Advanced CLI with cobra and viper

Context

For production‑grade CLI tools, use cobra (commands, subcommands, help) and viper (configuration from flags, env, files). Cobra is used by Kubernetes, Docker, GitHub CLI, etc.

Example

A simple cobra app with one command.

Code example

package main

import (
    "fmt"
    "github.com/spf13/cobra"
)

func main() {
    var name string
    rootCmd := &cobra.Command{
        Use:   "greet",
        Short: "Greets someone",
        Run: func(cmd *cobra.Command, args []string) {
            fmt.Printf("Hello, %s!\n", name)
        },
    }
    rootCmd.Flags().StringVarP(&name, "name", "n", "World", "Name to greet")
    rootCmd.Execute()
}

Output

Hello, Alice!

Useful links

• Cobra documentation
• Viper documentation