gistfile1.txt

package nats

import (
	"errors"
	"fmt"
	"reflect"
	"strings"
	"time"

	"github.com/nats-io/go-nats"
)

func NewNats(c *nats.EncodedConn) *Nats {
	return &Nats{
		c: c,
	}
}

type Nats struct {
	c *nats.EncodedConn
}

func (n *Nats) Publish(v interface{}) error {

	t := reflect.TypeOf(v)
	subject, err := toSubject(t)
	if err != nil {
		return err
	}

	return n.c.Publish(subject, v)
}

func (n *Nats) Reply(subject string, v interface{}) error {
	//log.Printf("Reply Called with %s", spew.Sdump(v))

	return n.c.Publish(subject, v)
}

func (n *Nats) Request(v interface{}, vPtr interface{}, timeout time.Duration) error {

	t := reflect.TypeOf(v)
	subject, err := toSubject(t)
	if err != nil {
		return err
	}

	return n.c.Request(subject, v, vPtr, timeout)
}

func (n *Nats) Subscribe(cb nats.Handler) (*nats.Subscription, error) {
	if cb == nil {
		return nil, errors.New("handler required for EncodedConn Subscription")
	}

	cbType := reflect.TypeOf(cb)
	if cbType.Kind() != reflect.Func {
		return nil, errors.New("handler needs to be a func")
	}
	numArgs := cbType.NumIn()
	if numArgs == 0 {
		return nil, errors.New("handled require at least one argument")
	}

	target := cbType.In(numArgs - 1)
	subject, err := toSubject(target)
	if err != nil {
		return nil, err
	}

	return n.c.Subscribe(subject, cb)
}

func (n *Nats) QueueSubscribe(queue string, cb nats.Handler) (*nats.Subscription, error) {
	if cb == nil {
		return nil, errors.New("handler required for EncodedConn Subscription")
	}

	cbType := reflect.TypeOf(cb)
	if cbType.Kind() != reflect.Func {
		return nil, errors.New("handler needs to be a func")
	}
	numArgs := cbType.NumIn()
	if numArgs == 0 {
		return nil, errors.New("handled require at least one argument")
	}

	target := cbType.In(numArgs - 1)
	subject, err := toSubject(target)
	if err != nil {
		return nil, err
	}

	return n.c.QueueSubscribe(subject, queue, cb)
}

func toSubject(t reflect.Type) (string, error) {
	target := fmt.Sprintf("Target :%+v", t)

	if strings.Contains(target, "Command") {
		return strings.Replace(fmt.Sprintf("command.%s", t), "*", "", -1), nil
	}

	if strings.Contains(target, "Event") {
		return strings.Replace(fmt.Sprintf("event.%s", t), "*", "", -1), nil
	}

	return strings.Replace(fmt.Sprintf("data.%s", t), "*", "", -1), nil
}