support fo governance keeper hooks returning errors

x/gov/abci.go

@@ -31,7 +31,13 @@ func EndBlocker(ctx sdk.Context, keeper *keeper.Keeper) {
 		}
 
 		// called when proposal become inactive
-		keeper.Hooks().AfterProposalFailedMinDeposit(ctx, proposal.Id)
+		cacheCtx, writeCache := ctx.CacheContext()
+		err := keeper.Hooks().AfterProposalFailedMinDeposit(cacheCtx, proposal.Id)
+		if err == nil { // purposely ignoring the error here not to halt the chain if the hook fails
+			writeCache()
+		} else {
+			keeper.Logger(ctx).Error("failed to execute AfterProposalFailedMinDeposit hook", "error", err)
+		}
 
 		ctx.EventManager().EmitEvent(
 			sdk.NewEvent(
@@ -118,7 +124,13 @@ func EndBlocker(ctx sdk.Context, keeper *keeper.Keeper) {
 		keeper.RemoveFromActiveProposalQueue(ctx, proposal.Id, *proposal.VotingEndTime)
 
 		// when proposal become active
-		keeper.Hooks().AfterProposalVotingPeriodEnded(ctx, proposal.Id)
+		cacheCtx, writeCache := ctx.CacheContext()
+		err := keeper.Hooks().AfterProposalVotingPeriodEnded(cacheCtx, proposal.Id)
+		if err == nil { // purposely ignoring the error here not to halt the chain if the hook fails
+			writeCache()
+		} else {
+			keeper.Logger(ctx).Error("failed to execute AfterProposalVotingPeriodEnded hook", "error", err)
+		}
 
 		logger.Info(
 			"proposal tallied",

x/gov/keeper/deposit.go

@@ -147,7 +147,10 @@ func (keeper Keeper) AddDeposit(ctx sdk.Context, proposalID uint64, depositorAdd
 	}
 
 	// called when deposit has been added to a proposal, however the proposal may not be active
-	keeper.Hooks().AfterProposalDeposit(ctx, proposalID, depositorAddr)
+	err = keeper.Hooks().AfterProposalDeposit(ctx, proposalID, depositorAddr)
+	if err != nil {
+		return false, err
+	}
 
 	ctx.EventManager().EmitEvent(
 		sdk.NewEvent(

x/gov/keeper/hooks_test.go

@@ -25,24 +25,29 @@ type MockGovHooksReceiver struct {
 	AfterProposalVotingPeriodEndedValid bool
 }
 
-func (h *MockGovHooksReceiver) AfterProposalSubmission(ctx sdk.Context, proposalID uint64) {
+func (h *MockGovHooksReceiver) AfterProposalSubmission(ctx sdk.Context, proposalID uint64) error {
 	h.AfterProposalSubmissionValid = true
+	return nil
 }
 
-func (h *MockGovHooksReceiver) AfterProposalDeposit(ctx sdk.Context, proposalID uint64, depositorAddr sdk.AccAddress) {
+func (h *MockGovHooksReceiver) AfterProposalDeposit(ctx sdk.Context, proposalID uint64, depositorAddr sdk.AccAddress) error {
 	h.AfterProposalDepositValid = true
+	return nil
 }
 
-func (h *MockGovHooksReceiver) AfterProposalVote(ctx sdk.Context, proposalID uint64, voterAddr sdk.AccAddress) {
+func (h *MockGovHooksReceiver) AfterProposalVote(ctx sdk.Context, proposalID uint64, voterAddr sdk.AccAddress) error {
 	h.AfterProposalVoteValid = true
+	return nil
 }
 
-func (h *MockGovHooksReceiver) AfterProposalFailedMinDeposit(ctx sdk.Context, proposalID uint64) {
+func (h *MockGovHooksReceiver) AfterProposalFailedMinDeposit(ctx sdk.Context, proposalID uint64) error {
 	h.AfterProposalFailedMinDepositValid = true
+	return nil
 }
 
-func (h *MockGovHooksReceiver) AfterProposalVotingPeriodEnded(ctx sdk.Context, proposalID uint64) {
+func (h *MockGovHooksReceiver) AfterProposalVotingPeriodEnded(ctx sdk.Context, proposalID uint64) error {
 	h.AfterProposalVotingPeriodEndedValid = true
+	return nil
 }
 
 func TestHooks(t *testing.T) {

x/gov/keeper/proposal.go

@@ -94,7 +94,10 @@ func (keeper Keeper) SubmitProposal(ctx sdk.Context, messages []sdk.Msg, metadat
 	keeper.SetProposalID(ctx, proposalID+1)
 
 	// called right after a proposal is submitted
-	keeper.Hooks().AfterProposalSubmission(ctx, proposalID)
+	err = keeper.Hooks().AfterProposalSubmission(ctx, proposalID)
+	if err != nil {
+		return v1.Proposal{}, err
+	}
 
 	ctx.EventManager().EmitEvent(
 		sdk.NewEvent(

x/gov/keeper/vote.go

@@ -32,7 +32,10 @@ func (keeper Keeper) AddVote(ctx sdk.Context, proposalID uint64, voterAddr sdk.A
 	keeper.SetVote(ctx, vote)
 
 	// called after a vote on a proposal is cast
-	keeper.Hooks().AfterProposalVote(ctx, proposalID, voterAddr)
+	err = keeper.Hooks().AfterProposalVote(ctx, proposalID, voterAddr)
+	if err != nil {
+		return err
+	}
 
 	ctx.EventManager().EmitEvent(
 		sdk.NewEvent(

x/gov/types/expected_keepers.go

@@ -56,11 +56,11 @@ type BankKeeper interface {
 
 // GovHooks event hooks for governance proposal object (noalias)
 type GovHooks interface {
-	AfterProposalSubmission(ctx sdk.Context, proposalID uint64)                            // Must be called after proposal is submitted
-	AfterProposalDeposit(ctx sdk.Context, proposalID uint64, depositorAddr sdk.AccAddress) // Must be called after a deposit is made
-	AfterProposalVote(ctx sdk.Context, proposalID uint64, voterAddr sdk.AccAddress)        // Must be called after a vote on a proposal is cast
-	AfterProposalFailedMinDeposit(ctx sdk.Context, proposalID uint64)                      // Must be called when proposal fails to reach min deposit
-	AfterProposalVotingPeriodEnded(ctx sdk.Context, proposalID uint64)                     // Must be called when proposal's finishes it's voting period
+	AfterProposalSubmission(ctx sdk.Context, proposalID uint64) error                            // Must be called after proposal is submitted
+	AfterProposalDeposit(ctx sdk.Context, proposalID uint64, depositorAddr sdk.AccAddress) error // Must be called after a deposit is made
+	AfterProposalVote(ctx sdk.Context, proposalID uint64, voterAddr sdk.AccAddress) error        // Must be called after a vote on a proposal is cast
+	AfterProposalFailedMinDeposit(ctx sdk.Context, proposalID uint64) error                      // Must be called when proposal fails to reach min deposit
+	AfterProposalVotingPeriodEnded(ctx sdk.Context, proposalID uint64) error                     // Must be called when proposal's finishes it's voting period
 }
 
 type GovHooksWrapper struct{ GovHooks }

x/gov/types/hooks.go

@@ -13,32 +13,79 @@ func NewMultiGovHooks(hooks ...GovHooks) MultiGovHooks {
 	return hooks
 }
 
-func (h MultiGovHooks) AfterProposalSubmission(ctx sdk.Context, proposalID uint64) {
+func (h MultiGovHooks) AfterProposalSubmission(ctx sdk.Context, proposalID uint64) error {
+	var errs error
 	for i := range h {
-		h[i].AfterProposalSubmission(ctx, proposalID)
+		errs = JoinErrors(errs, h[i].AfterProposalSubmission(ctx, proposalID))
 	}
+	return errs
 }
 
-func (h MultiGovHooks) AfterProposalDeposit(ctx sdk.Context, proposalID uint64, depositorAddr sdk.AccAddress) {
+func (h MultiGovHooks) AfterProposalDeposit(ctx sdk.Context, proposalID uint64, depositorAddr sdk.AccAddress) error {
+	var errs error
 	for i := range h {
-		h[i].AfterProposalDeposit(ctx, proposalID, depositorAddr)
+		errs = JoinErrors(errs, h[i].AfterProposalDeposit(ctx, proposalID, depositorAddr))
 	}
+	return errs
 }
 
-func (h MultiGovHooks) AfterProposalVote(ctx sdk.Context, proposalID uint64, voterAddr sdk.AccAddress) {
+func (h MultiGovHooks) AfterProposalVote(ctx sdk.Context, proposalID uint64, voterAddr sdk.AccAddress) error {
+	var errs error
 	for i := range h {
-		h[i].AfterProposalVote(ctx, proposalID, voterAddr)
+		errs = JoinErrors(errs, h[i].AfterProposalVote(ctx, proposalID, voterAddr))
 	}
+	return errs
 }
 
-func (h MultiGovHooks) AfterProposalFailedMinDeposit(ctx sdk.Context, proposalID uint64) {
+func (h MultiGovHooks) AfterProposalFailedMinDeposit(ctx sdk.Context, proposalID uint64) error {
+	var errs error
 	for i := range h {
-		h[i].AfterProposalFailedMinDeposit(ctx, proposalID)
+		errs = JoinErrors(errs, h[i].AfterProposalFailedMinDeposit(ctx, proposalID))
 	}
+	return errs
 }
 
-func (h MultiGovHooks) AfterProposalVotingPeriodEnded(ctx sdk.Context, proposalID uint64) {
+func (h MultiGovHooks) AfterProposalVotingPeriodEnded(ctx sdk.Context, proposalID uint64) error {
+	var errs error
 	for i := range h {
-		h[i].AfterProposalVotingPeriodEnded(ctx, proposalID)
+		errs = JoinErrors(errs, h[i].AfterProposalVotingPeriodEnded(ctx, proposalID))
 	}
+	return errs
+}
+
+// implementation of errors.Join() in Go 1.20, until we upgrade to that version
+func JoinErrors(errs ...error) error {
+	n := 0
+	for _, err := range errs {
+		if err != nil {
+			n++
+		}
+	}
+	if n == 0 {
+		return nil
+	}
+	e := &joinError{
+		errs: make([]error, 0, n),
+	}
+	for _, err := range errs {
+		if err != nil {
+			e.errs = append(e.errs, err)
+		}
+	}
+	return e
+}
+
+type joinError struct {
+	errs []error
+}
+
+func (e *joinError) Error() string {
+	var b []byte
+	for i, err := range e.errs {
+		if i > 0 {
+			b = append(b, '\n')
+		}
+		b = append(b, err.Error()...)
+	}
+	return string(b)
 }