1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
|
package dispatchv1
import (
"fmt"
"github.com/authzed/spicedb/pkg/spiceerrors"
"github.com/bits-and-blooms/bloom/v3"
"google.golang.org/grpc/codes"
"google.golang.org/grpc/status"
)
func (x *ResolverMeta) RecordTraversal(key string) (possiblyLoop bool, err error) {
if key == "" {
return false, spiceerrors.MustBugf("missing key to be recorded in traversal")
}
if x == nil || len(x.TraversalBloom) == 0 {
return false, status.Error(codes.Internal, fmt.Errorf("required traversal bloom filter is missing").Error())
}
bf := &bloom.BloomFilter{}
if err := bf.UnmarshalBinary(x.TraversalBloom); err != nil {
return false, status.Error(codes.Internal, fmt.Errorf("unable to unmarshall traversal bloom filter: %w", err).Error())
}
if bf.TestString(key) {
return true, nil
}
x.TraversalBloom, err = bf.AddString(key).MarshalBinary()
if err != nil {
return false, err
}
return false, nil
}
const defaultFalsePositiveRate = 0.001
// NewTraversalBloomFilter creates a new bloom filter sized to the provided number of elements and
// with a predefined false-positive ratio of 0.1%.
func NewTraversalBloomFilter(numElements uint) ([]byte, error) {
bf := bloom.NewWithEstimates(numElements, defaultFalsePositiveRate)
emptyBloomFilter, err := bf.MarshalBinary()
if err != nil {
return nil, spiceerrors.MustBugf("unexpected error while serializing empty bloom filter: %s", err.Error())
}
return emptyBloomFilter, nil
}
// MustNewTraversalBloomFilter creates a new bloom filter sized to the provided number of elements and
// with a predefined false-positive ratio of 0.1%.
func MustNewTraversalBloomFilter(numElements uint) []byte {
bf, err := NewTraversalBloomFilter(numElements)
if err != nil {
panic(err)
}
return bf
}
|
