chore: support single queue and multiple worker (#589)

queue/simple/simple.go

@@ -0,0 +1,59 @@
+package simple
+
+import (
+	"errors"
+
+	"github.com/appleboy/gorush/config"
+	"github.com/appleboy/gorush/gorush"
+)
+
+// Worker for simple queue using channel
+type Worker struct {
+	cfg               config.ConfYaml
+	queueNotification chan gorush.PushNotification
+}
+
+// Run start the worker
+func (s *Worker) Run(_ chan struct{}) {
+	for notification := range s.queueNotification {
+		gorush.SendNotification(s.cfg, notification)
+	}
+}
+
+// Stop worker
+func (s *Worker) Stop() {
+	close(s.queueNotification)
+}
+
+// Capacity for channel
+func (s *Worker) Capacity() int {
+	return cap(s.queueNotification)
+}
+
+// Usage for count of channel usage
+func (s *Worker) Usage() int {
+	return len(s.queueNotification)
+}
+
+// Enqueue send notification to queue
+func (s *Worker) Enqueue(job interface{}) error {
+	select {
+	case s.queueNotification <- job.(gorush.PushNotification):
+		return nil
+	default:
+		return errors.New("max capacity reached")
+	}
+}
+
+// Config update current config
+func (s *Worker) Config(cfg config.ConfYaml) {
+	s.cfg = cfg
+}
+
+// NewWorker for struct
+func NewWorker(cfg config.ConfYaml) *Worker {
+	return &Worker{
+		cfg:               cfg,
+		queueNotification: make(chan gorush.PushNotification, cfg.Core.QueueNum),
+	}
+}