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|
---
tags:
- v1
---
One of the philosophies behind cli is that an API should be playful and full of
discovery. So a cli app can be as little as one line of code in `main()`.
<!-- {
"args": ["--help"],
"output": "A new cli application"
} -->
``` go
package main
import (
"log"
"os"
"github.com/urfave/cli"
)
func main() {
err := cli.NewApp().Run(os.Args)
if err != nil {
log.Fatal(err)
}
}
```
This app will run and show help text, but is not very useful. Let's give an
action to execute and some help documentation:
<!-- {
"output": "boom! I say!"
} -->
``` go
package main
import (
"fmt"
"log"
"os"
"github.com/urfave/cli"
)
func main() {
app := cli.NewApp()
app.Name = "boom"
app.Usage = "make an explosive entrance"
app.Action = func(c *cli.Context) error {
fmt.Println("boom! I say!")
return nil
}
err := app.Run(os.Args)
if err != nil {
log.Fatal(err)
}
}
```
Running this already gives you a ton of functionality, plus support for things
like subcommands and flags, which are covered below.
|
