cosmos-sdk/x/ibc/client/query.go
colin axnér 7ea6b2c5e6
Update QueryTendermint to take in tendermint height (#7337)
* Update QueryTendermint to take in tendermint height

Update QueryTendermint to subtract the provided height by one to query at the IAVL height.

* Update x/ibc/client/query.go

Co-authored-by: Christopher Goes <cwgoes@pluranimity.org>

* update height check to > 2

Update height check to ensure that the client context height is greater than two before decrementing. Queries at height 0 and 1 are not expected to succeed. Documentation was updated to reflect this reasoning

* update query to return error for height <= 2

Co-authored-by: Federico Kunze <31522760+fedekunze@users.noreply.github.com>
Co-authored-by: Christopher Goes <cwgoes@pluranimity.org>
Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>
2020-09-24 06:53:30 +00:00

62 lines
2.1 KiB
Go

package client
import (
"fmt"
abci "github.com/tendermint/tendermint/abci/types"
"github.com/cosmos/cosmos-sdk/client"
"github.com/cosmos/cosmos-sdk/codec"
clienttypes "github.com/cosmos/cosmos-sdk/x/ibc/02-client/types"
commitmenttypes "github.com/cosmos/cosmos-sdk/x/ibc/23-commitment/types"
host "github.com/cosmos/cosmos-sdk/x/ibc/24-host"
)
// QueryTendermintProof performs an ABCI query with the given key and returns
// the value of the query, the proto encoded merkle proof, and the height of
// the Tendermint block containing the state root. The desired tendermint height
// to perform the query should be set in the client context. The query will be
// performed at one below this height (at the IAVL version) in order to obtain
// the correct merkle proof. Proof queries at height less than or equal to 2 are
// not supported.
// Issue: https://github.com/cosmos/cosmos-sdk/issues/6567
func QueryTendermintProof(clientCtx client.Context, key []byte) ([]byte, []byte, clienttypes.Height, error) {
height := clientCtx.Height
// ABCI queries at height less than or equal to 2 are not supported.
// Base app does not support queries for height less than or equal to 1.
// Therefore, a query at height 2 would be equivalent to a query at height 3
if clientCtx.Height <= 2 {
return nil, nil, clienttypes.Height{}, fmt.Errorf("proof queries at height <= 2 are not supported")
}
// Use the IAVL height if a valid tendermint height is passed in.
height--
req := abci.RequestQuery{
Path: fmt.Sprintf("store/%s/key", host.StoreKey),
Height: height,
Data: key,
Prove: true,
}
res, err := clientCtx.QueryABCI(req)
if err != nil {
return nil, nil, clienttypes.Height{}, err
}
merkleProof := commitmenttypes.MerkleProof{
Proof: res.ProofOps,
}
cdc := codec.NewProtoCodec(clientCtx.InterfaceRegistry)
proofBz, err := cdc.MarshalBinaryBare(&merkleProof)
if err != nil {
return nil, nil, clienttypes.Height{}, err
}
epoch := clienttypes.ParseChainID(clientCtx.ChainID)
return res.Value, proofBz, clienttypes.NewHeight(epoch, uint64(res.Height)+1), nil
}