improve repayment cet signing

Author: keithsue

x/lending/keeper/approval.go

@@ -14,11 +14,6 @@ func (k Keeper) HandleApproval(ctx sdk.Context, loan *types.Loan) error {
 		return types.ErrInsufficientLiquidity
 	}
 
-	// initiate signing request for repayment cet adaptor signatures from DCM
-	if err := k.InitiateRepaymentCetSigningRequest(ctx, loan.VaultAddress); err != nil {
-		return err
-	}
-
 	amount := sdk.NewCoin(loan.BorrowAmount.Denom, loan.BorrowAmount.Amount.Sub(loan.OriginationFee))
 	if err := k.bankKeeper.SendCoinsFromModuleToAccount(ctx, types.ModuleName, sdk.MustAccAddressFromBech32(loan.Borrower), sdk.NewCoins(amount)); err != nil {
 		// unexpected error

x/lending/keeper/msg_server_loan.go

@@ -214,6 +214,11 @@ func (m msgServer) SubmitCets(goCtx context.Context, msg *types.MsgSubmitCets) (
 		return nil, err
 	}
 
+	// initiate signing request for repayment cet adaptor signatures from DCM
+	if err := m.InitiateRepaymentCetSigningRequest(ctx, loan.VaultAddress); err != nil {
+		return nil, err
+	}
+
 	// create authorization
 	authorization := m.CreateAuthorization(ctx, msg.LoanId, depositTxHashes)
 

x/lending/keeper/repayment.go

@@ -47,8 +47,8 @@ func (k Keeper) HandleRepaymentAdaptorSignatures(ctx sdk.Context, loanId string,
 	}
 
 	loan := k.GetLoan(ctx, loanId)
-	if loan.Status != types.LoanStatus_Open && loan.Status != types.LoanStatus_Repaid {
-		return errorsmod.Wrap(types.ErrInvalidLoanStatus, "loan neither open nor repaid")
+	if types.LoanDisbursed(loan) {
+		return errorsmod.Wrap(types.ErrInvalidLoanStatus, "loan has been disbursed")
 	}
 
 	dlcMeta := k.GetDLCMeta(ctx, loanId)
@@ -125,3 +125,10 @@ func (k Keeper) GetRepaymentCetAdaptorPoint(ctx sdk.Context, loanId string) ([]b
 
 	return dlctypes.GetSignaturePointFromEvent(dlcEvent, types.RepaidOutcomeIndex)
 }
+
+// RepaymentCetSigned returns true if the repayment cet adaptor signatures already exist, false otherwise
+func (k Keeper) RepaymentCetSigned(ctx sdk.Context, loanId string) bool {
+	dlcMeta := k.GetDLCMeta(ctx, loanId)
+
+	return len(dlcMeta.RepaymentCet.DCMAdaptorSignatures) > 0
+}

x/lending/module/abci.go

@@ -86,8 +86,8 @@ func handlePendingLoans(ctx sdk.Context, k keeper.Keeper) error {
 				continue
 			}
 
-			// try to approve loan if all deposit txs verified
-			if k.DepositsVerified(ctx, k.GetAuthorization(ctx, loan.VaultAddress, authorizationId)) {
+			// try to approve loan if the repayment cet signed by DCM and all deposit txs verified
+			if k.RepaymentCetSigned(ctx, loan.VaultAddress) && k.DepositsVerified(ctx, k.GetAuthorization(ctx, loan.VaultAddress, authorizationId)) {
 				// check LTV
 				if !types.CheckLTV(loan.CollateralAmount, int(pool.Config.CollateralAsset.Decimals), loan.BorrowAmount.Amount, int(pool.Config.LendingAsset.Decimals), pool.Config.MaxLtv, currentPrice, pool.Config.CollateralAsset.IsBasePriceAsset) {
 					rejectHandler(loan, authorizationId, types.ErrInsufficientCollateral)
@@ -314,13 +314,10 @@ func handleRepayments(ctx sdk.Context, k keeper.Keeper) error {
 			continue
 		}
 
+		// get dlc meta
 		dlcMeta := k.GetDLCMeta(ctx, loan.VaultAddress)
 
-		// check if the DCM adaptor signatures have been submitted
-		if len(dlcMeta.RepaymentCet.DCMAdaptorSignatures) == 0 {
-			continue
-		}
-
+		// check if the DCM adapted signatures already exist
 		if len(dlcMeta.RepaymentCet.DCMAdaptedSignatures) == 0 {
 			// check if the event attestation has been submitted
 			attestation := k.DLCKeeper().GetAttestationByEvent(ctx, loan.DlcEventId)

x/lending/types/lending.go

@@ -235,6 +235,11 @@ func CheckBorrowAmountLimit(pool *LendingPool, borrowAmount sdkmath.Int) error {
 	return nil
 }
 
+// LoanDisbursed returns true if the loan has been disbursed, false otherwise
+func LoanDisbursed(loan *Loan) bool {
+	return loan.Status >= LoanStatus_Open
+}
+
 // CollateralRedeemable returns true if the collateral is redeemable, false otherwise
 func CollateralRedeemable(loan *Loan) bool {
 	if len(loan.Authorizations) > 0 {