refactor: rename IterateClients to IterateClientStates, add a prefix (#2856)

feat(api)!: rename `IterateClients` to `IterateClientStates`. The function now takes a prefix argument which may be used for prefix iteration over the client store.
feat: add `PrefixedClientStorePath` and `PrefixedClientStoreKey` functions to 24-host

Author: colin-axner

CHANGELOG.md

@@ -42,6 +42,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 ### API Breaking
 
+* (core/02-client) [\#2856](https://github.com/cosmos/ibc-go/pull/2856) Rename `IterateClients` to `IterateClientStates`. The function now takes a prefix argument which may be used for prefix iteration over the client store.
 * (apps/27-interchain-accounts) [\#2607](https://github.com/cosmos/ibc-go/pull/2607) `SerializeCosmosTx` now takes in a `[]proto.Message` instead of `[]sdk.Msg`.
 * (apps/transfer) [\#2446](https://github.com/cosmos/ibc-go/pull/2446) Remove `SendTransfer` function in favor of a private `sendTransfer` function. All IBC transfers must be initiated with `MsgTransfer`.
 * (apps/29-fee) [\#2395](https://github.com/cosmos/ibc-go/pull/2395) Remove param space from ics29 NewKeeper function. The field was unused.
@@ -115,6 +116,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 ### Features
 
+* (core/24-host) [\#2856](https://github.com/cosmos/ibc-go/pull/2856) Add `PrefixedClientStorePath` and `PrefixedClientStoreKey` functions to 24-host
 * (core/02-client) [\#2819](https://github.com/cosmos/ibc-go/pull/2819) Add automatic in-place store migrations to remove the localhost client and migrate existing solo machine definitions.
 * (light-clients/06-solomachine) [\#2826](https://github.com/cosmos/ibc-go/pull/2826) Add `AppModuleBasic` for the 06-solomachine client and remove solo machine type registration from core IBC. Chains must register the `AppModuleBasic` of light clients. 
 * (light-clients/07-tendermint) [\#2825](https://github.com/cosmos/ibc-go/pull/2825) Add `AppModuleBasic` for the 07-tendermint client and remove tendermint type registration from core IBC. Chains must register the `AppModuleBasic` of light clients. 

modules/core/02-client/keeper/keeper.go

@@ -147,7 +147,7 @@ func (k Keeper) IterateConsensusStates(ctx sdk.Context, cb func(clientID string,
 // GetAllGenesisClients returns all the clients in state with their client ids returned as IdentifiedClientState
 func (k Keeper) GetAllGenesisClients(ctx sdk.Context) types.IdentifiedClientStates {
 	var genClients types.IdentifiedClientStates
-	k.IterateClients(ctx, func(clientID string, cs exported.ClientState) bool {
+	k.IterateClientStates(ctx, nil, func(clientID string, cs exported.ClientState) bool {
 		genClients = append(genClients, types.NewIdentifiedClientState(clientID, cs))
 		return false
 	})
@@ -350,12 +350,12 @@ func (k Keeper) SetUpgradedConsensusState(ctx sdk.Context, planHeight int64, bz
 	return k.upgradeKeeper.SetUpgradedConsensusState(ctx, planHeight, bz)
 }
 
-// IterateClients provides an iterator over all stored light client State
+// IterateClientStates provides an iterator over all stored light client State
 // objects. For each State object, cb will be called. If the cb returns true,
 // the iterator will close and stop.
-func (k Keeper) IterateClients(ctx sdk.Context, cb func(clientID string, cs exported.ClientState) bool) {
+func (k Keeper) IterateClientStates(ctx sdk.Context, prefix []byte, cb func(clientID string, cs exported.ClientState) bool) {
 	store := ctx.KVStore(k.storeKey)
-	iterator := sdk.KVStorePrefixIterator(store, host.KeyClientStorePrefix)
+	iterator := sdk.KVStorePrefixIterator(store, host.PrefixedClientStoreKey(prefix))
 
 	defer iterator.Close()
 	for ; iterator.Valid(); iterator.Next() {
@@ -375,11 +375,13 @@ func (k Keeper) IterateClients(ctx sdk.Context, cb func(clientID string, cs expo
 }
 
 // GetAllClients returns all stored light client State objects.
-func (k Keeper) GetAllClients(ctx sdk.Context) (states []exported.ClientState) {
-	k.IterateClients(ctx, func(_ string, state exported.ClientState) bool {
+func (k Keeper) GetAllClients(ctx sdk.Context) []exported.ClientState {
+	var states []exported.ClientState
+	k.IterateClientStates(ctx, nil, func(_ string, state exported.ClientState) bool {
 		states = append(states, state)
 		return false
 	})
+
 	return states
 }
 

modules/core/02-client/keeper/keeper_test.go

@@ -386,3 +386,67 @@ func (suite KeeperTestSuite) TestGetAllConsensusStates() {
 	consStates := suite.chainA.App.GetIBCKeeper().ClientKeeper.GetAllConsensusStates(suite.chainA.GetContext())
 	suite.Require().Equal(expConsensusStates, consStates, "%s \n\n%s", expConsensusStates, consStates)
 }
+
+func (suite KeeperTestSuite) TestIterateClientStates() {
+	paths := []*ibctesting.Path{
+		ibctesting.NewPath(suite.chainA, suite.chainB),
+		ibctesting.NewPath(suite.chainA, suite.chainB),
+		ibctesting.NewPath(suite.chainA, suite.chainB),
+	}
+
+	solomachines := []*ibctesting.Solomachine{
+		ibctesting.NewSolomachine(suite.T(), suite.chainA.Codec, "06-solomachine-0", "testing", 1),
+		ibctesting.NewSolomachine(suite.T(), suite.chainA.Codec, "06-solomachine-1", "testing", 4),
+	}
+
+	var (
+		expTMClientIDs = make([]string, len(paths))
+		expSMClientIDs = make([]string, len(solomachines))
+	)
+
+	// create tendermint clients
+	for i, path := range paths {
+		suite.coordinator.SetupClients(path)
+		expTMClientIDs[i] = path.EndpointA.ClientID
+	}
+
+	// create solomachine clients
+	for i, sm := range solomachines {
+		expSMClientIDs[i] = sm.CreateClient(suite.chainA)
+	}
+
+	testCases := []struct {
+		name         string
+		prefix       []byte
+		expClientIDs []string
+	}{
+		{
+			"all clientIDs",
+			nil,
+			append(expSMClientIDs, expTMClientIDs...),
+		},
+		{
+			"tendermint clientIDs",
+			[]byte(exported.Tendermint),
+			expTMClientIDs,
+		},
+		{
+			"solo machine clientIDs",
+			[]byte(exported.Solomachine),
+			expSMClientIDs,
+		},
+	}
+
+	for _, tc := range testCases {
+		tc := tc
+		suite.Run(tc.name, func() {
+			var clientIDs []string
+			suite.chainA.GetSimApp().IBCKeeper.ClientKeeper.IterateClientStates(suite.chainA.GetContext(), tc.prefix, func(clientID string, _ exported.ClientState) bool {
+				clientIDs = append(clientIDs, clientID)
+				return false
+			})
+
+			suite.Require().Equal(tc.expClientIDs, clientIDs)
+		})
+	}
+}

modules/core/03-connection/keeper/keeper.go

@@ -146,7 +146,7 @@ func (k Keeper) SetNextConnectionSequence(ctx sdk.Context, sequence uint64) {
 // no paths are stored.
 func (k Keeper) GetAllClientConnectionPaths(ctx sdk.Context) []types.ConnectionPaths {
 	var allConnectionPaths []types.ConnectionPaths
-	k.clientKeeper.IterateClients(ctx, func(clientID string, cs exported.ClientState) bool {
+	k.clientKeeper.IterateClientStates(ctx, nil, func(clientID string, cs exported.ClientState) bool {
 		paths, found := k.GetClientConnectionPaths(ctx, clientID)
 		if !found {
 			// continue when connection handshake is not initialized

modules/core/03-connection/types/expected_keepers.go

@@ -12,6 +12,6 @@ type ClientKeeper interface {
 	GetClientConsensusState(ctx sdk.Context, clientID string, height exported.Height) (exported.ConsensusState, bool)
 	GetSelfConsensusState(ctx sdk.Context, height exported.Height) (exported.ConsensusState, error)
 	ValidateSelfClient(ctx sdk.Context, clientState exported.ClientState) error
-	IterateClients(ctx sdk.Context, cb func(string, exported.ClientState) bool)
+	IterateClientStates(ctx sdk.Context, prefix []byte, cb func(string, exported.ClientState) bool)
 	ClientStore(ctx sdk.Context, clientID string) sdk.KVStore
 }

modules/core/24-host/keys.go

@@ -55,6 +55,20 @@ func FullClientKey(clientID string, path []byte) []byte {
 	return []byte(FullClientPath(clientID, string(path)))
 }
 
+// PrefixedClientStorePath returns a key path which can be used for prefixed
+// key store iteration. The prefix may be a clientType, clientID, or any
+// valid key prefix which may be concatenated with the client store constant.
+func PrefixedClientStorePath(prefix []byte) string {
+	return fmt.Sprintf("%s/%s", KeyClientStorePrefix, prefix)
+}
+
+// PrefixedClientStoreKey returns a key which can be used for prefixed
+// key store iteration. The prefix may be a clientType, clientID, or any
+// valid key prefix which may be concatenated with the client store constant.
+func PrefixedClientStoreKey(prefix []byte) []byte {
+	return []byte(PrefixedClientStorePath(prefix))
+}
+
 // ICS02
 // The following paths are the keys to the store as defined in https://github.com/cosmos/ibc/tree/master/spec/core/ics-002-client-semantics#path-space