From 73721253a0f5ba141d5d0d5ff4aded8c98fd9241 Mon Sep 17 00:00:00 2001
From: chatton <github.qpeyb@simplelogin.fr>
Date: Mon, 20 Nov 2023 13:11:21 +0000
Subject: [PATCH 01/13] chore: adding controller implementation for
 OnChanUpgradeInit

---
 .../controller/ibc_middleware.go              | 49 ++++++++++++++++++-
 .../controller/keeper/keeper.go               | 14 ++++++
 .../27-interchain-accounts/types/metadata.go  |  9 ++++
 3 files changed, 70 insertions(+), 2 deletions(-)

diff --git a/modules/apps/27-interchain-accounts/controller/ibc_middleware.go b/modules/apps/27-interchain-accounts/controller/ibc_middleware.go
index 8c004012694..c64bf998246 100644
--- a/modules/apps/27-interchain-accounts/controller/ibc_middleware.go
+++ b/modules/apps/27-interchain-accounts/controller/ibc_middleware.go
@@ -232,8 +232,53 @@ func (im IBCMiddleware) OnTimeoutPacket(
 }
 
 // OnChanUpgradeInit implements the IBCModule interface
-func (IBCMiddleware) OnChanUpgradeInit(ctx sdk.Context, portID, channelID string, order channeltypes.Order, connectionHops []string, version string) (string, error) {
-	return icatypes.Version, nil
+func (im IBCMiddleware) OnChanUpgradeInit(ctx sdk.Context, portID, channelID string, order channeltypes.Order, connectionHops []string, version string) (string, error) {
+	if version == "" {
+		return "", errorsmod.Wrap(icatypes.ErrInvalidChannelFlow, "version cannot be empty")
+	}
+
+	metadata, err := icatypes.ParseMedataFromString(version)
+	if err != nil {
+		return "", err
+	}
+
+	channel, err := im.keeper.GetChannel(ctx, portID, channelID)
+	if err != nil {
+		return "", err
+	}
+
+	currentMetadata, err := icatypes.ParseMedataFromString(channel.Version)
+	if err != nil {
+		return "", err
+	}
+
+	if err := icatypes.ValidateControllerMetadata(ctx, im.keeper.GetChannelKeeper(), connectionHops, metadata); err != nil {
+		return "", errorsmod.Wrap(err, "invalid metadata")
+	}
+
+	// the interchain account address on the host chain
+	// must remain the same after the upgrade.
+	if currentMetadata.Address != metadata.Address {
+		return "", errorsmod.Wrap(icatypes.ErrInvalidChannelFlow, "address cannot be changed")
+	}
+
+	// at the moment it is not supported to perform upgrades that
+	// change the connection ID of the controller or host chains.
+	// therefore these connection IDs much remain the same as before.
+	if currentMetadata.ControllerConnectionId != metadata.ControllerConnectionId {
+		return "", errorsmod.Wrap(icatypes.ErrInvalidChannelFlow, "controller connection ID cannot be changed")
+	}
+
+	if currentMetadata.HostConnectionId != metadata.HostConnectionId {
+		return "", errorsmod.Wrap(icatypes.ErrInvalidChannelFlow, "host connection ID cannot be changed")
+	}
+
+	if currentMetadata.ControllerConnectionId != connectionHops[0] {
+		return "", errorsmod.Wrap(icatypes.ErrInvalidChannelFlow, "proposed connection hop must not change")
+	}
+
+	metadataBz := icatypes.ModuleCdc.MustMarshalJSON(&metadata)
+	return string(metadataBz), nil
 }
 
 // OnChanUpgradeTry implements the IBCModule interface
diff --git a/modules/apps/27-interchain-accounts/controller/keeper/keeper.go b/modules/apps/27-interchain-accounts/controller/keeper/keeper.go
index 63e606c395e..6a55887db78 100644
--- a/modules/apps/27-interchain-accounts/controller/keeper/keeper.go
+++ b/modules/apps/27-interchain-accounts/controller/keeper/keeper.go
@@ -85,6 +85,11 @@ func (k Keeper) GetConnectionID(ctx sdk.Context, portID, channelID string) (stri
 	return channel.ConnectionHops[0], nil
 }
 
+// GetChannelKeeper returns the ChannelKeeper
+func (k Keeper) GetChannelKeeper() icatypes.ChannelKeeper {
+	return k.channelKeeper
+}
+
 // GetAllPorts returns all ports to which the interchain accounts controller module is bound. Used in ExportGenesis
 func (k Keeper) GetAllPorts(ctx sdk.Context) []string {
 	store := ctx.KVStore(k.storeKey)
@@ -156,6 +161,15 @@ func (k Keeper) GetOpenActiveChannel(ctx sdk.Context, connectionID, portID strin
 	return "", false
 }
 
+// GetChannel returns the channel associated with the provided portID and channelID.
+func (k Keeper) GetChannel(ctx sdk.Context, portID, channelID string) (channeltypes.Channel, error) {
+	channel, found := k.channelKeeper.GetChannel(ctx, portID, channelID)
+	if !found {
+		return channeltypes.Channel{}, errorsmod.Wrapf(channeltypes.ErrChannelNotFound, "port ID (%s) channel ID (%s)", portID, channelID)
+	}
+	return channel, nil
+}
+
 // IsActiveChannelClosed retrieves the active channel from the store and returns true if the channel state is CLOSED, otherwise false
 func (k Keeper) IsActiveChannelClosed(ctx sdk.Context, connectionID, portID string) bool {
 	channelID, found := k.GetActiveChannelID(ctx, connectionID, portID)
diff --git a/modules/apps/27-interchain-accounts/types/metadata.go b/modules/apps/27-interchain-accounts/types/metadata.go
index 29d1da45d42..03e559e8e7d 100644
--- a/modules/apps/27-interchain-accounts/types/metadata.go
+++ b/modules/apps/27-interchain-accounts/types/metadata.go
@@ -54,6 +54,15 @@ func NewDefaultMetadataString(controllerConnectionID, hostConnectionID string) s
 	return string(ModuleCdc.MustMarshalJSON(&metadata))
 }
 
+// ParseMedataFromString parses Metadata from a json encoded version string.
+func ParseMedataFromString(versionString string) (Metadata, error) {
+	var metadata Metadata
+	if err := ModuleCdc.UnmarshalJSON([]byte(versionString), &metadata); err != nil {
+		return Metadata{}, errorsmod.Wrapf(ErrUnknownDataType, "cannot unmarshal ICS-27 interchain accounts metadata")
+	}
+	return metadata, nil
+}
+
 // IsPreviousMetadataEqual compares a metadata to a previous version string set in a channel struct.
 // It ensures all fields are equal except the Address string
 func IsPreviousMetadataEqual(previousVersion string, metadata Metadata) bool {

From 4427f1df245bda8e2de48080c437aa9ccb3f967d Mon Sep 17 00:00:00 2001
From: chatton <github.qpeyb@simplelogin.fr>
Date: Mon, 20 Nov 2023 14:21:24 +0000
Subject: [PATCH 02/13] chore: happy path test passing

---
 .../controller/keeper/handshake_test.go       | 55 +++++++++++++++++++
 1 file changed, 55 insertions(+)

diff --git a/modules/apps/27-interchain-accounts/controller/keeper/handshake_test.go b/modules/apps/27-interchain-accounts/controller/keeper/handshake_test.go
index 29ebf75dec1..e22143df4fc 100644
--- a/modules/apps/27-interchain-accounts/controller/keeper/handshake_test.go
+++ b/modules/apps/27-interchain-accounts/controller/keeper/handshake_test.go
@@ -471,3 +471,58 @@ func (suite *KeeperTestSuite) TestOnChanCloseConfirm() {
 		})
 	}
 }
+
+func (suite *KeeperTestSuite) TestOnChanUpgradeInit() {
+	var path *ibctesting.Path
+
+	testCases := []struct {
+		name     string
+		malleate func()
+		expError error
+	}{
+		{
+			"success", func() {}, nil,
+		},
+	}
+
+	for _, tc := range testCases {
+		tc := tc
+
+		suite.Run(tc.name, func() {
+			suite.SetupTest() // reset
+
+			path = NewICAPath(suite.chainA, suite.chainB)
+			suite.coordinator.SetupConnections(path)
+
+			err := SetupICAPath(path, TestOwnerAddress)
+			suite.Require().NoError(err)
+
+			channel := path.EndpointA.GetChannel()
+
+			currentMetadata, err := icatypes.ParseMedataFromString(channel.Version)
+			suite.Require().NoError(err)
+
+			metadata := icatypes.NewDefaultMetadata(path.EndpointA.ConnectionID, path.EndpointB.ConnectionID)
+			// use the same address as the previous metadata.
+			metadata.Address = currentMetadata.Address
+
+			// this is the actual change to the version.
+			metadata.Encoding = icatypes.EncodingProto3JSON
+
+			path.EndpointA.ChannelConfig.ProposedUpgrade.Fields.Version = string(icatypes.ModuleCdc.MustMarshalJSON(&metadata))
+			path.EndpointB.ChannelConfig.ProposedUpgrade.Fields.Version = string(icatypes.ModuleCdc.MustMarshalJSON(&metadata))
+
+			tc.malleate() // malleate mutates test data
+
+			err = path.EndpointA.ChanUpgradeInit()
+
+			expPass := tc.expError == nil
+
+			if expPass {
+				suite.Require().NoError(err)
+			} else {
+				suite.Require().Equal(tc.expError, err)
+			}
+		})
+	}
+}

From 978a7a2ec1654e6d32a893ff81d7e5f87d5e7d88 Mon Sep 17 00:00:00 2001
From: chatton <github.qpeyb@simplelogin.fr>
Date: Mon, 20 Nov 2023 16:25:32 +0000
Subject: [PATCH 03/13] chore: adding fail case

---
 .../controller/keeper/handshake_test.go       | 32 +++++++++++++++----
 1 file changed, 26 insertions(+), 6 deletions(-)

diff --git a/modules/apps/27-interchain-accounts/controller/keeper/handshake_test.go b/modules/apps/27-interchain-accounts/controller/keeper/handshake_test.go
index e22143df4fc..6a3560ab1b5 100644
--- a/modules/apps/27-interchain-accounts/controller/keeper/handshake_test.go
+++ b/modules/apps/27-interchain-accounts/controller/keeper/handshake_test.go
@@ -473,7 +473,10 @@ func (suite *KeeperTestSuite) TestOnChanCloseConfirm() {
 }
 
 func (suite *KeeperTestSuite) TestOnChanUpgradeInit() {
-	var path *ibctesting.Path
+	var (
+		path     *ibctesting.Path
+		metadata icatypes.Metadata
+	)
 
 	testCases := []struct {
 		name     string
@@ -481,7 +484,24 @@ func (suite *KeeperTestSuite) TestOnChanUpgradeInit() {
 		expError error
 	}{
 		{
-			"success", func() {}, nil,
+			"success",
+			func() {},
+			nil,
+		},
+		{
+			"failure: no changes made in upgrade",
+			func() {
+				// revert the change so that proposed metadata is the same as current.
+				metadata.Encoding = icatypes.EncodingProtobuf
+			},
+			channeltypes.ErrChannelExists,
+		},
+		{
+			name: "failure: invalid metadata",
+			malleate: func() {
+
+			},
+			expError: nil,
 		},
 	}
 
@@ -502,18 +522,18 @@ func (suite *KeeperTestSuite) TestOnChanUpgradeInit() {
 			currentMetadata, err := icatypes.ParseMedataFromString(channel.Version)
 			suite.Require().NoError(err)
 
-			metadata := icatypes.NewDefaultMetadata(path.EndpointA.ConnectionID, path.EndpointB.ConnectionID)
+			metadata = icatypes.NewDefaultMetadata(path.EndpointA.ConnectionID, path.EndpointB.ConnectionID)
 			// use the same address as the previous metadata.
 			metadata.Address = currentMetadata.Address
 
 			// this is the actual change to the version.
 			metadata.Encoding = icatypes.EncodingProto3JSON
 
+			tc.malleate() // malleate mutates test data
+
 			path.EndpointA.ChannelConfig.ProposedUpgrade.Fields.Version = string(icatypes.ModuleCdc.MustMarshalJSON(&metadata))
 			path.EndpointB.ChannelConfig.ProposedUpgrade.Fields.Version = string(icatypes.ModuleCdc.MustMarshalJSON(&metadata))
 
-			tc.malleate() // malleate mutates test data
-
 			err = path.EndpointA.ChanUpgradeInit()
 
 			expPass := tc.expError == nil
@@ -521,7 +541,7 @@ func (suite *KeeperTestSuite) TestOnChanUpgradeInit() {
 			if expPass {
 				suite.Require().NoError(err)
 			} else {
-				suite.Require().Equal(tc.expError, err)
+				suite.Require().Contains(err.Error(), tc.expError.Error())
 			}
 		})
 	}

From 925392f1036856ab3ca5a284ad94e8c819b2c331 Mon Sep 17 00:00:00 2001
From: chatton <github.qpeyb@simplelogin.fr>
Date: Tue, 21 Nov 2023 09:38:57 +0000
Subject: [PATCH 04/13] chore: adding additional test cases

---
 .../controller/ibc_middleware.go              | 14 ++-------
 .../controller/keeper/handshake_test.go       | 29 +++++++++++++++++--
 2 files changed, 29 insertions(+), 14 deletions(-)

diff --git a/modules/apps/27-interchain-accounts/controller/ibc_middleware.go b/modules/apps/27-interchain-accounts/controller/ibc_middleware.go
index c64bf998246..ff0f7985202 100644
--- a/modules/apps/27-interchain-accounts/controller/ibc_middleware.go
+++ b/modules/apps/27-interchain-accounts/controller/ibc_middleware.go
@@ -2,6 +2,7 @@ package controller
 
 import (
 	"errors"
+	"strings"
 
 	errorsmod "cosmossdk.io/errors"
 
@@ -233,7 +234,7 @@ func (im IBCMiddleware) OnTimeoutPacket(
 
 // OnChanUpgradeInit implements the IBCModule interface
 func (im IBCMiddleware) OnChanUpgradeInit(ctx sdk.Context, portID, channelID string, order channeltypes.Order, connectionHops []string, version string) (string, error) {
-	if version == "" {
+	if strings.TrimSpace(version) == "" {
 		return "", errorsmod.Wrap(icatypes.ErrInvalidChannelFlow, "version cannot be empty")
 	}
 
@@ -262,17 +263,6 @@ func (im IBCMiddleware) OnChanUpgradeInit(ctx sdk.Context, portID, channelID str
 		return "", errorsmod.Wrap(icatypes.ErrInvalidChannelFlow, "address cannot be changed")
 	}
 
-	// at the moment it is not supported to perform upgrades that
-	// change the connection ID of the controller or host chains.
-	// therefore these connection IDs much remain the same as before.
-	if currentMetadata.ControllerConnectionId != metadata.ControllerConnectionId {
-		return "", errorsmod.Wrap(icatypes.ErrInvalidChannelFlow, "controller connection ID cannot be changed")
-	}
-
-	if currentMetadata.HostConnectionId != metadata.HostConnectionId {
-		return "", errorsmod.Wrap(icatypes.ErrInvalidChannelFlow, "host connection ID cannot be changed")
-	}
-
 	if currentMetadata.ControllerConnectionId != connectionHops[0] {
 		return "", errorsmod.Wrap(icatypes.ErrInvalidChannelFlow, "proposed connection hop must not change")
 	}
diff --git a/modules/apps/27-interchain-accounts/controller/keeper/handshake_test.go b/modules/apps/27-interchain-accounts/controller/keeper/handshake_test.go
index 6a3560ab1b5..42d8e5cac01 100644
--- a/modules/apps/27-interchain-accounts/controller/keeper/handshake_test.go
+++ b/modules/apps/27-interchain-accounts/controller/keeper/handshake_test.go
@@ -3,6 +3,7 @@ package keeper_test
 import (
 	capabilitytypes "github.com/cosmos/ibc-go/modules/capability/types"
 	icatypes "github.com/cosmos/ibc-go/v8/modules/apps/27-interchain-accounts/types"
+	connectiontypes "github.com/cosmos/ibc-go/v8/modules/core/03-connection/types"
 	channeltypes "github.com/cosmos/ibc-go/v8/modules/core/04-channel/types"
 	host "github.com/cosmos/ibc-go/v8/modules/core/24-host"
 	ibctesting "github.com/cosmos/ibc-go/v8/testing"
@@ -499,9 +500,32 @@ func (suite *KeeperTestSuite) TestOnChanUpgradeInit() {
 		{
 			name: "failure: invalid metadata",
 			malleate: func() {
-
+				metadata.Address = TestOwnerAddress
+			},
+			expError: icatypes.ErrInvalidChannelFlow,
+		},
+		{
+			name: "failure: change connection id",
+			malleate: func() {
+				metadata.ControllerConnectionId = "connection-100"
 			},
-			expError: nil,
+			expError: connectiontypes.ErrInvalidConnection,
+		},
+		{
+			name: "failure: change host connection id",
+			malleate: func() {
+				metadata.HostConnectionId = "connection-100"
+			},
+			expError: connectiontypes.ErrInvalidConnection,
+		},
+		{
+			name: "failure: invalid metadata string",
+			malleate: func() {
+				channel := path.EndpointA.GetChannel()
+				channel.Version = "invalid-metadata-string"
+				path.EndpointA.SetChannel(channel)
+			},
+			expError: icatypes.ErrUnknownDataType,
 		},
 	}
 
@@ -541,6 +565,7 @@ func (suite *KeeperTestSuite) TestOnChanUpgradeInit() {
 			if expPass {
 				suite.Require().NoError(err)
 			} else {
+				suite.Require().Error(err)
 				suite.Require().Contains(err.Error(), tc.expError.Error())
 			}
 		})

From fa5e34989b4a9e13c4f3b7769b159566981eb513 Mon Sep 17 00:00:00 2001
From: chatton <github.qpeyb@simplelogin.fr>
Date: Tue, 21 Nov 2023 10:08:03 +0000
Subject: [PATCH 05/13] chore: fix linting

---
 .../controller/keeper/handshake_test.go                   | 8 ++++++--
 modules/capability/module.go                              | 2 +-
 scripts/go-lint-all.sh                                    | 4 ++--
 3 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/modules/apps/27-interchain-accounts/controller/keeper/handshake_test.go b/modules/apps/27-interchain-accounts/controller/keeper/handshake_test.go
index 42d8e5cac01..5a6b2e2ef60 100644
--- a/modules/apps/27-interchain-accounts/controller/keeper/handshake_test.go
+++ b/modules/apps/27-interchain-accounts/controller/keeper/handshake_test.go
@@ -9,6 +9,10 @@ import (
 	ibctesting "github.com/cosmos/ibc-go/v8/testing"
 )
 
+const (
+	differentConnectionID = "connection-100"
+)
+
 func (suite *KeeperTestSuite) TestOnChanOpenInit() {
 	var (
 		channel  *channeltypes.Channel
@@ -507,14 +511,14 @@ func (suite *KeeperTestSuite) TestOnChanUpgradeInit() {
 		{
 			name: "failure: change connection id",
 			malleate: func() {
-				metadata.ControllerConnectionId = "connection-100"
+				metadata.ControllerConnectionId = differentConnectionID
 			},
 			expError: connectiontypes.ErrInvalidConnection,
 		},
 		{
 			name: "failure: change host connection id",
 			malleate: func() {
-				metadata.HostConnectionId = "connection-100"
+				metadata.HostConnectionId = differentConnectionID
 			},
 			expError: connectiontypes.ErrInvalidConnection,
 		},
diff --git a/modules/capability/module.go b/modules/capability/module.go
index 786e41cf6e8..5f048a3b838 100644
--- a/modules/capability/module.go
+++ b/modules/capability/module.go
@@ -47,7 +47,7 @@ func NewAppModuleBasic(cdc codec.Codec) AppModuleBasic {
 }
 
 // Name returns the capability module's name.
-func (am AppModuleBasic) Name() string {
+func (AppModuleBasic) Name() string {
 	return types.ModuleName
 }
 
diff --git a/scripts/go-lint-all.sh b/scripts/go-lint-all.sh
index 7a7883b36aa..a6811de23b7 100755
--- a/scripts/go-lint-all.sh
+++ b/scripts/go-lint-all.sh
@@ -9,10 +9,10 @@ lint_module() {
   local root="$1"
   shift
   cd "$(dirname "$root")" &&
-    echo "linting $(grep "^module" go.mod) [$(date -Iseconds -u)]" &&
+    echo "linting $(grep "^module" go.mod) [$(date -u +"%Y-%m-%dT%H:%M:%S")]" &&
     golangci-lint run ./... -c "${REPO_ROOT}/.golangci.yml" "$@"
 }
 export -f lint_module
 
 find "${REPO_ROOT}" -type f -name go.mod -print0 |
-  xargs -0 -I{} bash -c 'lint_module "$@"' _ {} "$@"
\ No newline at end of file
+  xargs -0 -I{} bash -c 'lint_module "$@"' _ {} "$@"

From 32dba02e746e70457240192ac76770e9be78a147 Mon Sep 17 00:00:00 2001
From: chatton <github.qpeyb@simplelogin.fr>
Date: Tue, 21 Nov 2023 10:25:38 +0000
Subject: [PATCH 06/13] chore: improving errors

---
 .../27-interchain-accounts/controller/ibc_middleware.go    | 7 ++++---
 .../controller/keeper/handshake_test.go                    | 2 +-
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/modules/apps/27-interchain-accounts/controller/ibc_middleware.go b/modules/apps/27-interchain-accounts/controller/ibc_middleware.go
index ff0f7985202..0efbf0e909f 100644
--- a/modules/apps/27-interchain-accounts/controller/ibc_middleware.go
+++ b/modules/apps/27-interchain-accounts/controller/ibc_middleware.go
@@ -13,6 +13,7 @@ import (
 	"github.com/cosmos/ibc-go/v8/modules/apps/27-interchain-accounts/controller/types"
 	icatypes "github.com/cosmos/ibc-go/v8/modules/apps/27-interchain-accounts/types"
 	clienttypes "github.com/cosmos/ibc-go/v8/modules/core/02-client/types"
+	connectiontypes "github.com/cosmos/ibc-go/v8/modules/core/03-connection/types"
 	channeltypes "github.com/cosmos/ibc-go/v8/modules/core/04-channel/types"
 	porttypes "github.com/cosmos/ibc-go/v8/modules/core/05-port/types"
 	host "github.com/cosmos/ibc-go/v8/modules/core/24-host"
@@ -235,7 +236,7 @@ func (im IBCMiddleware) OnTimeoutPacket(
 // OnChanUpgradeInit implements the IBCModule interface
 func (im IBCMiddleware) OnChanUpgradeInit(ctx sdk.Context, portID, channelID string, order channeltypes.Order, connectionHops []string, version string) (string, error) {
 	if strings.TrimSpace(version) == "" {
-		return "", errorsmod.Wrap(icatypes.ErrInvalidChannelFlow, "version cannot be empty")
+		return "", errorsmod.Wrap(icatypes.ErrInvalidVersion, "version cannot be empty")
 	}
 
 	metadata, err := icatypes.ParseMedataFromString(version)
@@ -260,11 +261,11 @@ func (im IBCMiddleware) OnChanUpgradeInit(ctx sdk.Context, portID, channelID str
 	// the interchain account address on the host chain
 	// must remain the same after the upgrade.
 	if currentMetadata.Address != metadata.Address {
-		return "", errorsmod.Wrap(icatypes.ErrInvalidChannelFlow, "address cannot be changed")
+		return "", errorsmod.Wrap(icatypes.ErrInvalidAccountAddress, "address cannot be changed")
 	}
 
 	if currentMetadata.ControllerConnectionId != connectionHops[0] {
-		return "", errorsmod.Wrap(icatypes.ErrInvalidChannelFlow, "proposed connection hop must not change")
+		return "", errorsmod.Wrap(connectiontypes.ErrInvalidConnectionIdentifier, "proposed connection hop must not change")
 	}
 
 	metadataBz := icatypes.ModuleCdc.MustMarshalJSON(&metadata)
diff --git a/modules/apps/27-interchain-accounts/controller/keeper/handshake_test.go b/modules/apps/27-interchain-accounts/controller/keeper/handshake_test.go
index 5a6b2e2ef60..827c37ed74e 100644
--- a/modules/apps/27-interchain-accounts/controller/keeper/handshake_test.go
+++ b/modules/apps/27-interchain-accounts/controller/keeper/handshake_test.go
@@ -506,7 +506,7 @@ func (suite *KeeperTestSuite) TestOnChanUpgradeInit() {
 			malleate: func() {
 				metadata.Address = TestOwnerAddress
 			},
-			expError: icatypes.ErrInvalidChannelFlow,
+			expError: icatypes.ErrInvalidAccountAddress,
 		},
 		{
 			name: "failure: change connection id",

From 292529e9e8441d8139013055c2899bab366b43ad Mon Sep 17 00:00:00 2001
From: chatton <github.qpeyb@simplelogin.fr>
Date: Tue, 21 Nov 2023 11:34:56 +0000
Subject: [PATCH 07/13] chore: refactor to use test keeper function directly

---
 .../controller/ibc_middleware.go              | 38 +-----------------
 .../controller/keeper/handshake.go            | 40 +++++++++++++++++++
 .../controller/keeper/handshake_test.go       | 30 ++++++++------
 .../controller/keeper/keeper.go               | 14 -------
 4 files changed, 58 insertions(+), 64 deletions(-)

diff --git a/modules/apps/27-interchain-accounts/controller/ibc_middleware.go b/modules/apps/27-interchain-accounts/controller/ibc_middleware.go
index 0efbf0e909f..6fb9a7a357d 100644
--- a/modules/apps/27-interchain-accounts/controller/ibc_middleware.go
+++ b/modules/apps/27-interchain-accounts/controller/ibc_middleware.go
@@ -2,7 +2,6 @@ package controller
 
 import (
 	"errors"
-	"strings"
 
 	errorsmod "cosmossdk.io/errors"
 
@@ -13,7 +12,6 @@ import (
 	"github.com/cosmos/ibc-go/v8/modules/apps/27-interchain-accounts/controller/types"
 	icatypes "github.com/cosmos/ibc-go/v8/modules/apps/27-interchain-accounts/types"
 	clienttypes "github.com/cosmos/ibc-go/v8/modules/core/02-client/types"
-	connectiontypes "github.com/cosmos/ibc-go/v8/modules/core/03-connection/types"
 	channeltypes "github.com/cosmos/ibc-go/v8/modules/core/04-channel/types"
 	porttypes "github.com/cosmos/ibc-go/v8/modules/core/05-port/types"
 	host "github.com/cosmos/ibc-go/v8/modules/core/24-host"
@@ -235,41 +233,7 @@ func (im IBCMiddleware) OnTimeoutPacket(
 
 // OnChanUpgradeInit implements the IBCModule interface
 func (im IBCMiddleware) OnChanUpgradeInit(ctx sdk.Context, portID, channelID string, order channeltypes.Order, connectionHops []string, version string) (string, error) {
-	if strings.TrimSpace(version) == "" {
-		return "", errorsmod.Wrap(icatypes.ErrInvalidVersion, "version cannot be empty")
-	}
-
-	metadata, err := icatypes.ParseMedataFromString(version)
-	if err != nil {
-		return "", err
-	}
-
-	channel, err := im.keeper.GetChannel(ctx, portID, channelID)
-	if err != nil {
-		return "", err
-	}
-
-	currentMetadata, err := icatypes.ParseMedataFromString(channel.Version)
-	if err != nil {
-		return "", err
-	}
-
-	if err := icatypes.ValidateControllerMetadata(ctx, im.keeper.GetChannelKeeper(), connectionHops, metadata); err != nil {
-		return "", errorsmod.Wrap(err, "invalid metadata")
-	}
-
-	// the interchain account address on the host chain
-	// must remain the same after the upgrade.
-	if currentMetadata.Address != metadata.Address {
-		return "", errorsmod.Wrap(icatypes.ErrInvalidAccountAddress, "address cannot be changed")
-	}
-
-	if currentMetadata.ControllerConnectionId != connectionHops[0] {
-		return "", errorsmod.Wrap(connectiontypes.ErrInvalidConnectionIdentifier, "proposed connection hop must not change")
-	}
-
-	metadataBz := icatypes.ModuleCdc.MustMarshalJSON(&metadata)
-	return string(metadataBz), nil
+	return im.keeper.OnChanUpgradeInit(ctx, portID, channelID, connectionHops, version)
 }
 
 // OnChanUpgradeTry implements the IBCModule interface
diff --git a/modules/apps/27-interchain-accounts/controller/keeper/handshake.go b/modules/apps/27-interchain-accounts/controller/keeper/handshake.go
index 0ce3802b48e..a15fb35f4cf 100644
--- a/modules/apps/27-interchain-accounts/controller/keeper/handshake.go
+++ b/modules/apps/27-interchain-accounts/controller/keeper/handshake.go
@@ -10,6 +10,7 @@ import (
 
 	capabilitytypes "github.com/cosmos/ibc-go/modules/capability/types"
 	icatypes "github.com/cosmos/ibc-go/v8/modules/apps/27-interchain-accounts/types"
+	connectiontypes "github.com/cosmos/ibc-go/v8/modules/core/03-connection/types"
 	channeltypes "github.com/cosmos/ibc-go/v8/modules/core/04-channel/types"
 )
 
@@ -136,3 +137,42 @@ func (Keeper) OnChanCloseConfirm(
 ) error {
 	return nil
 }
+
+// OnChanUpgradeInit performs the upgrade init step of the channel upgrade handshake.
+func (k Keeper) OnChanUpgradeInit(ctx sdk.Context, portID, channelID string, connectionHops []string, version string) (string, error) {
+	if strings.TrimSpace(version) == "" {
+		return "", errorsmod.Wrap(icatypes.ErrInvalidVersion, "version cannot be empty")
+	}
+
+	metadata, err := icatypes.ParseMedataFromString(version)
+	if err != nil {
+		return "", err
+	}
+
+	channel, found := k.channelKeeper.GetChannel(ctx, portID, channelID)
+	if !found {
+		return "", errorsmod.Wrapf(channeltypes.ErrChannelNotFound, "failed to retrieve channel %s on port %s", channelID, portID)
+	}
+
+	currentMetadata, err := icatypes.ParseMedataFromString(channel.Version)
+	if err != nil {
+		return "", err
+	}
+
+	if err := icatypes.ValidateControllerMetadata(ctx, k.channelKeeper, connectionHops, metadata); err != nil {
+		return "", errorsmod.Wrap(err, "invalid metadata")
+	}
+
+	// the interchain account address on the host chain
+	// must remain the same after the upgrade.
+	if currentMetadata.Address != metadata.Address {
+		return "", errorsmod.Wrap(icatypes.ErrInvalidAccountAddress, "address cannot be changed")
+	}
+
+	if currentMetadata.ControllerConnectionId != connectionHops[0] {
+		return "", errorsmod.Wrap(connectiontypes.ErrInvalidConnectionIdentifier, "proposed connection hop must not change")
+	}
+
+	metadataBz := icatypes.ModuleCdc.MustMarshalJSON(&metadata)
+	return string(metadataBz), nil
+}
diff --git a/modules/apps/27-interchain-accounts/controller/keeper/handshake_test.go b/modules/apps/27-interchain-accounts/controller/keeper/handshake_test.go
index 827c37ed74e..ef556f5d9ff 100644
--- a/modules/apps/27-interchain-accounts/controller/keeper/handshake_test.go
+++ b/modules/apps/27-interchain-accounts/controller/keeper/handshake_test.go
@@ -493,14 +493,6 @@ func (suite *KeeperTestSuite) TestOnChanUpgradeInit() {
 			func() {},
 			nil,
 		},
-		{
-			"failure: no changes made in upgrade",
-			func() {
-				// revert the change so that proposed metadata is the same as current.
-				metadata.Encoding = icatypes.EncodingProtobuf
-			},
-			channeltypes.ErrChannelExists,
-		},
 		{
 			name: "failure: invalid metadata",
 			malleate: func() {
@@ -531,6 +523,13 @@ func (suite *KeeperTestSuite) TestOnChanUpgradeInit() {
 			},
 			expError: icatypes.ErrUnknownDataType,
 		},
+		{
+			name: "failure: invalid connection hops",
+			malleate: func() {
+				path.EndpointA.ConnectionID = differentConnectionID
+			},
+			expError: connectiontypes.ErrConnectionNotFound,
+		},
 	}
 
 	for _, tc := range testCases {
@@ -559,18 +558,23 @@ func (suite *KeeperTestSuite) TestOnChanUpgradeInit() {
 
 			tc.malleate() // malleate mutates test data
 
-			path.EndpointA.ChannelConfig.ProposedUpgrade.Fields.Version = string(icatypes.ModuleCdc.MustMarshalJSON(&metadata))
-			path.EndpointB.ChannelConfig.ProposedUpgrade.Fields.Version = string(icatypes.ModuleCdc.MustMarshalJSON(&metadata))
+			version := string(icatypes.ModuleCdc.MustMarshalJSON(&metadata))
 
-			err = path.EndpointA.ChanUpgradeInit()
+			upgradeVersion, err := path.EndpointA.Chain.GetSimApp().ICAControllerKeeper.OnChanUpgradeInit(
+				path.EndpointA.Chain.GetContext(),
+				path.EndpointA.ChannelConfig.PortID,
+				path.EndpointA.ChannelID,
+				[]string{path.EndpointA.ConnectionID},
+				version,
+			)
 
 			expPass := tc.expError == nil
 
 			if expPass {
 				suite.Require().NoError(err)
+				suite.Require().Equal(upgradeVersion, version)
 			} else {
-				suite.Require().Error(err)
-				suite.Require().Contains(err.Error(), tc.expError.Error())
+				suite.Require().ErrorIs(err, tc.expError)
 			}
 		})
 	}
diff --git a/modules/apps/27-interchain-accounts/controller/keeper/keeper.go b/modules/apps/27-interchain-accounts/controller/keeper/keeper.go
index 6a55887db78..63e606c395e 100644
--- a/modules/apps/27-interchain-accounts/controller/keeper/keeper.go
+++ b/modules/apps/27-interchain-accounts/controller/keeper/keeper.go
@@ -85,11 +85,6 @@ func (k Keeper) GetConnectionID(ctx sdk.Context, portID, channelID string) (stri
 	return channel.ConnectionHops[0], nil
 }
 
-// GetChannelKeeper returns the ChannelKeeper
-func (k Keeper) GetChannelKeeper() icatypes.ChannelKeeper {
-	return k.channelKeeper
-}
-
 // GetAllPorts returns all ports to which the interchain accounts controller module is bound. Used in ExportGenesis
 func (k Keeper) GetAllPorts(ctx sdk.Context) []string {
 	store := ctx.KVStore(k.storeKey)
@@ -161,15 +156,6 @@ func (k Keeper) GetOpenActiveChannel(ctx sdk.Context, connectionID, portID strin
 	return "", false
 }
 
-// GetChannel returns the channel associated with the provided portID and channelID.
-func (k Keeper) GetChannel(ctx sdk.Context, portID, channelID string) (channeltypes.Channel, error) {
-	channel, found := k.channelKeeper.GetChannel(ctx, portID, channelID)
-	if !found {
-		return channeltypes.Channel{}, errorsmod.Wrapf(channeltypes.ErrChannelNotFound, "port ID (%s) channel ID (%s)", portID, channelID)
-	}
-	return channel, nil
-}
-
 // IsActiveChannelClosed retrieves the active channel from the store and returns true if the channel state is CLOSED, otherwise false
 func (k Keeper) IsActiveChannelClosed(ctx sdk.Context, connectionID, portID string) bool {
 	channelID, found := k.GetActiveChannelID(ctx, connectionID, portID)

From eb7631407ca6e0c3d66d77098e6b3e7e3342107a Mon Sep 17 00:00:00 2001
From: chatton <github.qpeyb@simplelogin.fr>
Date: Tue, 21 Nov 2023 11:40:30 +0000
Subject: [PATCH 08/13] chore: add check for enabled controller module

---
 .../apps/27-interchain-accounts/controller/ibc_middleware.go  | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/modules/apps/27-interchain-accounts/controller/ibc_middleware.go b/modules/apps/27-interchain-accounts/controller/ibc_middleware.go
index 6fb9a7a357d..81e132b0c2e 100644
--- a/modules/apps/27-interchain-accounts/controller/ibc_middleware.go
+++ b/modules/apps/27-interchain-accounts/controller/ibc_middleware.go
@@ -233,6 +233,10 @@ func (im IBCMiddleware) OnTimeoutPacket(
 
 // OnChanUpgradeInit implements the IBCModule interface
 func (im IBCMiddleware) OnChanUpgradeInit(ctx sdk.Context, portID, channelID string, order channeltypes.Order, connectionHops []string, version string) (string, error) {
+	if !im.keeper.GetParams(ctx).ControllerEnabled {
+		return "", types.ErrControllerSubModuleDisabled
+	}
+
 	return im.keeper.OnChanUpgradeInit(ctx, portID, channelID, connectionHops, version)
 }
 

From 236f2d9bf9c6824c821549f3f567b8ed072856a5 Mon Sep 17 00:00:00 2001
From: chatton <github.qpeyb@simplelogin.fr>
Date: Tue, 21 Nov 2023 13:38:11 +0000
Subject: [PATCH 09/13] chore: call into middleware if provided

---
 .../controller/ibc_middleware.go                 | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/modules/apps/27-interchain-accounts/controller/ibc_middleware.go b/modules/apps/27-interchain-accounts/controller/ibc_middleware.go
index 81e132b0c2e..043afff714d 100644
--- a/modules/apps/27-interchain-accounts/controller/ibc_middleware.go
+++ b/modules/apps/27-interchain-accounts/controller/ibc_middleware.go
@@ -237,7 +237,21 @@ func (im IBCMiddleware) OnChanUpgradeInit(ctx sdk.Context, portID, channelID str
 		return "", types.ErrControllerSubModuleDisabled
 	}
 
-	return im.keeper.OnChanUpgradeInit(ctx, portID, channelID, connectionHops, version)
+	version, err := im.keeper.OnChanUpgradeInit(ctx, portID, channelID, connectionHops, version)
+	if err != nil {
+		return "", err
+	}
+
+	connectionID, err := im.keeper.GetConnectionID(ctx, portID, channelID)
+	if err != nil {
+		return "", err
+	}
+
+	if im.app != nil && im.keeper.IsMiddlewareEnabled(ctx, portID, connectionID) {
+		return im.app.OnChanUpgradeInit(ctx, portID, channelID, order, connectionHops, version)
+	}
+
+	return version, nil
 }
 
 // OnChanUpgradeTry implements the IBCModule interface

From bc477b9682417f28495bac74f2e9e81146de9dbf Mon Sep 17 00:00:00 2001
From: chatton <github.qpeyb@simplelogin.fr>
Date: Wed, 29 Nov 2023 11:20:52 +0000
Subject: [PATCH 10/13] chore: addressing PR feedback

---
 .../controller/keeper/export_test.go               | 12 +++++++++++-
 .../controller/keeper/handshake.go                 | 14 ++++----------
 .../controller/keeper/handshake_test.go            | 10 ++++------
 .../controller/keeper/keeper.go                    | 13 ++++++++++++-
 .../27-interchain-accounts/host/keeper/keeper.go   | 10 ++--------
 .../apps/27-interchain-accounts/types/metadata.go  |  4 ++--
 6 files changed, 35 insertions(+), 28 deletions(-)

diff --git a/modules/apps/27-interchain-accounts/controller/keeper/export_test.go b/modules/apps/27-interchain-accounts/controller/keeper/export_test.go
index 382dde7a805..2cd4338dde2 100644
--- a/modules/apps/27-interchain-accounts/controller/keeper/export_test.go
+++ b/modules/apps/27-interchain-accounts/controller/keeper/export_test.go
@@ -4,9 +4,19 @@ package keeper
 	This file is to allow for unexported functions and fields to be accessible to the testing package.
 */
 
-import porttypes "github.com/cosmos/ibc-go/v8/modules/core/05-port/types"
+import (
+	sdk "github.com/cosmos/cosmos-sdk/types"
+
+	icatypes "github.com/cosmos/ibc-go/v8/modules/apps/27-interchain-accounts/types"
+	porttypes "github.com/cosmos/ibc-go/v8/modules/core/05-port/types"
+)
 
 // GetICS4Wrapper is a getter for the keeper's ICS4Wrapper.
 func (k *Keeper) GetICS4Wrapper() porttypes.ICS4Wrapper {
 	return k.ics4Wrapper
 }
+
+// GetAppMetadata is a wrapper around getAppMetadata to allow the function to be directly called in tests.
+func (k Keeper) GetAppMetadata(ctx sdk.Context, portID, channelID string) (icatypes.Metadata, error) {
+	return k.getAppMetadata(ctx, portID, channelID)
+}
diff --git a/modules/apps/27-interchain-accounts/controller/keeper/handshake.go b/modules/apps/27-interchain-accounts/controller/keeper/handshake.go
index a15fb35f4cf..1bb2ae663d7 100644
--- a/modules/apps/27-interchain-accounts/controller/keeper/handshake.go
+++ b/modules/apps/27-interchain-accounts/controller/keeper/handshake.go
@@ -144,17 +144,12 @@ func (k Keeper) OnChanUpgradeInit(ctx sdk.Context, portID, channelID string, con
 		return "", errorsmod.Wrap(icatypes.ErrInvalidVersion, "version cannot be empty")
 	}
 
-	metadata, err := icatypes.ParseMedataFromString(version)
+	metadata, err := icatypes.MedataFromVersion(version)
 	if err != nil {
 		return "", err
 	}
 
-	channel, found := k.channelKeeper.GetChannel(ctx, portID, channelID)
-	if !found {
-		return "", errorsmod.Wrapf(channeltypes.ErrChannelNotFound, "failed to retrieve channel %s on port %s", channelID, portID)
-	}
-
-	currentMetadata, err := icatypes.ParseMedataFromString(channel.Version)
+	currentMetadata, err := k.getAppMetadata(ctx, portID, channelID)
 	if err != nil {
 		return "", err
 	}
@@ -166,13 +161,12 @@ func (k Keeper) OnChanUpgradeInit(ctx sdk.Context, portID, channelID string, con
 	// the interchain account address on the host chain
 	// must remain the same after the upgrade.
 	if currentMetadata.Address != metadata.Address {
-		return "", errorsmod.Wrap(icatypes.ErrInvalidAccountAddress, "address cannot be changed")
+		return "", errorsmod.Wrap(icatypes.ErrInvalidAccountAddress, "interchain account address cannot be changed")
 	}
 
 	if currentMetadata.ControllerConnectionId != connectionHops[0] {
 		return "", errorsmod.Wrap(connectiontypes.ErrInvalidConnectionIdentifier, "proposed connection hop must not change")
 	}
 
-	metadataBz := icatypes.ModuleCdc.MustMarshalJSON(&metadata)
-	return string(metadataBz), nil
+	return version, nil
 }
diff --git a/modules/apps/27-interchain-accounts/controller/keeper/handshake_test.go b/modules/apps/27-interchain-accounts/controller/keeper/handshake_test.go
index ef556f5d9ff..8dc9211f3da 100644
--- a/modules/apps/27-interchain-accounts/controller/keeper/handshake_test.go
+++ b/modules/apps/27-interchain-accounts/controller/keeper/handshake_test.go
@@ -494,14 +494,14 @@ func (suite *KeeperTestSuite) TestOnChanUpgradeInit() {
 			nil,
 		},
 		{
-			name: "failure: invalid metadata",
+			name: "failure: change ICA address",
 			malleate: func() {
 				metadata.Address = TestOwnerAddress
 			},
 			expError: icatypes.ErrInvalidAccountAddress,
 		},
 		{
-			name: "failure: change connection id",
+			name: "failure: change controller connection id",
 			malleate: func() {
 				metadata.ControllerConnectionId = differentConnectionID
 			},
@@ -515,7 +515,7 @@ func (suite *KeeperTestSuite) TestOnChanUpgradeInit() {
 			expError: connectiontypes.ErrInvalidConnection,
 		},
 		{
-			name: "failure: invalid metadata string",
+			name: "failure: cannot decode version string",
 			malleate: func() {
 				channel := path.EndpointA.GetChannel()
 				channel.Version = "invalid-metadata-string"
@@ -544,9 +544,7 @@ func (suite *KeeperTestSuite) TestOnChanUpgradeInit() {
 			err := SetupICAPath(path, TestOwnerAddress)
 			suite.Require().NoError(err)
 
-			channel := path.EndpointA.GetChannel()
-
-			currentMetadata, err := icatypes.ParseMedataFromString(channel.Version)
+			currentMetadata, err := suite.chainA.GetSimApp().ICAControllerKeeper.GetAppMetadata(suite.chainA.GetContext(), path.EndpointA.ChannelConfig.PortID, path.EndpointA.ChannelID)
 			suite.Require().NoError(err)
 
 			metadata = icatypes.NewDefaultMetadata(path.EndpointA.ConnectionID, path.EndpointB.ConnectionID)
diff --git a/modules/apps/27-interchain-accounts/controller/keeper/keeper.go b/modules/apps/27-interchain-accounts/controller/keeper/keeper.go
index 63e606c395e..b642a50acee 100644
--- a/modules/apps/27-interchain-accounts/controller/keeper/keeper.go
+++ b/modules/apps/27-interchain-accounts/controller/keeper/keeper.go
@@ -20,6 +20,7 @@ import (
 	channeltypes "github.com/cosmos/ibc-go/v8/modules/core/04-channel/types"
 	porttypes "github.com/cosmos/ibc-go/v8/modules/core/05-port/types"
 	host "github.com/cosmos/ibc-go/v8/modules/core/24-host"
+	ibcerrors "github.com/cosmos/ibc-go/v8/modules/core/errors"
 	"github.com/cosmos/ibc-go/v8/modules/core/exported"
 )
 
@@ -76,7 +77,7 @@ func (Keeper) Logger(ctx sdk.Context) log.Logger {
 	return ctx.Logger().With("module", fmt.Sprintf("x/%s-%s", exported.ModuleName, icatypes.ModuleName))
 }
 
-// GetConnectionID returns the connection id for the given port and channelIDs.
+// ConnectionID returns the connection id for the given port and channelIDs.
 func (k Keeper) GetConnectionID(ctx sdk.Context, portID, channelID string) (string, error) {
 	channel, found := k.channelKeeper.GetChannel(ctx, portID, channelID)
 	if !found {
@@ -280,6 +281,16 @@ func (k Keeper) GetAuthority() string {
 	return k.authority
 }
 
+// getAppMetadata retrieves the interchain accounts channel metadata from the store associated with the provided portID and channelID
+func (k Keeper) getAppMetadata(ctx sdk.Context, portID, channelID string) (icatypes.Metadata, error) {
+	appVersion, found := k.GetAppVersion(ctx, portID, channelID)
+	if !found {
+		return icatypes.Metadata{}, errorsmod.Wrapf(ibcerrors.ErrNotFound, "app version not found for port %s and channel %s", portID, channelID)
+	}
+
+	return icatypes.MedataFromVersion(appVersion)
+}
+
 // GetParams returns the current ica/controller submodule parameters.
 func (k Keeper) GetParams(ctx sdk.Context) types.Params {
 	store := ctx.KVStore(k.storeKey)
diff --git a/modules/apps/27-interchain-accounts/host/keeper/keeper.go b/modules/apps/27-interchain-accounts/host/keeper/keeper.go
index c426c4cc0cb..429551f4772 100644
--- a/modules/apps/27-interchain-accounts/host/keeper/keeper.go
+++ b/modules/apps/27-interchain-accounts/host/keeper/keeper.go
@@ -111,20 +111,14 @@ func (k Keeper) GetAppVersion(ctx sdk.Context, portID, channelID string) (string
 	return k.ics4Wrapper.GetAppVersion(ctx, portID, channelID)
 }
 
-// GetAppMetadata retrieves the interchain accounts channel metadata from the store associated with the provided portID and channelID
+// getAppMetadata retrieves the interchain accounts channel metadata from the store associated with the provided portID and channelID
 func (k Keeper) getAppMetadata(ctx sdk.Context, portID, channelID string) (icatypes.Metadata, error) {
 	appVersion, found := k.GetAppVersion(ctx, portID, channelID)
 	if !found {
 		return icatypes.Metadata{}, errorsmod.Wrapf(ibcerrors.ErrNotFound, "app version not found for port %s and channel %s", portID, channelID)
 	}
 
-	var metadata icatypes.Metadata
-	if err := icatypes.ModuleCdc.UnmarshalJSON([]byte(appVersion), &metadata); err != nil {
-		// UnmarshalJSON errors are indeterminate and therefore are not wrapped and included in failed acks
-		return icatypes.Metadata{}, errorsmod.Wrapf(icatypes.ErrUnknownDataType, "cannot unmarshal ICS-27 interchain accounts metadata")
-	}
-
-	return metadata, nil
+	return icatypes.MedataFromVersion(appVersion)
 }
 
 // GetActiveChannelID retrieves the active channelID from the store keyed by the provided connectionID and portID
diff --git a/modules/apps/27-interchain-accounts/types/metadata.go b/modules/apps/27-interchain-accounts/types/metadata.go
index 03e559e8e7d..e1fd2a5ecfc 100644
--- a/modules/apps/27-interchain-accounts/types/metadata.go
+++ b/modules/apps/27-interchain-accounts/types/metadata.go
@@ -54,8 +54,8 @@ func NewDefaultMetadataString(controllerConnectionID, hostConnectionID string) s
 	return string(ModuleCdc.MustMarshalJSON(&metadata))
 }
 
-// ParseMedataFromString parses Metadata from a json encoded version string.
-func ParseMedataFromString(versionString string) (Metadata, error) {
+// MedataFromVersion parses Metadata from a json encoded version string.
+func MedataFromVersion(versionString string) (Metadata, error) {
 	var metadata Metadata
 	if err := ModuleCdc.UnmarshalJSON([]byte(versionString), &metadata); err != nil {
 		return Metadata{}, errorsmod.Wrapf(ErrUnknownDataType, "cannot unmarshal ICS-27 interchain accounts metadata")

From c8c6c6ba99b821c11e6c40562e5ebe055a499057 Mon Sep 17 00:00:00 2001
From: Carlos Rodriguez <carlos@interchain.io>
Date: Sat, 2 Dec 2023 23:02:50 +0100
Subject: [PATCH 11/13] revert change in godoc of GetConnectionID

---
 modules/apps/27-interchain-accounts/controller/keeper/keeper.go | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/modules/apps/27-interchain-accounts/controller/keeper/keeper.go b/modules/apps/27-interchain-accounts/controller/keeper/keeper.go
index b642a50acee..e5e5c18d5d4 100644
--- a/modules/apps/27-interchain-accounts/controller/keeper/keeper.go
+++ b/modules/apps/27-interchain-accounts/controller/keeper/keeper.go
@@ -77,7 +77,7 @@ func (Keeper) Logger(ctx sdk.Context) log.Logger {
 	return ctx.Logger().With("module", fmt.Sprintf("x/%s-%s", exported.ModuleName, icatypes.ModuleName))
 }
 
-// ConnectionID returns the connection id for the given port and channelIDs.
+// GetConnectionID returns the connection id for the given port and channelIDs.
 func (k Keeper) GetConnectionID(ctx sdk.Context, portID, channelID string) (string, error) {
 	channel, found := k.channelKeeper.GetChannel(ctx, portID, channelID)
 	if !found {

From 21773dbb38f342000b306d6e6c3252b3c744af95 Mon Sep 17 00:00:00 2001
From: Damian Nolan <damiannolan@gmail.com>
Date: Tue, 5 Dec 2023 12:09:24 +0100
Subject: [PATCH 12/13] fix: typo in MetadataFromVersion func

---
 .../27-interchain-accounts/controller/keeper/handshake.go     | 2 +-
 .../apps/27-interchain-accounts/controller/keeper/keeper.go   | 2 +-
 modules/apps/27-interchain-accounts/host/keeper/keeper.go     | 2 +-
 modules/apps/27-interchain-accounts/types/metadata.go         | 4 ++--
 4 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/modules/apps/27-interchain-accounts/controller/keeper/handshake.go b/modules/apps/27-interchain-accounts/controller/keeper/handshake.go
index 1bb2ae663d7..b055dff20f8 100644
--- a/modules/apps/27-interchain-accounts/controller/keeper/handshake.go
+++ b/modules/apps/27-interchain-accounts/controller/keeper/handshake.go
@@ -144,7 +144,7 @@ func (k Keeper) OnChanUpgradeInit(ctx sdk.Context, portID, channelID string, con
 		return "", errorsmod.Wrap(icatypes.ErrInvalidVersion, "version cannot be empty")
 	}
 
-	metadata, err := icatypes.MedataFromVersion(version)
+	metadata, err := icatypes.MetadataFromVersion(version)
 	if err != nil {
 		return "", err
 	}
diff --git a/modules/apps/27-interchain-accounts/controller/keeper/keeper.go b/modules/apps/27-interchain-accounts/controller/keeper/keeper.go
index e5e5c18d5d4..4e11ea993e7 100644
--- a/modules/apps/27-interchain-accounts/controller/keeper/keeper.go
+++ b/modules/apps/27-interchain-accounts/controller/keeper/keeper.go
@@ -288,7 +288,7 @@ func (k Keeper) getAppMetadata(ctx sdk.Context, portID, channelID string) (icaty
 		return icatypes.Metadata{}, errorsmod.Wrapf(ibcerrors.ErrNotFound, "app version not found for port %s and channel %s", portID, channelID)
 	}
 
-	return icatypes.MedataFromVersion(appVersion)
+	return icatypes.MetadataFromVersion(appVersion)
 }
 
 // GetParams returns the current ica/controller submodule parameters.
diff --git a/modules/apps/27-interchain-accounts/host/keeper/keeper.go b/modules/apps/27-interchain-accounts/host/keeper/keeper.go
index 429551f4772..be0cfc8a0b5 100644
--- a/modules/apps/27-interchain-accounts/host/keeper/keeper.go
+++ b/modules/apps/27-interchain-accounts/host/keeper/keeper.go
@@ -118,7 +118,7 @@ func (k Keeper) getAppMetadata(ctx sdk.Context, portID, channelID string) (icaty
 		return icatypes.Metadata{}, errorsmod.Wrapf(ibcerrors.ErrNotFound, "app version not found for port %s and channel %s", portID, channelID)
 	}
 
-	return icatypes.MedataFromVersion(appVersion)
+	return icatypes.MetadataFromVersion(appVersion)
 }
 
 // GetActiveChannelID retrieves the active channelID from the store keyed by the provided connectionID and portID
diff --git a/modules/apps/27-interchain-accounts/types/metadata.go b/modules/apps/27-interchain-accounts/types/metadata.go
index e1fd2a5ecfc..d3c0f32a5f5 100644
--- a/modules/apps/27-interchain-accounts/types/metadata.go
+++ b/modules/apps/27-interchain-accounts/types/metadata.go
@@ -54,8 +54,8 @@ func NewDefaultMetadataString(controllerConnectionID, hostConnectionID string) s
 	return string(ModuleCdc.MustMarshalJSON(&metadata))
 }
 
-// MedataFromVersion parses Metadata from a json encoded version string.
-func MedataFromVersion(versionString string) (Metadata, error) {
+// MetadataFromVersion parses Metadata from a json encoded version string.
+func MetadataFromVersion(versionString string) (Metadata, error) {
 	var metadata Metadata
 	if err := ModuleCdc.UnmarshalJSON([]byte(versionString), &metadata); err != nil {
 		return Metadata{}, errorsmod.Wrapf(ErrUnknownDataType, "cannot unmarshal ICS-27 interchain accounts metadata")

From f1c10fdf105016bee7cab6c88ba9db51f2202498 Mon Sep 17 00:00:00 2001
From: Damian Nolan <damiannolan@gmail.com>
Date: Tue, 5 Dec 2023 12:58:10 +0100
Subject: [PATCH 13/13] chore: rm duplicate func

---
 modules/apps/27-interchain-accounts/types/metadata.go | 9 ---------
 1 file changed, 9 deletions(-)

diff --git a/modules/apps/27-interchain-accounts/types/metadata.go b/modules/apps/27-interchain-accounts/types/metadata.go
index 99b39a83c10..61c077a46f0 100644
--- a/modules/apps/27-interchain-accounts/types/metadata.go
+++ b/modules/apps/27-interchain-accounts/types/metadata.go
@@ -174,12 +174,3 @@ func validateConnectionParams(metadata Metadata, controllerConnectionID, hostCon
 
 	return nil
 }
-
-// MetadataFromVersion parses Metadata from a json encoded version string.
-func MetadataFromVersion(versionString string) (Metadata, error) {
-	var metadata Metadata
-	if err := ModuleCdc.UnmarshalJSON([]byte(versionString), &metadata); err != nil {
-		return Metadata{}, errorsmod.Wrapf(ErrUnknownDataType, "cannot unmarshal ICS-27 interchain accounts metadata")
-	}
-	return metadata, nil
-}