From a0a8af2184801012d8bb01f4899de2b320b82cd0 Mon Sep 17 00:00:00 2001
From: "mergify[bot]" <37929162+mergify[bot]@users.noreply.github.com>
Date: Tue, 20 Sep 2022 16:54:32 +0200
Subject: [PATCH] fix: add nil checks for controller and host keeper services
 (backport #2308) (#2316)
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* fix: add nil checks for controller and host keeper services (#2308)

## Description

closes: #XXXX

---

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 888c4a0117bfa9753ac4b1ffd1ea81c09867e335)

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

* fix merge conflicts

Co-authored-by: colin axnér <25233464+colin-axner@users.noreply.github.com>
---
 CHANGELOG.md                                  |  3 ++-
 modules/apps/27-interchain-accounts/module.go | 10 ++++++++--
 2 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 71ff1c9129e..bba989f5434 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -62,7 +62,8 @@ Ref: https://keepachangelog.com/en/1.0.0/
 * (apps/27-interchain-accounts) [\#2193](https://github.com/cosmos/ibc-go/pull/2193) Adding `InterchainAccount` gRPC query endpont to ICS27 `controller` submodule to allow users to retrieve registered interchain account addresses.
 
 ### Bug Fixes
- 
+
+* (27-interchain-accounts) [\#2308](https://github.com/cosmos/ibc-go/pull/2308) Nil checks have been added to ensure services are not registered for nil host or controller keepers.
 * (makefile) [\#1785](https://github.com/cosmos/ibc-go/pull/1785) Fetch the correct versions of protocol buffers dependencies from tendermint, cosmos-sdk, and ics23.
 * (modules/core/04-channel)[\#1919](https://github.com/cosmos/ibc-go/pull/1919) Fixed formatting of sequence for packet "acknowledgement written" logs.
 
diff --git a/modules/apps/27-interchain-accounts/module.go b/modules/apps/27-interchain-accounts/module.go
index 47166bddfa0..da1e64d3e5b 100644
--- a/modules/apps/27-interchain-accounts/module.go
+++ b/modules/apps/27-interchain-accounts/module.go
@@ -74,6 +74,7 @@ func (AppModuleBasic) RegisterGRPCGatewayRoutes(clientCtx client.Context, mux *r
 	if err != nil {
 		panic(err)
 	}
+
 	err = hosttypes.RegisterQueryHandlerClient(context.Background(), mux, hosttypes.NewQueryClient(clientCtx))
 	if err != nil {
 		panic(err)
@@ -148,8 +149,13 @@ func (am AppModule) LegacyQuerierHandler(legacyQuerierCdc *codec.LegacyAmino) sd
 
 // RegisterServices registers module services
 func (am AppModule) RegisterServices(cfg module.Configurator) {
-	controllertypes.RegisterQueryServer(cfg.QueryServer(), am.controllerKeeper)
-	hosttypes.RegisterQueryServer(cfg.QueryServer(), am.hostKeeper)
+	if am.controllerKeeper != nil {
+		controllertypes.RegisterQueryServer(cfg.QueryServer(), am.controllerKeeper)
+	}
+
+	if am.hostKeeper != nil {
+		hosttypes.RegisterQueryServer(cfg.QueryServer(), am.hostKeeper)
+	}
 }
 
 // InitGenesis performs genesis initialization for the interchain accounts module.