diff --git a/engine/tpreader_test.go b/engine/tpreader_test.go
new file mode 100644
index 000000000..995fa03a8
--- /dev/null
+++ b/engine/tpreader_test.go
@@ -0,0 +1,425 @@
+/*
+Real-time Online/Offline Charging System (OCS) for Telecom & ISP environments
+Copyright (C) ITsysCOM GmbH
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>
+*/
+
+package engine
+
+import (
+	"bytes"
+	"fmt"
+	"log"
+	"os"
+	"reflect"
+	"testing"
+
+	"github.com/cgrates/birpc"
+	"github.com/cgrates/birpc/context"
+	"github.com/cgrates/cgrates/config"
+	"github.com/cgrates/cgrates/utils"
+	"github.com/cgrates/rpcclient"
+)
+
+func TestCallCacheNoCaching(t *testing.T) {
+	tmp1, tmp2 := connMgr, Cache
+	defer func() {
+		connMgr = tmp1
+		Cache = tmp2
+	}()
+
+	defaultCfg := config.NewDefaultCGRConfig()
+	Cache = NewCacheS(defaultCfg, nil, nil)
+	cM := NewConnManager(defaultCfg, nil)
+	cacheConns := []string{}
+	caching := utils.MetaNone
+	args := map[string][]string{
+		utils.FilterIDs:   {"cgrates.org:FLTR_ID1", "cgrates.org:FLTR_ID2"},
+		utils.ResourceIDs: {},
+	}
+	cacheIDs := []string{}
+	opts := map[string]interface{}{
+		utils.Subsys: utils.MetaChargers,
+	}
+	ctx := context.Background()
+
+	expArgs := map[string][]string{
+		utils.FilterIDs: {"cgrates.org:FLTR_ID1", "cgrates.org:FLTR_ID2"},
+	}
+	err := CallCache(cM, ctx, cacheConns, caching, args, cacheIDs, opts, true)
+
+	if err != nil {
+		t.Errorf("\nexpected: <%+v>, \nreceived: <%+v>", nil, err)
+	}
+
+	if !reflect.DeepEqual(args, expArgs) {
+		t.Errorf("\nexpected: <%+v>, \nreceived: <%+v>", expArgs, args)
+	}
+}
+
+func TestCallCacheReloadCacheFirstCallFail(t *testing.T) {
+	tmp1, tmp2 := connMgr, Cache
+	defer func() {
+		connMgr = tmp1
+		Cache = tmp2
+	}()
+
+	defaultCfg := config.NewDefaultCGRConfig()
+	Cache = NewCacheS(defaultCfg, nil, nil)
+	cacheConns := []string{"cacheConn1"}
+	client := make(chan birpc.ClientConnector, 1)
+	mCC := &mockClientConnector{
+		calls: map[string]func(_ *context.Context, args interface{}, reply interface{}) error{
+			utils.CacheSv1ReloadCache: func(_ *context.Context, args, reply interface{}) error {
+				expArgs := utils.AttrReloadCacheWithAPIOpts{
+					APIOpts: map[string]interface{}{
+						utils.Subsys: utils.MetaChargers,
+					},
+					ArgsCache: map[string][]string{
+						utils.FilterIDs: {"cgrates.org:FLTR_ID1", "cgrates.org:FLTR_ID2"},
+					},
+				}
+
+				if !reflect.DeepEqual(args, expArgs) {
+					return fmt.Errorf(
+						"\nWrong value of args: \nexpected: <%+v>, \nreceived: <%+v>",
+						expArgs, args,
+					)
+				}
+				return utils.ErrUnsupporteServiceMethod
+			},
+		},
+	}
+	client <- mCC
+
+	cM := NewConnManager(defaultCfg, map[string]chan birpc.ClientConnector{
+		"cacheConn1": client,
+	})
+	caching := utils.MetaReload
+	args := map[string][]string{
+		utils.FilterIDs: {"cgrates.org:FLTR_ID1", "cgrates.org:FLTR_ID2"},
+	}
+	cacheIDs := []string{}
+	opts := map[string]interface{}{
+		utils.Subsys: utils.MetaChargers,
+	}
+	ctx := context.Background()
+
+	var buf bytes.Buffer
+	log.SetOutput(&buf)
+	defer func() {
+		log.SetOutput(os.Stderr)
+	}()
+
+	explog := "Reloading cache\n"
+	experr := utils.ErrUnsupporteServiceMethod
+	err := CallCache(cM, ctx, cacheConns, caching, args, cacheIDs, opts, true)
+
+	if err == nil || err != experr {
+		t.Errorf("\nexpected: <%+v>, \nreceived: <%+v>", experr, err)
+	}
+
+	rcvlog := buf.String()[20:]
+	if rcvlog != explog {
+		t.Errorf("\nexpected: <%+v>, \nreceived: <%+v>", explog, rcvlog)
+	}
+}
+
+func TestCallCacheReloadCacheSecondCallFailed(t *testing.T) {
+	tmp1, tmp2 := connMgr, Cache
+	defer func() {
+		connMgr = tmp1
+		Cache = tmp2
+	}()
+
+	defaultCfg := config.NewDefaultCGRConfig()
+	Cache = NewCacheS(defaultCfg, nil, nil)
+	cacheConns := []string{"cacheConn1"}
+	client := make(chan birpc.ClientConnector, 1)
+	mCC := &mockClientConnector{
+		calls: map[string]func(_ *context.Context, args interface{}, reply interface{}) error{
+			utils.CacheSv1ReloadCache: func(_ *context.Context, args, reply interface{}) error {
+				return nil
+			},
+			utils.CacheSv1Clear: func(_ *context.Context, args, reply interface{}) error {
+				expArgs := &utils.AttrCacheIDsWithAPIOpts{
+					APIOpts: map[string]interface{}{
+						utils.Subsys: utils.MetaChargers,
+					},
+					CacheIDs: []string{"cacheID"},
+				}
+
+				if !reflect.DeepEqual(args, expArgs) {
+					return fmt.Errorf(
+						"\nWrong value of args: \nexpected: <%+v>, \nreceived: <%+v>",
+						expArgs, args,
+					)
+				}
+				return utils.ErrUnsupporteServiceMethod
+			},
+		},
+	}
+	client <- mCC
+
+	cM := NewConnManager(defaultCfg, map[string]chan birpc.ClientConnector{
+		"cacheConn1": client,
+	})
+	caching := utils.MetaReload
+	args := map[string][]string{
+		utils.FilterIDs: {"cgrates.org:FLTR_ID1", "cgrates.org:FLTR_ID2"},
+	}
+	cacheIDs := []string{"cacheID"}
+	opts := map[string]interface{}{
+		utils.Subsys: utils.MetaChargers,
+	}
+	ctx := context.Background()
+
+	var buf bytes.Buffer
+	log.SetOutput(&buf)
+	defer func() {
+		log.SetOutput(os.Stderr)
+	}()
+
+	explog1 := "Reloading cache"
+	explog2 := "Clearing indexes"
+	experr := utils.ErrUnsupporteServiceMethod
+	explog3 := fmt.Sprintf("WARNING: Got error on cache clear: %s\n", experr)
+	err := CallCache(cM, ctx, cacheConns, caching, args, cacheIDs, opts, true)
+
+	if err == nil || err != experr {
+		t.Errorf("\nexpected: <%+v>, \nreceived: <%+v>", experr, err)
+	}
+
+	rcvlog1 := buf.String()[20 : 20+len(explog1)]
+	if rcvlog1 != explog1 {
+		t.Errorf("\nexpected: <%+v>, \nreceived: <%+v>", explog1, rcvlog1)
+	}
+
+	rcvlog2 := buf.String()[41+len(rcvlog1) : 41+len(rcvlog1)+len(explog2)]
+	if rcvlog2 != explog2 {
+		t.Errorf("\nexpected: <%+v>, \nreceived: <%+v>", explog2, rcvlog2)
+	}
+
+	rcvlog3 := buf.String()[62+len(rcvlog1)+len(explog2):]
+	if rcvlog3 != explog3 {
+		t.Errorf("\nexpected: <%+v>, \nreceived: <%+v>", explog3, rcvlog3)
+	}
+}
+
+func TestCallCacheLoadCache(t *testing.T) {
+	tmp1, tmp2 := connMgr, Cache
+	defer func() {
+		connMgr = tmp1
+		Cache = tmp2
+	}()
+
+	defaultCfg := config.NewDefaultCGRConfig()
+	Cache = NewCacheS(defaultCfg, nil, nil)
+	cacheConns := []string{"cacheConn1"}
+	client := make(chan birpc.ClientConnector, 1)
+	mCC := &mockClientConnector{
+		calls: map[string]func(_ *context.Context, args interface{}, reply interface{}) error{
+			utils.CacheSv1LoadCache: func(_ *context.Context, args, reply interface{}) error {
+				expArgs := utils.AttrReloadCacheWithAPIOpts{
+					APIOpts: map[string]interface{}{
+						utils.Subsys: utils.MetaChargers,
+					},
+					ArgsCache: map[string][]string{
+						utils.FilterIDs: {"cgrates.org:FLTR_ID1", "cgrates.org:FLTR_ID2"},
+					},
+				}
+
+				if !reflect.DeepEqual(args, expArgs) {
+					return fmt.Errorf(
+						"\nWrong value of args: \nexpected: <%+v>, \nreceived: <%+v>",
+						expArgs, args,
+					)
+				}
+				return nil
+			},
+			utils.CacheSv1Clear: func(_ *context.Context, args, reply interface{}) error {
+				expArgs := &utils.AttrCacheIDsWithAPIOpts{
+					APIOpts: map[string]interface{}{
+						utils.Subsys: utils.MetaChargers,
+					},
+					CacheIDs: []string{"cacheID"},
+				}
+
+				if !reflect.DeepEqual(args, expArgs) {
+					return fmt.Errorf(
+						"\nWrong value of args: \nexpected: <%+v>, \nreceived: <%+v>",
+						expArgs, args,
+					)
+				}
+				return nil
+			},
+		},
+	}
+	client <- mCC
+
+	cM := NewConnManager(defaultCfg, map[string]chan birpc.ClientConnector{
+		"cacheConn1": client,
+	})
+	caching := utils.MetaLoad
+	args := map[string][]string{
+		utils.FilterIDs: {"cgrates.org:FLTR_ID1", "cgrates.org:FLTR_ID2"},
+	}
+	cacheIDs := []string{"cacheID"}
+	opts := map[string]interface{}{
+		utils.Subsys: utils.MetaChargers,
+	}
+	ctx := context.Background()
+
+	err := CallCache(cM, ctx, cacheConns, caching, args, cacheIDs, opts, false)
+
+	if err != nil {
+		t.Errorf("\nexpected: <%+v>, \nreceived: <%+v>", nil, err)
+	}
+}
+
+func TestCallCacheRemoveItems(t *testing.T) {
+	tmp1, tmp2 := connMgr, Cache
+	defer func() {
+		connMgr = tmp1
+		Cache = tmp2
+	}()
+
+	defaultCfg := config.NewDefaultCGRConfig()
+	Cache = NewCacheS(defaultCfg, nil, nil)
+	cacheConns := []string{"cacheConn1"}
+	client := make(chan birpc.ClientConnector, 1)
+	mCC := &mockClientConnector{
+		calls: map[string]func(_ *context.Context, args interface{}, reply interface{}) error{
+			utils.CacheSv1RemoveItems: func(_ *context.Context, args, reply interface{}) error {
+				expArgs := utils.AttrReloadCacheWithAPIOpts{
+					APIOpts: map[string]interface{}{
+						utils.Subsys: utils.MetaChargers,
+					},
+					ArgsCache: map[string][]string{
+						utils.FilterIDs: {"cgrates.org:FLTR_ID1", "cgrates.org:FLTR_ID2"},
+					},
+				}
+
+				if !reflect.DeepEqual(args, expArgs) {
+					return fmt.Errorf(
+						"\nWrong value of args: \nexpected: <%+v>, \nreceived: <%+v>",
+						expArgs, args,
+					)
+				}
+				return nil
+			},
+			utils.CacheSv1Clear: func(_ *context.Context, args, reply interface{}) error {
+				expArgs := &utils.AttrCacheIDsWithAPIOpts{
+					APIOpts: map[string]interface{}{
+						utils.Subsys: utils.MetaChargers,
+					},
+					CacheIDs: []string{"cacheID"},
+				}
+
+				if !reflect.DeepEqual(args, expArgs) {
+					return fmt.Errorf(
+						"\nWrong value of args: \nexpected: <%+v>, \nreceived: <%+v>",
+						expArgs, args,
+					)
+				}
+				return nil
+			},
+		},
+	}
+	client <- mCC
+
+	cM := NewConnManager(defaultCfg, map[string]chan birpc.ClientConnector{
+		"cacheConn1": client,
+	})
+	caching := utils.MetaRemove
+	args := map[string][]string{
+		utils.FilterIDs: {"cgrates.org:FLTR_ID1", "cgrates.org:FLTR_ID2"},
+	}
+	cacheIDs := []string{"cacheID"}
+	opts := map[string]interface{}{
+		utils.Subsys: utils.MetaChargers,
+	}
+	ctx := context.Background()
+
+	err := CallCache(cM, ctx, cacheConns, caching, args, cacheIDs, opts, false)
+
+	if err != nil {
+		t.Errorf("\nexpected: <%+v>, \nreceived: <%+v>", nil, err)
+	}
+}
+
+func TestCallCacheClear(t *testing.T) {
+	tmp1, tmp2 := connMgr, Cache
+	defer func() {
+		connMgr = tmp1
+		Cache = tmp2
+	}()
+
+	defaultCfg := config.NewDefaultCGRConfig()
+	Cache = NewCacheS(defaultCfg, nil, nil)
+	cacheConns := []string{"cacheConn1"}
+	client := make(chan birpc.ClientConnector, 1)
+	mCC := &mockClientConnector{
+		calls: map[string]func(_ *context.Context, args interface{}, reply interface{}) error{
+			utils.CacheSv1Clear: func(_ *context.Context, args, reply interface{}) error {
+				expArgs := &utils.AttrCacheIDsWithAPIOpts{
+					APIOpts: map[string]interface{}{
+						utils.Subsys: utils.MetaChargers,
+					},
+				}
+
+				if !reflect.DeepEqual(args, expArgs) {
+					return fmt.Errorf(
+						"\nWrong value of args: \nexpected: <%+v>, \nreceived: <%+v>",
+						expArgs, args,
+					)
+				}
+				return nil
+			},
+		},
+	}
+	client <- mCC
+
+	cM := NewConnManager(defaultCfg, map[string]chan birpc.ClientConnector{
+		"cacheConn1": client,
+	})
+	caching := utils.MetaClear
+	args := map[string][]string{
+		utils.FilterIDs: {"cgrates.org:FLTR_ID1", "cgrates.org:FLTR_ID2"},
+	}
+	cacheIDs := []string{}
+	opts := map[string]interface{}{
+		utils.Subsys: utils.MetaChargers,
+	}
+	ctx := context.Background()
+
+	err := CallCache(cM, ctx, cacheConns, caching, args, cacheIDs, opts, false)
+
+	if err != nil {
+		t.Errorf("\nexpected: <%+v>, \nreceived: <%+v>", nil, err)
+	}
+}
+
+type mockClientConnector struct {
+	calls map[string]func(_ *context.Context, _, _ interface{}) error
+}
+
+func (mCC *mockClientConnector) Call(ctx *context.Context, method string, args, rply interface{}) error {
+	if call, has := mCC.calls[method]; !has {
+		return rpcclient.ErrUnsupporteServiceMethod
+	} else {
+		return call(ctx, args, rply)
+	}
+}