Package nutrition provides decoding of different sources based on user defined struct. Source is the stream of lines in 'key=value' form. Environment, file and raw io.Reader sources are supported. Package can decode types boolean, numeric, and string types as well as time.Duration and time.Time. The later could be customized with formats.
The Nutrition API reference is available on GoDoc.
Install Nutrition using the go get command:
go get -u github.com/dmotylev/nutrition
Feed struct from environment only:
// Try:
//
// APP_TIMEOUT=1h2m3s APP_DAY=2013-12-13 APP_NUMWORKERS=5 APP_WORKERNAME=Hulk go run p.go
//
package main
import (
"fmt"
"time"
"github.com/dmotylev/nutrition"
)
func main() {
var conf struct {
Timeout time.Duration
Day time.Time `time,format:"2006-01-02"`
WorkerName string
NumWorkers int
}
err := nutrition.Env("APP_").Feed(&conf)
fmt.Printf("err=%v\n", err)
fmt.Printf("timeout=%s\n", conf.Timeout)
fmt.Printf("day=%s\n", conf.Day.Format(time.UnixDate))
fmt.Printf("worker=%s\n", conf.WorkerName)
fmt.Printf("workers=%d\n", conf.NumWorkers)
}Feed struct from stdin only:
// Try:
//
// echo -e "timeout=1h2m3s\nday=2013-12-13\nnumWorkers=5\nworkerName=Hulk" | go run p.go
//
package main
import (
"fmt"
"time"
"os"
"github.com/dmotylev/nutrition"
)
func main() {
var conf struct {
Timeout time.Duration
Day time.Time `time,format:"2006-01-02"`
WorkerName string
NumWorkers int
}
err := nutrition.Reader(os.Stdin).Feed(&conf)
fmt.Printf("err=%v\n", err)
fmt.Printf("timeout=%s\n", conf.Timeout)
fmt.Printf("day=%s\n", conf.Day.Format(time.UnixDate))
fmt.Printf("worker=%s\n", conf.WorkerName)
fmt.Printf("workers=%d\n", conf.NumWorkers)
}Feed struct from file only:
// Try:
//
// echo -e "timeout=1h2m3s\nday=2013-12-13\nnumWorkers=5\nworkerName=Hulk" > env && go run p.go
//
package main
import (
"fmt"
"time"
"github.com/dmotylev/nutrition"
)
func main() {
var conf struct {
Timeout time.Duration
Day time.Time `time,format:"2006-01-02"`
WorkerName string
NumWorkers int
}
err := nutrition.Reader("env").Feed(&conf)
fmt.Printf("err=%v\n", err)
fmt.Printf("timeout=%s\n", conf.Timeout)
fmt.Printf("day=%s\n", conf.Day.Format(time.UnixDate))
fmt.Printf("worker=%s\n", conf.WorkerName)
fmt.Printf("workers=%d\n", conf.NumWorkers)
}All together:
// Try:
//
// echo -e "timeout=1h2m3s\nday=2013-12-13\nnumWorkers=5\nworkerName=Hulk" > env && echo -e "numWorkers=10000\nworkerName=Fido" | APP_WORKERNAME=Pinnoccio go run p.go
//
package main
import (
"fmt"
"os"
"time"
"github.com/dmotylev/nutrition"
)
func main() {
var conf struct {
Timeout time.Duration
Day time.Time `time,format:"2006-01-02"`
WorkerName string
NumWorkers int
}
// You can change the order. First source with value will be used
err := nutrition.Env("APP_").Reader(os.Stdin).File("env").Feed(&conf)
fmt.Printf("err=%v\n", err)
fmt.Printf("timeout=%s\n", conf.Timeout)
fmt.Printf("day=%s\n", conf.Day.Format(time.UnixDate))
fmt.Printf("worker=%s\n", conf.WorkerName)
fmt.Printf("workers=%d\n", conf.NumWorkers)
}The package available under LICENSE.