github.com/Finschia/finschia-sdk@v0.48.1/x/staking/keeper/historical_info.go (about)

     1  package keeper
     2  
     3  import (
     4  	sdk "github.com/Finschia/finschia-sdk/types"
     5  	"github.com/Finschia/finschia-sdk/x/staking/types"
     6  )
     7  
     8  // GetHistoricalInfo gets the historical info at a given height
     9  func (k Keeper) GetHistoricalInfo(ctx sdk.Context, height int64) (types.HistoricalInfo, bool) {
    10  	store := ctx.KVStore(k.storeKey)
    11  	key := types.GetHistoricalInfoKey(height)
    12  
    13  	value := store.Get(key)
    14  	if value == nil {
    15  		return types.HistoricalInfo{}, false
    16  	}
    17  
    18  	return types.MustUnmarshalHistoricalInfo(k.cdc, value), true
    19  }
    20  
    21  // SetHistoricalInfo sets the historical info at a given height
    22  func (k Keeper) SetHistoricalInfo(ctx sdk.Context, height int64, hi *types.HistoricalInfo) {
    23  	store := ctx.KVStore(k.storeKey)
    24  	key := types.GetHistoricalInfoKey(height)
    25  	value := k.cdc.MustMarshal(hi)
    26  	store.Set(key, value)
    27  }
    28  
    29  // DeleteHistoricalInfo deletes the historical info at a given height
    30  func (k Keeper) DeleteHistoricalInfo(ctx sdk.Context, height int64) {
    31  	store := ctx.KVStore(k.storeKey)
    32  	key := types.GetHistoricalInfoKey(height)
    33  
    34  	store.Delete(key)
    35  }
    36  
    37  // IterateHistoricalInfo provides an interator over all stored HistoricalInfo
    38  //
    39  //	objects. For each HistoricalInfo object, cb will be called. If the cb returns
    40  //
    41  // true, the iterator will close and stop.
    42  func (k Keeper) IterateHistoricalInfo(ctx sdk.Context, cb func(types.HistoricalInfo) bool) {
    43  	store := ctx.KVStore(k.storeKey)
    44  
    45  	iterator := sdk.KVStorePrefixIterator(store, types.HistoricalInfoKey)
    46  	defer iterator.Close()
    47  
    48  	for ; iterator.Valid(); iterator.Next() {
    49  		histInfo := types.MustUnmarshalHistoricalInfo(k.cdc, iterator.Value())
    50  		if cb(histInfo) {
    51  			break
    52  		}
    53  	}
    54  }
    55  
    56  // GetAllHistoricalInfo returns all stored HistoricalInfo objects.
    57  func (k Keeper) GetAllHistoricalInfo(ctx sdk.Context) []types.HistoricalInfo {
    58  	var infos []types.HistoricalInfo
    59  
    60  	k.IterateHistoricalInfo(ctx, func(histInfo types.HistoricalInfo) bool {
    61  		infos = append(infos, histInfo)
    62  		return false
    63  	})
    64  
    65  	return infos
    66  }
    67  
    68  // TrackHistoricalInfo saves the latest historical-info and deletes the oldest
    69  // heights that are below pruning height
    70  func (k Keeper) TrackHistoricalInfo(ctx sdk.Context) {
    71  	entryNum := k.HistoricalEntries(ctx)
    72  
    73  	// Prune store to ensure we only have parameter-defined historical entries.
    74  	// In most cases, this will involve removing a single historical entry.
    75  	// In the rare scenario when the historical entries gets reduced to a lower value k'
    76  	// from the original value k. k - k' entries must be deleted from the store.
    77  	// Since the entries to be deleted are always in a continuous range, we can iterate
    78  	// over the historical entries starting from the most recent version to be pruned
    79  	// and then return at the first empty entry.
    80  	for i := ctx.BlockHeight() - int64(entryNum); i >= 0; i-- {
    81  		_, found := k.GetHistoricalInfo(ctx, i)
    82  		if found {
    83  			k.DeleteHistoricalInfo(ctx, i)
    84  		} else {
    85  			break
    86  		}
    87  	}
    88  
    89  	// if there is no need to persist historicalInfo, return
    90  	if entryNum == 0 {
    91  		return
    92  	}
    93  
    94  	// Create HistoricalInfo struct
    95  	lastVals := k.GetLastValidators(ctx)
    96  	historicalEntry := types.NewHistoricalInfo(ctx.BlockHeader(), lastVals, k.PowerReduction(ctx))
    97  
    98  	// Set latest HistoricalInfo at current height
    99  	k.SetHistoricalInfo(ctx, ctx.BlockHeight(), &historicalEntry)
   100  }