Golang Layer.ID方法代碼示例

// Internally, only Feature additions/removals are stored for each layer. If a layer has a parent,
// the Feature list will be compared to the parent's Feature list and the difference will be stored.
// Note that when the Namespace of a layer differs from its parent, it is expected that several
// Feature that were already included a parent will have their Namespace updated as well
// (happens when Feature detectors relies on the detected layer Namespace). However, if the listed
// Feature has the same Name/Version as its parent, InsertLayer considers that the Feature hasn't
// been modified.
func (pgSQL *pgSQL) InsertLayer(layer database.Layer) error {
	tf := time.Now()

	// Verify parameters
	if layer.Name == "" {
		log.Warning("could not insert a layer which has an empty Name")
		return cerrors.NewBadRequestError("could not insert a layer which has an empty Name")
	}

	// Get a potentially existing layer.
	existingLayer, err := pgSQL.FindLayer(layer.Name, true, false)
	if err != nil && err != cerrors.ErrNotFound {
		return err
	} else if err == nil {
		if existingLayer.EngineVersion >= layer.EngineVersion {
			// The layer exists and has an equal or higher engine version, do nothing.
			return nil
		}

		layer.ID = existingLayer.ID
	}

	// We do `defer observeQueryTime` here because we don't want to observe existing layers.
	defer observeQueryTime("InsertLayer", "all", tf)

	// Get parent ID.
	var parentID zero.Int
	if layer.Parent != nil {
		if layer.Parent.ID == 0 {
			log.Warning("Parent is expected to be retrieved from database when inserting a layer.")
			return cerrors.NewBadRequestError("Parent is expected to be retrieved from database when inserting a layer.")
		}

		parentID = zero.IntFrom(int64(layer.Parent.ID))
	}

	// Find or insert namespace if provided.
	var namespaceID zero.Int
	if layer.Namespace != nil {
		n, err := pgSQL.insertNamespace(*layer.Namespace)
		if err != nil {
			return err
		}
		namespaceID = zero.IntFrom(int64(n))
	} else if layer.Namespace == nil && layer.Parent != nil {
		// Import the Namespace from the parent if it has one and this layer doesn't specify one.
		if layer.Parent.Namespace != nil {
			namespaceID = zero.IntFrom(int64(layer.Parent.Namespace.ID))
		}
	}

	// Begin transaction.
	tx, err := pgSQL.Begin()
	if err != nil {
		tx.Rollback()
		return handleError("InsertLayer.Begin()", err)
	}

	if layer.ID == 0 {
		// Insert a new layer.
		err = tx.QueryRow(insertLayer, layer.Name, layer.EngineVersion, parentID, namespaceID).
			Scan(&layer.ID)
		if err != nil {
			tx.Rollback()

			if isErrUniqueViolation(err) {
				// Ignore this error, another process collided.
				log.Debug("Attempted to insert duplicate layer.")
				return nil
			}
			return handleError("insertLayer", err)
		}
	} else {
		// Update an existing layer.
		_, err = tx.Exec(updateLayer, layer.ID, layer.EngineVersion, namespaceID)
		if err != nil {
			tx.Rollback()
			return handleError("updateLayer", err)
		}

		// Remove all existing Layer_diff_FeatureVersion.
		_, err = tx.Exec(removeLayerDiffFeatureVersion, layer.ID)
		if err != nil {
			tx.Rollback()
			return handleError("removeLayerDiffFeatureVersion", err)
		}
	}

	// Update Layer_diff_FeatureVersion now.
	err = pgSQL.updateDiffFeatureVersions(tx, &layer, &existingLayer)
	if err != nil {
		tx.Rollback()
		return err
//.........這裏部分代碼省略.........