Added interface to accept any type of ADR 031 message router. (backport

#2058) (#2087)

* Added interface to accept any type of ADR 031 message router.  (#2058)

## Description

Updated the controller and host keeper to take in an interface for the router. This allows systems that implement ADR 031, but do not use the default baseapp.router to use ICA.

closes: #2044

---

Before we can merge this PR, please make sure that all the following items have been
checked off. If any of the checklist items are not applicable, please leave them but
write a little note why.

- [ ] Targeted PR against correct branch (see [CONTRIBUTING.md](https://github.com/cosmos/ibc-go/blob/master/CONTRIBUTING.md#pr-targeting))
- [ ] Linked to Github issue with discussion and accepted design OR link to spec that describes this work.
- [ ] Code follows the [module structure standards](https://github.com/cosmos/cosmos-sdk/blob/master/docs/building-modules/structure.md).
- [ ] Wrote unit and integration [tests](https://github.com/cosmos/ibc-go/blob/master/CONTRIBUTING.md#testing)
- [ ] Updated relevant documentation (`docs/`) or specification (`x/<module>/spec/`)
- [ ] Added relevant `godoc` [comments](https://blog.golang.org/godoc-documenting-go-code).
- [ ] Added a relevant changelog entry to the `Unreleased` section in `CHANGELOG.md`
- [ ] Re-reviewed `Files changed` in the Github PR explorer
- [ ] Review `Codecov Report` in the comment section below once CI passes

(cherry picked from commit 397b88c)

# Conflicts:
#	CHANGELOG.md
#	modules/apps/27-interchain-accounts/controller/keeper/keeper.go
#	modules/apps/27-interchain-accounts/host/keeper/keeper.go

* fix conflict

* fix conflict

* Update keeper.go

* Update keeper.go

* Update keeper.go

Co-authored-by: Matt Witkowski <[email protected]>
Co-authored-by: Carlos Rodriguez <[email protected]>
Co-authored-by: Damian Nolan <[email protected]>

CHANGELOG.md

@@ -47,6 +47,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 * (core/ante) [\#1418](https://github.com/cosmos/ibc-go/pull/1418) `AnteDecorator` has been renamed to `RedundancyDecorator` to comply with go linting rules and to give more clarity to the purpose of the Decorator.
 * (core/ante) [\#1820](https://github.com/cosmos/ibc-go/pull/1418) `RedundancyDecorator` has been renamed to `RedundantRelayDecorator` to make the name for explicit.
 * (testing) [\#1418](https://github.com/cosmos/ibc-go/pull/1418) `MockIBCApp` has been renamed to `IBCApp` and `MockEmptyAcknowledgement` has been renamed to `EmptyAcknowledgement` to comply with go linting rules
+* (apps/27-interchain-accounts) [\#2058](https://github.com/cosmos/ibc-go/pull/2058) Added `MessageRouter` interface and replaced `*baseapp.MsgServiceRouter` with it. The controller and host keepers of apps/27-interchain-accounts have been updated to use it.
 
 ### State Machine Breaking
 

modules/apps/27-interchain-accounts/controller/keeper/keeper.go

@@ -4,7 +4,6 @@ import (
 	"fmt"
 	"strings"
 
-	baseapp "github.com/cosmos/cosmos-sdk/baseapp"
 	"github.com/cosmos/cosmos-sdk/codec"
 	storetypes "github.com/cosmos/cosmos-sdk/store/types"
 	sdk "github.com/cosmos/cosmos-sdk/types"
@@ -31,14 +30,14 @@ type Keeper struct {
 
 	scopedKeeper capabilitykeeper.ScopedKeeper
 
-	msgRouter *baseapp.MsgServiceRouter
+	msgRouter icatypes.MessageRouter
 }
 
 // NewKeeper creates a new interchain accounts controller Keeper instance
 func NewKeeper(
 	cdc codec.BinaryCodec, key storetypes.StoreKey, paramSpace paramtypes.Subspace,
 	ics4Wrapper icatypes.ICS4Wrapper, channelKeeper icatypes.ChannelKeeper, portKeeper icatypes.PortKeeper,
-	scopedKeeper capabilitykeeper.ScopedKeeper, msgRouter *baseapp.MsgServiceRouter,
+	scopedKeeper capabilitykeeper.ScopedKeeper, msgRouter icatypes.MessageRouter,
 ) Keeper {
 	// set KeyTable if it has not already been set
 	if !paramSpace.HasKeyTable() {

modules/apps/27-interchain-accounts/host/keeper/keeper.go

@@ -4,7 +4,6 @@ import (
 	"fmt"
 	"strings"
 
-	baseapp "github.com/cosmos/cosmos-sdk/baseapp"
 	"github.com/cosmos/cosmos-sdk/codec"
 	storetypes "github.com/cosmos/cosmos-sdk/store/types"
 	sdk "github.com/cosmos/cosmos-sdk/types"
@@ -31,14 +30,14 @@ type Keeper struct {
 
 	scopedKeeper capabilitykeeper.ScopedKeeper
 
-	msgRouter *baseapp.MsgServiceRouter
+	msgRouter icatypes.MessageRouter
 }
 
 // NewKeeper creates a new interchain accounts host Keeper instance
 func NewKeeper(
 	cdc codec.BinaryCodec, key storetypes.StoreKey, paramSpace paramtypes.Subspace,
 	channelKeeper icatypes.ChannelKeeper, portKeeper icatypes.PortKeeper,
-	accountKeeper icatypes.AccountKeeper, scopedKeeper capabilitykeeper.ScopedKeeper, msgRouter *baseapp.MsgServiceRouter,
+	accountKeeper icatypes.AccountKeeper, scopedKeeper capabilitykeeper.ScopedKeeper, msgRouter icatypes.MessageRouter,
 ) Keeper {
 	// ensure ibc interchain accounts module account is set
 	if addr := accountKeeper.GetModuleAddress(icatypes.ModuleName); addr == nil {

modules/apps/27-interchain-accounts/types/router.go

@@ -0,0 +1,12 @@
+package types
+
+import (
+	baseapp "github.com/cosmos/cosmos-sdk/baseapp"
+	sdk "github.com/cosmos/cosmos-sdk/types"
+)
+
+// MessageRouter ADR 031 request type routing
+// https://github.com/cosmos/cosmos-sdk/blob/main/docs/architecture/adr-031-msg-service.md
+type MessageRouter interface {
+	Handler(msg sdk.Msg) baseapp.MsgServiceHandler
+}