Built-in commands

ZIO CLI automatically constructs some common commands:

• --help or -h shows a description of the CLI's commands.
• --wizard executes wizard mode.
• --shell-completion-index, --shell-completion-script and --shell-type are used for Bash and Zsh Completion.

These commands are automatically generated also for all subcommands of a command.

import zio.cli._

val cliApp = CliApp.make(
    name = "SampleCliApp",
    version = "0.0.1",
    summary = HelpDoc.Span.text("Sample CLI application"),
    command = Command("command")
) {
    case _ => ???
}

// Prints help of the cliApp command
cliApp.run(List("-h"))

// Prints help of subcommand
cliApp.run(List("subcommand", "-h"))

Examples

import zio.cli._
import java.nio.file.Path

// Construction of basic commands and HelpDoc
val helpGit = "This is command git."
val helpGitAdd = "Stages changes in the working repository."
val helpGitClone = "Creates a copy of an existing repository."

val git: Command[Unit] = Command("git").withHelp(helpGit)
val gitAdd: Command[Unit] = Command("add").withHelp(helpGitAdd)
val gitClone: Command[Path] = Command("clone", Options.directory("directory")).withHelp(helpGitClone)

// Adds subcommands add and clone to command git
val finalCommand: Command[Any] = git.subcommands(gitAdd, gitClone)

Help

The output produced by command --help or -h is

USAGE

  $ git <command>

DESCRIPTION

  This is command git.

COMMANDS

  - add                          Stages changes in the working repository.
  - clone --directory directory  Creates a copy of an existing repository.

If we desire to consult the help of a subcommand, like clone, we would get the following.

USAGE

  $ git clone --directory directory

DESCRIPTION

  Creates a copy of an existing repository.

OPTIONS

  --directory directory
    A directory.

Wizard

Wizard mode allows to construct a command by choosing between parameters offered by the application. The output would be the following.

Command(add|clone): 

If we input clone, we will get:

--directory (directory):