Command Line Interface Reference

May 29, 2026 ยท View on GitHub

Launchpad root command

Launchpad is activated by using the launchpad command and provides a command-line interface to start, list, and explain the applications available within the image.

Both for Pharo and VAST Platform the command must be passed after the image parameters:

pharo App.image launchpad <arguments>

vast/bin/esnx \
    -platform UNIX \
    -no_break \
    -iApp.image \
    -ini:esnx.ini \
    launchpad <arguments>

For GemStone/S 64 the command must be passed after the topaz arguments:

topaz -l -- launchpad <arguments>

and starting the command line handler by evaluating:

  LaunchpadCommandLineHandler activateWith:
    (CommandLineArguments new copyAfter: '--')

For the sake of simplicity, from now on we will omit in the examples the VM and image parameters:

launchpad [--version] [--help|-h] <command>

launchpad options

  • version Print the version and exit.

    $ launchpad --version
Launchpad [v4.0.0]

  • help, h Print the help message and exit.

    $ launchpad -h
NAME
              launchpad - A minimal application launcher
SYNOPSYS
              launchpad [--version] [--help|-h] <command>
DESCRIPTION
              A command-line interface to start, list, and explain the
              applications available within the image.
OPTIONS
              --version
                      Print the version and exit.
              -h, --help
                      Print this help message and exit.
COMMANDS
              start
                      Start the selected application
              list
                      List available applications
              explain
                      Give details about the selected application

launchpad sub-commands

  • list List available applications
  • explain Give details about the selected application
  • start Start the selected application

Launchpad list

The list sub-command will list the available applications within the image.

launchpad list [--verbose|-v] [--help|-h]

The applications listed are dependent on the image contents. Using an image with the Examples group loaded will produce:

$ launchpad list
broken greeter

list options

  • verbose,v Produce more verbose output.

    $ launchpad list -v
broken v0.0.1 A broken application
greeter v1.0.0 A greetings application

  • help,h Print the help message and exit.

    $ launchpad list -h
NAME
              launchpad-list - List available applications
SYNOPSYS
              launchpad list [--verbose|-v] [--help|-h]
DESCRIPTION
              Lists the available applications contained in the image.
OPTIONS
              -v, --verbose
                      Produce more verbose output.
              -h, --help
                      Print this help message and exit.

Launchpad explain

The explain sub-command will give details about the selected application, including the description, version, supported parameters, command-line options and environment variables.

launchpad explain [--help|-h] <app>

This sub-command requires a valid <app> handle to be provided, so it will know which application is needing explanation. The valid application handles can be obtained by using the list command.

$ launchpad explain greeter
NAME
                greeter [v1.0.0] - A greetings application
SYNOPSYS
                greeter --name=<name> [--title=<title>]
PARAMETERS
                --name=<name>
                        The name of the user to greet.
                --title=<title>
                        The title of the user to greet. Defaults to nothing.
ENVIRONMENT
                NAME
                        The name of the user to greet.
                TITLE
                        The title of the user to greet. Defaults to nothing.

Failing to provide an app handler, or providing and invalid one will result in an error:

$ launchpad explain
2021-11-16T11:32:57-03:00 [ERROR] Missing application name or option.

$ launchpad explain bad
2021-11-16T11:42:22-03:00 [ERROR] explain unknown application: bad

explain options

  • help,h Print the help message and exit.

    $ launchpad explain -h
NAME
              launchpad-explain - Give details about the selected application
SYNOPSYS
              launchpad explain [--help|-h] <app>
DESCRIPTION
              Give details about the application selected via <app> including
              its configuration options.
OPTIONS
              -h, --help
                      Print this help message and exit.

Launchpad start

The start sub-command will start the selected application.

launchpad start [--help|-h] [--debug-mode] [--settings-file=<filename>]
                [--enable-tcp-command-server=<listeningPort>]
                [--enable-structured-logging]
                [--dry-run]
                <app> [<parameters>]

This sub-command requires a valid <app> handle to be provided, so it will know which application to start. The valid application handles can be obtained by using the list command. Once an application is started the control is passed to it to perform whatever is intended.

$ launchpad start greeter --name=John
  [INFO] Obtaining configuration...
  [WARNING] "Title" parameter not provided. Using default.
  [INFO] Name: John
  [INFO] Title:
  [INFO] Obtaining configuration... [DONE]
Hi John!

Failing to provide an app handler, or providing and invalid one will result in an error:

$ launchpad start
2021-11-16T11:55:48-03:00 [ERROR] Missing application name or option.

$ launchpad start bad
2021-11-16T11:56:45-03:00 [ERROR] start unknown application: bad

Failing to provide one of the mandatory parameters of the application will also produce an error:

$ launchpad start greeter
  [INFO] Obtaining configuration...
  [ERROR] "Name" parameter not provided. You must provide one.

start options

  • help, h Print the help message and exit.

    $ launchpad start -h
NAME
              launchpad-start - Start the selected application
SYNOPSYS
              launchpad start [--help|-h] [--debug-mode]
                [--settings-file=<filename>] [--enable-structured-logging]
                [--enable-tcp-command-server=<listeningPort>]
                [--dry-run] <app> [<parameters>]
DESCRIPTION
              Start the application selected via <app>.

              Application configuration is made by the command-line via
              <parameters>, using environment variables or settings files.

              Execute launchpad explain <app> to get a list of valid
              configuration parameters.
OPTIONS
              -h, --help
                      Print this help message and exit.
              --debug-mode
                      Enable the debugging mode. The image will not quit on
                      unexpected errors. This configuration can be used in
                      the application to improve the debugging experience.
              --settings-file=<filename>
                      Provide application configuration via a settings file.
                      This option can occur several times to configure more
                      than one settings file. Supported file settings formats
                      are INI and JSON.
              --dry-run
                      Perform a dry run of the application.
                      All the configuration will be loaded (and validated),
                      but the application will not start.

  • debug-mode Enable the debugging mode.

  • settings-file=<filename> Provide application configuration via a settings file. This option can occur several times to configure more than one settings file.

    $ launchpad start --settings-file=names.json --settings-file=titles.ini greeter
  [INFO] Obtaining configuration...
  [INFO] Name: DJ
  [INFO] Title: Mr.
  [INFO] Obtaining configuration... [DONE]
Hi Mr. DJ!

    For details over the available configuration formats take a look at the configuration providers reference.

  • --enable-tcp-command-server=<listeningPort> Enable a TCP command server. This can be used to send commands controlling the application using a TCP port.

  • --enable-structured-logging Enable structured logging. When enabled the log will be emitted in JSON format.

  • --dry-run Perform a dry run of the application. All the configuration will be loaded (and validated), but the application will not start.