CLI

Build beautiful CLIs in Go. A simpler alternative to kingpin.

Features

• Type-safe, fluent API
• Flag, command and argument support
• Required and optional parameters
• Built entirely on the flag package the standard library
• Supports both space-based and colon-based subcommands (e.g. controller new & controller:new)
• SIGINT context cancellation out-of-the-box
• Custom help messages
• Built-in tab completion with complete -o nospace -C <cmd> <cmd>
• Respects NO_COLOR

Install

go get -u github.com/livebud/cli

Example

package main

import (
  "context"
  "fmt"
  "os"

  "github.com/livebud/cli"
)

func main() {
  flag := new(Flag)
  cli := cli.New("app", "your awesome cli").Writer(os.Stdout)
  cli.Flag("log", "log level").Short('L').String(&flag.Log).Default("info")
  cli.Flag("embed", "embed the code").Bool(&flag.Embed).Default(false)

  { // new <dir>
    cmd := &New{Flag: flag}
    cli := cli.Command("new", "create a new project")
    cli.Arg("dir").String(&cmd.Dir)
    cli.Run(cmd.Run)
  }

  ctx := context.Background()
  if err := cli.Parse(ctx, os.Args[1:]...); err != nil {
    fmt.Fprintln(os.Stderr, err)
    os.Exit(1)
  }
}

type Flag struct {
  Log   string
  Embed bool
}

type New struct {
  Flag *Flag
  Dir  string
}

// Run new
func (n *New) Run(ctx context.Context) error {
  return nil
}

Contributing

First, clone the repo:

git clone https://github.com/livebud/cli
cd cli

Next, install dependencies:

go mod tidy

Finally, try running the tests:

go test ./...

License

MIT