frostfs-contract/common/vote.go
Leonard Lyubich c3efe152d6 [#42] Share Vote/RemoteVotes between contracts
Replace vote/remoteVotes functions from all contracts (except alphabet) to
common package. Additionally replace setSerialized and bytesEqual. Create
InitVote function and use it in NeoFS and Netmap contracts.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2021-02-04 10:31:24 +03:00

104 lines
2.4 KiB
Go

package common
import (
"github.com/nspcc-dev/neo-go/pkg/interop/binary"
"github.com/nspcc-dev/neo-go/pkg/interop/blockchain"
"github.com/nspcc-dev/neo-go/pkg/interop/storage"
"github.com/nspcc-dev/neo-go/pkg/interop/util"
)
const voteKey = "ballots"
const blockDiff = 20 // change base on performance evaluation
func InitVote(ctx storage.Context) {
SetSerialized(ctx, voteKey, []Ballot{})
}
// Vote adds ballot for the decision with specific 'id' and returns amount
// on unique voters for that decision.
func Vote(ctx storage.Context, id, from []byte) int {
var (
newCandidates []Ballot
candidates = getBallots(ctx)
found = -1
blockHeight = blockchain.GetHeight()
)
for i := 0; i < len(candidates); i++ {
cnd := candidates[i]
if blockHeight-cnd.Height > blockDiff {
continue
}
if BytesEqual(cnd.ID, id) {
voters := cnd.Voters
for j := range voters {
if BytesEqual(voters[j], from) {
return len(voters)
}
}
voters = append(voters, from)
cnd = Ballot{ID: id, Voters: voters, Height: blockHeight}
found = len(voters)
}
newCandidates = append(newCandidates, cnd)
}
if found < 0 {
voters := [][]byte{from}
newCandidates = append(newCandidates, Ballot{
ID: id,
Voters: voters,
Height: blockHeight})
found = 1
}
SetSerialized(ctx, voteKey, newCandidates)
return found
}
// RemoveVotes clears ballots of the decision that has been accepted by
// inner ring nodes.
func RemoveVotes(ctx storage.Context, id []byte) {
var (
newCandidates []Ballot
candidates = getBallots(ctx)
)
for i := 0; i < len(candidates); i++ {
cnd := candidates[i]
if !BytesEqual(cnd.ID, id) {
newCandidates = append(newCandidates, cnd)
}
}
SetSerialized(ctx, voteKey, newCandidates)
}
// getBallots returns deserialized slice of vote ballots.
func getBallots(ctx storage.Context) []Ballot {
data := storage.Get(ctx, voteKey)
if data != nil {
return binary.Deserialize(data.([]byte)).([]Ballot)
}
return []Ballot{}
}
// BytesEqual compares two slice of bytes by wrapping them into strings,
// which is necessary with new util.Equal interop behaviour, see neo-go#1176.
func BytesEqual(a []byte, b []byte) bool {
return util.Equals(string(a), string(b))
}
// SetSerialized serializes data and puts it into contract storage.
func SetSerialized(ctx storage.Context, key interface{}, value interface{}) {
data := binary.Serialize(value)
storage.Put(ctx, key, data)
}