src/server/pkg/dag/dag.go
func (d *DAG) NewNode(id string, parents []string) {
	d.parents[id] = parents
	for _, parentID := range parents {
		d.children[parentID] = append(d.children[parentID], id)
		d.leaves[parentID] = false
	}
	if _, ok := d.leaves[id]; !ok {
		d.leaves[id] = true
	}
}
func (d *DAG) NewNode(id string, parents []string) {
	d.parents[id] = parents
	for _, parentID := range parents {
		d.children[parentID] = append(d.children[parentID], id)
		d.leaves[parentID] = false
	}
	if _, ok := d.leaves[id]; !ok {
		d.leaves[id] = true
	}
}
// NewNode adds a node to d.