csi: Add NodeStageVolume to fake client

plugins/csi/fake/client.go

@@ -50,6 +50,9 @@ type Client struct {
 	NextNodeGetInfoResponse *csi.NodeGetInfoResponse
 	NextNodeGetInfoErr      error
 	NodeGetInfoCallCount    int64
+
+	NextNodeStageVolumeErr   error
+	NodeStageVolumeCallCount int64
 }
 
 // PluginInfo describes the type and version of a plugin.
@@ -146,6 +149,18 @@ func (c *Client) NodeGetInfo(ctx context.Context) (*csi.NodeGetInfoResponse, err
 	return c.NextNodeGetInfoResponse, c.NextNodeGetInfoErr
 }
 
+// NodeStageVolume is used when a plugin has the STAGE_UNSTAGE volume capability
+// to prepare a volume for usage on a host. If err == nil, the response should
+// be assumed to be successful.
+func (c *Client) NodeStageVolume(ctx context.Context, volumeID string, publishContext map[string]string, stagingTargetPath string, capabilities *csi.VolumeCapability) error {
+	c.Mu.Lock()
+	defer c.Mu.Unlock()
+
+	c.NodeStageVolumeCallCount++
+
+	return c.NextNodeStageVolumeErr
+}
+
 // Shutdown the client and ensure any connections are cleaned up.
 func (c *Client) Close() error {
 	return nil

plugins/csi/testing/client.go

@@ -95,6 +95,7 @@ func (f *NodeClient) Reset() {
 	f.NextErr = nil
 	f.NextCapabilitiesResponse = nil
 	f.NextGetInfoResponse = nil
+	f.NextStageVolumeResponse = nil
 }
 
 func (c *NodeClient) NodeGetCapabilities(ctx context.Context, in *csipbv1.NodeGetCapabilitiesRequest, opts ...grpc.CallOption) (*csipbv1.NodeGetCapabilitiesResponse, error) {