Grumble - A powerful modern CLI and SHELL
There are a handful of powerful go CLI libraries available (spf13/cobra, urfave/cli). However sometimes an integrated shell interface is a great and useful extension for the actual application. This library offers a simple API to create powerful CLI applications and automatically starts an integrated interactive shell, if the application is started without any command arguments.
Hint: We do not guarantee 100% backwards compatiblity between minor versions (1.x). However, the API is mostly stable and should not change much.
Introduction
Create a grumble APP.
var app = grumble.New(&grumble.Config{
Name: "app",
Description: "short app description",
Flags: func(f *grumble.Flags) {
f.String("d", "directory", "DEFAULT", "set an alternative directory path")
f.Bool("v", "verbose", false, "enable verbose mode")
},
})
Register a top-level command. Note: Sub commands are also supported...
app.AddCommand(&grumble.Command{
Name: "daemon",
Help: "run the daemon",
Aliases: []string{"run"},
Flags: func(f *grumble.Flags) {
f.Duration("t", "timeout", time.Second, "timeout duration")
},
Args: func(a *grumble.Args) {
a.String("service", "which service to start", grumble.Default("server"))
},
Run: func(c *grumble.Context) error {
// Parent Flags.
c.App.Println("directory:", c.Flags.String("directory"))
c.App.Println("verbose:", c.Flags.Bool("verbose"))
// Flags.
c.App.Println("timeout:", c.Flags.Duration("timeout"))
// Args.
c.App.Println("service:", c.Args.String("service"))
return nil
},
})
Run the application.
err := app.Run()
Or use the builtin grumble.Main function to handle errors automatically.
func main() {
grumble.Main(app)
}
Shell Multiline Input
Builtin support for multiple lines.
>>> This is \
... a multi line \
... command
Samples
Check out the sample directory for some detailed examples.
The grml project uses grumble.
Additional Useful Packages
Credits
This project is based on ideas from the great ishell library.
License
MIT
