forked from extern/smegmesh
81 lines
1.5 KiB
Go
81 lines
1.5 KiB
Go
package crdt
|
|
|
|
import (
|
|
"sync"
|
|
|
|
"github.com/tim-beatham/wgmesh/pkg/lib"
|
|
)
|
|
|
|
// Vector clock defines an abstract data type
|
|
// for a vector clock implementation
|
|
type VectorClock[K comparable] struct {
|
|
vectors map[K]uint64
|
|
lock sync.RWMutex
|
|
processID K
|
|
}
|
|
|
|
// IncrementClock: increments the node's value in the vector clock
|
|
func (m *VectorClock[K]) IncrementClock() uint64 {
|
|
maxClock := uint64(0)
|
|
m.lock.Lock()
|
|
|
|
for _, value := range m.vectors {
|
|
maxClock = max(maxClock, value)
|
|
}
|
|
|
|
m.vectors[m.processID] = maxClock + 1
|
|
m.lock.Unlock()
|
|
return maxClock
|
|
}
|
|
|
|
// GetHash: gets the hash of the vector clock used to determine if there
|
|
// are any changes
|
|
func (m *VectorClock[K]) GetHash() uint64 {
|
|
m.lock.RLock()
|
|
|
|
sum := lib.Reduce(uint64(0), lib.MapValues(m.vectors), func(sum uint64, current uint64) uint64 {
|
|
return current + sum
|
|
})
|
|
|
|
m.lock.RUnlock()
|
|
return sum
|
|
}
|
|
|
|
func (m *VectorClock[K]) Prune() {
|
|
outliers := lib.GetOutliers(m.vectors, 0.05)
|
|
|
|
m.lock.Lock()
|
|
|
|
for _, outlier := range outliers {
|
|
delete(m.vectors, outlier)
|
|
}
|
|
|
|
m.lock.Unlock()
|
|
}
|
|
|
|
func (m *VectorClock[K]) Put(key K, value uint64) {
|
|
m.lock.Lock()
|
|
m.vectors[key] = max(value, m.vectors[key])
|
|
m.lock.Unlock()
|
|
}
|
|
|
|
func (m *VectorClock[K]) GetClock() map[K]uint64 {
|
|
clock := make(map[K]uint64)
|
|
|
|
m.lock.RLock()
|
|
|
|
for key, value := range clock {
|
|
clock[key] = value
|
|
}
|
|
|
|
m.lock.RUnlock()
|
|
return clock
|
|
}
|
|
|
|
func NewVectorClock[K comparable](processID K) *VectorClock[K] {
|
|
return &VectorClock[K]{
|
|
vectors: make(map[K]uint64),
|
|
processID: processID,
|
|
}
|
|
}
|