Desired capabilities

Desired capabilities is a JSON object (a set of keys and values) sent by the client to the server. It describes the capabilities for the automation session in which we are interested.

Let's discuss the capabilities one by one; first, we will see the Appium server's capabilities:

We need to import "import org.openqa.Selenium.remote.DesiredCapabilities" library for Java to work with the desired capabilities.

Capability	Explanation
automationName	This capability is used to define the automation engine. If you want to work with an Android SDK version less than 17, then you need to define the value as Selendroid; otherwise, the capability takes the default value as Appium. Let's see how we can implement it practically: DesiredCapabilities caps = new DesiredCapabilities(); // creating an object caps.setCapability("automationName","Selendroid"); // to set capability value We can also set the capabilities using Appium's client library. For this, users need to import "import io.appium.java_client.remote.MobileCapabilityType" library: caps.setCapability(MobileCapabilityType.AUTOMATION_NAME,"Selendroid"); There's no need to use this capability in the case of iOS.
platformName	It is used to set the mobile OS platform. It uses the value as iOS, Android, or FirefoxOS: caps.setCapability("platformName","Android"); In case of the Appium client library, you can use this: caps.setCapability(MobileCapabilityType.PLATFORM_NAME, "Android");
platformVersion	To set the mobile OS version, for example, 7.1, 4.4.4, use the following command: caps.setCapability("platformVersion","4.4.4"); Alternatively, you can use the following command as well: caps.setCapability(MobileCapabilityType.PLATFORM_VERSION, "4.4.4");
deviceName	We can define the type of mobile device or emulator to use, using the following command, for example, iPhone Simulator, iPad Simulator, iPhone Retina 4-inch, Android Emulator, Moto x, Nexus 5, and so on: caps.setCapability("deviceName", "Nexus 5"); You can use the following command as well: caps.setCapability(MobileCapabilityType.DEVICE_NAME,"Nexus 5");
app	We can add the absolute local path or remote HTTP URL of the .ipa,.apk, or .zip file. Appium will install the app binary on the appropriate device first. Note that in the case of Android, if you specify the appPackage and appActivity (both the capabilities will be discussed later in this section) capabilities, then this capability shown here is not required: caps.setCapability("app","/apps/demo/demo.apk or http://app.com/app.ipa"); Alternatively, you can use the following command: caps.setCapability(MobileCapabilityType.APP,"/apps/demo/demo.apk or http://app.com/app.ipa");
browserName	If you want to automate mobile web applications, then you have to use this capability to define the browser. For Safari on iOS, you can use this: caps.setCapability("browserName", "Safari"); Also, you can use the following command: caps.setCapability(MobileCapabilityType.BROWSER_NAME, "Safari"); For Chrome on Android, you can use this: caps.setCapability("browserName", "Chrome"); Alternatively, you can use the following command: caps.setCapability(MobileCapabilityType.BROWSER_NAME, "Chrome");
newCommandTimeout	To end the session, Appium will wait for a few seconds for a new command from the client before assuming that the client quit. The default value is 60. To set this time, you can use the following command: caps.setCapability("newCommandTimeout", "30"); You can also use this command to end the session: caps.setCapability(MobileCapabilityType.NEW_COMMAND_TIMEOUT,"30");
autoLaunch	This capability is used to install and launch the app automatically. The default value is set to true. You can set the capability with the following command: caps.setCapability("autoLaunch","false");
language	This is used to set the language on the simulator/emulator, for example, fr, es, and so on. The following command will work only on the simulator/emulator: caps.setCapability("language","fr");
locale	This is used to set the locale for the simulator/emulator, for example, fr_CA, tr_TR, and so on: caps.setCapability("locale","fr_CA");
udid	A unique device identifier (udid) is basically used to identify iOS physical device. It is a 40 character long value (for example, 1be204387fc072g1be204387fc072g4387fc072g). This capability is used when you are automating apps on iOS physical device. We can easily get the device udid from iTunes, by clicking on Serial Number: caps.setCapability("udid", "1be204387fc072g1be204387fc072g4387fc072g");
orientation	This is used to start in a certain orientation in simulator/emulator only, for example, LANDSCAPE or PORTRAIT: caps.setCapability("orientation", "PORTRAIT");
autoWebview	If you are automating hybrid apps and want to move directly into the Webview context, then you can set it by using this capability; the default value is false: caps.setCapability("autoWebview", "true");
noReset	This capability is used to reset the app's state before the session starts; the default value is false: caps.setCapability("noReset"-," true");
fullReset	In iOS, this will delete the entire simulator folder. In Android, you can reset the app's state by uninstalling the app instead of clearing the app data; also, it will remove the app after the session is complete. The default value is false. The following is the command for fullReset: caps.setCapability("fullReset", "true");

Android capabilities

Now, let's discuss the Android capabilities, as shown in the following table:

Capability	Explanation
appPackage	This capability is for the Java package of the Android app that you want to run, for example, com.android.calculator2, com.android.settings, and so on: caps.setCapability("appPackage", "com.android.calculator2"); Alternatively, you can use this command: caps.setCapability(MobileCapabilityType.APP_PACKAGE, "com.android.calculator2");
appActivity	By using this capability, you can specify the Android activity that you want to launch from your package, for example, MainActivity, .Settings, com.android.calculator2.Calculator, and so on: caps.setCapability("appActivity", "com.android.calculator2.Calculator"); You can also use the following command: caps.setCapability(MobileCapabilityType.APP_ACTIVITY, "com.android.calculator2.Calculator");
appWaitActivity	Android activity for which the user wants to wait can be defined using this capability: caps.setCapability("appWaitActivity","com.android.calculator2.Calculator"); Alternatively, you can also use this command: caps.setCapability(MobileCapabilityType.APP_WAIT_ACTIVITY,"com.android.calculator2.Calculator");
appWaitPackage	The Java package of the Android app you want to wait for can be defined using the following capability, for example, com.example.android.myApp, com.android.settings, and so on: caps.setCapability("appWaitPackage","com.example.android.myApp");
deviceReadyTimeout	You can set the timeout (in seconds) while waiting for the device to be ready, as follows; the default value is 5 seconds: caps.setCapability("deviceReadyTimeout","10"); Alternatively, you can also use this command: caps.setCapability(MobileCapabilityType.DEVICE_READY_TIMEOUT,"10");
enablePerformanceLogging	You can enable the Chrome driver's performance logging by the use of this capability. It will enable logging only for Chrome and web view; the default value is false: caps.setCapability("enablePerformanceLogging", "true");
androidDeviceReadyTimeout	To set the timeout in seconds for a device to become ready after booting, you can use the following capability: caps.setCapability("androidDeviceReadyTimeout","20");
androidDeviceSocket	This capability is used to set DevTools socket name. It is only needed when an app is a Chromium-embedding browser. The socket is opened by the browser and the ChromeDriver connects to it as a DevTools client, for example, chrome_DevTools_remote: caps.setCapability("androidDeviceSocket","chrome_DevTools_remote");
Avd	Using this capability, you can specify the name of avd that you want to launch, for example, AVD_NEXUS_5: caps.setCapability("avd","AVD_NEXUS_5");
avdLaunchTimeout	This capability will help you define how long you need to wait (in milliseconds) for an avd to launch and connect to the Android Debug Bridge (ADB) (the default value is 120000): caps.setCapability("avdLaunchTimeout","230000");
avdReadyTimeout	You can specify the wait time (in milliseconds) for an avd to finish its boot animations using the following capability; the default wait timeout is 120000: caps.setCapability("avdReadyTimeout","240000");
avdArgs	To pass the additional emulator arguments when launching an avd, use the following capability, for example, netfast: caps.setCapability("avdArgs","netfast");
chromedriverExecutable	You can give the absolute local path to the WebDriver executable (if the Chromium embedder provides its own WebDriver, it should be used instead of the original ChromeDriver bundled with Appium) using the following capability: caps.setCapability("chromedriverExecutable","/abs/path/to/webdriver");
autoWebviewTimeout	The following capability allows you to set the time (in milliseconds) for which you need to wait for the Webview context to become active; the default value is 2000: caps.setCapability("autoWebviewTimeout","3000");
intentAction	Intent action is basically used to start an activity, as shown in the following code. The default value is android.intent.action.MAIN. For example, android.intent.action.MAIN, android.intent.action.VIEW, and so on: caps.setCapability("intentAction","android.intent.action.VIEW");
intentCategory	This provides the intent category that will be used to start the activity (the default is android.intent.category.LAUNCHER), for example, android.intent.category.LAUNCHER, android.intent.category.APP_CONTACTS: caps.setCapability("intentCategory","android.intent.category.APP_CONTACTS");
intentFlags	Flags are used to start an activity (the default is 0x10200000), for example, 0x10200000: caps.setCapability("intentFlags","0x10200000");
unicodeKeyboard	You can enable Unicode input by using the following code; the default value is false: caps.setCapability("unicodeKeyboard","true");
resetKeyboard	You can reset the keyboard to its original state by using this capability. The default value is false: caps.setCapability("resetKeyboard","true");

iOS capabilities

Let's discuss the iOS capabilities, as shown in the following table:

Capability	Explanation
calendarFormat	This is used to set the calendar format for the iOS simulator. It applies only to a simulator, for example, Gregorian: caps.setCapability("calendarFormat"," Gregorian");
bundleId	BundleId is basically used to start an app on a real device or to use other apps that require the bundleId during the test startup, for example, io.appium.TestApp: caps.setCapability("bundleId"," io.appium.TestApp");
launchTimeout	This is used to specify the amount of time (in millisecond) you need to wait for Instruments before assuming that it hung and the session failed. This can be done using the following command: caps.setCapability("launchTimeout","30000");
locationServicesEnabled	This capability is used to enable location services. You can apply it only on a simulator; you can give the Boolean value, as follows: caps.setCapability("locationServicesEnabled","false");
locationServicesAuthorized	If you want to use this capability, you must provide the bundleId by using the bundleId capability. You can use this capability on a simulator. After setting this, the location services alert doesn't pop up. The default is the current simulator setting and its value is false: caps.setCapability("locationServicesAuthorized","true");
autoAcceptAlerts	Using this capability, you can accept privacy permission alerts automatically, such as location, contacts, photos, and so on, if they arise; the default value is false: caps.setCapability("autoAcceptAlerts","true");
nativeInstrumentsLib	You can use the native instruments library by setting up this capability: caps.setCapability("nativeInstrumentsLib","true");
nativeWebTap	This can be used to enable real web taps in Safari, which are non-JavaScript based. The default value is false. Let me warn you that this might not perfectly deal with an element; it depends on the viewport's size/ratio: caps.setCapability("nativeWebTap","false");
safariAllowPopups	You can use this capability on a simulator only. It allows JavaScript to open new windows in Safari. The default is the current simulator setting. To do this, you can use the following command: caps.setCapability("safariAllowPopups","false");
safariIgnoreFraudWarning	This capability can be used only on a simulator. It prohibits Safari from displaying a fraudulent website warning. The default value is the current simulator setting, as follows: caps.setCapability("safariIgnoreFraudWarning","false");
safariOpenLinksInBackground	This capability enables Safari to open links in new windows; the default keeps the current simulator settings: caps.setCapability("safariOpenLinksInBackground","true");
keepKeyChains	Whether you need to keep keychains (Library/Keychains) when an Appium session is started/finished can be defined using this capability. You can apply it on a simulator, as follows: caps.setCapability("keepKeyChains","true");
processArguments	This capability allows you to pass arguments while AUT using instruments, for example, myflag: caps.setCapability("processArguments","myflag");
interKeyDelay	You can delay the keystrokes sent to an element when typing uses this capability. It takes the value in milliseconds: caps.setCapability("interKeyDelay","100");

We have seen all the desired capabilities that are used in Appium. Now, we will talk in brief about the Appium server and its client library.