Environment Variables in Test

Important

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When testing, it's often helpful to launch your application or test runner with custom environment variables set. For example, environment variables can be used to control the behavior of your application or provide tests with sign-in information.

For most frameworks, useful environment variables are available within the test, application, or both. You can set additional environment variables via the App Center CLI.

Support by framework

In App Center, some frameworks and platform combinations support setting and using custom environment variables as well as using variables that are made available to your application and tests automatically (for example RUNNING_IN_APP_CENTER and APP_CENTER_TEST).

This table lists environment variables supported for each framework or platform:

Framework	Test Environment Variables	Application Environment Variables
Appium	Available	Not Available
Calabash	Available	Available in iOS only
Espresso	Available	Available
Xamarin.UITest	Available	Available in iOS only
XCUITest	Not Available	Not Available

Note

In Espresso tests and Android applications, variables are available in the InstrumentationRegistry since Android doesn't support environment variables.

Environment variables available in your application

For supported frameworks, these environment variables are available within the application:

Environment Variable	Description
RUNNING_IN_APP_CENTER	Set to 1 when the device is running in App Center Test

Environment variables available in your tests

For supported frameworks, these environment variables are available within the tests:

Environment Variable	Description
APP_CENTER_TEST	Set to 1 when your tests run in App Center Test.
XTC_APP_ENDPOINT	Address of a secure port on the device that allows other services to communicate with the application. Used by applications that embed their own HTTP servers in an application and need to interact with the app outside of the test framework. (Android Only). Example: http://devicehost151.prod:37777/proxy2/token-c059c5c6-37cc-4400-9038-96d1d342ed6e/
XTC_DEVICE	Combines the operating system name and the device name. Example: Google Pixel 2 XL (8.1.0)
XTC_DEVICE_INDEX	A string in the range of 0 to N-1, where N is the number of devices the test is run on. Used in situations where the same test is being run in parallel on multiple devices. XTC_DEVICE_INDEX is unique for each test run for each device. For additional discussion, see: Handling Concurrent Database Changes During Tests.
XTC_DEVICE_NAME	Name of the device running the test. Example: Google Pixel 2 XL
XTC_DEVICE_OS	Name of the operating system for the device running the test. Example: 8.1.0
XTC_LANG	Language code used to run the test. Example: en
XTC_PLATFORM	Platform under test, either android or ios.

Setting additional environment variables

When you upload your tests to App Center with the CLI, you can request environment variables be set using the --test-parameter option. Environment variables can be set for test runner and for your application (the application under test or AUT).

Note

See Support by framework for details of which frameworks support test and application variables in App Center Test.

Environment variables for your tests

$ appcenter test run < > \
  < args > \
  --test-parameter "test_env=USERNAME=clever_user@example.com" \
  --test-parameter "test_env=PASSWORD=pa$$w0rd" \
  --test-parameter "test_env=TWO_FACTOR_URL=https://staging.example.com/test-2FA" \
  --test-parameter "test_env=UPGRADE_PURCHASED=0"

Environment variables for your application

$ appcenter test run < > \
  < args > \
  --test-parameter "app_env=VERBOSE_LOGGING=1" \
  --test-parameter "app_env=CONTENT_SERVER=staging.example.com \
  --test-parameter "app_env=API_LEVEL=3.2" \
  --test-parameter "app_env=UPGRADE_PURCHASED=0"

Using environment variables in your tests

Sample Appium test code:

The following code snippet shows how to access environment variables in App Center Test using Appium

String appCenterTest = System.getenv("APP_CENTER_TEST");

Sample Calabash test code:

The following code snippet shows how to access environment variables in App Center Test using Calabash

app_center_test = ENV["APP_CENTER_TEST"]

Sample Espresso test code

Since Android doesn't support environment variables, App Center Test sets InstrumentationRegistry values instead for Espresso. The following code snippet shows how to access the InstrumentationRegistry values.

String appCenterTest = InstrumentationRegistry.getArguments().getString("APP_CENTER_TEST");

Sample Xamarin.UITest test code

The following code snippet shows how to access environment variables in App Center Test using Xamarin.UITest:

string appCenterTest = Environment.GetEnvironmentVariable("APP_CENTER_TEST");

Using environment variables in your application

Sample native Android application code

Note

See Support by framework for details of which frameworks support application variables in App Center Test.

Since Android doesn't support environment variables, App Center Test sets InstrumentationRegistry values instead. The following code snippet shows how to access the InstrumentationRegistry values.

String runningInAppCenter = InstrumentationRegistry.getArguments().getString("RUNNING_IN_APP_CENTER");

Sample native iOS application code

Note

See Support by framework for details of which frameworks support application variables in App Center Test.

Native iOS applications access environment variables through the NSProcessInfo API.

[[NSProcessInfo processInfo] environment]["RUNNING_IN_APP_CENTER"]

ProcessInfo.processInfo.environment["RUNNING_IN_APP_CENTER"]

Getting help

You can contact support in the App Center portal. In the upper right corner of screen, select the Help (?) menu, then choose 'Contact support'. Our dedicated support team will respond to your questions.

If you want help with a test run, navigate to the test run in question and copy the URL from your browser and paste it into the support conversation. A test run URL looks like something like https://appcenter.ms/orgs/OrgName/apps/App-Name/test/runs/77a1c67e-2cfb-4bbd-a75a-eb2b4fd0a747.