Function populateMutationMap

worker/mutation.go:690–746

populateMutationMap populates a map from group id to the mutation that should be sent to that group.

(src *pb.Mutations)

// populateMutationMap populates a map from group id to the mutation that
// should be sent to that group.
func populateMutationMap(src *pb.Mutations) (map[uint32]*pb.Mutations, error) {
	mm := make(map[uint32]*pb.Mutations)
	for _, edge := range src.Edges {
		gid, err := groups().BelongsTo(edge.Attr)
		if err != nil {
			return nil, err
		}

		mu := mm[gid]
		if mu == nil {
			mu = &pb.Mutations{GroupId: gid}
			mm[gid] = mu
		}
		mu.Edges = append(mu.Edges, edge)
		mu.Metadata = src.Metadata
	}

	for _, schema := range src.Schema {
		gid, err := groups().BelongsTo(schema.Predicate)
		if err != nil {
			return nil, err
		}

		mu := mm[gid]
		if mu == nil {
			mu = &pb.Mutations{GroupId: gid}
			mm[gid] = mu
		}
		mu.Schema = append(mu.Schema, schema)
	}

	if src.DropOp > 0 {
		for _, gid := range groups().KnownGroups() {
			mu := mm[gid]
			if mu == nil {
				mu = &pb.Mutations{GroupId: gid}
				mm[gid] = mu
			}
			mu.DropOp = src.DropOp
			mu.DropValue = src.DropValue
		}
	}

	// Type definitions are sent to all groups.
	if len(src.Types) > 0 {
		for _, gid := range groups().KnownGroups() {
			mu := mm[gid]
			if mu == nil {
				mu = &pb.Mutations{GroupId: gid}
				mm[gid] = mu
			}
			mu.Types = src.Types
		}
	}

	return mm, nil
}