From b58b34826948e6d0878bb4604d1114d2c26787f4 Mon Sep 17 00:00:00 2001
From: Shawn <44221603+smarshall-spitzbart@users.noreply.github.com>
Date: Wed, 12 Jul 2023 07:59:13 -0700
Subject: [PATCH] feat: remove consumer panic when ccv channel is closed 
 (#1127)

* rm panic

* rm tests

* Update CHANGELOG.md

* update comment
---
 CHANGELOG.md                       |  8 ++++++++
 tests/integration/stop_consumer.go | 28 ----------------------------
 testutil/integration/debug_test.go |  4 ----
 x/ccv/consumer/module.go           |  5 +----
 4 files changed, 9 insertions(+), 36 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 92dc3b5efb..b984d03c08 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,14 @@ Add an entry to the unreleased section whenever merging a PR to main that is not
 * (fix) [#720](https://github.com/cosmos/interchain-security/issues/720) Fix the attribute `AttributeDistributionTotal` value in `FeeDistribution` event emit.
 * (deps) [#1119](https://github.com/cosmos/interchain-security/pull/1119) bump cometbft from `v0.37.1` to `0.37.2`.
 
+## v3.1.0
+
+Date July 11th, 2023
+
+A minor upgrade to v3.0.0, which removes the panic in the consumer ccv module which would occur in an emergency scenario where the ccv channel is closed.
+
+* (feat) [#1127](https://github.com/cosmos/interchain-security/pull/1127) Remove consumer panic when ccv channel is closed
+
 ## v3.0.0
 
 Date: June 21st, 2023
diff --git a/tests/integration/stop_consumer.go b/tests/integration/stop_consumer.go
index f6e0d77d59..5e66301ae2 100644
--- a/tests/integration/stop_consumer.go
+++ b/tests/integration/stop_consumer.go
@@ -1,7 +1,6 @@
 package integration
 
 import (
-	abci "github.com/cometbft/cometbft/abci/types"
 	sdk "github.com/cosmos/cosmos-sdk/types"
 	stakingtypes "github.com/cosmos/cosmos-sdk/x/staking/types"
 	channeltypes "github.com/cosmos/ibc-go/v7/modules/core/04-channel/types"
@@ -211,30 +210,3 @@ func (s *CCVTestSuite) checkConsumerChainIsRemoved(chainID string, checkChannel
 	s.Require().Empty(slashData)
 	s.Require().Empty(vscMaturedData)
 }
-
-// TestProviderChannelClosed checks that a consumer chain panics
-// when the provider channel was established and then closed
-func (suite *CCVTestSuite) TestProviderChannelClosed() {
-	suite.SetupCCVChannel(suite.path)
-	// establish provider channel with a first VSC packet
-	suite.SendEmptyVSCPacket()
-
-	consumerKeeper := suite.consumerApp.GetConsumerKeeper()
-
-	channelID, found := consumerKeeper.GetProviderChannel(suite.consumerChain.GetContext())
-	suite.Require().True(found)
-
-	// close provider channel
-	err := consumerKeeper.ChanCloseInit(suite.consumerChain.GetContext(), ccv.ConsumerPortID, channelID)
-	suite.Require().NoError(err)
-	suite.Require().True(consumerKeeper.IsChannelClosed(suite.consumerChain.GetContext(), channelID))
-
-	// assert begin blocker did panics
-	defer func() {
-		if r := recover(); r != nil {
-			return
-		}
-		suite.Require().Fail("Begin blocker did not panic with a closed channel")
-	}()
-	suite.consumerApp.BeginBlocker(suite.consumerChain.GetContext(), abci.RequestBeginBlock{})
-}
diff --git a/testutil/integration/debug_test.go b/testutil/integration/debug_test.go
index 3d04c540ee..077f33cde3 100644
--- a/testutil/integration/debug_test.go
+++ b/testutil/integration/debug_test.go
@@ -157,10 +157,6 @@ func TestStopConsumerOnChannelClosed(t *testing.T) {
 	runCCVTestByName(t, "TestStopConsumerOnChannelClosed")
 }
 
-func TestProviderChannelClosed(t *testing.T) {
-	runCCVTestByName(t, "TestProviderChannelClosed")
-}
-
 //
 // Throttle tests
 //
diff --git a/x/ccv/consumer/module.go b/x/ccv/consumer/module.go
index 3d80fb1df1..d573bfedeb 100644
--- a/x/ccv/consumer/module.go
+++ b/x/ccv/consumer/module.go
@@ -144,12 +144,9 @@ func (am AppModule) BeginBlock(ctx sdk.Context, req abci.RequestBeginBlock) {
 	channelID, found := am.keeper.GetProviderChannel(ctx)
 	if found && am.keeper.IsChannelClosed(ctx, channelID) {
 		// The CCV channel was established, but it was then closed;
-		// the consumer chain is no longer safe, thus it MUST shut down.
-		// This is achieved by panicking, similar as it's done in the
-		// x/upgrade module of cosmos-sdk.
+		// the consumer chain is not secured anymore, but we allow it to run as a POA chain and log an error.
 		channelClosedMsg := fmt.Sprintf("CCV channel %q was closed - shutdown consumer chain since it is not secured anymore", channelID)
 		am.keeper.Logger(ctx).Error(channelClosedMsg)
-		panic(channelClosedMsg)
 	}
 
 	// map next block height to the vscID of the current block height