Appium Espresso Driver

Appium's Espresso Driver is a test automation server for Android that uses Espresso as the underlying test technology. The Espresso Driver is a part of the Appium framework. The driver operates in scope of W3C WebDriver protocol with several custom extensions to cover operating-system specific scenarios.

The Espresso package consists of two main parts:

• The driver part (written in Node.js) ensures the communication between the Espresso server and Appium. Also includes several handlers that directly use ADB and/or other system tools without a need to talk to the server.
• The server part (written in Kotlin with some parts of Java), which is running on the device under test and transforms REST API calls into low-level Espresso commands.

Comparison with UiAutomator2

The key difference between UiAutomator2 Driver and Espresso Driver is that UiAutomator2 is a black-box testing framework, and Espresso is a "grey-box" testing framework. The Espresso Driver itself is black-box (no internals of the code are exposed to the tester), but the Espresso framework itself has access to the internals of Android applications. This distinction has a few notable benefits. It can find elements that aren't rendered on the screen, it can identify elements by the Android View Tag and it makes use of IdlingResource which blocks the framework from running commands until the UI thread is free. There is limited support to automate out of app areas using the mobile command uiautomator

Requirements

On top of standard Appium requirements Espresso driver also expects the following prerequisites:

• Windows, Linux and macOS are supported as hosts
• Android SDK Platform tools must be installed. Android Studio IDE also provides a convenient UI to install and manage the tools.
• ANDROID_HOME or ANDROID_SDK_ROOT environment variable must be set
• Java JDK must be installed and JAVA_HOME environment variable must be set. Android SDK below API 30 requires Java 8. Android SDK 30 and above requires Java 9 or newer.
• Emulator platform image must be installed if you plan to run your tests on it. Android Studio IDE also provides a convenient UI to install and manage emulators.
• Real Android devices must have USB debugging enabled and should be visible as online in adb devices -l output.
• The minimum version of Android API must be 5.0 (API level 21) (6.0 is recommended as version 5 has some known compatibility issues).
• Gradle must be installed in order to build Espresso server.
• Both the server package and the application under test must be signed with the same digital signature. Appium does sign them automatically upon session creation, so this could only be an issue if one wants to test an application, which is already installed on the device (using noReset=true capability).
• The package under test must not have mangled class names (e.g. Proguard must not be enabled for it)

Capabilities

General

Capability Name	Description
platformName	Could be set to android. Appium itself is not strict about this capability value if automationName is provided, so feel free to assign it to any supported platform name if this is needed, for example, to make Selenium Grid working.
appium:automationName	Must always be set to espresso. Values of automationName are compared case-insensitively.
appium:deviceName	The name of the device under test (actually, it is not used to select a device under test). Consider setting udid for real devices and avd for emulators instead
appium:platformVersion	The platform version of an emulator or a real device. This capability is used for device autodetection if udid is not provided
appium:udid	UDID of the device to be tested. Could ve retrieved from adb devices -l output. If unset then the driver will try to use the first connected device. Always set this capability if you run parallel tests.
appium:noReset	Prevents the device to be reset before the session startup if set to true. This means that the application under test is not going to be terminated neither its data cleaned. false by default
appium:fullReset	Being set to true always enforces the application under test to be fully uninstalled before starting a new session. false by default
appium:printPageSourceOnFindFailure	Enforces the server to dump the actual XML page source into the log if any error happens. false by default.

Driver/Server

Capability Name	Description
appium:systemPort	The number of the port the Espresso server is listening on. By default the first free port from 8300..8399 range is selected. It is recommended to set this value if you are running parallel tests on the same machine.
appium:skipServerInstallation	Skip the Espresso Server component installation on the device under test and all the related checks if set to true. This could help to speed up the session startup if you know for sure the correct server version is installed on the device. In case the server is not installed or an incorrect version of it is installed then you may get an unexpected error later. false by default
appium:espressoServerLaunchTimeout	The maximum number of milliseconds to wait util Espresso server is listening on the device. 45000 ms by default
appium:forceEspressoRebuild	Whether to always enforce Espresso server rebuild (true). By default Espresso caches the already built server apk and only rebuilds it when it is necessary, because rebuilding process needs extra time. false by default
appium:espressoBuildConfig	Either the full path to build config JSON on the server file system or the JSON content itself serialized to a string. This config allows to customize several important properties of Espresso server. Refer to Espresso Build Config for more information on how to properly construct such config.
appium:showGradleLog	Whether to include Gradle log to the regular server logs while building Espresso server. false by default.

App

Capability Name	Description
appium:app	Full path to the application to be tested (the app must be located on the same machine where the server is running). Both .apk and .apks application extensions are supported. Could also be an URL to a remote location. If neither of the app or appPackage capabilities are provided then the driver will fail to start a session. Also, if app capability is not provided it is expected that the app under test is already installed on the device under test and noReset is equal to true.
appium:appPackage	Application package identifier to be started. If not provided then Espresso will try to detect it automatically from the package provided by the app capability. Read How To Troubleshoot Activities Startup for more details
appium:appActivity	Main application activity identifier. If not provided then Espresso will try to detect it automatically from the package provided by the app capability. Read How To Troubleshoot Activities Startup for more details
appium:appWaitActivity	Identifier of the first activity that the application invokes. If not provided then equals to appium:appActivity. Read How To Troubleshoot Activities Startup for more details
appium:appWaitPackage	Identifier of the first package that is invoked first. If not provided then equals to appium:appPackage. Read How To Troubleshoot Activities Startup for more details
appium:appWaitDuration	Maximum amount of milliseconds to wait until the application under test is started (e. g. an activity returns the control to the caller). 20000 ms by default. Read How To Troubleshoot Activities Startup for more details
appium:intentOptions	The mapping of custom options for the intent that is going to be passed to the main app activity. Check Intent Options for more details.
appium:activityOptions	The mapping of custom options for the main app activity that is going to be started. Check Activity Options for more details.
appium:androidInstallTimeout	Maximum amount of milliseconds to wait until the application under test is installed. 90000 ms by default
appium:autoGrantPermissions	Whether to grant all the requested application permissions automatically when a test starts(true). false by default
appium:otherApps	Allows to set one or more comma-separated paths to Android packages that are going to be installed along with the main application under test. This might be useful if the tested app has dependencies
appium:uninstallOtherPackages	Allows to set one or more comma-separated package identifiers to be uninstalled from the device before a test starts
appium:allowTestPackages	If set to true then it would be possible to use packages built with the test flag for the automated testing (literally adds -t flag to the adb install command). false by default
appium:remoteAppsCacheLimit	Sets the maximum amount of application packages to be cached on the device under test. This is needed for devices that don't support streamed installs (Android 7 and below), because ADB must push app packages to the device first in order to install them, which takes some time. Setting this capability to zero disables apps caching. 10 by default.
appium:enforceAppInstall	If set to true then the application under test is always reinstalled even if a newer version of it already exists on the device under test. false by default

App Localization

Capability Name	Description
appium:localeScript	Canonical name of the locale to be set for the app under test, for example zh-Hans-CN. See https://developer.android.com/reference/java/util/Locale.html for more details.
appium:language	Name of the language to extract application strings for. Strings are extracted for the current system language by default. Also sets the language for the app under test. See https://developer.android.com/reference/java/util/Locale.html for more details. Example: en, ja
appium:locale	Sets the locale for the app under test. See https://developer.android.com/reference/java/util/Locale.html for more details. Example: EN, JA
appium:appLocale	Sets the locale for the app under test. The main difference between this option and the above ones is that this option only changes the locale for the application under test and does not affect other parts of the system. Also, it only uses public APIs for its purpose. See https://github.com/libyal/libfwnt/wiki/Language-Code-identifiers to get the list of available language abbreviations. Example: {"language": "zh", "country": "CN", "variant": "Hans"}

ADB

Capability Name	Description
appium:adbPort	Number of the port where ADB is running. 5037 by default
appium:remoteAdbHost	Address of the host where ADB is running (the value of -H ADB command line option). Unset by default
appium:adbExecTimeout	Maximum number of milliseconds to wait until single ADB command is executed. 20000 ms by default
appium:clearDeviceLogsOnStart	If set to true then Espresso deletes all the existing logs in the device buffer before starting a new test
appium:buildToolsVersion	The version of Android build tools to use. By default Espresso driver uses the most recent version of build tools installed on the machine, but sometimes it might be necessary to give it a hint (let say if there is a known bug in the most recent tools version). Example: 28.0.3
appium:skipLogcatCapture	Being set to true disables automatic logcat output collection during the test run. false by default
appium:suppressKillServer	Being set to true prevents the driver from ever killing the ADB server explicitly. Could be useful if ADB is connected wirelessly. false by default
appium:ignoreHiddenApiPolicyError	Being set to true ignores a failure while changing hidden API access policies. Could be useful on some devices, where access to these policies has been locked by its vendor. false by default.
appium:mockLocationApp	If set to true then location mocking app gets assigned to Appium Settings (the default behavior), so Appium could mock GPS location. The false value prevents that from happening.
appium:logcatFormat	The log print format, where format is one of: brief process tag thread raw time threadtime long. threadtime is the default value.
appium:logcatFilterSpecs	Series of tag[:priority] where tag is a log component tag (or * for all) and priority is: V Verbose, D Debug, I Info, W Warn, E Error, F Fatal, S Silent (supress all output). '' means ':d' and tag by itself means tag:v. If not specified on the commandline, filterspec is set from ANDROID_LOG_TAGS. If no filterspec is found, filter defaults to '*:I'.
appium:allowDelayAdb	Being set to false prevents emulator to use -delay-adb feature to detect its startup. See appium/appium#14773 for more details.

Emulator (Android Virtual Device)

Capability Name	Description
appium:avd	The name of Android emulator to run the test on. The names of currently installed emulators could be listed using avdmanager list avd command. If the emulator with the given name is not running then it is going to be started before a test
appium:avdLaunchTimeout	Maximum number of milliseconds to wait until Android Emulator is started. 60000 ms by default
appium:avdReadyTimeout	Maximum number of milliseconds to wait until Android Emulator is fully booted and is ready for usage. 60000 ms by default
appium:avdArgs	Either a string or an array of emulator command line arguments.
appium:avdEnv	Mapping of emulator environment variables.
appium:networkSpeed	Sets the desired network speed limit for the emulator. It is only applied if the emulator is not running before the test starts. See emulator command line arguments description for more details.
appium:gpsEnabled	Sets whether to enable (true) or disable (false) GPS service in the Emulator. Unset by default, which means to not change the current value
appium:isHeadless	If set to true then emulator starts in headless mode (e.g. no UI is shown). It is only applied if the emulator is not running before the test starts. false by default.

App Signing

Capability Name	Description
appium:useKeystore	Whether to use a custom keystore to sign the app under test. false by default, which means apps are always signed with the default Appium debug certificate (unless canceled by noSign capability). This capability is used in combination with keystorePath, keystorePassword, keyAlias and keyPassword capabilities.
appium:keystorePath	The full path to the keystore file on the server filesystem. This capability is used in combination with useKeystore, keystorePath, keystorePassword, keyAlias and keyPassword capabilities. Unset by default
appium:keystorePassword	The password to the keystore file provided in keystorePath capability. This capability is used in combination with useKeystore, keystorePath, keystorePassword, keyAlias and keyPassword capabilities. Unset by default
appium:keyAlias	The alias of the key in the keystore file provided in keystorePath capability. This capability is used in combination with useKeystore, keystorePath, keystorePassword, keyAlias and keyPassword capabilities. Unset by default
appium:keyPassword	The password of the key in the keystore file provided in keystorePath capability. This capability is used in combination with useKeystore, keystorePath, keystorePassword, keyAlias and keyPassword capabilities. Unset by default
appium:noSign	Set it to true in order to skip application signing. By default all apps are always signed with the default Appium debug signature. This capability cancels all the signing checks and makes the driver to use the application package as is. This capability does not affect .apks packages as these are expected to be already signed. Make sure that the server package is signed with the same signature as the application under test before disabling this capability.

Device Locking

Capability Name	Description
appium:skipUnlock	Whether to skip the check for lock screen presence (true). By default Espresso driver tries to detect if the device's screen is locked before starting the test and to unlock that (which sometimes might be unstable). Note, that this operation takes some time, so it is highly recommended to set this capability to false and disable screen locking on devices under test.
appium:unlockType	Set one of the possible types of Android lock screens to unlock. Read the Unlock tutorial for more details.
appium:unlockKey	Allows to set an unlock key. Read the Unlock tutorial for more details.
appium:unlockSuccessTimeout	Maximum number of milliseconds to wait until the device is unlocked. 2000 ms by default

Web Context

Capability Name	Description
appium:autoWebview	If set to true then Espresso driver will try to switch to the first available web view after the session is started. false by default.
appium:webviewDevtoolsPort	The local port number to use for devtools communication. By default the first free port from 10900..11000 range is selected. Consider setting the custom value if you are running parallel tests.
appium:ensureWebviewsHavePages	Whether to skip web views that have no pages from being shown in getContexts output. The driver uses devtools connection to retrieve the information about existing pages. true by default.
appium:enableWebviewDetailsCollection	Whether to retrieve extended web views information using devtools protocol. Enabling this capability helps to detect the necessary chromedriver version more precisely. false by default.
appium:chromedriverPort	The port number to use for Chromedriver communication. Any free port number is selected by default if unset.
appium:chromedriverPorts	Array of possible port numbers to assign for Chromedriver communication. If none of the port in this array is free then an error is thrown.
appium:chromedriverArgs	Array of chromedriver command line arguments. Note, that not all command line arguments that are available for the desktop browser are also available for the mobile one.
appium:chromedriverExecutable	Full path to the chromedriver executable on the server file system.
appium:chromedriverExecutableDir	Full path to the folder where chromedriver executables are located. This folder is used then to store the downloaded chromedriver executables if automatic download is enabled. Read Automatic Chromedriver Discovery article for more details.
appium:chromedriverChromeMappingFile	Full path to the chromedrivers mapping file. This file is used to statically map webview/browser versions to the chromedriver versions that are capable of automating them. Read Automatic Chromedriver Discovery article for more details.
appium:chromedriverUseSystemExecutable	Set it to true in order to enforce the usage of chromedriver, which gets downloaded by Appium automatically upon installation. This driver might not be compatible with the destination browser or a web view. false by default.
appium:chromedriverDisableBuildCheck	Being set to true disables the compatibility validation between the current chromedriver and the destination browser/web view. Use it with care.
appium:autoWebviewTimeout	Set the maximum number of milliseconds to wait until a web view is available if autoWebview capability is set to true. 2000 ms by default
appium:recreateChromeDriverSessions	If this capability is set to true then chromedriver session is always going to be killed and then recreated instead of just suspending it on context switching. false by default
appium:nativeWebScreenshot	Whether to use screenshoting endpoint provided by Espresso framework (true) rather than the one provided by chromedriver (false, the default value). Use it when you experience issues with the latter.
appium:extractChromeAndroidPackageFromContextName	If set to true, tell chromedriver to attach to the android package we have associated with the context name, rather than the package of the application under test. false by default.
appium:showChromedriverLog	If set to true then all the output from chromedriver binary will be forwarded to the Appium server log. false by default.
pageLoadStrategy	One of the available page load strategies. See https://www.w3.org/TR/webdriver/#capabilities
appium:chromeOptions	A mapping, that allows to customize chromedriver options. See https://chromedriver.chromium.org/capabilities for the list of available entries.

Other

Capability Name	Description
appium:disableSuppressAccessibilityService	Being set to true tells the instrumentation process to not suppress accessibility services during the automated test. This might be useful if your automated test needs these services. false by default

Espresso Build Config

Espresso server is in tight connection with the application under test. That is why it is important that the server uses the same versions of common dependencies and there are no conflicts. Espresso driver allows to configure several build options via espressoBuildConfig capability. The configuration JSON supports the following entries:

toolsVersions

This entry allows to explicitly set the versions of different server components. The following map entries are supported:

Name	Description	Example
gradle	The Gradle version to use for Espresso server building.	'6.3'
androidGradlePlugin	The Gradle plugin version to use for Espresso server building. By default the version from the build.gradle.kts is used	'4.1.1'
compileSdk	Android SDK version to compile the server for. By default the version from the app build.gradle.kts is used	28
buildTools	Target Android build tools version to compile the server with. By default the version from the app build.gradle.kts is used	'28.0.3'
minSdk	Minimum Android SDK version to compile the server for. By default the version from the app build.gradle.kts is used	18
targetSdk	Target Android SDK version to compile the server for. By default the version from the app build.gradle.kts is used	28
kotlin	Kotlin version to compile the server for. By default the version from the build.gradle.kts is used	'1.3.72'

additionalAppDependencies

The value of this entry must be a non empty array of dependent module names with their versions. The scripts adds all these items as implementation lines of dependencies category in the app build.gradle.kts script. Example: ["xerces.xercesImpl:2.8.0", "xerces.xmlParserAPIs:2.6.2"]

additionalAndroidTestDependencies

The value of this entry must be a non empty array of dependent module names with their versions. The scripts adds all these items as androidTestImplementation lines of dependencies category in the app build.gradle.kts script. Example: ["xerces.xercesImpl:2.8.0", "xerces.xmlParserAPIs:2.6.2"]

Full JSON Example

{
  "toolsVersions": {
    "androidGradlePlugin": "4.0.0"
  },
  "additionalAndroidTestDependencies": ["xerces.xercesImpl:2.8.0", "xerces.xmlParserAPIs:2.6.2"]
}

Intent Options

By default Espresso creates the following intent to start the app activity:

{
  "action": "ACTION_MAIN",
  "flags": "ACTIVITY_NEW_TASK",
  "className": "<fullyQualifiedAppActivity>"
}

Although, it is possible to fully customize these options by providing the intentOptions capability. Read Intent documentation for more details on this topic. The value of this capability is expected to be a map with the following entries:

Name	Type	Description	Example
action	string	An action name. Application-specific actions should be prefixed with the vendor's package name.	ACTION_MAIN
data	string	Intent data URI	content://contacts/people/1
type	string	Intent MIME type	image/png
categories	string	One or more comma-separated Intent categories	android.intent.category.APP_CONTACTS
component	string	Component name with package name prefix to create an explicit intent	com.example.app/.ExampleActivity
intFlags	string	Single string value, which represents intent flags set encoded into an integer. Could also be provided in hexadecimal format. Check setFlags method documentation for more details.	0x0F
flags	Comma-separated string of intent flag names	'FLAG_GRANT_READ_URI_PERMISSION, ACTIVITY_CLEAR_TASK' (the 'FLAG_' prefix could be omitted)
className	The name of a class inside of the application package that will be used as the component for this Intent	com.example.app.MainActivity
e or es	Map<string, string>	Intent string parameters	{'foo': 'bar'}
esn	Array<string>	Intent null parameters	['foo', 'bar']
ez	Map<string, boolean>	Intent boolean parameters	{'foo': true, 'bar': false}
ei	Map<string, int>	Intent integer parameters	{'foo': 1, 'bar': 2}
el	Map<string, long>	Intent long integer parameters	{'foo': 1L, 'bar': 2L}
ef	Map<string, float>	Intent float parameters	{'foo': 1.ff, 'bar': 2.2f}
eu	Map<string, string>	Intent URI-data parameters	{'foo': 'content://contacts/people/1'}
ecn	Map<string, string>	Intent component name parameters	{'foo': 'com.example.app/.ExampleActivity'}
eia	Map<string, string>	Intent integer array parameters	{'foo': '1,2,3,4'}
ela	Map<string, string>	Intent long array parameters	{'foo': '1L,2L,3L,4L'}
efa	Map<string, string>	Intent float array parameters	{'foo': '1.1,2.2,3.2,4.4'}

Activity Options

Espresso driver allows to customize several activity startup options using activityOptions capability. The capability value is expected to be a map with the following entries:

Name	Type	Description	Example
launchDisplayId	string or int	Display id which you want to assign to launch the main app activity on. This might be useful if the device under test supports multiple displays	1

Element Attributes

Espresso driver supports the following element attributes:

Name	Description	Example
checkable	Whether the element is checkable or not	'true'
checked	Whether the element is checked. Always false if the element is not checkable	'false'
class	The full name of the element's class. Could be null for some elements	'android.view.View'
clickable	Whether the element could be clicked	'false'
content-desc	The content-description attribute of the accessible element	'foo'
enabled	Whether the element could be clicked	'true'
focusable	Whether the element could be focused	'true'
focused	Whether the element could is focused. Always false if the element is not focusable	'false'
long-clickable	Whether the element accepts long clicks	'false'
package	Identifier of the package the element belongs to	'com.mycompany'
password	Whether the element is a password input field	'true'
resource-id	Element's resource identifier. Could be null	'com.mycompany:id/resId'
scrollable	Whether the element is scrollable	'true'
selected	Whether the element is selected	'false'
text	The element's text. It never equals to null	'my text'
hint	The element's hint. Could be null	'my hint text'
bounds	The element's visible frame ([left, top][right, bottom])	[0,0][100,100]
no-multiline-buttons	Whether the element's view hierarchy does not contain multiline buttons	'true'
no-overlaps	Whether element's descendant objects assignable to TextView or ImageView do not overlap each other	'true'
no-ellipsized-text	Whether the element's view hierarchy does not contain ellipsized or cut off text views	'false'
visible	Whether the element is visible to the user	'true'
view-tag	The tag value assigned to the element. Could be null	'my tag'

Element Location

Espresso driver supports the following location strategies:

Name	Description	Example
id	This strategy is mapped to the native Espresso withId matcher (exact match of element's resource id). Package identifier prefix is added automatically if unset and is equal to the identifier of the current application under test.	'com.mycompany:id/resourceId'
accessibility id	This strategy is mapped to the native Espresso withContentDescription matcher (exact match of element's content description).	'my description'
class name	This strategy is mapped to the native Espresso withClassName matcher (exact match of element's class name).	'android.view.View'
text	This strategy is mapped to the native Espresso withText matcher (exact match of element's text).	'my text'
-android viewtag or tag name	This strategy is mapped to the native Espresso withTagValue matcher (exact match of element's tag value).	'my tag'
-android datamatcher	This strategy allows to create Espresso data interaction selectors which can quickly and reliably scroll to the necessary elements. Read Espresso DataMatcher Selector to know more on how to construct these locators. Also check the Unlocking New Testing Capabilities with Espresso Driver by Daniel Graham presentation video from Appium Conf 2019.	{"name": "hasEntry", "args": ["title", "WebView3"]}
-android viewmatcher	This strategy allows to construct Espresso view matcher based on the given JSON representation of it. The representation is expected to contain the following fields: name: the mandatory matcher function name; args: optional matcher function arguments, each argument could also be a function; class: the full qualified class name of the corresponding matcher.	{"name": "withText", "args": [{"name": "containsString", "args": "getExternalStoragePublicDirectory", "class": "org.hamcrest.Matchers"}], "class": "androidx.test.espresso.matcher.ViewMatchers"}
xpath	For elements lookup Xpath strategy the driver uses the same XML tree that is generated by page source API. Only Xpath 1.0 is supported.	By.xpath("//android.view.View[@text=\"Regular\" and @checkable=\"true\"]")

Platform-Specific Extensions

Beside of standard W3C APIs the driver provides the following custom command extensions to execute platform specific scenarios:

mobile: shell

Executes the given shell command on the device under test via ADB connection. This extension exposes a potential security risk and thus is only enabled when explicitly activated by the adb_shell server command line feature specifier

Arguments

Name	Type	Required	Description	Example
command	string	yes	Shell command name to execute, for example echo or rm	echo
args	Array<string>	no	Array of command arguments	['-f', '/sdcard/myfile.txt']
timeout	number	no	Command timeout in milliseconds. If the command blocks for longer than this timeout then an exception is going to be thrown. The default timeout is 20000 ms	100000
includeStderr	boolean	no	Whether to include stderr stream into the returned result. false by default	true

Returns

Depending on the includeStderr value this API could either return a string, which is equal to the stdout stream content of the given command or a dictionary whose elements are stdout and stderr and values are contents of the corresponding outgoing streams. If the command exits with a non-zero return code then an exception is going to be thrown. The exception message will be equal to the command stderr.

mobile: execEmuConsoleCommand

Executes a command through emulator telnet console interface and returns its output. The emulator_console server feature must be enabled in order to use this method.

Arguments

Name	Type	Required	Description	Example
command	string	yes	The actual command to execute. See Android Emulator Console Guide for more details on available commands	help-verbose
execTimeout	number	no	Timeout used to wait for a server reply to the given command in milliseconds. 60000 ms by default	100000
connTimeout	boolean	no	Console connection timeout in milliseconds. 5000 ms by default	10000
initTimeout	boolean	no	Telnet console initialization timeout in milliseconds (the time between the connection happens and the command prompt). 5000 ms by default	10000

Returns

The actual command output. An error is thrown if command execution fails.

mobile: performEditorAction

Performs IME action on the focused edit element. Read How To Emulate IME Actions Generation for more details.

mobile: changePermissions

Changes package permissions in runtime.

Arguments

Name	Type	Required	Description	Example
permissions	string or Array<string>	yes	The full name of the permission to be changed or a list of permissions. Mandatory argument.	['android.permission.ACCESS_FINE_LOCATION', 'android.permission.BROADCAST_SMS']
appPackage	string	no	The application package to set change permissions on. Defaults to the package name under test	com.mycompany.myapp
action	string	no	Either grant (the default action) or revoke	grant

mobile: getPermissions

Gets runtime permissions list for the given application package.

Arguments

Name	Type	Required	Description	Example
type	string	no	One of possible permission types to get. Can be one of: denied, granted or requested (the default value).	granted
appPackage	string	no	The application package to get permissions from. Defaults to the package name under test	com.mycompany.myapp

Returns

Array of strings, where each string is a permission name. the array could be empty.

mobile: startScreenStreaming

Starts device screen broadcast by creating MJPEG server. Multiple calls to this method have no effect unless the previous streaming session is stopped. This method only works if the adb_screen_streaming feature is enabled on the server side. It is also required that GStreamer with gst-plugins-base, gst-plugins-good and gst-plugins-bad packages is installed and available in PATH on the server machine.

Arguments

Name	Type	Required	Description	Example
width	number	no	The scaled width of the device's screen. If unset then the script will assign it to the actual screen width measured in pixels.	768
height	number	no	The scaled height of the device's screen. If unset then the script will assign it to the actual screen height measured in pixels.	1024
bitRate	number	no	The video bit rate for the video, in bits per second. The default value is 4000000 (4 Mb/s). You can increase the bit rate to improve video quality, but doing so results in larger movie files.	1024000
host	string	no	The IP address/host name to start the MJPEG server on. You can set it to 0.0.0.0 to trigger the broadcast on all available network interfaces. 127.0.0.1 by default	0.0.0.0
pathname	string	no	The HTTP request path the MJPEG server should be available on. If unset then any pathname on the given host/port combination will work. Note that the value should always start with a single slash: /	/myserver
tcpPort	number	no	The port number to start the internal TCP MJPEG broadcast on. This type of broadcast always starts on the loopback interface (127.0.0.1). 8094 by default	5024
port	number	no	The port number to start the MJPEG server on. 8093 by default	5023
quality	number	no	The quality value for the streamed JPEG images. This number should be in range [1, 100], where 100 is the best quality. 70 by default	80
considerRotation	boolean	no	If set to true then GStreamer pipeline will increase the dimensions of the resulting images to properly fit images in both landscape and portrait orientations. Set it to true if the device rotation is not going to be the same during the broadcasting session. false by default	false
logPipelineDetails	boolean	no	Whether to log GStreamer pipeline events into the standard log output. Might be useful for debugging purposes. false by default	true

mobile: stopScreenStreaming

Stop the previously started screen streaming. If no screen streaming server has been started then nothing is done.

mobile: deviceInfo

Retrieves the information about the device under test, like the device model, serial number, network connectivity info, etc.

Returns

The extension returns a dictionary whose entries are the device properties. Check https://github.com/appium/appium-espresso-driver/blob/master/espresso-server/app/src/androidTest/java/io/appium/espressoserver/lib/handlers/GetDeviceInfo.kt to get the full list of returned keys and their corresponding values.

mobile: swipe

Perform swipe action. Invokes Espresso swipe action under the hood.

Arguments

Name	Type	Required	Description	Example
element	string	yes	The UDID of the element to perform the swipe on.	123456-7890-3453-24234243
direction	string	no	Swipe direction. Either this argument or swiper must be provided, but not both. The following values are supported: up, down, left, right	down
swiper	string	no	Swipe speed. Either this argument or direction must be provided, but not both. Either FAST (Swipes quickly between the co-ordinates) or SLOW (Swipes deliberately slowly between the co-ordinates, to aid in visual debugging)	SLOW
startCoordinates	string	no	The starting coordinates for the action. The following values are supported: TOP_LEFT, TOP_CENTER, TOP_RIGHT, CENTER_LEFT, CENTER, CENTER_RIGHT, BOTTOM_LEFT, BOTTOM_CENTER (the default value), BOTTOM_RIGHT, VISIBLE_CENTER	CENTER_LEFT
endCoordinates	string	no	The ending coordinates for the action. The following values are supported: TOP_LEFT, TOP_CENTER (the default value), TOP_RIGHT, CENTER_LEFT, CENTER, CENTER_RIGHT, BOTTOM_LEFT, BOTTOM_CENTER, BOTTOM_RIGHT, VISIBLE_CENTER	TOP_LEFT
precisionDescriber	string	no	Defines the actual swipe precision. The following values are supported: PINPOINT (1px), FINGER (average width of the index finger is 16 – 20 mm), THUMB (average width of an adult thumb is 25 mm or 1 inch, the default value)	FINGER

mobile: isToastVisible

Checks whether a toast notification with the given text is currently visible.

Arguments

Name	Type	Required	Description	Example
text	string	yes	The actual toast test or a part of it	'toast text'
isRegexp	boolean	no	Whether the text value should be parsed as a regular expression (true) or as a raw text (false, the default value)	false

Returns

Either true or false

mobile: openDrawer

Opens the DrawerLayout drawer with the gravity. This method blocks until the drawer is fully open. No operation if the drawer is already open.

Arguments

Name	Type	Required	Description	Example
element	string	yes	UDID of the element to perform the action on.	123456-7890-3453-24234243
gravity	int	no	See GravityCompat and Gravity classes documentation	0x00800000 <bitwise_or> 0x00000003

mobile: closeDrawer

Closes the DrawerLayout drawer with the gravity. This method blocks until the drawer is fully closed. No operation if the drawer is already closed.

Arguments

Name	Type	Required	Description	Example
element	string	yes	UDID of the element to perform the action on.	123456-7890-3453-24234243
gravity	int	no	See GravityCompat and Gravity classes documentation	0x00800000 <bitwise_or> 0x00000005

mobile: scrollToPage

Perform scrolling to the given page. Invokes one of the ViewPagerActions under the hood. Which action is invoked depends on the given arguments.

Arguments

Name	Type	Required	Description	Example
element	string	yes	UDID of the element to perform the action on.	123456-7890-3453-24234243
scrollTo	string	no if scrollToPage is provided	Shifts ViewPager to the given page. Supported values are: first, last, left, right	last
scrollToPage	int	no if scrollTo is provided	Moves ViewPager to a specific page number (numbering starts from zero).	1
smoothScroll	boolean	no	Whether to perform smooth (but slower) scrolling (true). The default value is false	true

mobile: navigateTo

Invokes navigateTo action under the hood.

Arguments

Name	Type	Required	Description	Example
element	string	yes	UDID of the element to perform the action on. View constraints: View must be a child of a DrawerLayout; View must be of type NavigationView; View must be visible on screen; View must be displayed on screen	123456-7890-3453-24234243
menuItemId	int	yes	The resource id of the destination menu item	123

mobile: clickAction

Perform general click action.

Arguments

Name	Type	Required	Description	Example
element	string	yes	The UDID of the element to perform the click on.	123456-7890-3453-24234243
tapper	string	no	Tapper type. Supported types are: SINGLE (the default value), LONG, DOUBLE	LONG
coordinatesProvider	string	no	The coordinates for the action. The following values are supported: TOP_LEFT, TOP_CENTER, TOP_RIGHT, CENTER_LEFT, CENTER, CENTER_RIGHT, BOTTOM_LEFT, BOTTOM_CENTER, BOTTOM_RIGHT, VISIBLE_CENTER (the default value)	CENTER_LEFT
precisionDescriber	string	no	Defines the actual click precision. The following values are supported: PINPOINT (1px), FINGER (average width of the index finger is 16 – 20 mm, the default value), THUMB (average width of an adult thumb is 25 mm or 1 inch)	PINPOINT
inputDevice	int	no	Input device identifier, 0 by default	1
buttonState	int	no	Button state id, 0 by default	1

mobile: getContexts

Retrieves a webviews mapping based on CDP endpoints

Returns

The following json demonstrates the example of WebviewsMapping object. Note that description in page can be an empty string most likely when it comes to Mobile Chrome)

 {
   "proc": "@webview_devtools_remote_22138",
   "webview": "WEBVIEW_22138",
   "info": {
     "Android-Package": "io.appium.settings",
     "Browser": "Chrome/74.0.3729.185",
     "Protocol-Version": "1.3",
     "User-Agent": "Mozilla/5.0 (Linux; Android 10; Android SDK built for x86 Build/QSR1.190920.001; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/74.0.3729.185 Mobile Safari/537.36",
     "V8-Version": "7.4.288.28",
     "WebKit-Version": "537.36 (@22955682f94ce09336197bfb8dffea991fa32f0d)",
     "webSocketDebuggerUrl": "ws://127.0.0.1:10900/devtools/browser"
   },
   "pages": [
     {
       "description": "{\"attached\":true,\"empty\":false,\"height\":1458,\"screenX\":0,\"screenY\":336,\"visible\":true,\"width\":1080}",
       "devtoolsFrontendUrl": "http://chrome-devtools-frontend.appspot.com/serve_rev/@22955682f94ce09336197bfb8dffea991fa32f0d/inspector.html?ws=127.0.0.1:10900/devtools/page/27325CC50B600D31B233F45E09487B1F",
       "id": "27325CC50B600D31B233F45E09487B1F",
       "title": "Releases · appium/appium · GitHub",
       "type": "page",
       "url": "https://github.com/appium/appium/releases",
       "webSocketDebuggerUrl": "ws://127.0.0.1:10900/devtools/page/27325CC50B600D31B233F45E09487B1F"
     }
   ],
   "webviewName": "WEBVIEW_com.io.appium.setting"
 }

mobile: getNotifications

Retrieves Android notifications via Appium Settings helper. Appium Settings app itself must be manually granted to access notifications under device Settings in order to make this feature working. Appium Settings helper keeps all the active notifications plus notifications that appeared while it was running in the internal buffer, but no more than 100 items altogether. Newly appeared notifications are always added to the head of the notifications array. The isRemoved flag is set to true for notifications that have been removed. See https://developer.android.com/reference/android/service/notification/StatusBarNotification and https://developer.android.com/reference/android/app/Notification.html for more information on available notification properties and their values.

Returns

The example output is:

{
   "statusBarNotifications":[
     {
       "isGroup":false,
       "packageName":"io.appium.settings",
       "isClearable":false,
       "isOngoing":true,
       "id":1,
       "tag":null,
       "notification":{
         "title":null,
         "bigTitle":"Appium Settings",
         "text":null,
         "bigText":"Keep this service running, so Appium for Android can properly interact with several system APIs",
         "tickerText":null,
         "subText":null,
         "infoText":null,
         "template":"android.app.Notification$BigTextStyle"
       },
       "userHandle":0,
       "groupKey":"0|io.appium.settings|1|null|10133",
       "overrideGroupKey":null,
       "postTime":1576853518850,
       "key":"0|io.appium.settings|1|null|10133",
       "isRemoved":false
     }
   ]
}

mobile: listSms

Retrieves the list of the most recent SMS properties list via Appium Settings helper. Messages are sorted by date in descending order.

Arguments

Name	Type	Required	Description	Example
max	number	no	The maximum count of recent messages to retrieve. 100 by default	10

Returns

The example output is:

 {
   "items":[
     {
       "id":"2",
       "address":"+123456789",
       "person":null,
       "date":"1581936422203",
       "read":"0",
       "status":"-1",
       "type":"1",
       "subject":null,
       "body":"\"text message2\"",
       "serviceCenter":null
     },
     {
       "id":"1",
       "address":"+123456789",
       "person":null,
       "date":"1581936382740",
       "read":"0",
       "status":"-1",
       "type":"1",
       "subject":null,
       "body":"\"text message\"",
       "serviceCenter":null
     }
   ],
   "total":2
 }

mobile: sensorSet

Emulate sensors values on the connected emulator.

Arguments

Name	Type	Required	Description	Example
sensorType	string	yes	Supported sensor types are: acceleration, light, proximity, temperature, pressure and humidity	light
value	string	yes	value to set to the sensor	50

mobile: deleteFile

Deletes a file on the remote device.

Arguments

Name	Type	Required	Description	Example
remotePath	string	yes	The full path to the remote file or a file inside an application bundle	/sdcard/myfile.txt or @my.app.id/path/in/bundle

mobile: startService

Starts the given service intent.

Arguments

Name	Type	Required	Description	Example
intent	string	yes	The name of the service intent to start. Only services in the app's under test scope could be started.	com.some.package.name/.YourServiceSubClassName
user	number or string	no	The user ID for which the service is started. The current user id is used by default	1006
foreground	boolean	no	Set it to true if your service must be started as foreground service.	false

mobile: stopService

Stops the given service intent.

Arguments

Name	Type	Required	Description	Example
intent	string	yes	The name of the service intent to stop. Only services in the app's under test scope could be stopped.	com.some.package.name/.YourServiceSubClassName
user	number or string	no	The user ID for which the service is started. The current user id is used by default	1006

mobile: getDeviceTime

Retrieves the current device's timestamp.

Arguments

Name	Type	Required	Description	Example
format	string	no	The set of format specifiers. Read https://momentjs.com/docs/ to get the full list of supported datetime format specifiers. The default format is YYYY-MM-DDTHH:mm:ssZ, which complies to ISO-8601	YYYY-MM-DDTHH:mm:ssZ

Returns

The device timestamp string formatted according to the given specifiers

mobile: setDate

Set the given date for a picker control. Invokes https://developer.android.com/reference/androidx/test/espresso/contrib/PickerActions#setdate under the hood.

Arguments

Name	Type	Required	Description	Example
year	int	yes	The year to set	2020
monthOfYear	int	yes	The number of the month to set	3
dayOfMonth	int	yes	The number of the day to set	20

mobile: setTime

Set the given time for a picker control. Invokes https://developer.android.com/reference/androidx/test/espresso/contrib/PickerActions#settime under the hood.

Arguments

Name	Type	Required	Description	Example
hours	int	yes	Hour to set in range 0..23	14
minutes	int	yes	Minute to set in range 0..59	15

mobile: flashElement

Highlights the given element in the UI by adding flashing to it

Arguments

Name	Type	Required	Description	Example
element	string	yes	UDID of the element to perform the action on.	123456-7890-3453-24234243
durationMillis	int	no	Duration of single flashing sequence, 30 ms by default	50
repeatCount	int	no	Count of repeats, 15 times by default	10

mobile: dismissAutofill

Dismisses autofill picker if it is visible on the screen.

mobile: backdoor

Gives a possibility to invoke methods from your application under test.

Arguments

Name	Type	Required	Description	Example
elementId	string	yes if target is set to element	UDID of the element to perform the action on.	123456-7890-3453-24234243
target	string	yes	Select a target for the backdoor mathod execution: activity, application, element	activity
methods	Array<Map>	yes	Methods chain to execute	See Backdoor Extension Usage

Returns

The result of the last method in the chain

mobile: uiautomator

Allows to execute a limited set of UiAutomator commands to allow out-of-app interactions with accessibility elements.

Arguments

Name	Type	Required	Description	Example
strategy	string	yes	UiAutomator element location strategy. The following strategies are supported: "clazz", "res", "text", "textContains", "textEndsWith", "textStartsWith", "desc", "descContains", "descEndsWith", "descStartsWith", "pkg"	desc
locator	string	yes	Valid UiObject2 locator value for the given strategy	'my description'
action	string	yes	The action name to perform on the found element. The following actions are supported: "click", "longClick", "getText", "getContentDescription", "getClassName", "getResourceName", "getVisibleBounds", "getVisibleCenter", "getApplicationPackage", "getChildCount", "clear", "isCheckable", "isChecked", "isClickable", "isEnabled", "isFocusable", "isFocused", "isLongClickable", "isScrollable", "isSelected"	isEnabled
index	int	no	If the given locator matches multiple elements then only the element located by this index will be selected for the interaction, otherwise the method will be applied to all found elements. Indexing starts from zero	1

Returns

The result of the selected action applied to found elements. If index is provided then the array will only contain one item. If the index is greater than the count of found elements then an exception will be thrown.

mobile: uiautomatorPageSource

Allows to retrieve accessibility elements hierarchy tree with UiAutomator framework. The extension calls dumpWindowHierarchy under the hood.

Returns

The UI accessibility hierarchy represented as XML document.

mobile: mobileWebAtoms

Allows to run a chain of Espresso web atoms on a web view element.

Arguments

Name	Type	Required	Description	Example
webviewEl	string	yes	The UDID of the destination web view element	123456-7890-3453-24234243
forceJavascriptEnabled	boolean	yes	If webview disables javascript then webatoms won't work. Setting this argument to true enforces javascript to be enabled.	true
methodChain	Array<Map>	yes	Chain of atoms to execute. Each item in the chain must have the following properties: name (must be one of WebInteraction action names) and atom. atom is a map with two entries: name (must be one of DriverAtoms method names) and args (must be an array of the corresponding method values).	[{"name": "methodName", "atom": {"name": "atomName", "args": ["arg1", "arg2", ...]}}, ...]

Returns

Chain items are executed sequentially and the next item is executed on the result of the previous item. The final result is returned to the caller.

mobile: registerIdlingResources

Registers one or more idling resources.

Arguments

Name	Type	Required	Description	Example
classNames	string	yes	Comma-separated list of idling resources class names. Each name must be a full-qualified java class name. Each class in the app source must implement a singleton pattern and have a static getInstance() method returning the class instance, which implements androidx.test.espresso.IdlingResource interface. Read Integrate Espresso Idling Resources in your app to build flexible UI tests for more details on how to design and use idling resources concept in Espresso.	io.appium.espressoserver.lib.MyIdlingResource

mobile: unregisterIdlingResources

Unregisters one or more idling resources.

Arguments

Name	Type	Required	Description	Example
classNames	string	yes	Comma-separated list of idling resources class names. Each name must be a full-qualified java class name. Each class in the app source must implement a singleton pattern and have a static getInstance() method returning the class instance, which implements androidx.test.espresso.IdlingResource interface. Read Integrate Espresso Idling Resources in your app to build flexible UI tests for more details on how to design and use idling resources concept in Espresso.	io.appium.espressoserver.lib.MyIdlingResource

mobile: listIdlingResources

Lists all the previously registered idling resources.

Returns

List of fully qualified class names of currently registered idling resources or an empty list if no resources have been registered yet.

Backdoor Extension Usage

Espresso driver allows to directly invoke a method from your application under test using mobile: backdoor extension. If target is set to application then methods will be invoked on the application class. If target is set to activity then methods will be invoked on the current application activity. If target is set to element then methods will be invoked on the selected view element. Only 'public' methods can be invoked ('open' modifier is necessary in Kotlin). The following primitive types are supported for method arguments: "int", "boolean", "byte", "short", "long", "float", "char". Object wrappers over primitive types with fully qualified names "java.lang.*" are also supported: "java.lang.CharSequence", "java.lang.String", "java.lang.Integer", "java.lang.Float", "java.lang.Double", "java.lang.Boolean", "java.lang.Long", "java.lang.Short", "java.lang.Character", etc.

For example, in the following arguments map

{
   "target": "activity",
   "methods":
   [
     {
       "name": "someMethod",
     },
     {
       "name": "anotherMethod",
       "args": [
         {"value": "foo", "type": "java.lang.CharSequence"},
         {"value": 1, "type": "int"}
       ]
     }
   ]
}

the anotherMethod will be called on the object returned by someMethod, which has no arguments and which was executed on the current activity instance. Also anotherMethod accepts to arguments of type java.lang.CharSequence and int. The result of anotherMethod will be serialized and returned to the client.

Troubleshooting

• If there are ever problems starting a session, try setting the capability forceEspressoRebuild=true and retrying. This will rebuild a fresh Espresso Server APK. If the session is successfull, set it back to false so that it doesn't re-install on every single test.
• Espresso requires the debug APK and app-under-test APK (AUT) to have the same signature. It automatically signs the AUT with the io.appium.espressoserver.test signature. This may have problems if you're using an outdated Android SDK tools and/or an outdated Java version.
• If you experience session startup failures due to exceptions similar to Resources$NotFoundException then try to adjust your ProGuard rules:

  -dontwarn com.google.android.material.**
  -keep class com.google.android.material.** { *; }
  
  -dontwarn androidx.**
  -keep class androidx.** { *; }
  -keep interface androidx.** { *; }
  
  -dontwarn android.support.v4.**
  -keep class android.support.v4.** { *; }
  
  -dontwarn android.support.v7.**
  -keep class android.support.v7.** { *; }
  

  Please read #449 for more details on this topic.

Contributing

Contents of Repo

• espresso-server/: Android Java code that gets built into a test apk. The test apk runs a NanoHTTP server that implements the WebDriver protocol.
• lib/: NodeJS code that constitutes the Appium driver, which is responsible for handling capabilities and starting up the Espresso instrumentation context. Once the Espresso server is up, this code is responsible for proxying user requests to it.

Running

• To build the Espresso server and the NodeJS code, run npm run build
• To just build the Espresso server, run npm run build:server or cd espresso-server && ./gradlew clean assembleDebug assembleAndroidTest. The server can also be built from Android Studio.
  • To build the espresso server for a custom target package ./gradlew -PappiumTargetPackage=io.appium.android.apis assembleAndroidTest
• To just build NodeJS code, run gulp transpile

Tests

• Espresso server unit tests are located at io.appium.espressoserver.test and can be run in Android Studio
• NodeJS unit tests are run with npm run test
• End-to-end tests are run with npm run e2e-test (remember to run npm run build before running this command so that it has up-to-date Espresso Server and NodeJS code)