CLI Tool Examples

This page contains examples of using the CLI tool to generate CLI applications.

Example 1: Simple Greeting CLI

Generate a simple CLI that greets users:

cli init --name greet --type single

Interactive prompts:

• Project name: greet
• Usage: A simple greeting CLI
• Version: 0.1.0
• CLI type: single
• Add flag: name (String, required)
• Add flag: formal (Bool, default: false)

Generated code will include:

app.Command(func(ctx *cli.Context) error {
    name := ctx.String("name")
    formal := ctx.Bool("formal")
    
    if formal {
        fmt.Printf("Good day, %s!\n", name)
    } else {
        fmt.Printf("Hello, %s!\n", name)
    }
    return nil
})

Usage:

go run main.go --name "Alice"
go run main.go --name "Bob" --formal

Example 2: Todo List CLI

Generate a multiple commands CLI for managing todos:

cli init --name todo --type multiple

Add commands:

1. list command

   • Flag: --all (Bool) - Show all todos including completed
   • Flag: --limit (Int) - Limit number of results

2. add command

   • Flag: --title (String, required) - Todo title
   • Flag: --priority (String) - Priority level

3. complete command

   • Flag: --id (Int, required) - Todo ID to complete

Generated structure:

app.Register("list", &cli.Command{
    // ...
})

app.Register("add", &cli.Command{
    // ...
})

app.Register("complete", &cli.Command{
    // ...
})

Usage:

todo list
todo add --title "Buy groceries" --priority "high"
todo complete --id 1

Example 3: Server CLI with Configuration

Generate a CLI for managing a server:

cli init --name server --type single

Add flags:

• --port (Int, default: 8080, alias: -p)
• --host (String, default: "localhost")
• --config (String, env: SERVER_CONFIG)
• --verbose (Bool, alias: -v)

Generated code:

Flags: []cli.Flag{
    &cli.IntFlag{
        Name:    "port",
        Usage:   "Server port",
        Value:   8080,
        Aliases: []string{"p"},
    },
    &cli.StringFlag{
        Name:    "host",
        Usage:   "Server host",
        Value:   "localhost",
    },
    &cli.StringFlag{
        Name:    "config",
        Usage:   "Config file path",
        EnvVars: []string{"SERVER_CONFIG"},
    },
    &cli.BoolFlag{
        Name:    "verbose",
        Usage:   "Enable verbose logging",
        Aliases: []string{"v"},
    },
}

Usage:

server --port 3000 --host 0.0.0.0
server -p 3000 -v
SERVER_CONFIG=/path/to/config server

Example 4: File Operations CLI

Generate a CLI for file operations:

cli init --name fileops --type multiple

Add commands:

1. copy command

   • --source (String, required)
   • --destination (String, required)
   • --recursive (Bool)

2. move command

   • --source (String, required)
   • --destination (String, required)

3. delete command

   • --path (String, required)
   • --force (Bool)

Example 5: API Client CLI

Generate a CLI for interacting with an API:

cli init --name apiclient --type single

Add flags:

• --endpoint (String, required, env: API_ENDPOINT)
• --token (String, required, env: API_TOKEN)
• --method (String, default: "GET")
• --data (String) - JSON data
• --headers (StringSlice) - Additional headers

Usage:

apiclient --endpoint https://api.example.com/users --method GET
apiclient --endpoint https://api.example.com/users --method POST --data '{"name":"John"}'
API_ENDPOINT=https://api.example.com API_TOKEN=xxx apiclient --method GET

Best Practices

1. Use meaningful names: Choose descriptive project and command names
2. Add helpful descriptions: Write clear usage descriptions for flags and commands
3. Set defaults: Provide sensible default values for optional flags
4. Use aliases: Add short aliases for commonly used flags
5. Environment variables: Enable environment variable support for sensitive data
6. Organize commands: Group related commands logically in multiple commands mode