constellation/cli/internal/cmd/init_test.go
Daniel Weiße d1ace13713
cli: add --workspace flag to set base directory for Constellation workspace (#2148)
* Remove `--config` and `--master-secret` falgs

* Add `--workspace` flag

* In CLI, only work on files with paths created from `cli/internal/cmd`

* Properly print values for GCP on IAM create when not directly updating the config

---------

Signed-off-by: Daniel Weiße <dw@edgeless.systems>
2023-08-04 13:53:51 +02:00

666 lines
22 KiB
Go

/*
Copyright (c) Edgeless Systems GmbH
SPDX-License-Identifier: AGPL-3.0-only
*/
package cmd
import (
"bytes"
"context"
"encoding/hex"
"encoding/json"
"errors"
"io"
"net"
"strconv"
"strings"
"testing"
"time"
"github.com/edgelesssys/constellation/v2/bootstrapper/initproto"
"github.com/edgelesssys/constellation/v2/cli/internal/clusterid"
"github.com/edgelesssys/constellation/v2/cli/internal/helm"
"github.com/edgelesssys/constellation/v2/cli/internal/terraform"
"github.com/edgelesssys/constellation/v2/internal/atls"
"github.com/edgelesssys/constellation/v2/internal/attestation/measurements"
"github.com/edgelesssys/constellation/v2/internal/attestation/variant"
"github.com/edgelesssys/constellation/v2/internal/cloud/cloudprovider"
"github.com/edgelesssys/constellation/v2/internal/cloud/gcpshared"
"github.com/edgelesssys/constellation/v2/internal/config"
"github.com/edgelesssys/constellation/v2/internal/constants"
"github.com/edgelesssys/constellation/v2/internal/file"
"github.com/edgelesssys/constellation/v2/internal/grpc/atlscredentials"
"github.com/edgelesssys/constellation/v2/internal/grpc/dialer"
"github.com/edgelesssys/constellation/v2/internal/grpc/testdialer"
"github.com/edgelesssys/constellation/v2/internal/kms/uri"
"github.com/edgelesssys/constellation/v2/internal/license"
"github.com/edgelesssys/constellation/v2/internal/logger"
"github.com/edgelesssys/constellation/v2/internal/versions"
"github.com/spf13/afero"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
"google.golang.org/grpc"
)
func TestInitArgumentValidation(t *testing.T) {
assert := assert.New(t)
cmd := NewInitCmd()
assert.NoError(cmd.ValidateArgs(nil))
assert.Error(cmd.ValidateArgs([]string{"something"}))
assert.Error(cmd.ValidateArgs([]string{"sth", "sth"}))
}
func TestInitialize(t *testing.T) {
gcpServiceAccKey := &gcpshared.ServiceAccountKey{
Type: "service_account",
ProjectID: "project_id",
PrivateKeyID: "key_id",
PrivateKey: "key",
ClientEmail: "client_email",
ClientID: "client_id",
AuthURI: "auth_uri",
TokenURI: "token_uri",
AuthProviderX509CertURL: "cert",
ClientX509CertURL: "client_cert",
}
testInitResp := &initproto.InitSuccessResponse{
Kubeconfig: []byte("kubeconfig"),
OwnerId: []byte("ownerID"),
ClusterId: []byte("clusterID"),
}
serviceAccPath := "/test/service-account.json"
someErr := errors.New("failed")
testCases := map[string]struct {
provider cloudprovider.Provider
idFile *clusterid.File
configMutator func(*config.Config)
serviceAccKey *gcpshared.ServiceAccountKey
initServerAPI *stubInitServer
retriable bool
masterSecretShouldExist bool
wantErr bool
}{
"initialize some gcp instances": {
provider: cloudprovider.GCP,
idFile: &clusterid.File{IP: "192.0.2.1"},
configMutator: func(c *config.Config) { c.Provider.GCP.ServiceAccountKeyPath = serviceAccPath },
serviceAccKey: gcpServiceAccKey,
initServerAPI: &stubInitServer{res: &initproto.InitResponse{Kind: &initproto.InitResponse_InitSuccess{InitSuccess: testInitResp}}},
},
"initialize some azure instances": {
provider: cloudprovider.Azure,
idFile: &clusterid.File{IP: "192.0.2.1"},
initServerAPI: &stubInitServer{res: &initproto.InitResponse{Kind: &initproto.InitResponse_InitSuccess{InitSuccess: testInitResp}}},
},
"initialize some qemu instances": {
provider: cloudprovider.QEMU,
idFile: &clusterid.File{IP: "192.0.2.1"},
initServerAPI: &stubInitServer{res: &initproto.InitResponse{Kind: &initproto.InitResponse_InitSuccess{InitSuccess: testInitResp}}},
},
"non retriable error": {
provider: cloudprovider.QEMU,
idFile: &clusterid.File{IP: "192.0.2.1"},
initServerAPI: &stubInitServer{initErr: &nonRetriableError{someErr}},
retriable: false,
masterSecretShouldExist: true,
wantErr: true,
},
"empty id file": {
provider: cloudprovider.GCP,
idFile: &clusterid.File{},
initServerAPI: &stubInitServer{},
retriable: true,
wantErr: true,
},
"no id file": {
provider: cloudprovider.GCP,
retriable: true,
wantErr: true,
},
"init call fails": {
provider: cloudprovider.GCP,
idFile: &clusterid.File{IP: "192.0.2.1"},
initServerAPI: &stubInitServer{initErr: someErr},
retriable: true,
wantErr: true,
},
"k8s version without v works": {
provider: cloudprovider.Azure,
idFile: &clusterid.File{IP: "192.0.2.1"},
initServerAPI: &stubInitServer{res: &initproto.InitResponse{Kind: &initproto.InitResponse_InitSuccess{InitSuccess: testInitResp}}},
configMutator: func(c *config.Config) { c.KubernetesVersion = strings.TrimPrefix(string(versions.Default), "v") },
},
}
for name, tc := range testCases {
t.Run(name, func(t *testing.T) {
assert := assert.New(t)
require := require.New(t)
// Networking
netDialer := testdialer.NewBufconnDialer()
newDialer := func(atls.Validator) *dialer.Dialer {
return dialer.New(nil, nil, netDialer)
}
serverCreds := atlscredentials.New(nil, nil)
initServer := grpc.NewServer(grpc.Creds(serverCreds))
initproto.RegisterAPIServer(initServer, tc.initServerAPI)
port := strconv.Itoa(constants.BootstrapperPort)
listener := netDialer.GetListener(net.JoinHostPort("192.0.2.1", port))
go initServer.Serve(listener)
defer initServer.GracefulStop()
// Command
cmd := NewInitCmd()
var out bytes.Buffer
cmd.SetOut(&out)
var errOut bytes.Buffer
cmd.SetErr(&errOut)
// Flags
cmd.Flags().String("workspace", "", "") // register persistent flag manually
cmd.Flags().Bool("force", true, "") // register persistent flag manually
// File system preparation
fs := afero.NewMemMapFs()
fileHandler := file.NewHandler(fs)
config := defaultConfigWithExpectedMeasurements(t, config.Default(), tc.provider)
if tc.configMutator != nil {
tc.configMutator(config)
}
require.NoError(fileHandler.WriteYAML(constants.ConfigFilename, config, file.OptNone))
if tc.idFile != nil {
tc.idFile.CloudProvider = tc.provider
require.NoError(fileHandler.WriteJSON(constants.ClusterIDsFilename, tc.idFile, file.OptNone))
}
if tc.serviceAccKey != nil {
require.NoError(fileHandler.WriteJSON(serviceAccPath, tc.serviceAccKey, file.OptNone))
}
ctx := context.Background()
ctx, cancel := context.WithTimeout(ctx, 4*time.Second)
defer cancel()
cmd.SetContext(ctx)
i := newInitCmd(&stubShowCluster{}, &stubHelmInstaller{}, fileHandler, &nopSpinner{}, nil, logger.NewTest(t))
err := i.initialize(cmd, newDialer, &stubLicenseClient{}, stubAttestationFetcher{})
if tc.wantErr {
assert.Error(err)
if !tc.retriable {
assert.Contains(errOut.String(), "This error is not recoverable")
} else {
assert.Empty(errOut.String())
}
if !tc.masterSecretShouldExist {
_, err = fileHandler.Stat(constants.MasterSecretFilename)
assert.Error(err)
}
return
}
require.NoError(err)
// assert.Contains(out.String(), base64.StdEncoding.EncodeToString([]byte("ownerID")))
assert.Contains(out.String(), hex.EncodeToString([]byte("clusterID")))
var secret uri.MasterSecret
assert.NoError(fileHandler.ReadJSON(constants.MasterSecretFilename, &secret))
assert.NotEmpty(secret.Key)
assert.NotEmpty(secret.Salt)
})
}
}
func TestGetLogs(t *testing.T) {
someErr := errors.New("failed")
testCases := map[string]struct {
resp initproto.API_InitClient
fh file.Handler
wantedOutput []byte
wantErr bool
}{
"success": {
resp: stubInitClient{res: bytes.NewReader([]byte("asdf"))},
fh: file.NewHandler(afero.NewMemMapFs()),
wantedOutput: []byte("asdf"),
},
"receive error": {
resp: stubInitClient{err: someErr},
fh: file.NewHandler(afero.NewMemMapFs()),
wantErr: true,
},
"nil log": {
resp: stubInitClient{res: bytes.NewReader([]byte{1}), setResNil: true},
fh: file.NewHandler(afero.NewMemMapFs()),
wantErr: true,
},
"failed write": {
resp: stubInitClient{res: bytes.NewReader([]byte("asdf"))},
fh: file.NewHandler(afero.NewReadOnlyFs(afero.NewMemMapFs())),
wantErr: true,
},
}
for name, tc := range testCases {
t.Run(name, func(t *testing.T) {
assert := assert.New(t)
doer := initDoer{
fh: tc.fh,
log: logger.NewTest(t),
}
err := doer.getLogs(tc.resp)
if tc.wantErr {
assert.Error(err)
}
text, err := tc.fh.Read(constants.ErrorLog)
if tc.wantedOutput == nil {
assert.Error(err)
}
assert.Equal(tc.wantedOutput, text)
})
}
}
func TestWriteOutput(t *testing.T) {
assert := assert.New(t)
require := require.New(t)
resp := &initproto.InitResponse{
Kind: &initproto.InitResponse_InitSuccess{
InitSuccess: &initproto.InitSuccessResponse{
OwnerId: []byte("ownerID"),
ClusterId: []byte("clusterID"),
Kubeconfig: []byte("kubeconfig"),
},
},
}
ownerID := hex.EncodeToString(resp.GetInitSuccess().GetOwnerId())
clusterID := hex.EncodeToString(resp.GetInitSuccess().GetClusterId())
expectedIDFile := clusterid.File{
ClusterID: clusterID,
OwnerID: ownerID,
IP: "cluster-ip",
UID: "test-uid",
}
var out bytes.Buffer
testFs := afero.NewMemMapFs()
fileHandler := file.NewHandler(testFs)
idFile := clusterid.File{
UID: "test-uid",
IP: "cluster-ip",
}
i := newInitCmd(nil, nil, fileHandler, nil, &stubMerger{}, logger.NewTest(t))
err := i.writeOutput(idFile, resp.GetInitSuccess(), false, &out, "")
require.NoError(err)
// assert.Contains(out.String(), ownerID)
assert.Contains(out.String(), clusterID)
assert.Contains(out.String(), constants.AdminConfFilename)
afs := afero.Afero{Fs: testFs}
adminConf, err := afs.ReadFile(constants.AdminConfFilename)
assert.NoError(err)
assert.Equal(string(resp.GetInitSuccess().GetKubeconfig()), string(adminConf))
idsFile, err := afs.ReadFile(constants.ClusterIDsFilename)
assert.NoError(err)
var testIDFile clusterid.File
err = json.Unmarshal(idsFile, &testIDFile)
assert.NoError(err)
assert.Equal(expectedIDFile, testIDFile)
out.Reset()
require.NoError(afs.Remove(constants.AdminConfFilename))
// test custom workspace
err = i.writeOutput(idFile, resp.GetInitSuccess(), true, &out, "some/path")
require.NoError(err)
// assert.Contains(out.String(), ownerID)
assert.Contains(out.String(), clusterID)
assert.Contains(out.String(), adminConfPath("some/path"))
out.Reset()
// File is written to current working dir, we simply pass the workspace for generating readable user output
require.NoError(afs.Remove(constants.AdminConfFilename))
// test config merging
err = i.writeOutput(idFile, resp.GetInitSuccess(), true, &out, "")
require.NoError(err)
// assert.Contains(out.String(), ownerID)
assert.Contains(out.String(), clusterID)
assert.Contains(out.String(), constants.AdminConfFilename)
assert.Contains(out.String(), "Constellation kubeconfig merged with default config")
assert.Contains(out.String(), "You can now connect to your cluster")
out.Reset()
require.NoError(afs.Remove(constants.AdminConfFilename))
// test config merging with env vars set
i.merger = &stubMerger{envVar: "/some/path/to/kubeconfig"}
err = i.writeOutput(idFile, resp.GetInitSuccess(), true, &out, "")
require.NoError(err)
// assert.Contains(out.String(), ownerID)
assert.Contains(out.String(), clusterID)
assert.Contains(out.String(), constants.AdminConfFilename)
assert.Contains(out.String(), "Constellation kubeconfig merged with default config")
assert.Contains(out.String(), "Warning: KUBECONFIG environment variable is set")
}
func TestGenerateMasterSecret(t *testing.T) {
testCases := map[string]struct {
createFileFunc func(handler file.Handler) error
fs func() afero.Fs
wantErr bool
}{
"file already exists": {
fs: afero.NewMemMapFs,
createFileFunc: func(handler file.Handler) error {
return handler.WriteJSON(
constants.MasterSecretFilename,
uri.MasterSecret{Key: []byte("constellation-master-secret"), Salt: []byte("constellation-32Byte-length-salt")},
file.OptNone,
)
},
wantErr: true,
},
"file does not exist": {
createFileFunc: func(handler file.Handler) error { return nil },
fs: afero.NewMemMapFs,
wantErr: false,
},
"file not writeable": {
createFileFunc: func(handler file.Handler) error { return nil },
fs: func() afero.Fs { return afero.NewReadOnlyFs(afero.NewMemMapFs()) },
wantErr: true,
},
}
for name, tc := range testCases {
t.Run(name, func(t *testing.T) {
assert := assert.New(t)
require := require.New(t)
fileHandler := file.NewHandler(tc.fs())
require.NoError(tc.createFileFunc(fileHandler))
var out bytes.Buffer
i := newInitCmd(nil, nil, fileHandler, nil, nil, logger.NewTest(t))
secret, err := i.generateMasterSecret(&out, "")
if tc.wantErr {
assert.Error(err)
} else {
assert.NoError(err)
require.Contains(out.String(), constants.MasterSecretFilename)
var masterSecret uri.MasterSecret
require.NoError(fileHandler.ReadJSON(constants.MasterSecretFilename, &masterSecret))
assert.Equal(masterSecret.Key, secret.Key)
assert.Equal(masterSecret.Salt, secret.Salt)
}
})
}
}
func TestAttestation(t *testing.T) {
assert := assert.New(t)
require := require.New(t)
initServerAPI := &stubInitServer{res: &initproto.InitResponse{
Kind: &initproto.InitResponse_InitSuccess{
InitSuccess: &initproto.InitSuccessResponse{
Kubeconfig: []byte("kubeconfig"),
OwnerId: []byte("ownerID"),
ClusterId: []byte("clusterID"),
},
},
}}
existingIDFile := &clusterid.File{IP: "192.0.2.4", CloudProvider: cloudprovider.QEMU}
netDialer := testdialer.NewBufconnDialer()
issuer := &testIssuer{
Getter: variant.QEMUVTPM{},
pcrs: map[uint32][]byte{
0: bytes.Repeat([]byte{0xFF}, 32),
1: bytes.Repeat([]byte{0xFF}, 32),
2: bytes.Repeat([]byte{0xFF}, 32),
3: bytes.Repeat([]byte{0xFF}, 32),
},
}
serverCreds := atlscredentials.New(issuer, nil)
initServer := grpc.NewServer(grpc.Creds(serverCreds))
initproto.RegisterAPIServer(initServer, initServerAPI)
port := strconv.Itoa(constants.BootstrapperPort)
listener := netDialer.GetListener(net.JoinHostPort("192.0.2.4", port))
go initServer.Serve(listener)
defer initServer.GracefulStop()
cmd := NewInitCmd()
cmd.Flags().String("workspace", "", "") // register persistent flag manually
cmd.Flags().Bool("force", true, "") // register persistent flag manually
var out bytes.Buffer
cmd.SetOut(&out)
var errOut bytes.Buffer
cmd.SetErr(&errOut)
fs := afero.NewMemMapFs()
fileHandler := file.NewHandler(fs)
require.NoError(fileHandler.WriteJSON(constants.ClusterIDsFilename, existingIDFile, file.OptNone))
cfg := config.Default()
cfg.Image = "v0.0.0" // is the default version of the the CLI (before build injects the real version)
cfg.RemoveProviderAndAttestationExcept(cloudprovider.QEMU)
cfg.Attestation.QEMUVTPM.Measurements[0] = measurements.WithAllBytes(0x00, measurements.Enforce, measurements.PCRMeasurementLength)
cfg.Attestation.QEMUVTPM.Measurements[1] = measurements.WithAllBytes(0x11, measurements.Enforce, measurements.PCRMeasurementLength)
cfg.Attestation.QEMUVTPM.Measurements[2] = measurements.WithAllBytes(0x22, measurements.Enforce, measurements.PCRMeasurementLength)
cfg.Attestation.QEMUVTPM.Measurements[3] = measurements.WithAllBytes(0x33, measurements.Enforce, measurements.PCRMeasurementLength)
cfg.Attestation.QEMUVTPM.Measurements[4] = measurements.WithAllBytes(0x44, measurements.Enforce, measurements.PCRMeasurementLength)
cfg.Attestation.QEMUVTPM.Measurements[9] = measurements.WithAllBytes(0x99, measurements.Enforce, measurements.PCRMeasurementLength)
cfg.Attestation.QEMUVTPM.Measurements[12] = measurements.WithAllBytes(0xcc, measurements.Enforce, measurements.PCRMeasurementLength)
require.NoError(fileHandler.WriteYAML(constants.ConfigFilename, cfg, file.OptNone))
newDialer := func(v atls.Validator) *dialer.Dialer {
validator := &testValidator{
Getter: variant.QEMUVTPM{},
pcrs: cfg.GetAttestationConfig().GetMeasurements(),
}
return dialer.New(nil, validator, netDialer)
}
ctx := context.Background()
ctx, cancel := context.WithTimeout(ctx, 4*time.Second)
defer cancel()
cmd.SetContext(ctx)
i := newInitCmd(nil, nil, fileHandler, &nopSpinner{}, nil, logger.NewTest(t))
err := i.initialize(cmd, newDialer, &stubLicenseClient{}, stubAttestationFetcher{})
assert.Error(err)
// make sure the error is actually a TLS handshake error
assert.Contains(err.Error(), "transport: authentication handshake failed")
}
type testValidator struct {
variant.Getter
pcrs measurements.M
}
func (v *testValidator) Validate(_ context.Context, attDoc []byte, _ []byte) ([]byte, error) {
var attestation struct {
UserData []byte
PCRs map[uint32][]byte
}
if err := json.Unmarshal(attDoc, &attestation); err != nil {
return nil, err
}
for k, pcr := range v.pcrs {
if !bytes.Equal(attestation.PCRs[k], pcr.Expected[:]) {
return nil, errors.New("invalid PCR value")
}
}
return attestation.UserData, nil
}
type testIssuer struct {
variant.Getter
pcrs map[uint32][]byte
}
func (i *testIssuer) Issue(_ context.Context, userData []byte, _ []byte) ([]byte, error) {
return json.Marshal(
struct {
UserData []byte
PCRs map[uint32][]byte
}{
UserData: userData,
PCRs: i.pcrs,
},
)
}
type stubInitServer struct {
res *initproto.InitResponse
initErr error
initproto.UnimplementedAPIServer
}
func (s *stubInitServer) Init(_ *initproto.InitRequest, stream initproto.API_InitServer) error {
_ = stream.Send(s.res)
return s.initErr
}
type stubMerger struct {
envVar string
mergeErr error
}
func (m *stubMerger) mergeConfigs(string, file.Handler) error {
return m.mergeErr
}
func (m *stubMerger) kubeconfigEnvVar() string {
return m.envVar
}
func defaultConfigWithExpectedMeasurements(t *testing.T, conf *config.Config, csp cloudprovider.Provider) *config.Config {
t.Helper()
conf.RemoveProviderAndAttestationExcept(csp)
conf.Image = constants.BinaryVersion().String()
conf.Name = "kubernetes"
var zone, instanceType, diskType string
switch csp {
case cloudprovider.Azure:
conf.Provider.Azure.SubscriptionID = "01234567-0123-0123-0123-0123456789ab"
conf.Provider.Azure.TenantID = "01234567-0123-0123-0123-0123456789ab"
conf.Provider.Azure.Location = "test-location"
conf.Provider.Azure.UserAssignedIdentity = "test-identity"
conf.Provider.Azure.ResourceGroup = "test-resource-group"
conf.Attestation.AzureSEVSNP.Measurements[4] = measurements.WithAllBytes(0x44, measurements.Enforce, measurements.PCRMeasurementLength)
conf.Attestation.AzureSEVSNP.Measurements[9] = measurements.WithAllBytes(0x11, measurements.Enforce, measurements.PCRMeasurementLength)
conf.Attestation.AzureSEVSNP.Measurements[12] = measurements.WithAllBytes(0xcc, measurements.Enforce, measurements.PCRMeasurementLength)
instanceType = "Standard_DC4as_v5"
diskType = "StandardSSD_LRS"
case cloudprovider.GCP:
conf.Provider.GCP.Region = "test-region"
conf.Provider.GCP.Project = "test-project"
conf.Provider.GCP.Zone = "test-zone"
conf.Provider.GCP.ServiceAccountKeyPath = "test-key-path"
conf.Attestation.GCPSEVES.Measurements[4] = measurements.WithAllBytes(0x44, measurements.Enforce, measurements.PCRMeasurementLength)
conf.Attestation.GCPSEVES.Measurements[9] = measurements.WithAllBytes(0x11, measurements.Enforce, measurements.PCRMeasurementLength)
conf.Attestation.GCPSEVES.Measurements[12] = measurements.WithAllBytes(0xcc, measurements.Enforce, measurements.PCRMeasurementLength)
zone = "europe-west3-b"
instanceType = "n2d-standard-4"
diskType = "pd-ssd"
case cloudprovider.QEMU:
conf.Attestation.QEMUVTPM.Measurements[4] = measurements.WithAllBytes(0x44, measurements.Enforce, measurements.PCRMeasurementLength)
conf.Attestation.QEMUVTPM.Measurements[9] = measurements.WithAllBytes(0x11, measurements.Enforce, measurements.PCRMeasurementLength)
conf.Attestation.QEMUVTPM.Measurements[12] = measurements.WithAllBytes(0xcc, measurements.Enforce, measurements.PCRMeasurementLength)
}
for groupName, group := range conf.NodeGroups {
group.Zone = zone
group.InstanceType = instanceType
group.StateDiskType = diskType
conf.NodeGroups[groupName] = group
}
return conf
}
type stubLicenseClient struct{}
func (c *stubLicenseClient) QuotaCheck(_ context.Context, _ license.QuotaCheckRequest) (license.QuotaCheckResponse, error) {
return license.QuotaCheckResponse{
Quota: 25,
}, nil
}
type stubInitClient struct {
res io.Reader
err error
setResNil bool
grpc.ClientStream
}
func (c stubInitClient) Recv() (*initproto.InitResponse, error) {
if c.err != nil {
return &initproto.InitResponse{}, c.err
}
text := make([]byte, 1024)
n, err := c.res.Read(text)
text = text[:n]
res := &initproto.InitResponse{
Kind: &initproto.InitResponse_Log{
Log: &initproto.LogResponseType{
Log: text,
},
},
}
if c.setResNil {
res = &initproto.InitResponse{
Kind: &initproto.InitResponse_Log{
Log: &initproto.LogResponseType{
Log: nil,
},
},
}
}
return res, err
}
type stubHelmInstaller struct{}
func (i *stubHelmInstaller) Install(_ context.Context, _ *helm.Releases) error {
return nil
}
type stubShowCluster struct{}
func (s *stubShowCluster) ShowCluster(_ context.Context, csp cloudprovider.Provider) (terraform.ApplyOutput, error) {
res := terraform.ApplyOutput{}
switch csp {
case cloudprovider.Azure:
res.Azure = &terraform.AzureApplyOutput{}
case cloudprovider.GCP:
res.GCP = &terraform.GCPApplyOutput{}
}
return res, nil
}