Add Go backend support for PVC subPath

- Read subPath from protobuf in makeVolumeMountPatch
- Pass subPath to Kubernetes VolumeMount
- Add test case for PVC mount with subPath
- Regenerate Go protobuf code

Signed-off-by: vmridul <vermamridul1302@gmail.com>

Author: vmridul

backend/src/v2/driver/k8s.go

@@ -1011,12 +1011,14 @@ func makeVolumeMountPatch(
 		pvcName := resolvedPvcName.GetStringValue()
 
 		pvcMountPath := pvcMount.GetMountPath()
+		pvcSubPath := pvcMount.GetSubPath()
 		if pvcName == "" || pvcMountPath == "" {
 			return nil, nil, fmt.Errorf("failed to mount volume, missing mountpath or pvc name")
 		}
 		volumeMount := k8score.VolumeMount{
 			Name:      pvcName,
 			MountPath: pvcMountPath,
+			SubPath:   pvcSubPath,
 		}
 		volume := k8score.Volume{
 			Name: pvcName,

backend/src/v2/driver/k8s_test.go

@@ -27,6 +27,7 @@ func Test_makeVolumeMountPatch(t *testing.T) {
 		args        args
 		wantPath    string
 		wantName    string
+		wantSubPath string
 		inputParams map[string]*structpb.Value
 	}{
 		{
@@ -43,6 +44,7 @@ func Test_makeVolumeMountPatch(t *testing.T) {
 			},
 			"/mnt/path",
 			"pvc-name",
+			"",
 			nil,
 		},
 		{
@@ -60,6 +62,7 @@ func Test_makeVolumeMountPatch(t *testing.T) {
 			},
 			"/mnt/path",
 			"pvc-name",
+			"",
 			nil,
 		},
 		{
@@ -76,10 +79,29 @@ func Test_makeVolumeMountPatch(t *testing.T) {
 			},
 			"/mnt/path",
 			"pvc-name",
+			"",
 			map[string]*structpb.Value{
 				"param_1": structpb.NewStringValue("pvc-name"),
 			},
 		},
+		{
+			"pvc with subPath",
+			args{
+				[]*kubernetesplatform.PvcMount{
+					{
+						MountPath:        "/mnt/path",
+						SubPath:          "logs/experiment1",
+						PvcNameParameter: inputParamConstant("pvc-name"),
+					},
+				},
+				nil,
+				nil,
+			},
+			"/mnt/path",
+			"pvc-name",
+			"logs/experiment1",
+			nil,
+		},
 	}
 
 	for _, tt := range tests {
@@ -100,6 +122,7 @@ func Test_makeVolumeMountPatch(t *testing.T) {
 			assert.Equal(t, volumeMounts[0].Name, tt.wantName)
 			assert.Equal(t, volumes[0].Name, tt.wantName)
 			assert.Equal(t, volumes[0].PersistentVolumeClaim.ClaimName, tt.wantName)
+			assert.Equal(t, volumeMounts[0].SubPath, tt.wantSubPath)
 		})
 	}
 }