browser.close()

or the same snippet using a regex pattern instead:

context = browser.new_context()
page = context.new_page()
context.route(re.compile(r"(\.png$)|(\.jpg$)"), lambda route: route.abort())
page = await context.new_page()
page = context.new_page()
page.goto("https://example.com")
browser.close()

It is possible to examine the request to decide the route action. For example, mocking all requests that contain some post data, and leaving all other requests as is:

def handle_route(route):
if ("my-string" in route.request.post_data)
route.fulfill(body="mocked-data")
else
route.continue_()
context.route("/api/**", handle_route)

Page routes (set up with page.route(url, handler, **kwargs)) take precedence over browser context routes when request matches both handlers.

To remove a route with its handler you can use browser_context.unroute(url, **kwargs).

note

Enabling routing disables http cache.

browser_context.service_workers

note

Service workers are only supported on Chromium-based browsers.

All existing service workers in the context.

browser_context.set_default_navigation_timeout(timeout)

  • timeout <float> Maximum navigation time in milliseconds#
  • returns: <NoneType>#

This setting will change the default maximum navigation time for the following methods and related shortcuts:

browser_context.set_default_timeout(timeout)

This setting will change the default maximum time for all the methods accepting timeout option.

browser_context.set_extra_http_headers(headers)

  • headers <Dict[str, str]> An object containing additional HTTP headers to be sent with every request. All header values must be strings.#
  • returns: <NoneType>#

The extra HTTP headers will be sent with every request initiated by any page in the context. These headers are merged with page-specific extra HTTP headers set with page.set_extra_http_headers(headers). If page overrides a particular header, page-specific header value will be used instead of the browser context header value.

note

browser_context.set_extra_http_headers(headers) does not guarantee the order of headers in the outgoing requests.

browser_context.set_geolocation(geolocation)

  • geolocation <NoneType|Dict>#
    • latitude <float> Latitude between -90 and 90.
    • longitude <float> Longitude between -180 and 180.
    • accuracy <float> Non-negative accuracy value. Defaults to 0.
  • returns: <NoneType>#

Sets the context's geolocation. Passing null or undefined emulates position unavailable.

browser_context.set_geolocation({"latitude": 59.95, "longitude": 30.31667})
note

Consider using browser_context.grant_permissions(permissions, **kwargs) to grant permissions for the browser context pages to read its geolocation.

browser_context.set_offline(offline)

  • offline <bool> Whether to emulate network being offline for the browser context.#
  • returns: <NoneType>#

browser_context.storage_state(**kwargs)

  • path <Union[str, pathlib.Path]> The file path to save the storage state to. If path is a relative path, then it is resolved relative to current working directory. If no path is provided, storage state is still returned, but won't be saved to the disk.#
  • returns: <Dict>#

Returns storage state for this browser context, contains current cookies and local storage snapshot.

browser_context.unroute(url, **kwargs)

Removes a route created with browser_context.route(url, handler, **kwargs). When handler is not specified, removes all routes for the url.

browser_context.wait_for_event(event, **kwargs)

  • event <str> Event name, same one typically passed into *.on(event).#
  • predicate <Callable> Receives the event data and resolves to truthy value when the waiting should resolve.#
  • timeout <float> Maximum time to wait for in milliseconds. Defaults to 30000 (30 seconds). Pass 0 to disable timeout. The default value can be changed by using the browser_context.set_default_timeout(timeout).#
  • returns: <Any>#
note

In most cases, you should use browser_context.expect_event(event, **kwargs).

Waits for given event to fire. If predicate is provided, it passes event's value into the predicate function and waits for predicate(event) to return a truthy value. Will throw an error if the browser context is closed before the event is fired.

browser_context.request

API testing helper associated with this context. Requests made with this API will use context cookies.

browser_context.tracing