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Selenium Standalone Service

Handling the Selenium server is out of scope of the actual WebdriverIO project. This service helps you to run Selenium seamlessly when running tests with the WDIO testrunner. It uses the well known selenium-standalone NPM package that automatically sets up the standalone server and all required driver for you.

Note: If you use this service you don't need any other driver services (e.g. wdio-chromedriver-service) anymore. All local browser can be started using this service.

Installation​

Before starting make sure you have JDK installed.

The easiest way is to keep @wdio/selenium-standalone-service as a devDependency in your package.json.

{
"devDependencies": {
"@wdio/selenium-standalone-service": "^7.7.4"
}
}

You can simple do it by:

npm install @wdio/selenium-standalone-service --save-dev

Instructions on how to install WebdriverIO can be found here.

Configuration​

By default, ChromeDriver, geckodriver and some other browser drivers based on the OS are available when installed on the host system. In order to use the service you need to add selenium-standalone to your service array:

/**
* simplified mode (available since v6.11.0)
* set `true` to use the version provided by `selenium-standalone`, 'latest' by default
*/
exports.config
// ...
services: [
['selenium-standalone', { drivers: { firefox: '0.29.1', chrome: true, chromiumedge: 'latest' } }]
],
// ...
};

Control browser driver installation/running separately.

// wdio.conf.js
const drivers = {
chrome: { version: '91.0.4472.101' }, // https://chromedriver.chromium.org/
firefox: { version: '0.29.1' }, // https://github.com/mozilla/geckodriver/releases
chromiumedge: { version: '85.0.564.70' } // https://developer.microsoft.com/en-us/microsoft-edge/tools/webdriver/
}

exports.config
// ...
services: [
['selenium-standalone', {
logPath: 'logs',
installArgs: { drivers }, // drivers to install
args: { drivers } // drivers to use
}]
],
// ...
};

Custom Configurations​

By default the service starts on localhost:4444 and ensures that all capabilities are able to connect to it. If you prefer to run on a different port please specify port as an option in your capabilities, e.g.:

// wdio.conf.js
exports.config
// ...
services: [
['selenium-standalone', {
logPath: './temp',
args: {
version: "3.141.59",
seleniumArgs: ['-host', '127.0.0.1','-port', '5555']
},
}]
],
capabilities: [{
browserName: 'chrome',
port: 5555
}, {
browserName: 'firefox',
port: 5555
}, {
browserName: 'MicrosoftEdge',
port: 5555
}]
// ...
}

Options​

The following options can be added to the wdio.conf.js file.

logPath​

Path where all logs from the Selenium server should be stored.

Type: String

Default: {}

Example:

logPath : './',

args​

Map of arguments for the Selenium server, passed directly to Selenium.start(). Please note that latest drivers have to be installed, see installArgs.

Type: Object

Default: {}

Example:

args: {
version : "3.141.59",
drivers : {
chrome : {
version : "91.0.4472.101",
arch : process.arch
}
}
},

installArgs​

Map of arguments for the Selenium server, passed directly to Selenium.install().

By default, versions will be installed based on what is set in the selenium-standalone package. The defaults can be overridden by specifying the versions.

Type: Object

Default: {}

Example:

installArgs: {
version : "3.141.59",
baseURL : "https://github.com/SeleniumHQ/selenium/releases/download",
drivers : {
chrome : {
version : "91.0.4472.101",
arch : process.arch,
baseURL : "https://chromedriver.storage.googleapis.com"
}
}
},

skipSeleniumInstall​

Boolean for skipping selenium-standalone server install.

Type: Boolean

Default: false


For more information on WebdriverIO see the homepage.