Address initial feedback.

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

@@ -33,6 +33,8 @@ type Keeper struct {
 	stakingKeeper  types.StakingKeeper
 	upgradeKeeper  types.UpgradeKeeper
 
+	// the address capable of executing a MsgUpdateClientParams message. Typically, this
+	// should be the x/gov module account.
 	authority string
 }
 

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

@@ -14,13 +14,13 @@ func (k Keeper) GetAllowedClients(ctx sdk.Context) []string {
 
 // GetParams returns the total set of ibc-client parameters.
 func (k Keeper) GetParams(ctx sdk.Context) types.Params {
+	var p types.Params
 	store := ctx.KVStore(k.storeKey)
 	bz := store.Get([]byte(types.ParamsKey))
 	if bz == nil {
-		panic("ibc client params are not set in store")
+		return p
 	}
 
-	var p types.Params
 	k.cdc.MustUnmarshal(bz, &p)
 	return p
 }

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

@@ -46,14 +46,12 @@ func (suite *KeeperTestSuite) TestParams() {
 	}
 }
 
-// TestUnsetParams tests that trying to get params that are not set panics.
+// TestUnsetParams tests that trying to get params that are not set returns empty params.
 func (suite *KeeperTestSuite) TestUnsetParams() {
 	suite.SetupTest()
 	ctx := suite.chainA.GetContext()
 	store := ctx.KVStore(suite.chainA.GetSimApp().GetKey(ibcexported.StoreKey))
 	store.Delete([]byte(types.ParamsKey))
 
-	suite.Require().Panics(func() {
-		suite.chainA.GetSimApp().IBCKeeper.ClientKeeper.GetParams(ctx)
-	})
+	suite.Require().Equal(suite.chainA.GetSimApp().IBCKeeper.ClientKeeper.GetParams(ctx), types.Params{})
 }

modules/core/02-client/types/params_legacy.go

@@ -1,3 +1,9 @@
+/*
+NOTE: Usage of x/params to manage parameters is deprecated in favor of x/gov
+controlled execution of MsgUpdateParams messages. These types remains solely
+for migration purposes and will be removed in a future release.
+[#3621](https://github.com/cosmos/ibc-go/issues/3621)
+*/
 package types
 
 import (

modules/core/02-client/types/params_test.go

@@ -15,10 +15,10 @@ func TestIsAllowedClient(t *testing.T) {
 		params     Params
 		expPass    bool
 	}{
-		{"valid client", exported.Tendermint, DefaultParams(), true},
-		{"valid client with custom params", exported.Tendermint, NewParams(exported.Tendermint), true},
-		{"invalid blank client", " ", DefaultParams(), false},
-		{"invalid client with custom params", exported.Localhost, NewParams(exported.Tendermint), false},
+		{"success: valid client", exported.Tendermint, DefaultParams(), true},
+		{"sucess: valid client with custom params", exported.Tendermint, NewParams(exported.Tendermint), true},
+		{"success: invalid blank client", " ", DefaultParams(), false},
+		{"sucess: invalid client with custom params", exported.Localhost, NewParams(exported.Tendermint), false},
 	}
 
 	for _, tc := range testCases {

proto/ibc/core/client/v1/tx.proto

@@ -5,10 +5,9 @@ package ibc.core.client.v1;
 option go_package = "github.com/cosmos/ibc-go/v7/modules/core/02-client/types";
 
 import "cosmos_proto/cosmos.proto";
-import "cosmos/msg/v1/msg.proto";
-import "ibc/core/client/v1/client.proto";
 import "gogoproto/gogo.proto";
 import "google/protobuf/any.proto";
+import "ibc/core/client/v1/client.proto";
 
 // Msg defines the ibc/client Msg service.
 service Msg {
@@ -107,8 +106,6 @@ message MsgSubmitMisbehaviourResponse {}
 
 // MsgUpdateClientParams defines the sdk.Msg type to update the client parameters.
 message MsgUpdateClientParams {
-  option (cosmos.msg.v1.signer) = "authority";
-
   // authority is the address of the governance account.
   string authority = 1 [(cosmos_proto.scalar) = "cosmos.AddressString"];