A browser testing and web scraping library for PHP and Symfony

Panther is a convenient standalone library to scrape websites and to run end-to-end tests using real browsers.

Panther is super powerful. It leverages the W3C's WebDriver protocol to drive native web browsers such as Google Chrome and Firefox.

Panther is very easy to use, because it implements Symfony's popular BrowserKit and DomCrawler APIs, and contains all the features you need to test your apps. It will sound familiar if you have ever created a functional test for a Symfony app: as the API is exactly the same! Keep in mind that Panther can be used in every PHP project, as it is a standalone library.

Panther automatically finds your local installation of Chrome or Firefox and launches them, so you don't need to install anything else on your computer, a Selenium server is not needed!

In test mode, Panther automatically starts your application using the PHP built-in web-server. You can focus on writing your tests or web-scraping scenario and Panther will take care of everything else.

Features

Unlike testing and web scraping libraries you're used to, Panther:

• executes the JavaScript code contained in webpages
• supports everything that Chrome (or Firefox) implements
• allows taking screenshots
• can wait for asynchronously loaded elements to show up
• lets you run your own JS code or XPath queries in the context of the loaded page
• supports custom Selenium server installations
• supports remote browser testing services including SauceLabs and BrowserStack

Documentation

Installing Panther

Use Composer to install Panther in your project. You may want to use the --dev flag if you want to use Panther for testing only and not for web scraping in a production environment:

composer req symfony/panther

composer req --dev symfony/panther

Installing ChromeDriver and geckodriver

Panther uses the WebDriver protocol to control the browser used to crawl websites.

On all systems, you can use dbrekelmans/browser-driver-installer to install ChromeDriver and geckodriver locally:

composer require --dev dbrekelmans/bdi
vendor/bin/bdi detect drivers

Panther will detect and use automatically drivers stored in the drivers/ directory.

Alternatively, you can use the package manager of your operating system to install them.

On Ubuntu, run:

apt-get install chromium-chromedriver firefox-geckodriver

On Mac, using Homebrew:

brew install chromedriver geckodriver

On Windows, using chocolatey:

choco install chromedriver selenium-gecko-driver

Finally, you can download manually ChromeDriver (for Chromium or Chrome) and GeckoDriver (for Firefox) and put them anywhere in your PATH or in the drivers/ directory of your project.

Registering the PHPUnit Extension

If you intend to use Panther to test your application, we strongly recommend registering the Panther PHPUnit extension. While not strictly mandatory, this extension dramatically improves the testing experience by boosting the performance and allowing to use the interactive debugging mode.

When using the extension in conjunction with the PANTHER_ERROR_SCREENSHOT_DIR environment variable, tests using the Panther client that fail or error (after the client is created) will automatically get a screenshot taken to help debugging.

To register the Panther extension, add the following lines to phpunit.xml.dist:

<!-- phpunit.xml.dist -->
<extensions>
    <extension class="Symfony\Component\Panther\ServerExtension" />
</extensions>

Without the extension, the web server used by Panther to serve the application under test is started on demand and stopped when tearDownAfterClass() is called. On the other hand, when the extension is registered, the web server will be stopped only after the very last test.

Basic Usage

<?php

use Symfony\Component\Panther\Client;

require __DIR__.'/vendor/autoload.php'; // Composer's autoloader

$client = Client::createChromeClient();
// Or, if you care about the open web and prefer to use Firefox
$client = Client::createFirefoxClient();

$client->request('GET', 'https://api-platform.com'); // Yes, this website is 100% written in JavaScript
$client->clickLink('Get started');

// Wait for an element to be present in the DOM (even if hidden)
$crawler = $client->waitFor('#installing-the-framework');
// Alternatively, wait for an element to be visible
$crawler = $client->waitForVisibility('#installing-the-framework');

echo $crawler->filter('#installing-the-framework')->text();
$client->takeScreenshot('screen.png'); // Yeah, screenshot!

Testing Usage

The PantherTestCase class allows you to easily write E2E tests. It automatically starts your app using the built-in PHP web server and let you crawl it using Panther. To provide all the testing tools you're used to, it extends PHPUnit's TestCase.

If you are testing a Symfony application, PantherTestCase automatically extends the WebTestCase class. It means you can easily create functional tests, which can directly execute the kernel of your application and access all your existing services. In this case, you can use all crawler test assertions provided by Symfony with Panther.

<?php

namespace App\Tests;

use Symfony\Component\Panther\PantherTestCase;

class E2eTest extends PantherTestCase
{
    public function testMyApp(): void
    {
        $client = static::createPantherClient(); // Your app is automatically started using the built-in web server
        $client->request('GET', '/mypage');

        // Use any PHPUnit assertion, including the ones provided by Symfony
        $this->assertPageTitleContains('My Title');
        $this->assertSelectorTextContains('#main', 'My body');
        
        // Or the one provided by Panther
        $this->assertSelectorIsEnabled('.search');
        $this->assertSelectorIsDisabled('[type="submit"]');
        $this->assertSelectorIsVisible('.errors');
        $this->assertSelectorIsNotVisible('.loading');
        $this->assertSelectorAttributeContains('.price', 'data-old-price', '42');
        $this->assertSelectorAttributeNotContains('.price', 'data-old-price', '36');

        // Use waitForX methods to wait until some asynchronous process finish
        $client->waitFor('.popin'); // wait for element to be attached to the DOM
        $client->waitForStaleness('.popin'); // wait for element to be removed from the DOM
        $client->waitForVisibility('.loader'); // wait for element of the DOM to become visible
        $client->waitForInvisibility('.loader'); // wait for element of the DOM to become hidden
        $client->waitForElementToContain('.total', '25 €'); // wait for text to be inserted in the element content
        $client->waitForElementToNotContain('.promotion', '5%'); // wait for text to be removed from the element content
        $client->waitForEnabled('[type="submit"]'); // wait for the button to become enabled 
        $client->waitForDisabled('[type="submit"]'); // wait for  the button to become disabled 
        $client->waitForAttributeToContain('.price', 'data-old-price', '25 €'); // wait for the attribute to contain content
        $client->waitForAttributeToNotContain('.price', 'data-old-price', '25 €'); // wait for the attribute to not contain content
        
        // Let's predict the future
        $this->assertSelectorWillExist('.popin'); // element will be attached to the DOM
        $this->assertSelectorWillNotExist('.popin'); // element will be removed from the DOM
        $this->assertSelectorWillBeVisible('.loader'); // element will be visible
        $this->assertSelectorWillNotBeVisible('.loader'); // element will not be visible
        $this->assertSelectorWillContain('.total', '€25'); // text will be inserted in the element content
        $this->assertSelectorWillNotContain('.promotion', '5%'); // text will be removed from the element content
        $this->assertSelectorWillBeEnabled('[type="submit"]'); // button will be enabled 
        $this->assertSelectorWillBeDisabled('[type="submit"]'); // button will be disabled 
        $this->assertSelectorAttributeWillContain('.price', 'data-old-price', '€25'); // attribute will contain content
        $this->assertSelectorAttributeWillNotContain('.price', 'data-old-price', '€25'); // attribute will not contain content
    }
}

To run this test:

bin/phpunit tests/E2eTest.php

A Polymorphic Feline

Panther also gives you instant access to other BrowserKit-based implementations of Client and Crawler. Unlike Panther's native client, these alternative clients don't support JavaScript, CSS and screenshot capturing, but they are super-fast!

Two alternative clients are available:

• The first directly manipulates the Symfony kernel provided by WebTestCase. It is the fastest client available, but it is only available for Symfony apps.
• The second leverages Symfony's HttpBrowser. It is an intermediate between Symfony's kernel and Panther's test clients. HttpBrowser sends real HTTP requests using Symfony's HttpClient component. It is fast and is able to browse any webpage, not only the ones of the application under test. However, HttpBrowser doesn't support JavaScript and other advanced features because it is entirely written in PHP. This one is available even for non-Symfony apps!

The fun part is that the 3 clients implement the exact same API, so you can switch from one to another just by calling the appropriate factory method, resulting in a good trade-off for every single test case (Do I need JavaScript? Do I need to authenticate with an external SSO server? Do I want to access the kernel of the current request? ... etc).

Here is how to retrieve instances of these clients:

<?php

namespace App\Tests;

use Symfony\Component\Panther\PantherTestCase;
use Symfony\Component\Panther\Client;

class E2eTest extends PantherTestCase
{
    public function testMyApp(): void
    {
        $symfonyClient = static::createClient(); // A cute kitty: Symfony's functional test tool
        $httpBrowserClient = static::createHttpBrowserClient(); // An agile lynx: HttpBrowser
        $pantherClient = static::createPantherClient(); // A majestic Panther
        $firefoxClient = static::createPantherClient(['browser' => static::FIREFOX]); // A splendid Firefox
        // Both HttpBrowser and Panther benefits from the built-in HTTP server

        $customChromeClient = Client::createChromeClient(null, null, [], 'https://example.com'); // Create a custom Chrome client
        $customFirefoxClient = Client::createFirefoxClient(null, null, [], 'https://example.com'); // Create a custom Firefox client
        $customSeleniumClient = Client::createSeleniumClient('http://127.0.0.1:4444/wd/hub', null, 'https://example.com'); // Create a custom Selenium client
        // When initializing a custom client, the integrated web server IS NOT started automatically.
        // Use PantherTestCase::startWebServer() or WebServerManager if you want to start it manually.

        // enjoy the same API for the 3 felines
        // $*client->request('GET', '...')

        $kernel = static::createKernel(); // If you are testing a Symfony app, you also have access to the kernel

        // ...
    }
}

Creating Isolated Browsers to Test Apps Using Mercure or WebSocket

Panther provides a convenient way to test applications with real-time capabilities which use Mercure, WebSocket and similar technologies.

PantherTestCase::createAdditionalPantherClient() creates additional, isolated browsers which can interact with each other. For instance, this can be useful to test a chat application having several users connected simultaneously:

<?php

use Symfony\Component\Panther\PantherTestCase;

class ChatTest extends PantherTestCase
{
    public function testChat(): void
    {
        $client1 = self::createPantherClient();
        $client1->request('GET', '/chat'); 
 
        // Connect a 2nd user using an isolated browser and say hi!
        $client2 = self::createAdditionalPantherClient();
        $client2->request('GET', '/chat');
        $client2->submitForm('Post message', ['message' => 'Hi folks 👋😻']);

        // Wait for the message to be received by the first client
        $client1->waitFor('.message');

        // Symfony Assertions are always executed in the **primary** browser
        $this->assertSelectorTextContains('.message', 'Hi folks 👋😻');
    }
}

Accessing Browser Console Logs

If needed, you can use Panther to access the content of the console:

<?php

use Symfony\Component\Panther\PantherTestCase;

class ConsoleTest extends PantherTestCase
{
    public function testConsole(): void
    {
        $client = self::createPantherClient(
            [],
            [],
            [
                'capabilities' => [
                    'goog:loggingPrefs' => [
                        'browser' => 'ALL', // calls to console.* methods
                        'performance' => 'ALL', // performance data
                    ],
                ],
            ]
        );

        $client->request('GET', '/');
        $consoleLogs = $client->getWebDriver()->manage()->getLog('browser'); // console logs 
        $performanceLogs = $client->getWebDriver()->manage()->getLog('performance'); // performance logs
    }
}

Passing Arguments to ChromeDriver

If needed, you can configure the arguments to pass to the chromedriver binary:

<?php

use Symfony\Component\Panther\PantherTestCase;

class MyTest extends PantherTestCase
{
    public function testLogging(): void
    {
        $client = self::createPantherClient(
            [],
            [],
            [
                'chromedriver_arguments' => [
                    '--log-path=myfile.log',
                    '--log-level=DEBUG'
                ],
            ]
        );

        $client->request('GET', '/');
    }
}

Checking the State of the WebDriver Connection

Use the Client::ping() method to check if the WebDriver connection is still active (useful for long-running tasks).

Additional Documentation

Since Panther implements the API of popular libraries, it already has an extensive documentation:

• For the Client class, read the BrowserKit documentation
• For the Crawler class, read the DomCrawler documentation
• For WebDriver, read the PHP WebDriver documentation

Environment Variables

The following environment variables can be set to change some Panther's behaviour:

• PANTHER_NO_HEADLESS: to disable the browser's headless mode (will display the testing window, useful to debug)
• PANTHER_WEB_SERVER_DIR: to change the project's document root (default to ./public/, relative paths must start by ./)
• PANTHER_WEB_SERVER_PORT: to change the web server's port (default to 9080)
• PANTHER_WEB_SERVER_ROUTER: to use a web server router script which is run at the start of each HTTP request
• PANTHER_EXTERNAL_BASE_URI: to use an external web server (the PHP built-in web server will not be started)
• PANTHER_APP_ENV: to override the APP_ENV variable passed to the web server running the PHP app
• PANTHER_ERROR_SCREENSHOT_DIR: to set a base directory for your failure/error screenshots (e.g. ./var/error-screenshots)
• PANTHER_DEVTOOLS: to toggle the browser's dev tools (default enabled, useful to debug)
• PANTHER_ERROR_SCREENSHOT_ATTACH: to add screenshots mentioned above to test output in junit attachment format

Changing the Hostname and Port of the Built-in Web Server

If you want to change the host and/or the port used by the built-in web server, pass the hostname and port to the $options parameter of the createPantherClient() method:

// ...

$client = self::createPantherClient([
    'hostname' => 'example.com', // Defaults to 127.0.0.1
    'port' => 8080, // Defaults to 9080
]);

Chrome-specific Environment Variables

• PANTHER_NO_SANDBOX: to disable Chrome's sandboxing (unsafe, but allows to use Panther in containers)
• PANTHER_CHROME_ARGUMENTS: to customize Chrome arguments. You need to set PANTHER_NO_HEADLESS to fully customize.
• PANTHER_CHROME_BINARY: to use another google-chrome binary

Firefox-specific Environment Variables

• PANTHER_FIREFOX_ARGUMENTS: to customize Firefox arguments. You need to set PANTHER_NO_HEADLESS to fully customize.
• PANTHER_FIREFOX_BINARY: to use another firefox binary

Accessing To Hidden Text

According to the spec, WebDriver implementations return only the displayed text by default. When you filter on a head tag (like title), the method text() returns an empty string. Use the method html() to get the complete contents of the tag, including the tag itself.

Interactive Mode

Panther can make a pause in your tests suites after a failure. It is a break time really appreciated for investigating the problem through the web browser. For enabling this mode, you need the --debug PHPUnit option without the headless mode:

$ PANTHER_NO_HEADLESS=1 bin/phpunit --debug

Test 'App\AdminTest::testLogin' started
Error: something is wrong.

Press enter to continue...

To use the interactive mode, the PHPUnit extension must be registered.

Using an External Web Server

Sometimes, it's convenient to reuse an existing web server configuration instead of starting the built-in PHP one. To do so, set the external_base_uri option:

<?php

namespace App\Tests;

use Symfony\Component\Panther\PantherTestCase;

class E2eTest extends PantherTestCase
{
    public function testMyApp(): void
    {
        $pantherClient = static::createPantherClient(['external_base_uri' => 'https://localhost']);
        // the PHP integrated web server will not be started
    }
}

Having a Multi-domain Application

It happens that your PHP/Symfony application might serve several different domain names.

As Panther saves the Client in memory between tests to improve performances, you will have to run your tests in separate processes if you write several tests using Panther for different domain names.

To do so, you can use the native @runInSeparateProcess PHPUnit annotation.

ℹ Note: it is really convenient to use the external_base_uri option and start your own webserver in the background, because Panther will not have to start and stop your server on each test. Symfony CLI can be a quick and easy way to do so.

Here is an example using the external_base_uri option to determine the domain name used by the Client:

<?php

namespace App\Tests;

use Symfony\Component\Panther\PantherTestCase;

class FirstDomainTest extends PantherTestCase
{
    /**
     * @runInSeparateProcess
     */
    public function testMyApp(): void
    {
        $pantherClient = static::createPantherClient([
            'external_base_uri' => 'http://mydomain.localhost:8000',
        ]);
        
        // Your tests
    }
}

<?php

namespace App\Tests;

use Symfony\Component\Panther\PantherTestCase;

class SecondDomainTest extends PantherTestCase
{
    /**
     * @runInSeparateProcess
     */
    public function testMyApp(): void
    {
        $pantherClient = static::createPantherClient([
            'external_base_uri' => 'http://anotherdomain.localhost:8000',
        ]);
        
        // Your tests
    }
}

Using a Proxy

To use a proxy server, set the following environment variable: PANTHER_CHROME_ARGUMENTS='--proxy-server=socks://127.0.0.1:9050'

Accepting Self-signed SSL Certificates

To force Chrome to accept invalid and self-signed certificates, set the following environment variable: PANTHER_CHROME_ARGUMENTS='--ignore-certificate-errors' This option is insecure, use it only for testing in development environments, never in production (e.g. for web crawlers).

For Firefox, instantiate the client like this:

$client = Client::createFirefoxClient(null, null, ['capabilities' => ['acceptInsecureCerts' => true]]);

Docker Integration

Here is a minimal Docker image that can run Panther with both Chrome and Firefox:

FROM php:alpine

# Chromium and ChromeDriver
ENV PANTHER_NO_SANDBOX 1
# Not mandatory, but recommended
ENV PANTHER_CHROME_ARGUMENTS='--disable-dev-shm-usage'
RUN apk add --no-cache chromium chromium-chromedriver

# Firefox and GeckoDriver (optional)
ARG GECKODRIVER_VERSION=0.28.0
RUN apk add --no-cache firefox libzip-dev; \
    docker-php-ext-install zip
RUN wget -q https://github.com/mozilla/geckodriver/releases/download/v$GECKODRIVER_VERSION/geckodriver-v$GECKODRIVER_VERSION-linux64.tar.gz; \
    tar -zxf geckodriver-v$GECKODRIVER_VERSION-linux64.tar.gz -C /usr/bin; \
    rm geckodriver-v$GECKODRIVER_VERSION-linux64.tar.gz

Build it with docker build . -t myproject Run it with docker run -it -v "$PWD":/srv/myproject -w /srv/myproject myproject bin/phpunit

GitHub Actions Integration

Panther works out of the box with GitHub Actions. Here is a minimal .github/workflows/panther.yml file to run Panther tests:

name: Run Panther tests

on: [ push, pull_request ]

jobs:
  tests:

    runs-on: ubuntu-latest

    steps:
      - uses: actions/checkout@v2

      - name: Install dependencies
        run: composer install -q --no-ansi --no-interaction --no-scripts --no-progress --prefer-dist

      - name: Run test suite
        run: bin/phpunit

Travis CI Integration

Panther will work out of the box with Travis CI if you add the Chrome addon. Here is a minimal .travis.yml file to run Panther tests:

language: php
addons:
  # If you don't use Chrome, or Firefox, remove the corresponding line
  chrome: stable
  firefox: latest

php:
  - 8.0

script:
  - bin/phpunit

Gitlab CI Integration

Here is a minimal .gitlab-ci.yml file to run Panther tests with Gitlab CI:

image: ubuntu

before_script:
  - apt-get update
  - apt-get install software-properties-common -y
  - ln -sf /usr/share/zoneinfo/Asia/Tokyo /etc/localtime
  - apt-get install curl wget php php-cli php7.4 php7.4-common php7.4-curl php7.4-intl php7.4-xml php7.4-opcache php7.4-mbstring php7.4-zip libfontconfig1 fontconfig libxrender-dev libfreetype6 libxrender1 zlib1g-dev xvfb chromium-chromedriver firefox-geckodriver -y -qq
  - export PANTHER_NO_SANDBOX=1
  - export PANTHER_WEB_SERVER_PORT=9080
  - php -r "copy('https://getcomposer.org/installer', 'composer-setup.php');"
  - php composer-setup.php --install-dir=/usr/local/bin --filename=composer
  - php -r "unlink('composer-setup.php');"
  - composer install

test:
  script:
    - bin/phpunit

AppVeyor Integration

Panther will work out of the box with AppVeyor as long as Google Chrome is installed. Here is a minimal appveyor.yml file to run Panther tests:

build: false
platform: x86
clone_folder: c:\projects\myproject

cache:
  - '%LOCALAPPDATA%\Composer\files'

install:
  - ps: Set-Service wuauserv -StartupType Manual
  - cinst -y php composer googlechrome chromedriver firfox selenium-gecko-driver
  - refreshenv
  - cd c:\tools\php80
  - copy php.ini-production php.ini /Y
  - echo date.timezone="UTC" >> php.ini
  - echo extension_dir=ext >> php.ini
  - echo extension=php_openssl.dll >> php.ini
  - echo extension=php_mbstring.dll >> php.ini
  - echo extension=php_curl.dll >> php.ini
  - echo memory_limit=3G >> php.ini
  - cd %APPVEYOR_BUILD_FOLDER%
  - composer install --no-interaction --no-progress

test_script:
  - cd %APPVEYOR_BUILD_FOLDER%
  - php bin\phpunit

Usage with Other Testing Tools

If you want to use Panther with other testing tools like LiipFunctionalTestBundle or if you just need to use a different base class, Panther has got you covered. It provides you with the Symfony\Component\Panther\PantherTestCaseTrait and you can use it to enhance your existing test-infrastructure with some Panther awesomeness:

<?php

namespace App\Tests\Controller;

use Liip\FunctionalTestBundle\Test\WebTestCase;
use Symfony\Component\Panther\PantherTestCaseTrait;

class DefaultControllerTest extends WebTestCase
{
    use PantherTestCaseTrait; // this is the magic. Panther is now available.

    public function testWithFixtures(): void
    {
        $this->loadFixtures([]); // load your fixtures
        $client = self::createPantherClient(); // create your panther client

        $client->request('GET', '/');
    }
}

Limitations

The following features are not currently supported:

• Crawling XML documents (only HTML is supported)
• Updating existing documents (browsers are mostly used to consume data, not to create webpages)
• Setting form values using the multidimensional PHP array syntax
• Methods returning an instance of \DOMElement (because this library uses WebDriverElement internally)
• Selecting invalid choices in select

Pull Requests are welcome to fill the remaining gaps!

Troubleshooting

Run with Bootstrap 5

If you are using Bootstrap 5, then you may have a problem with testing. Bootstrap 5 implements a scrolling effect, which tends to mislead Panther.

To fix this, we advise you to deactivate this effect by setting the Bootstrap 5 $enable-smooth-scroll variable to false in your style file.

$enable-smooth-scroll: false;

Save the Panthers

Many of the wild cat species are highly threatened. If you like this software, help save the (real) panthers by donating to the Panthera organization.

Credits

Created by Kévin Dunglas. Sponsored by Les-Tilleuls.coop.

Panther is built on top of PHP WebDriver and several other FOSS libraries. It has been inspired by Nightwatch.js, a WebDriver-based testing tool for JavaScript.