Using the devicefarm-cli tool in custom test environments

The test host uses a standardized version management tool called devicefarm-cli to select software versions. This tool is separate from the AWS CLI and only available on the Device Farm test host. With devicefarm-cli, you can switch to any pre-installed software version on the test host. This provides a straightforward way to maintain your Device Farm test spec file over time and gives you a predictable mechanism to upgrade software versions in the future.

Important

This command line tool is not available on legacy iOS hosts. For more information, see the topic on the Legacy iOS test host.

The snippet below shows the help page of devicefarm-cli:

$ devicefarm-cli help
 Usage: devicefarm-cli COMMAND [ARGS]
     
     Commands:
         help                         Prints this usage message.
         list                         Lists all versions of software configurable
                                      via this CLI.
         use <software> <version>     Configures the software for usage within the
                                      current shell's environment.

Let's review a couple of examples using devicefarm-cli. To use the tool to change the Python version from 3.10 to 3.9 in your test spec file, run the following commands:

$ python --version
Python 3.10.12
$ devicefarm-cli use python 3.9
$ python --version
Python 3.9.17

To change the Appium version from 1 to 2 :

$ appium --version
1.22.3
$ devicefarm-cli use appium 2
$ appium --version
2.1.2

Tip

Note that when you select a software version, devicefarm-cli also switches the supporting tools for those languages, such as pip for Python and npm for NodeJS.

For more information about the preinstalled software on the test host, see Supported software within custom test environments.