fix bug #545 (#555)

internal/push/offlinepush/offlinepush_interface.go

@@ -18,10 +18,12 @@ import (
 	"context"
 )
 
+// OfflinePusher Offline Pusher
 type OfflinePusher interface {
 	Push(ctx context.Context, userIDs []string, title, content string, opts *Opts) error
 }
 
+// Opts opts
 type Opts struct {
 	Signal        *Signal
 	IOSPushSound  string
@@ -29,6 +31,7 @@ type Opts struct {
 	Ex            string
 }
 
+// Signal message id
 type Signal struct {
 	ClientMsgID string
 }