To be able to run modules from the Fuchsia command line, you need to select a Fuchsia build configuration that does not start basemgr and shows a graphical session shell right at boot time. You can use for example the test_modular configuration in fx set and build as follows:
fx set x64 --packages peridot/packages/products/test_modular fx full-build
If fx is not in your PATH, you should add .jiri_root/bin to your PATH.
An application can be run as a module in a story using dev_session_shell. For example (from test runner invocation):
basemgr --test --account_provider=dev_token_manager \ --base_shell=dev_base_shell --session_shell=dev_session_shell \ --story_shell=dev_story_shell \ --session_shell_args=--root_module=parent_child_test_parent_module
dev_base_shell is used to log in a dummy user directly without going through an authentication dialog. dev_session_shell runs the module given to it in --session_shell_args in a story.
The flags --session_shell and --session_shell_args are read by basemgr. The value of --session_shell is the application that is run as the session shell. The value of --session_shell_args is a comma separated list of arguments passed to the session shell application. In this example, these arguments are in turn more flags. Commas inside the value of such arguments are escaped by backslashes. The value of --root_module selects the module to run. The value of --root_link is a JSON representation of the initial data the module is started with.
The user name provided by dev_base_shell can be set with --user. It is used by basemgr when opening the Ledger. However, the --user parameter does not work for userpicker_base_shell, because that shell displays a GUI to select the user to login.
Applications are generally referenced by URLs. If the application binary is in a location where application manager expects it, e.g. /pkgfs/packages, the URL can be relative. Otherwise, the URL should be relative with an absolute path, or absolute altogether.
