// Changes 'b' to a short string >= 'b'
//
// Used to minimize the size of index blocks and other data structures.
func (v *eventStreamComparer) Successor(b []byte) []byte {
keyB, err := newEventStoreKey(b)
if err != nil {
log.Println("A key could not be deserialized:")
log.Println(string(b))
// Always a safe result
return b
}
bcomp := comparer.BytesComparer{}
successor := eventStoreKey{
bcomp.Successor(keyB.groupKey),
nil,
nil,
}
return successor.toBytes()
}
// If 'a' < 'b', changes 'a' to a short string in [a,b).
//
// Used to minimize the size of index blocks and other data structures.
func (v *eventStreamComparer) Separator(a, b []byte) []byte {
keyA, err := newEventStoreKey(a)
if err != nil {
log.Println("A key could not be deserialized:")
log.Println(string(a))
// Always a safe result
return a
}
keyB, err := newEventStoreKey(b)
if err != nil {
log.Println("A key could not be deserialized:")
log.Println(string(b))
// Always a safe result
return a
}
if c := bytes.Compare(keyA.groupKey, keyB.groupKey); c != 0 {
bcomp := comparer.BytesComparer{}
smallerKey := eventStoreKey{
bcomp.Separator(keyA.groupKey, keyB.groupKey),
nil,
nil,
}
return smallerKey.toBytes()
}
// Here we know that keyA.groupKey==keyB.groupKey
if c := bytes.Compare(keyA.key, keyB.key); c != 0 {
bcomp := comparer.BytesComparer{}
smallerKey := eventStoreKey{
keyA.groupKey,
bcomp.Separator(keyA.key, keyB.key),
nil,
}
return smallerKey.toBytes()
}
// Here we know that keyA.key==keyB.key
// Unoptimized result that always works.
// Can't make it shorter than it already is :-/
return a
}