feat: Add optional "parent" field to Device objects.

clients/http/device.go

@@ -66,6 +66,22 @@ func (dc DeviceClient) AllDevices(ctx context.Context, labels []string, offset i
 	return res, nil
 }
 
+func (dc DeviceClient) AllDevicesWithChildren(ctx context.Context, parent string, maxLevels uint, labels []string, offset int, limit int) (res responses.MultiDevicesResponse, err errors.EdgeX) {
+	requestParams := url.Values{}
+	if len(labels) > 0 {
+		requestParams.Set(common.Labels, strings.Join(labels, common.CommaSeparator))
+	}
+	requestParams.Set(common.DescendantsOf, parent)
+	requestParams.Set(common.MaxLevels, strconv.FormatUint(uint64(maxLevels), 10))
+	requestParams.Set(common.Offset, strconv.Itoa(offset))
+	requestParams.Set(common.Limit, strconv.Itoa(limit))
+	err = utils.GetRequest(ctx, &res, dc.baseUrl, common.ApiAllDeviceRoute, requestParams, dc.authInjector)
+	if err != nil {
+		return res, errors.NewCommonEdgeXWrapper(err)
+	}
+	return res, nil
+}
+
 func (dc DeviceClient) DeviceNameExists(ctx context.Context, name string) (res dtoCommon.BaseResponse, err errors.EdgeX) {
 	path := common.NewPathBuilder().EnableNameFieldEscape(dc.enableNameFieldEscape).
 		SetPath(common.ApiDeviceRoute).SetPath(common.Check).SetPath(common.Name).SetNameFieldPath(name).BuildPath()

clients/http/device_test.go

@@ -101,3 +101,12 @@ func TestQueryDevicesByServiceName(t *testing.T) {
 	require.NoError(t, err)
 	require.IsType(t, responses.MultiDevicesResponse{}, res)
 }
+
+func TestQueryDeviceTree(t *testing.T) {
+	ts := newTestServer(http.MethodGet, common.ApiAllDeviceRoute, responses.MultiDevicesResponse{})
+	defer ts.Close()
+	client := NewDeviceClient(ts.URL, NewNullAuthenticationInjector(), false)
+	res, err := client.AllDevicesWithChildren(context.Background(), "MyRoot", 3, []string{"label1", "label2"}, 1, 10)
+	require.NoError(t, err)
+	require.IsType(t, responses.MultiDevicesResponse{}, res)
+}

clients/interfaces/device.go

@@ -25,6 +25,13 @@ type DeviceClient interface {
 	// offset: The number of items to skip before starting to collect the result set. Default is 0.
 	// limit: The number of items to return. Specify -1 will return all remaining items after offset. The maximum will be the MaxResultCount as defined in the configuration of service. Default is 20.
 	AllDevices(ctx context.Context, labels []string, offset int, limit int) (responses.MultiDevicesResponse, errors.EdgeX)
+	// AllDevicesWithChildren returns all devices who have parent, grandparent, etc. of the
+	// given device name. Devices can also be filtered by labels.
+	// Device tree is descended at most maxLevels. If maxLevels is 0, there is no limit.
+	// The result can be limited in a certain range by specifying the offset and limit parameters.
+	// offset: The number of items to skip before starting to collect the result set. Default is 0.
+	// limit: The number of items to return. Specify -1 will return all remaining items after offset. The maximum will be the MaxResultCount as defined in the configuration of service. Default is 20.
+	AllDevicesWithChildren(ctx context.Context, parent string, maxLevels uint, labels []string, offset int, limit int) (responses.MultiDevicesResponse, errors.EdgeX)
 	// DeviceNameExists checks whether the device exists.
 	DeviceNameExists(ctx context.Context, name string) (common.BaseResponse, errors.EdgeX)
 	// DeviceByName returns a device by device name.

common/constants.go

@@ -185,16 +185,18 @@ const (
 	Key           = "key"
 	ServiceId     = "serviceId"
 
-	Offset       = "offset"         //query string to specify the number of items to skip before starting to collect the result set.
-	Limit        = "limit"          //query string to specify the numbers of items to return
-	Labels       = "labels"         //query string to specify associated user-defined labels for querying a given object. More than one label may be specified via a comma-delimited list
-	PushEvent    = "ds-pushevent"   //query string to specify if an event should be pushed to the EdgeX system
-	ReturnEvent  = "ds-returnevent" //query string to specify if an event should be returned from device service
-	RegexCommand = "ds-regexcmd"    //query string to specify if the command name is in regular expression format
-	Flatten      = "flatten"        //query string to specify if the request json payload should be flattened to update multiple keys with the same prefix
-	KeyOnly      = "keyOnly"        //query string to specify if the response will only return the keys of the specified query key prefix, without values and metadata
-	Plaintext    = "plaintext"      //query string to specify if the response will return the stored plain text value of the key(s) without any encoding
-	Deregistered = "deregistered"   //query string to specify if the response will return the registries of deregistered services
+	Offset        = "offset"         //query string to specify the number of items to skip before starting to collect the result set.
+	Limit         = "limit"          //query string to specify the numbers of items to return
+	Labels        = "labels"         //query string to specify associated user-defined labels for querying a given object. More than one label may be specified via a comma-delimited list
+	PushEvent     = "ds-pushevent"   //query string to specify if an event should be pushed to the EdgeX system
+	ReturnEvent   = "ds-returnevent" //query string to specify if an event should be returned from device service
+	RegexCommand  = "ds-regexcmd"    //query string to specify if the command name is in regular expression format
+	DescendantsOf = "descendantsOf"  //Limit returned devices to those who have parent, grandparent, etc. of the given device name
+	MaxLevels     = "maxLevels"      //Limit returned devices to this many levels below 'descendantsOf' (0=unlimited)
+	Flatten       = "flatten"        //query string to specify if the request json payload should be flattened to update multiple keys with the same prefix
+	KeyOnly       = "keyOnly"        //query string to specify if the response will only return the keys of the specified query key prefix, without values and metadata
+	Plaintext     = "plaintext"      //query string to specify if the response will return the stored plain text value of the key(s) without any encoding
+	Deregistered  = "deregistered"   //query string to specify if the response will return the registries of deregistered services
 )
 
 // Constants related to the default value of query strings in the v3 service APIs

dtos/device.go

@@ -13,6 +13,7 @@ type Device struct {
 	DBTimestamp    `json:",inline"`
 	Id             string                        `json:"id,omitempty" yaml:"id,omitempty" validate:"omitempty,uuid"`
 	Name           string                        `json:"name" yaml:"name" validate:"required,edgex-dto-none-empty-string"`
+	Parent         string                        `json:"parent,omitempty" yaml:"parent,omitempty"`
 	Description    string                        `json:"description,omitempty" yaml:"description,omitempty"`
 	AdminState     string                        `json:"adminState" yaml:"adminState" validate:"oneof='LOCKED' 'UNLOCKED'"`
 	OperatingState string                        `json:"operatingState" yaml:"operatingState" validate:"oneof='UP' 'DOWN' 'UNKNOWN'"`
@@ -29,6 +30,7 @@ type Device struct {
 type UpdateDevice struct {
 	Id             *string                       `json:"id" validate:"required_without=Name,edgex-dto-uuid"`
 	Name           *string                       `json:"name" validate:"required_without=Id,edgex-dto-none-empty-string"`
+	Parent         *string                       `json:"parent,omitempty" yaml:"parent,omitempty"`
 	Description    *string                       `json:"description" validate:"omitempty"`
 	AdminState     *string                       `json:"adminState" validate:"omitempty,oneof='LOCKED' 'UNLOCKED'"`
 	OperatingState *string                       `json:"operatingState" validate:"omitempty,oneof='UP' 'DOWN' 'UNKNOWN'"`
@@ -47,6 +49,7 @@ func ToDeviceModel(dto Device) models.Device {
 	var d models.Device
 	d.Id = dto.Id
 	d.Name = dto.Name
+	d.Parent = dto.Parent
 	d.Description = dto.Description
 	d.ServiceName = dto.ServiceName
 	d.ProfileName = dto.ProfileName
@@ -67,6 +70,7 @@ func FromDeviceModelToDTO(d models.Device) Device {
 	dto.DBTimestamp = DBTimestamp(d.DBTimestamp)
 	dto.Id = d.Id
 	dto.Name = d.Name
+	dto.Parent = d.Parent
 	dto.Description = d.Description
 	dto.ServiceName = d.ServiceName
 	dto.ProfileName = d.ProfileName
@@ -88,6 +92,7 @@ func FromDeviceModelToUpdateDTO(d models.Device) UpdateDevice {
 	dto := UpdateDevice{
 		Id:             &d.Id,
 		Name:           &d.Name,
+		Parent:         &d.Parent,
 		Description:    &d.Description,
 		AdminState:     &adminState,
 		OperatingState: &operatingState,