gocmd
A Go library for building command line applications.
Features
- Advanced command line arguments handling
- Subcommand handling
- Short and long command line arguments
- Multiple arguments (repeated or delimited)
- Support for environment variables
- Well formatted usage printing
- Auto usage and version printing
- Unknown argument handling
- Output tables in the terminal
- Template support for config files
- No external dependency
Installation
go get github.com/devfacet/gocmd/v3Usage
A basic app
For the full code click here.
func main() {
flags := struct {
Help bool `short:"h" long:"help" description:"Display usage" global:"true"`
Version bool `short:"v" long:"version" description:"Display version"`
VersionEx bool `long:"vv" description:"Display version (extended)"`
Echo struct {
Settings bool `settings:"true" allow-unknown-arg:"true"`
} `command:"echo" description:"Print arguments"`
Math struct {
Sqrt struct {
Number float64 `short:"n" long:"number" required:"true" description:"Number"`
} `command:"sqrt" description:"Calculate square root"`
Pow struct {
Base float64 `short:"b" long:"base" required:"true" description:"Base"`
Exponent float64 `short:"e" long:"exponent" required:"true" description:"Exponent"`
} `command:"pow" description:"Calculate base exponential"`
} `command:"math" description:"Math functions" nonempty:"true"`
}{}
// Echo command
gocmd.HandleFlag("Echo", func(cmd *gocmd.Cmd, args []string) error {
fmt.Printf("%s\n", strings.Join(cmd.FlagArgs("Echo")[1:], " "))
return nil
})
// Math commands
gocmd.HandleFlag("Math.Sqrt", func(cmd *gocmd.Cmd, args []string) error {
fmt.Println(math.Sqrt(flags.Math.Sqrt.Number))
return nil
})
gocmd.HandleFlag("Math.Pow", func(cmd *gocmd.Cmd, args []string) error {
fmt.Println(math.Pow(flags.Math.Pow.Base, flags.Math.Pow.Exponent))
return nil
})
// Init the app
gocmd.New(gocmd.Options{
Name: "basic",
Description: "A basic app",
Version: fmt.Sprintf("%s (%s)", version, gitCommit),
Flags: &flags,
ConfigType: gocmd.ConfigTypeAuto,
})
}# Build the example app:
make build
# Run it:
gocmdbasicUsage: basic [options...] COMMAND [options...]
A basic app
Options:
-h, --help Display usage
-v, --version Display version
--vv Display version (extended)
Commands:
echo Print arguments
math Math functions
sqrt Calculate square root
-n, --number Number
pow Calculate base exponential
-b, --base Base
-e, --exponent Exponent# Try the following commands:
gocmdbasic echo hello world
gocmdbasic math sqrt -n 9
gocmdbasic math pow -b 2 --exponent 2
gocmdbasic -v
gocmdbasic --vvTest
# Test everything:
make test
# For BDD development:
# It will open a new browser window. Make sure:
# 1. There is no errors on the terminal window.
# 2. There is no other open GoConvey page.
make test-ui
# Benchmarks
make test-benchmarksRelease
# Update and commit CHANGELOG.md first (i.e. git add CHANGELOG.md && git commit -m "v1.0.0").
# Set GIT_TAG using semver (i.e. GIT_TAG=v1.0.0)
make release GIT_TAG=Contributing
See CONTRIBUTING.md
License
Licensed under The MIT License (MIT)
For the full copyright and license information, please view the LICENSE.txt file.