The BrowserKit Component
The BrowserKit Component
The BrowserKit component simulates the behavior of a web browser, allowing you to make requests, click on links and submit forms programmatically.
Note
In Symfony versions prior to 4.3, the BrowserKit component could only make internal requests to your application. Starting from Symfony 4.3, this component can also make HTTP requests to any public site when using it in combination with the HttpClient component.
Installation
$ composer require symfony/browser-kit
Note
If you install this component outside of a Symfony application, you must require the vendor/autoload.php
file in your code to enable the class autoloading mechanism provided by Composer. Read this article for more details.
Basic Usage
See also
This article explains how to use the BrowserKit features as an independent component in any PHP application. Read the Symfony Functional Tests article to learn about how to use it in Symfony applications.
Creating a Client
The component only provides an abstract client and does not provide any backend ready to use for the HTTP layer. To create your own client, you must extend the AbstractBrowser
class and implement the doRequest() method. This method accepts a request and should return a response:
namespace Acme;
use Symfony\Component\BrowserKit\AbstractBrowser;
use Symfony\Component\BrowserKit\Response;
class Client extends AbstractBrowser
{
protected function doRequest($request)
{
// ... convert request into a response
return new Response($content, $status, $headers);
}
}
For a simple implementation of a browser based on the HTTP layer, have a look at the Symfony\Component\BrowserKit\HttpBrowser
provided by this component. For an implementation based on HttpKernelInterface
, have a look at the Symfony\Component\HttpKernel\Client
provided by the HttpKernel component.
Making Requests
Use the request() method to make HTTP requests. The first two arguments are the HTTP method and the requested URL:
use Acme\Client;
$client = new Client();
$crawler = $client->request('GET', '/');
The value returned by the request() method is an instance of the
Symfony\Component\DomCrawler\Crawler` class, provided by the DomCrawler component, which allows accessing and traversing HTML elements programmatically.
The jsonRequest() method, which defines the same arguments as the `request() method, is a shortcut to convert the request parameters into a JSON string and set the needed HTTP headers:
use Acme\Client;
$client = new Client();
// this encodes parameters as JSON and sets the required CONTENT_TYPE and HTTP_ACCEPT headers
$crawler = $client->jsonRequest('GET', '/', ['some_parameter' => 'some_value']);
New in version 5.3: The `jsonRequest() method was introduced in Symfony 5.3.
The xmlHttpRequest() method, which defines the same arguments as the `request() method, is a shortcut to make AJAX requests:
use Acme\Client;
$client = new Client();
// the required HTTP_X_REQUESTED_WITH header is added automatically
$crawler = $client->xmlHttpRequest('GET', '/');
Clicking Links
The AbstractBrowser
is capable of simulating link clicks. Pass the text content of the link and the client will perform the needed HTTP GET request to simulate the link click:
use Acme\Client;
$client = new Client();
$client->request('GET', '/product/123');
$crawler = $client->clickLink('Go elsewhere...');
If you need the Symfony\Component\DomCrawler\Link
object that provides access to the link properties (e.g. $link->getMethod(),
$link->getUri()), use this other method:
// ...
$crawler = $client->request('GET', '/product/123');
$link = $crawler->selectLink('Go elsewhere...')->link();
$client->click($link);
Submitting Forms
The AbstractBrowser
is also capable of submitting forms. First, select the form using any of its buttons and then override any of its properties (method, field values, etc.) before submitting it:
use Acme\Client;
$client = new Client();
$crawler = $client->request('GET', 'https://github.com/login');
// find the form with the 'Log in' button and submit it
// 'Log in' can be the text content, id, value or name of a <button> or <input type="submit">
$client->submitForm('Log in');
// the second optional argument lets you override the default form field values
$client->submitForm('Log in', [
'login' => 'my_user',
'password' => 'my_pass',
// to upload a file, the value must be the absolute file path
'file' => __FILE__,
]);
// you can override other form options too
$client->submitForm(
'Log in',
['login' => 'my_user', 'password' => 'my_pass'],
// override the default form HTTP method
'PUT',
// override some $_SERVER parameters (e.g. HTTP headers)
['HTTP_ACCEPT_LANGUAGE' => 'es']
);
If you need the Symfony\Component\DomCrawler\Form
object that provides access to the form properties (e.g. $form->getUri(),
$form->getValues(), `$form->getFields()), use this other method:
// ...
// select the form and fill in some values
$form = $crawler->selectButton('Log in')->form();
$form['login'] = 'symfonyfan';
$form['password'] = 'anypass';
// submit that form
$crawler = $client->submit($form);
Custom Header Handling
New in version 5.2: The `getHeaders() method was introduced in Symfony 5.2.
The optional HTTP headers passed to the request() method follows the FastCGI request format (uppercase, underscores instead of dashes and prefixed with
HTTP). Before saving those headers to the request, they are lower-cased, with
HTTP` stripped, and underscores turned to dashes.
If you’re making a request to an application that has special rules about header capitalization or punctuation, override the `getHeaders() method, which must return an associative array of headers:
protected function getHeaders(Request $request): array
{
$headers = parent::getHeaders($request);
if (isset($request->getServer()['api_key'])) {
$headers['api_key'] = $request->getServer()['api_key'];
}
return $headers;
}
Cookies
Retrieving Cookies
The AbstractBrowser
implementation exposes cookies (if any) through a Symfony\Component\BrowserKit\CookieJar
, which allows you to store and retrieve any cookie while making requests with the client:
use Acme\Client;
// Make a request
$client = new Client();
$crawler = $client->request('GET', '/');
// Get the cookie Jar
$cookieJar = $client->getCookieJar();
// Get a cookie by name
$cookie = $cookieJar->get('name_of_the_cookie');
// Get cookie data
$name = $cookie->getName();
$value = $cookie->getValue();
$rawValue = $cookie->getRawValue();
$isSecure = $cookie->isSecure();
$isHttpOnly = $cookie->isHttpOnly();
$isExpired = $cookie->isExpired();
$expires = $cookie->getExpiresTime();
$path = $cookie->getPath();
$domain = $cookie->getDomain();
$sameSite = $cookie->getSameSite();
Note
These methods only return cookies that have not expired.
Looping Through Cookies
use Acme\Client;
// Make a request
$client = new Client();
$crawler = $client->request('GET', '/');
// Get the cookie Jar
$cookieJar = $client->getCookieJar();
// Get array with all cookies
$cookies = $cookieJar->all();
foreach ($cookies as $cookie) {
// ...
}
// Get all values
$values = $cookieJar->allValues('http://symfony.com');
foreach ($values as $value) {
// ...
}
// Get all raw values
$rawValues = $cookieJar->allRawValues('http://symfony.com');
foreach ($rawValues as $rawValue) {
// ...
}
Setting Cookies
You can also create cookies and add them to a cookie jar that can be injected into the client constructor:
use Acme\Client;
// create cookies and add to cookie jar
$cookie = new Cookie('flavor', 'chocolate', strtotime('+1 day'));
$cookieJar = new CookieJar();
$cookieJar->set($cookie);
// create a client and set the cookies
$client = new Client([], null, $cookieJar);
// ...
History
The client stores all your requests allowing you to go back and forward in your history:
use Acme\Client;
$client = new Client();
$client->request('GET', '/');
// select and click on a link
$link = $crawler->selectLink('Documentation')->link();
$client->click($link);
// go back to home page
$crawler = $client->back();
// go forward to documentation page
$crawler = $client->forward();
You can delete the client’s history with the `restart() method. This will also delete all the cookies:
use Acme\Client;
$client = new Client();
$client->request('GET', '/');
// reset the client (history and cookies are cleared too)
$client->restart();
Making External HTTP Requests
So far, all the examples in this article have assumed that you are making internal requests to your own application. However, you can run the exact same examples when making HTTP requests to external web sites and applications.
First, install and configure the HttpClient component. Then, use the Symfony\Component\BrowserKit\HttpBrowser
to create the client that will make the external HTTP requests:
use Symfony\Component\BrowserKit\HttpBrowser;
use Symfony\Component\HttpClient\HttpClient;
$browser = new HttpBrowser(HttpClient::create());
You can now use any of the methods shown in this article to extract information, click links, submit forms, etc. This means that you no longer need to use a dedicated web crawler or scraper such as Goutte:
$browser = new HttpBrowser(HttpClient::create());
$browser->request('GET', 'https://github.com');
$browser->clickLink('Sign in');
$browser->submitForm('Sign in', ['login' => '...', 'password' => '...']);
$openPullRequests = trim($browser->clickLink('Pull requests')->filter(
'.table-list-header-toggle a:nth-child(1)'
)->text());
Learn more
This work, including the code samples, is licensed under a Creative Commons BY-SA 3.0 license.