package keeper import ( "fmt" "time" "github.com/cosmos/cosmos-sdk/store/prefix" sdk "github.com/cosmos/cosmos-sdk/types" "github.com/kava-labs/kava/x/auction/types" ) // RegisterInvariants registers all staking invariants func RegisterInvariants(ir sdk.InvariantRegistry, k Keeper) { ir.RegisterRoute(types.ModuleName, "module-account", ModuleAccountInvariants(k)) ir.RegisterRoute(types.ModuleName, "valid-auctions", ValidAuctionInvariant(k)) ir.RegisterRoute(types.ModuleName, "valid-index", ValidIndexInvariant(k)) } // ModuleAccountInvariant checks that the module account's coins matches those stored in auctions func ModuleAccountInvariants(k Keeper) sdk.Invariant { return func(ctx sdk.Context) (string, bool) { totalAuctionCoins := sdk.NewCoins() k.IterateAuctions(ctx, func(auction types.Auction) bool { a, ok := auction.(types.GenesisAuction) if !ok { panic("stored auction type does not fulfill GenesisAuction interface") } totalAuctionCoins = totalAuctionCoins.Add(a.GetModuleAccountCoins()) return false }) moduleAccCoins := k.supplyKeeper.GetModuleAccount(ctx, types.ModuleName).GetCoins() broken := !moduleAccCoins.IsEqual(totalAuctionCoins) invariantMessage := sdk.FormatInvariant( types.ModuleName, "module account", fmt.Sprintf( "\texpected ModuleAccount coins: %s\n"+ "\tactual ModuleAccount coins: %s\n", totalAuctionCoins, moduleAccCoins), ) return invariantMessage, broken } } // ValidAuctionInvariant verifies that all auctions in the store are independently valid func ValidAuctionInvariant(k Keeper) sdk.Invariant { return func(ctx sdk.Context) (string, bool) { var validationErr error var invalidAuction types.Auction k.IterateAuctions(ctx, func(auction types.Auction) bool { a, ok := auction.(types.GenesisAuction) if !ok { panic("stored auction type does not fulfill GenesisAuction interface") } currentTime := ctx.BlockTime() if !currentTime.Equal(time.Time{}) { // this avoids a simulator bug where app.InitGenesis is called with blockTime=0 instead of the correct time if a.GetEndTime().Before(currentTime) { validationErr = fmt.Errorf("endTime after current block time (%s)", currentTime) invalidAuction = a return true } } if err := a.Validate(); err != nil { validationErr = err invalidAuction = a return true } return false }) broken := validationErr != nil invariantMessage := sdk.FormatInvariant( types.ModuleName, "valid auctions", fmt.Sprintf( "\tfound invalid auction, reason: %s\n"+ "\tauction:\n\t%s\n", validationErr, invalidAuction), ) return invariantMessage, broken } } // ValidIndexInvariant checks that all auctions in the store are also in the index and vice versa. func ValidIndexInvariant(k Keeper) sdk.Invariant { return func(ctx sdk.Context) (string, bool) { /* Method: - check all the auction IDs in the index have a corresponding auction in the store - index is now valid but there could be extra auction in the store - check for these extra auctions by checking num items in the store equals that of index (store keys are always unique) - doesn't check the IDs in the auction structs match the IDs in the keys */ // Check all auction IDs in the index are in the auction store store := prefix.NewStore(ctx.KVStore(k.storeKey), types.AuctionKeyPrefix) indexIterator := sdk.KVStorePrefixIterator(ctx.KVStore(k.storeKey), types.AuctionByTimeKeyPrefix) defer indexIterator.Close() var indexLength int for ; indexIterator.Valid(); indexIterator.Next() { indexLength++ idBytes := indexIterator.Value() auctionBytes := store.Get(idBytes) if auctionBytes == nil { invariantMessage := sdk.FormatInvariant( types.ModuleName, "valid index", fmt.Sprintf("\tauction with ID '%d' found in index but not in store", types.Uint64FromBytes(idBytes))) return invariantMessage, true } } // Check length of auction store matches the length of the index storeIterator := sdk.KVStorePrefixIterator(ctx.KVStore(k.storeKey), types.AuctionKeyPrefix) defer storeIterator.Close() var storeLength int for ; storeIterator.Valid(); storeIterator.Next() { storeLength++ } if storeLength != indexLength { invariantMessage := sdk.FormatInvariant( types.ModuleName, "valid index", fmt.Sprintf("\tmismatched number of items in auction store (%d) and index (%d)", storeLength, indexLength)) return invariantMessage, true } return "", false } }