Opções CLI

Todas os detalhes das opções CLI de cada componente Grid.

Diferentes secções estão disponíveis para configurar uma Grid. Cada secção tem opções que podem ser configuradas através de opções CLI.

Pode ver abaixo um mapeamento entre o componente e a secção respectiva.

Note que esta documentação pode estar desactualizada se uma opção foi adicionada ou modificada, mas ainda não ter havido oportunidade de actualizar a documentação. Caso depare com esta situação, verifique a secção “ajuda de configuração” e esteja à vontade para nos enviar um pull request com alterações a esta página.

Secções

StandaloneHubNodeDistributorRouterSessionsSessionQueue
Distributor
Docker
Events
Logging
Network
Node
Router
Relay
Server
SessionQueue
Sessions

Distributor

OpçãoTipoValor/ExemploDescrição
--healthcheck-intervalint120Tempo em segundos em que se verifica o estado dos Nodes. Isto garante que o servidor consecontactar cada um dos Nodes com sucesso.
--distributorurihttp://localhost:5553Url do Distributor.
--distributor-hoststringlocalhostHost onde o Distributor está à escuta.
--distributor-implementationstringorg.openqa.selenium.grid.distributor.local.LocalDistributorNome completo da class para uma implementação não padrão do Distributor.
--distributor-portint5553Porta onde o Distributor está à escuta.
--reject-unsupported-capsbooleanfalsePermitir que o Distributor rejeite imediatamente um pedido de sessão se a Grid não suportar a capacidade pedida. Esta configuração é a ideal para Grid que não inicie Nodes a pedido.
--slot-matcherstringorg.openqa.selenium.grid.data.DefaultSlotMatcherNome completo da class para uma implementação não padrão do comparador de slots. Isto é usado para determinar se um Node pode suportar uma sessão em particular.
--slot-selectorstringorg.openqa.selenium.grid.distributor.selector.DefaultSlotSelectorNome completo da class para uma implementação não padrão do selector de slots. Isto é usado para selecionar um slot no Node caso tenha sido “matched”.

Docker

OpçãoTipoValor/ExemploDescrição
--docker-assets-pathstring/opt/selenium/assetsAbsolute path where assets will be stored
--docker-string[]selenium/standalone-firefox:latest '{"browserName": "firefox"}'Docker configs which map image name to stereotype capabilities (example `-D selenium/standalone-firefox:latest ‘{“browserName”: “firefox”}’)
--docker-devicesstring[]/dev/kvm:/dev/kvmExposes devices to a container. Each device mapping declaration must have at least the path of the device in both host and container separated by a colon like in this example: /device/path/in/host:/device/path/in/container
--docker-hoststringlocalhostHost name where the Docker daemon is running
--docker-portint2375Port where the Docker daemon is running
--docker-urlstringhttp://localhost:2375URL for connecting to the Docker daemon
--docker-video-imagestringselenium/video:latestDocker image to be used when video recording is enabled

Events

OpçãoTipoValor/ExemploDescrição
--bind-busbooleanfalseWhether the connection string should be bound or connected.
When true, the component will be bound to the Event Bus (as in the Event Bus will also be started by the component, typically by the Distributor and the Hub).
When false, the component will connect to the Event Bus.
--events-implementationstringorg.openqa.selenium.events.zeromq.ZeroMqEventBusFull class name of non-default event bus implementation
--publish-eventsstringtcp://*:4442Connection string for publishing events to the event bus
--subscribe-eventsstringtcp://*:4443Connection string for subscribing to events from the event bus

Logging

OpçãoTipoValor/ExemploDescrição
--http-logsbooleanfalseEnable http logging. Tracing should be enabled to log http logs.
--log-encodingstringUTF-8Log encoding
--logstringWindows path example :
'\path\to\file\gridlog.log'
or
'C:\path\path\to\file\gridlog.log'

Linux/Unix/MacOS path example :
'/path/to/file/gridlog.log'
File to write out logs. Ensure the file path is compatible with the operating system’s file path.
--log-levelstring“INFO”Log level. Default logging level is INFO. Log levels are described here https://docs.oracle.com/javase/7/docs/api/java/util/logging/Level.html
--plain-logsbooleantrueUse plain log lines
--structured-logsbooleanfalseUse structured logs
--tracingbooleantrueEnable trace collection
--log-timestamp-formatstringHH:mm:ss.SSSAllows the configure log timestamp format

Network

OpçãoTipoValor/ExemploDescrição
--relax-checksbooleanfalseRelax checks on origin header and content type of incoming requests, in contravention of strict W3C spec compliance.

Node

OpçãoTipoValor/ExemploDescrição
--detect-driversbooleantrueAutodetect which drivers are available on the current system, and add them to the Node.
--driver-configurationstring[]display-name="Firefox Nightly" max-sessions=2 webdriver-path="/usr/local/bin/geckodriver" stereotype="{\"browserName\": \"firefox\", \"browserVersion\": \"86\", \"moz:firefoxOptions\": {\"binary\":\"/Applications/Firefox Nightly.app/Contents/MacOS/firefox-bin\"}}"List of configured drivers a Node supports. It is recommended to provide this type of configuration through a toml config file to improve readability
--driver-factorystring[]org.openqa.selenium.example.LynxDriverFactory '{"browserName": "lynx"}'Mapping of fully qualified class name to a browser configuration that this matches against.
--driver-implementationstring[]"firefox"Drivers that should be checked. If specified, will skip autoconfiguration.
--node-implementationstring"org.openqa.selenium.grid.node.local.LocalNodeFactory"Full classname of non-default Node implementation. This is used to manage a session’s lifecycle.
--grid-urlstringhttps://grid.example.comPublic URL of the Grid as a whole (typically the address of the Hub or the Router)
--heartbeat-periodint60How often, in seconds, will the Node send heartbeat events to the Distributor to inform it that the Node is up.
--max-sessionsint8Maximum number of concurrent sessions. Default value is the number of available processors.
--override-max-sessionsbooleanfalseThe # of available processors is the recommended max sessions value (1 browser session per processor). Setting this flag to true allows the recommended max value to be overwritten. Session stability and reliability might suffer as the host could run out of resources.
--register-cycleint10How often, in seconds, the Node will try to register itself for the first time to the Distributor.
--register-periodint120How long, in seconds, will the Node try to register to the Distributor for the first time. After this period is completed, the Node will not attempt to register again.
--session-timeoutint300Let X be the session-timeout in seconds. The Node will automatically kill a session that has not had any activity in the last X seconds. This will release the slot for other tests.
--vnc-env-varstringSTART_XVFBEnvironment variable to check in order to determine if a vnc stream is available or not.
--no-vnc-portint7900If VNC is available, sets the port where the local noVNC stream can be obtained
--drain-after-session-countint1Drain and shutdown the Node after X sessions have been executed. Useful for environments like Kubernetes. A value higher than zero enables this feature.
--hubstringhttp://localhost:4444The address of the Hub in a Hub-and-Node configuration. Can be a hostname or IP address (hostname), in which case the Hub will be assumed to be http://hostname:4444, the --grid-url will be the same --publish-events will be tcp://hostname:4442 and --subscribe-events will be tcp://hostname:4443. If hostname contains a port number, that will be used for --grid-url but the URIs for the event bus will remain the same. Any of these default values may be overridden but setting the correct flags. If the hostname has a protocol (such as https) that will be used too.
--enable-cdpbooleantrueEnable CDP proxying in Grid. A Grid admin can disable CDP if the network doesnot allow websockets. True by default.
--enable-managed-downloadsbooleanfalseThis causes the Node to auto manage files downloaded for a given session on the Node.
--selenium-managerbooleanfalseWhen drivers are not available on the current system, use Selenium Manager. False by default.

Relay

OpçãoTipoValor/ExemploDescrição
--service-urlstringhttp://localhost:4723URL for connecting to the service that supports WebDriver commands like an Appium server or a cloud service.
--service-hoststringlocalhostHost name where the service that supports WebDriver commands is running
--service-portint4723Port where the service that supports WebDriver commands is running
--service-status-endpointstring/statusOptional, endpoint to query the WebDriver service status, an HTTP 200 response is expected
--service-configurationstring[]max-sessions=2 stereotype='{"browserName": "safari", "platformName": "iOS", "appium:platformVersion": "14.5"}}'Configuration for the service where calls will be relayed to. It is recommended to provide this type of configuration through a toml config file to improve readability.

Router

OpçãoTipoValor/ExemploDescrição
--passwordstringmyStrongPasswordPassword clients must use to connect to the server. Both this and the username need to be set in order to be used.
--usernamestringadminUser name clients must use to connect to the server. Both this and the password need to be set in order to be used.
--sub-pathstringmy_company/selenium_gridA sub-path that should be considered for all user facing routes on the Hub/Router/Standalone.

Server

OpçãoTipoValor/ExemploDescrição
--allow-corsbooleantrueWhether the Selenium server should allow web browser connections from any host
--hoststringlocalhostServer IP or hostname: usually determined automatically.
--bind-hostbooleantrueWhether the server should bind to the host address/name, or only use it to" report its reachable url. Helpful in complex network topologies where the server cannot report itself with the current IP/hostname but rather an external IP or hostname (e.g. inside a Docker container)
--https-certificatepath/path/to/cert.pemServer certificate for https. Get more detailed information by running “java -jar selenium-server.jar info security”
--https-private-keypath/path/to/key.pkcs8Private key for https. Get more detailed information by running “java -jar selenium-server.jar info security”
--max-threadsint24Maximum number of listener threads. Default value is: (available processors) * 3.
--portint4444Port to listen on. There is no default as this parameter is used by different components, for example, Router/Hub/Standalone will use 4444 and Node will use 5555.

SessionQueue

OpçãoTipoValor/ExemploDescrição
--sessionqueueurihttp://localhost:1237Address of the session queue server.
-sessionqueue-hoststringlocalhostHost on which the session queue server is listening.
--sessionqueue-portint1234Port on which the session queue server is listening.
--session-request-timeoutint300Timeout in seconds. A new incoming session request is added to the queue. Requests sitting in the queue for longer than the configured time will timeout.
--session-retry-intervalint5Retry interval in seconds. If all slots are busy, new session request will be retried after the given interval.

Sessions

OpçãoTipoValor/ExemploDescrição
--sessionsurihttp://localhost:1234Address of the session map server.
--sessions-hoststringlocalhostHost on which the session map server is listening.
--sessions-portint1234Port on which the session map server is listening.

Configuration examples

All the options mentioned above can be used when starting the Grid components. They are a good way of exploring the Grid options, and trying out values to find a suitable configuration.

We recommend the use of Toml files to configure a Grid. Configuration files improve readability, and you can also check them in source control.

When needed, you can combine a Toml file configuration with CLI arguments.

Command-line flags

To pass config options as command-line flags, identify the valid options for the component and follow the template below.

java -jar selenium-server-<version>.jar <component> --<option> value

Standalone, setting max sessions and main port

java -jar selenium-server-<version>.jar standalone --max-sessions 4 --port 4444

Hub, setting a new session request timeout, a main port, and disabling tracing

java -jar selenium-server-<version>.jar hub --session-request-timeout 500 --port 3333 --tracing false

Node, with 4 max sessions, with debug(fine) log, 7777 as port, and only with Firefox and Edge

java -jar selenium-server-<version>.jar node --max-sessions 4 --log-level "fine" --port 7777 --driver-implementation "firefox" --driver-implementation "edge"

Distributor, setting Session Map server url, Session Queue server url, and disabling bus

java -jar selenium-server-<version>.jar distributor --sessions http://localhost:5556 --sessionqueue http://localhost:5559 --bind-bus false

Setting custom capabilities for matching specific Nodes

Important: Custom capabilities need to be set in the configuration in all Nodes. They also need to be included always in every session request.

Start the Hub
java -jar selenium-server-<version>.jar hub
Start the Node A with custom cap set to true
java -jar selenium-server-<version>.jar node --detect-drivers false --driver-configuration display-name="Chrome (custom capability true)" max-sessions=1 stereotype='{"browserName":"chrome","gsg:customcap":true}' --port 6161
Start the Node B with custom cap set to false
java -jar selenium-server-<version>.jar node --detect-drivers false --driver-configuration display-name="Chrome (custom capability true)" max-sessions=1 stereotype='{"browserName":"chrome","gsg:customcap":false}' --port 6262
Matching Node A
ChromeOptions options = new ChromeOptions();
options.setCapability("gsg:customcap", true);
WebDriver driver = new RemoteWebDriver(new URL("http://localhost:4444"), options);
driver.get("https://selenium.dev");
driver.quit();

Set the custom capability to false in order to match the Node B.

Enabling Managed downloads by the Node

At times a test may need to access files that were downloaded by it on the Node. To retrieve such files, following can be done.

Start the Hub
java -jar selenium-server-<version>.jar hub
Start the Node with manage downloads enabled
java -jar selenium-server-<version>.jar node --enable-managed-downloads true
Set the capability at the test level

Tests that want to use this feature should set the capability "se:downloadsEnabled"to true

options.setCapability("se:downloadsEnabled", true);
How does this work
  • The Grid infrastructure will try to match a session request with "se:downloadsEnabled" against ONLY those nodes which were started with --enable-managed-downloads true
  • If a session is matched, then the Node automatically sets the required capabilities to let the browser know, as to where should a file be downloaded.
  • The Node now allows a user to:
    • List all the files that were downloaded for a specific session and
    • Retrieve a specific file from the list of files.
  • The directory into which files were downloaded for a specific session gets automatically cleaned up when the session ends (or) timesout due to inactivity.

Note: Currently this capability is ONLY supported on:

  • Edge
  • Firefox and
  • Chrome browser
Listing files that can be downloaded for current session:
  • The endpoint to GET from is /session/<sessionId>/se/files.
  • The session needs to be active in order for the command to work.
  • The raw response looks like below:
{
  "value": {
    "names": [
      "Red-blue-green-channel.jpg"
    ]
  }
}

In the response the list of file names appear under the key names.

Dowloading a file:
  • The endpoint to POST from is /session/<sessionId>/se/files with a payload of the form {"name": "fileNameGoesHere}
  • The session needs to be active in order for the command to work.
  • The raw response looks like below:
{
  "value": {
    "filename": "Red-blue-green-channel.jpg",
    "contents": "Base64EncodedStringContentsOfDownloadedFileAsZipGoesHere"
  }
}
  • The response blob contains two keys,
    • filename - The file name that was downloaded.
    • contents - Base64 encoded zipped contents of the file.
  • The file contents are Base64 encoded and they need to be unzipped.
List files that can be downloaded

The below mentioned curl example can be used to list all the files that were downloaded by the current session in the Node, and which can be retrieved locally.

curl -X GET "http://localhost:4444/session/90c0149a-2e75-424d-857a-e78734943d4c/se/files"

A sample response would look like below:

{
  "value": {
    "names": [
      "Red-blue-green-channel.jpg"
    ]
  }
}
Retrieve a downloaded file

Assuming the downloaded file is named Red-blue-green-channel.jpg, and using curl, the file could be downloaded with the following command:

curl -H "Accept: application/json" \
-H "Content-Type: application/json; charset=utf-8" \
-X POST -d '{"name":"Red-blue-green-channel.jpg"}' \
"http://localhost:4444/session/18033434-fa4f-4d11-a7df-9e6d75920e19/se/files"

A sample response would look like below:

{
  "value": {
    "filename": "Red-blue-green-channel.jpg",
    "contents": "UEsDBBQACAgIAJpagVYAAAAAAAAAAAAAAAAaAAAAUmVkLWJsAAAAAAAAAAAAUmVkLWJsdWUtZ3JlZW4tY2hhbm5lbC5qcGdQSwUGAAAAAAEAAQBIAAAAcNkAAAAA"
  }
}
Complete sample code in Java

Below is an example in Java that does the following:

  • Sets the capability to indicate that the test requires automatic managing of downloaded files.
  • Triggers a file download via a browser.
  • Lists the files that are available for retrieval from the remote node (These are essentially files that were downloaded in the current session)
  • Picks one file and downloads the file from the remote node to the local machine.
import com.google.common.collect.ImmutableMap;

import org.openqa.selenium.By;
import org.openqa.selenium.io.Zip;
import org.openqa.selenium.json.Json;
import org.openqa.selenium.remote.RemoteWebDriver;
import org.openqa.selenium.remote.http.HttpClient;
import org.openqa.selenium.remote.http.HttpRequest;
import org.openqa.selenium.remote.http.HttpResponse;

import java.io.File;
import java.net.URL;
import java.nio.file.Files;
import java.util.List;
import java.util.Map;
import java.util.Optional;
import java.util.concurrent.TimeUnit;

import static org.openqa.selenium.remote.http.Contents.asJson;
import static org.openqa.selenium.remote.http.Contents.string;
import static org.openqa.selenium.remote.http.HttpMethod.GET;
import static org.openqa.selenium.remote.http.HttpMethod.POST;

public class DownloadsSample {

  public static void main(String[] args) throws Exception {
    // Assuming the Grid is running locally.
    URL gridUrl = new URL("http://localhost:4444");
    ChromeOptions options = new ChromeOptions();
    options.setCapability("se:downloadsEnabled", true);
    RemoteWebDriver driver = new RemoteWebDriver(gridUrl, options);
    try {
      demoFileDownloads(driver, gridUrl);
    } finally {
      driver.quit();
    }
  }

	private static void demoFileDownloads(RemoteWebDriver driver, URL gridUrl) throws Exception {
		driver.get("https://www.selenium.dev/selenium/web/downloads/download.html");
		// Download the two available files on the page
		driver.findElement(By.id("file-1")).click();
		driver.findElement(By.id("file-2")).click();

		// The download happens in a remote Node, which makes it difficult to know when the file
		// has been completely downloaded. For demonstration purposes, this example uses a
		// 10-second sleep which should be enough time for a file to be downloaded.
		// We strongly recommend to avoid hardcoded sleeps, and ideally, to modify your
		// application under test, so it offers a way to know when the file has been completely
		// downloaded.
		TimeUnit.SECONDS.sleep(10);

		//This is the endpoint which will provide us with list of files to download and also to
		//let us download a specific file.
		String downloadsEndpoint = String.format("/session/%s/se/files", driver.getSessionId());

		String fileToDownload;

		try (HttpClient client = HttpClient.Factory.createDefault().createClient(gridUrl)) {
			// To list all files that are were downloaded on the remote node for the current session
			// we trigger GET request.
			HttpRequest request = new HttpRequest(GET, downloadsEndpoint);
			HttpResponse response = client.execute(request);
			Map<String, Object> jsonResponse = new Json().toType(string(response), Json.MAP_TYPE);
			@SuppressWarnings("unchecked")
			Map<String, Object> value = (Map<String, Object>) jsonResponse.get("value");
			@SuppressWarnings("unchecked")
			List<String> names = (List<String>) value.get("names");
			// Let's say there were "n" files downloaded for the current session, we would like
			// to retrieve ONLY the first file.
			fileToDownload = names.get(0);
		}

		// Now, let's download the file
		try (HttpClient client = HttpClient.Factory.createDefault().createClient(gridUrl)) {
			// To retrieve a specific file from one or more files that were downloaded by the current session
			// on a remote node, we use a POST request.
			HttpRequest request = new HttpRequest(POST, downloadsEndpoint);
			request.setContent(asJson(ImmutableMap.of("name", fileToDownload)));
			HttpResponse response = client.execute(request);
			Map<String, Object> jsonResponse = new Json().toType(string(response), Json.MAP_TYPE);
			@SuppressWarnings("unchecked")
			Map<String, Object> value = (Map<String, Object>) jsonResponse.get("value");
			// The returned map would contain 2 keys,
			// filename - This represents the name of the file (same as what was provided by the test)
			// contents - Base64 encoded String which contains the zipped file.
			String zippedContents = value.get("contents").toString();
			// The file contents would always be a zip file and has to be unzipped.
			File downloadDir = Zip.unzipToTempDir(zippedContents, "download", "");
			// Read the file contents
			File downloadedFile = Optional.ofNullable(downloadDir.listFiles()).orElse(new File[]{})[0];
			String fileContent = String.join("", Files.readAllLines(downloadedFile.toPath()));
			System.out.println("The file which was "
					+ "downloaded in the node is now available in the directory: "
					+ downloadDir.getAbsolutePath() + " and has the contents: " + fileContent);
		}
	}


}
Última modificação February 5, 2024: Fixing docs for --driver-configuration (333ff8ee4c9)