Method EdgesTo

pkg/search/handler.go:771–844

EdgesTo returns edges that reference req.RefTo. It filters out since-deleted permanode edges.

(req *EdgesRequest)

// EdgesTo returns edges that reference req.RefTo.
// It filters out since-deleted permanode edges.
func (h *Handler) EdgesTo(req *EdgesRequest) (*EdgesResponse, error) {
	ctx := context.TODO()
	h.index.RLock()
	defer h.index.RUnlock()

	toRef := req.ToRef
	toRefStr := toRef.String()
	var edgeItems []*EdgeItem

	edges, err := h.index.EdgesTo(toRef, nil)
	if err != nil {
		panic(err)
	}

	type edgeOrError struct {
		edge *EdgeItem // or nil
		err  error
	}
	resc := make(chan edgeOrError)
	verify := func(edge *camtypes.Edge) {
		db, err := h.NewDescribeRequest().DescribeSync(ctx, edge.From)
		if err != nil {
			resc <- edgeOrError{err: err}
			return
		}
		found := false
		if db.Permanode != nil {
			for attr, vv := range db.Permanode.Attr {
				if index.IsBlobReferenceAttribute(attr) {
					for _, v := range vv {
						if v == toRefStr {
							found = true
						}
					}
				}
			}
		}
		var ei *EdgeItem
		if found {
			ei = &EdgeItem{
				From:     edge.From,
				FromType: schema.TypePermanode,
			}
		}
		resc <- edgeOrError{edge: ei}
	}
	verifying := 0
	for _, edge := range edges {
		if edge.FromType == schema.TypePermanode {
			verifying++
			go verify(edge)
			continue
		}
		ei := &EdgeItem{
			From:     edge.From,
			FromType: edge.FromType,
		}
		edgeItems = append(edgeItems, ei)