cli

A minimal, command-oriented CLI package.

Features

• Very small, simple API.
• Support for POSIX flags.
• Only external dependency is spf13/pflag.
• Subcommands and subcommand aliases.
• Auto-generated help.

Install

go get -u go.coder.com/cli

Examples

See examples/ for more.

Simple CLI

package main

import (
    "fmt"

    "github.com/spf13/pflag"
    "go.coder.com/cli"
)

type cmd struct {
    verbose bool
}

func (c *cmd) Run(fl *pflag.FlagSet) {
    if c.verbose {
        fmt.Println("verbose enabled")
    }
    fmt.Println("we run")
}

func (c *cmd) Spec() cli.CommandSpec {
    return cli.CommandSpec{
        Name:  "simple-example",
        Usage: "[flags]",
        Desc:  `This is a simple example of the cli package.`,
    }
}

func (c *cmd) RegisterFlags(fl *pflag.FlagSet) {
    fl.BoolVar(&c.verbose, "v", false, "sets verbose mode")
}

func main() {
    cli.RunRoot(&cmd{})
}

renders a help like

Usage: simple-example [flags]

This is a simple example of the cli package.

simple-example flags:
	-v	sets verbose mode	(false)

Subcommands

package main

import (
    "fmt"

    "github.com/spf13/pflag"
    "go.coder.com/cli"
)

type subcmd struct {
}

func (c *subcmd) Run(fl *pflag.FlagSet) {
    fmt.Println("subcommand invoked")
}

func (c *subcmd) Spec() cli.CommandSpec {
    return cli.CommandSpec{
        Name:  "sub",
        Usage: "",
        Aliases: []string{"s"},
        Desc:  `This is a simple subcommand.`,
    }
}

type cmd struct {
}

func (c *cmd) Run(fl *pflag.FlagSet) {
    // This root command has no default action, so print the help.
    fl.Usage()
}

func (c *cmd) Spec() cli.CommandSpec {
    return cli.CommandSpec{
        Name:  "subcommand",
        Usage: "[flags]",
        Desc:  `This is a simple example of subcommands.`,
    }
}

func (c *cmd) Subcommands() []cli.Command {
    return []cli.Command{
        &subcmd{},
    }
}

func main() {
    cli.RunRoot(&cmd{})
}

renders a help like

Usage: subcommand [flags]

This is a simple example of subcommands.

Commands:
	s, sub  - This is a simple subcommand.