cosmos-sdk/x/staking/keeper/historical_info.go

72 lines
2.3 KiB
Go

package keeper
import (
sdk "github.com/cosmos/cosmos-sdk/types"
"github.com/cosmos/cosmos-sdk/x/staking/types"
)
// GetHistoricalInfo gets the historical info at a given height
func (k Keeper) GetHistoricalInfo(ctx sdk.Context, height int64) (types.HistoricalInfo, bool) {
store := ctx.KVStore(k.storeKey)
key := types.GetHistoricalInfoKey(height)
value := store.Get(key)
if value == nil {
return types.HistoricalInfo{}, false
}
hi := types.MustUnmarshalHistoricalInfo(k.cdc, value)
return hi, true
}
// SetHistoricalInfo sets the historical info at a given height
func (k Keeper) SetHistoricalInfo(ctx sdk.Context, height int64, hi types.HistoricalInfo) {
store := ctx.KVStore(k.storeKey)
key := types.GetHistoricalInfoKey(height)
value := types.MustMarshalHistoricalInfo(k.cdc, hi)
store.Set(key, value)
}
// DeleteHistoricalInfo deletes the historical info at a given height
func (k Keeper) DeleteHistoricalInfo(ctx sdk.Context, height int64) {
store := ctx.KVStore(k.storeKey)
key := types.GetHistoricalInfoKey(height)
store.Delete(key)
}
// TrackHistoricalInfo saves the latest historical-info and deletes the oldest
// heights that are below pruning height
func (k Keeper) TrackHistoricalInfo(ctx sdk.Context) {
entryNum := k.HistoricalEntries(ctx)
// Prune store to ensure we only have parameter-defined historical entries.
// In most cases, this will involve removing a single historical entry.
// In the rare scenario when the historical entries gets reduced to a lower value k'
// from the original value k. k - k' entries must be deleted from the store.
// Since the entries to be deleted are always in a continuous range, we can iterate
// over the historical entries starting from the most recent version to be pruned
// and then return at the first empty entry.
for i := ctx.BlockHeight() - int64(entryNum); i >= 0; i-- {
_, found := k.GetHistoricalInfo(ctx, i)
if found {
k.DeleteHistoricalInfo(ctx, i)
} else {
break
}
}
// if there is no need to persist historicalInfo, return
if entryNum == 0 {
return
}
// Create HistoricalInfo struct
lastVals := k.GetLastValidators(ctx)
historicalEntry := types.NewHistoricalInfo(ctx.BlockHeader(), lastVals)
// Set latest HistoricalInfo at current height
k.SetHistoricalInfo(ctx, ctx.BlockHeight(), historicalEntry)
}