func sortEdgeSets(sets map[string]*gpb.EdgeSet) map[string]*gpb.EdgeSet {
for _, set := range sets {
for _, g := range set.Groups {
sort.Sort(xrefs.ByOrdinal(g.Edge))
}
}
return sets
}
func (d *DB) edges(ctx context.Context, req *xpb.EdgesRequest, edgeFilter func(kind string) bool) (*xpb.EdgesReply, error) {
tickets, err := xrefs.FixTickets(req.Ticket)
if err != nil {
return nil, err
}
pageSize := int(req.PageSize)
if pageSize <= 0 {
pageSize = defaultPageSize
} else if pageSize > maxPageSize {
pageSize = maxPageSize
}
var pageOffset int
if req.PageToken != "" {
rec, err := base64.StdEncoding.DecodeString(req.PageToken)
if err != nil {
return nil, fmt.Errorf("invalid page_token: %q", req.PageToken)
}
var t ipb.PageToken
if err := proto.Unmarshal(rec, &t); err != nil || t.Index < 0 {
return nil, fmt.Errorf("invalid page_token: %q", req.PageToken)
}
pageOffset = int(t.Index)
}
// Select only the edges from the given source tickets
setQ, args := sqlSetQuery(1, tickets)
query := fmt.Sprintf(`
SELECT * FROM AllEdges
WHERE source IN %s`, setQ)
// Filter by edges kinds, if given
if len(req.Kind) > 0 {
kSetQ, kArgs := sqlSetQuery(1+len(args), req.Kind)
query += fmt.Sprintf(`
AND kind IN %s`, kSetQ)
args = append(args, kArgs...)
}
// Scan edge sets/groups in order; necessary for CrossReferences
query += " ORDER BY source, kind, ordinal"
// Seek to the requested page offset (req.PageToken.Index). We don't use
// LIMIT here because we don't yet know how many edges will be filtered by
// edgeFilter.
query += fmt.Sprintf(" OFFSET $%d", len(args)+1)
args = append(args, pageOffset)
rs, err := d.Query(query, args...)
if err != nil {
return nil, fmt.Errorf("error querying for edges: %v", err)
}
defer closeRows(rs)
var scanned int
// edges := map { source -> kind -> target -> ordinal set }
edges := make(map[string]map[string]map[string]map[int32]struct{}, len(tickets))
for count := 0; count < pageSize && rs.Next(); scanned++ {
var source, kind, target string
var ordinal int
if err := rs.Scan(&source, &kind, &target, &ordinal); err != nil {
return nil, fmt.Errorf("edges scan error: %v", err)
}
if edgeFilter != nil && !edgeFilter(kind) {
continue
}
count++
groups, ok := edges[source]
if !ok {
groups = make(map[string]map[string]map[int32]struct{})
edges[source] = groups
}
targets, ok := groups[kind]
if !ok {
targets = make(map[string]map[int32]struct{})
groups[kind] = targets
}
ordinals, ok := targets[target]
if !ok {
ordinals = make(map[int32]struct{})
targets[target] = ordinals
}
ordinals[int32(ordinal)] = struct{}{}
}
reply := &xpb.EdgesReply{EdgeSets: make(map[string]*xpb.EdgeSet, len(edges))}
nodeTickets := stringset.New()
for src, groups := range edges {
gs := make(map[string]*xpb.EdgeSet_Group, len(groups))
nodeTickets.Add(src)
for kind, targets := range groups {
edges := make([]*xpb.EdgeSet_Group_Edge, 0, len(targets))
for ticket, ordinals := range targets {
for ordinal := range ordinals {
edges = append(edges, &xpb.EdgeSet_Group_Edge{
TargetTicket: ticket,
Ordinal: ordinal,
})
}
nodeTickets.Add(ticket)
}
sort.Sort(xrefs.ByOrdinal(edges))
gs[kind] = &xpb.EdgeSet_Group{
Edge: edges,
}
}
reply.EdgeSets[src] = &xpb.EdgeSet{
Groups: gs,
}
}
// If there is another row, there is a NextPageToken.
if rs.Next() {
rec, err := proto.Marshal(&ipb.PageToken{Index: int32(pageOffset + scanned)})
if err != nil {
return nil, fmt.Errorf("internal error: error marshalling page token: %v", err)
}
reply.NextPageToken = base64.StdEncoding.EncodeToString(rec)
}
// TODO(schroederc): faster node lookups
if len(req.Filter) > 0 && len(nodeTickets) > 0 {
nodes, err := d.Nodes(ctx, &xpb.NodesRequest{
Ticket: nodeTickets.Slice(),
Filter: req.Filter,
})
if err != nil {
return nil, fmt.Errorf("error filtering nodes:%v", err)
}
reply.Nodes = nodes.Nodes
}
return reply, nil
}