clh: add Client Interface and bootVM test

Add interface with the same methods of client,
this will help to decouple the implementation
and help use to do mock testing.

Add Mock client and add bootVM unit test

Signed-off-by: Jose Carlos Venegas Munoz <jose.carlos.venegas.munoz@intel.com>

virtcontainers/clh.go

@@ -44,6 +44,11 @@ const (
 	clhReady
 )
 
+const (
+	clhStateCreated = "Created"
+	clhStateRunning = "Running"
+)
+
 const (
 	// Values are mandatory by http API
 	// Values based on:
@@ -63,6 +68,19 @@ const (
 	maxClhVcpus           = uint32(64)
 )
 
+// Interface that hides the implementation of openAPI client
+// If the client changes  its methods, this interface should do it as well,
+// The main purpose is to hide the client in an interface to allow mock testing.
+// This is an interface that has to match with OpenAPI CLH client
+type clhClient interface {
+	VmmPingGet(ctx context.Context) (chclient.VmmPingResponse, *http.Response, error)
+	ShutdownVMM(ctx context.Context) (*http.Response, error)
+	CreateVM(ctx context.Context, vmConfig chclient.VmConfig) (*http.Response, error)
+	// No lint: golint suggest to rename to VMInfoGet.
+	VmInfoGet(ctx context.Context) (chclient.VmInfo, *http.Response, error) //nolint:golint
+	BootVM(ctx context.Context) (*http.Response, error)
+}
+
 type CloudHypervisorVersion struct {
 	Major    int
 	Minor    int
@@ -91,7 +109,7 @@ type cloudHypervisor struct {
 	store     *store.VCStore
 	config    HypervisorConfig
 	ctx       context.Context
-	APIClient *chclient.DefaultApiService
+	APIClient clhClient
 	version   CloudHypervisorVersion
 	vmconfig  chclient.VmConfig
 	cmdOutput bytes.Buffer
@@ -927,7 +945,7 @@ func (clh *cloudHypervisor) isClhRunning(timeout uint) (bool, error) {
 
 }
 
-func (clh *cloudHypervisor) client() *chclient.DefaultApiService {
+func (clh *cloudHypervisor) client() clhClient {
 	if clh.APIClient == nil {
 		clh.APIClient = clh.newAPIClient()
 	}
@@ -996,7 +1014,7 @@ func (clh *cloudHypervisor) bootVM(ctx context.Context) error {
 
 	clh.Logger().Debugf("VM state after create: %#v", info)
 
-	if info.State != "Created" {
+	if info.State != clhStateCreated {
 		return fmt.Errorf("VM state is not 'Created' after 'CreateVM'")
 	}
 
@@ -1015,7 +1033,7 @@ func (clh *cloudHypervisor) bootVM(ctx context.Context) error {
 
 	clh.Logger().Debugf("VM state after boot: %#v", info)
 
-	if info.State != "Running" {
+	if info.State != clhStateRunning {
 		return fmt.Errorf("VM state is not 'Running' after 'BootVM'")
 	}
 

virtcontainers/clh_test.go

@@ -6,10 +6,41 @@
 package virtcontainers
 
 import (
-	"github.com/stretchr/testify/assert"
+	"context"
+	"net/http"
 	"testing"
+
+	chclient "github.com/kata-containers/runtime/virtcontainers/pkg/cloud-hypervisor/client"
+	"github.com/stretchr/testify/assert"
 )
 
+type clhClientMock struct {
+	vmInfo chclient.VmInfo
+}
+
+func (c *clhClientMock) VmmPingGet(ctx context.Context) (chclient.VmmPingResponse, *http.Response, error) {
+	return chclient.VmmPingResponse{}, nil, nil
+}
+
+func (c *clhClientMock) ShutdownVMM(ctx context.Context) (*http.Response, error) {
+	return nil, nil
+}
+
+func (c *clhClientMock) CreateVM(ctx context.Context, vmConfig chclient.VmConfig) (*http.Response, error) {
+	c.vmInfo.State = clhStateCreated
+	return nil, nil
+}
+
+//nolint:golint
+func (c *clhClientMock) VmInfoGet(ctx context.Context) (chclient.VmInfo, *http.Response, error) {
+	return c.vmInfo, nil, nil
+}
+
+func (c *clhClientMock) BootVM(ctx context.Context) (*http.Response, error) {
+	c.vmInfo.State = clhStateRunning
+	return nil, nil
+}
+
 func TestCloudHypervisorAddVSock(t *testing.T) {
 	assert := assert.New(t)
 	clh := cloudHypervisor{}
@@ -22,3 +53,12 @@ func TestCloudHypervisorAddVSock(t *testing.T) {
 	assert.Equal(clh.vmconfig.Vsock[1].Cid, int64(2))
 	assert.Equal(clh.vmconfig.Vsock[1].Sock, "path2")
 }
+
+func TestCloudHypervisorBootVM(t *testing.T) {
+	clh := &cloudHypervisor{}
+	clh.APIClient = &clhClientMock{}
+	var ctx context.Context
+	if err := clh.bootVM(ctx); err != nil {
+		t.Errorf("cloudHypervisor.bootVM() error = %v", err)
+	}
+}