fix zero time check

backend/_example/memory_store/accessor/data.go

@@ -89,7 +89,7 @@ func (m *MemData) Find(req engine.FindRequest) (comments []store.Comment, err er
 
 	case req.Locator.SiteID != "" && req.Locator.URL != "": // find comments for site and url
 		comments = m.match(m.posts[req.Locator.SiteID], func(c store.Comment) bool {
-			return c.Locator == req.Locator && c.Timestamp.After(req.Since)
+			return c.Locator == req.Locator && (req.Since.IsZero() || c.Timestamp.After(req.Since))
 		})
 
 	case req.Locator.SiteID != "" && req.Locator.URL == "" && req.UserID == "": // find last comments for site

backend/_example/memory_store/main.go

@@ -10,11 +10,10 @@ import (
 	"fmt"
 	"os"
 
+	"github.com/go-pkgz/jrpc"
 	log "github.com/go-pkgz/lgr"
 	"github.com/jessevdk/go-flags"
 
-	"github.com/umputun/remark/backend/app/rpc"
-
 	"github.com/umputun/remark/backend/_example/memory_store/accessor"
 	"github.com/umputun/remark/backend/_example/memory_store/server"
 )
@@ -43,7 +42,7 @@ func main() {
 	dataStore := accessor.NewMemData()
 	adminStore := accessor.NewMemAdminStore(opts.Secret)
 
-	rpcServer := rpc.Server{
+	rpcServer := jrpc.Server{
 		API:        opts.API,
 		AuthUser:   opts.AuthUser,
 		AuthPasswd: opts.AuthPasswd,