Configure a maximum airdrop USD value

Author: jeffyanta

pkg/code/server/transaction/airdrop.go

@@ -248,6 +248,12 @@ func (s *transactionServer) airdrop(ctx context.Context, intentId string, owner
 	coreMintAmount := nativeAmount / otherRateRecord.Rate
 	quarkAmount := uint64(coreMintAmount * float64(common.CoreMintQuarksPerUnit))
 
+	usdValue := usdRateRecord.Rate * coreMintAmount
+	if usdValue > s.conf.maxAirdropUsdValue.Get(ctx) {
+		log.Warn("airdrop exceeds max usd value")
+		return nil, ErrIneligibleForAirdrop
+	}
+
 	var isAirdropperManuallyUnlocked bool
 	s.airdropperLock.Lock()
 	defer func() {
@@ -318,7 +324,7 @@ func (s *transactionServer) airdrop(ctx context.Context, intentId string, owner
 			ExchangeCurrency: currencyCode,
 			ExchangeRate:     otherRateRecord.Rate,
 			NativeAmount:     nativeAmount,
-			UsdMarketValue:   usdRateRecord.Rate * coreMintAmount,
+			UsdMarketValue:   usdValue,
 
 			IsWithdrawal: false,
 		},

pkg/code/server/transaction/config.go

@@ -33,6 +33,9 @@ const (
 	AirdropperOwnerPublicKeyEnvName = envConfigPrefix + "AIRDROPPER_OWNER_PUBLIC_KEY"
 	defaultAirdropperOwnerPublicKey = "invalid" // Ensure something valid is set
 
+	MaxAirdropUsdValueEnvName = envConfigPrefix + "_MAX_AIRDROP_USD_VALUE"
+	defaultMaxAirdropUsdValue = 1.0
+
 	SwapSubsidizerOwnerPublicKeyEnvName = envConfigPrefix + "SWAP_SUBSIDIZER_OWNER_PUBLIC_KEY"
 	defaultSwapSubsidizerOwnerPublicKey = "invalid" // Ensure something valid is set
 
@@ -52,8 +55,8 @@ type conf struct {
 	clientReceiveTimeout         config.Duration
 	feeCollectorTokenPublicKey   config.String
 	enableAirdrops               config.Bool
-	enableAsyncAirdropProcessing config.Bool
 	airdropperOwnerPublicKey     config.String
+	maxAirdropUsdValue           config.Float64
 	swapSubsidizerOwnerPublicKey config.String
 	swapTimeout                  config.Duration
 	swapPriorityFeeMultiple      config.Float64
@@ -75,8 +78,8 @@ func WithEnvConfigs() ConfigProvider {
 			clientReceiveTimeout:         env.NewDurationConfig(ClientReceiveTimeoutConfigEnvName, defaultClientReceiveTimeout),
 			feeCollectorTokenPublicKey:   env.NewStringConfig(FeeCollectorTokenPublicKeyConfigEnvName, defaultFeeCollectorPublicKey),
 			enableAirdrops:               env.NewBoolConfig(EnableAirdropsConfigEnvName, defaultEnableAirdrops),
-			enableAsyncAirdropProcessing: wrapper.NewBoolConfig(memory.NewConfig(true), true),
 			airdropperOwnerPublicKey:     env.NewStringConfig(AirdropperOwnerPublicKeyEnvName, defaultAirdropperOwnerPublicKey),
+			maxAirdropUsdValue:           env.NewFloat64Config(MaxAirdropUsdValueEnvName, defaultMaxAirdropUsdValue),
 			swapSubsidizerOwnerPublicKey: env.NewStringConfig(SwapSubsidizerOwnerPublicKeyEnvName, defaultSwapSubsidizerOwnerPublicKey),
 			swapTimeout:                  env.NewDurationConfig(SwapTimeoutConfigEnvName, defaultSwapTimeout),
 			swapPriorityFeeMultiple:      env.NewFloat64Config(SwapPriorityFeeMultiple, defaultSwapPriorityFeeMultiple),
@@ -105,8 +108,8 @@ func withManualTestOverrides(overrides *testOverrides) ConfigProvider {
 			clientReceiveTimeout:         wrapper.NewDurationConfig(memory.NewConfig(overrides.clientReceiveTimeout), defaultClientReceiveTimeout),
 			feeCollectorTokenPublicKey:   wrapper.NewStringConfig(memory.NewConfig(overrides.feeCollectorTokenPublicKey), defaultFeeCollectorPublicKey),
 			enableAirdrops:               wrapper.NewBoolConfig(memory.NewConfig(overrides.enableAirdrops), false),
-			enableAsyncAirdropProcessing: wrapper.NewBoolConfig(memory.NewConfig(false), false),
 			airdropperOwnerPublicKey:     wrapper.NewStringConfig(memory.NewConfig(defaultAirdropperOwnerPublicKey), defaultAirdropperOwnerPublicKey),
+			maxAirdropUsdValue:           wrapper.NewFloat64Config(memory.NewConfig(defaultMaxAirdropUsdValue), defaultMaxAirdropUsdValue),
 			swapSubsidizerOwnerPublicKey: wrapper.NewStringConfig(memory.NewConfig(defaultSwapSubsidizerOwnerPublicKey), defaultSwapSubsidizerOwnerPublicKey),
 			swapTimeout:                  wrapper.NewDurationConfig(memory.NewConfig(defaultSwapTimeout), defaultSwapTimeout),
 			swapPriorityFeeMultiple:      wrapper.NewFloat64Config(memory.NewConfig(defaultSwapPriorityFeeMultiple), defaultSwapPriorityFeeMultiple),