var value string
parser.Opt("--power-level", args.StoreString(&value))
cmdLine := []string{"--power-level", "over-ten-thousand"}
opt, err := parser.ParseArgs(&cmdLine)
Expect(err).To(BeNil())
Expect(opt.String("power-level")).To(Equal("over-ten-thousand"))
Expect(value).To(Equal("over-ten-thousand"))
})
})
Describe("args.StoreStr()", func() {
It("Should ensure value supplied is assigned to passed value", func() {
parser := args.Parser()
var value string
parser.Opt("--power-level", args.StoreStr(&value))
cmdLine := []string{"--power-level", "over-ten-thousand"}
opt, err := parser.ParseArgs(&cmdLine)
Expect(err).To(BeNil())
Expect(opt.String("power-level")).To(Equal("over-ten-thousand"))
Expect(value).To(Equal("over-ten-thousand"))
})
})
Describe("args.StoreTrue()", func() {
It("Should ensure value supplied is true when argument is seen", func() {
parser := args.Parser()
var debug bool
parser.Opt("--debug", args.StoreTrue(&debug))
func main() {
var conf Config
// Create the parser
parser := args.Parser(args.Name("example"))
// Store Integers directly into a struct with a default value
parser.Opt("--power-level", args.Alias("-p"), args.StoreInt(&conf.PowerLevel),
args.Env("POWER_LEVEL"), args.Default("10000"), args.Help("set our power level"))
// Options can begin with -name, --name or even ++name. Most alpha non word character are supported
parser.Opt("++power", args.Alias("+p"), args.IsString(), args.Default("11,000"),
args.Help("prefix demo"))
// Use the args.Env() function to define an environment variable
parser.Opt("--message", args.Alias("-m"), args.StoreStr(&conf.Message),
args.Env("MESSAGE"), args.Default("over-ten-thousand"), args.Help("send a message"))
// Pass a comma seperated list of strings and get a []string
parser.Opt("--slice", args.Alias("-s"), args.StoreSlice(&conf.Slice),
args.Env("LIST"), args.Default("one,two,three"), args.Help("list of messages"))
// Count the number of times an argument is seen
parser.Opt("--verbose", args.Alias("-v"), args.Count(), args.StoreInt(&conf.Verbose),
args.Help("be verbose"))
// Set bool to true if the argument is present on the command line
parser.Opt("--debug", args.Alias("-d"), args.IsTrue(), args.Help("turn on Debug"))
// Specify the type of the arg with IsInt(), IsString(), IsBool() or IsTrue()
parser.Opt("--help", args.Alias("-h"), args.IsTrue(), args.Help("show this help message"))
// Pass our own argument list, or nil to parse os.Args[]
opt, err := parser.ParseArgs(nil)
if err != nil {
fmt.Println(err.Error())
os.Exit(-1)
}
// Fetch values by using the Cast functions
fmt.Printf("CAST Power '%d'\n", opt.Int("power-level"))
fmt.Printf("CAST Message '%s'\n", opt.String("message"))
fmt.Printf("CAST Slice '%s'\n", opt.Slice("slice"))
fmt.Printf("CAST Verbose '%d'\n", opt.Int("verbose"))
fmt.Printf("CAST Debug '%t'\n", opt.Bool("debug"))
fmt.Println("")
// Values can also be stored in a struct
fmt.Printf("STRUCT Power '%d'\n", conf.PowerLevel)
fmt.Printf("STRUCT Message '%s'\n", conf.Message)
fmt.Printf("STRUCT Slice '%s'\n", conf.Slice)
fmt.Printf("STRUCT Verbose '%d'\n", conf.Verbose)
fmt.Printf("STRUCT Debug '%t'\n", opt.Bool("debug"))
fmt.Println("")
iniFile := []byte(`
power-level=20000
message=OVER-THEN-THOUSAND!
slice=three,four,five,six
verbose=5
debug=true
`)
// Make configuration simply by reading arguments from an INI file
opt, err = parser.ParseIni(iniFile)
if err != nil {
fmt.Println(err.Error())
os.Exit(-1)
}
// Values from the config file are used only if the argument is not present
// on the commandline
fmt.Printf("INI Power '%d'\n", conf.PowerLevel)
fmt.Printf("INI Message '%s'\n", conf.Message)
fmt.Printf("INI Slice '%s'\n", conf.Slice)
fmt.Printf("INI Verbose '%d'\n", conf.Verbose)
fmt.Printf("INI Debug '%t'\n", opt.Bool("debug"))
fmt.Println("")
// If user asked for --help or there were no options passed
if opt.NoArgs() || opt.Bool("help") {
parser.PrintHelp()
os.Exit(-1)
}
}