let specialHandleFeeRate return the fee rate number and calls PostGas…

…Price in single spot

zetaclient/chains/bitcoin/observer/observer.go

@@ -342,33 +342,42 @@ func (ob *Observer) WatchGasPrice() {
 // PostGasPrice posts gas price to zetacore
 // TODO(revamp): move to gas price file
 func (ob *Observer) PostGasPrice() error {
+	var err error
+	feeRateEstimated := uint64(0)
+
 	// special handle regnet and testnet gas rate
 	if ob.Chain().NetworkType != chains.NetworkType_mainnet {
-		return ob.specialHandleFeeRate()
-	}
-
-	// EstimateSmartFee returns the fees per kilobyte (BTC/kb) targeting given block confirmation
-	feeResult, err := ob.btcClient.EstimateSmartFee(1, &btcjson.EstimateModeEconomical)
-	if err != nil {
-		return err
-	}
-	if feeResult.Errors != nil || feeResult.FeeRate == nil {
-		return fmt.Errorf("error getting gas price: %s", feeResult.Errors)
-	}
-	if *feeResult.FeeRate > math.MaxInt64 {
-		return fmt.Errorf("gas price is too large: %f", *feeResult.FeeRate)
+		feeRateEstimated, err = ob.specialHandleFeeRate()
+		if err != nil {
+			ob.logger.GasPrice.Err(err).Msg("error specialHandleFeeRate")
+			return err
+		}
+	} else {
+		// EstimateSmartFee returns the fees per kilobyte (BTC/kb) targeting given block confirmation
+		feeResult, err := ob.btcClient.EstimateSmartFee(1, &btcjson.EstimateModeEconomical)
+		if err != nil {
+			ob.logger.GasPrice.Err(err).Msg("error EstimateSmartFee")
+			return err
+		}
+		if feeResult.Errors != nil || feeResult.FeeRate == nil {
+			return fmt.Errorf("error getting gas price: %s", feeResult.Errors)
+		}
+		if *feeResult.FeeRate > math.MaxInt64 {
+			return fmt.Errorf("gas price is too large: %f", *feeResult.FeeRate)
+		}
+		feeRateEstimated = bitcoin.FeeRateToSatPerByte(*feeResult.FeeRate).Uint64()
 	}
-	feeRatePerByte := bitcoin.FeeRateToSatPerByte(*feeResult.FeeRate)
 
+	// query the current block number
 	blockNumber, err := ob.btcClient.GetBlockCount()
 	if err != nil {
 		return err
 	}
 
 	// #nosec G701 always positive
-	_, err = ob.ZetacoreClient().PostGasPrice(ob.Chain(), feeRatePerByte.Uint64(), "100", uint64(blockNumber))
+	_, err = ob.ZetacoreClient().PostGasPrice(ob.Chain(), feeRateEstimated, "100", uint64(blockNumber))
 	if err != nil {
-		ob.logger.GasPrice.Err(err).Msg("PostGasPrice:")
+		ob.logger.GasPrice.Err(err).Msg("err PostGasPrice")
 		return err
 	}
 
@@ -635,33 +644,20 @@ func (ob *Observer) LoadBroadcastedTxMap() error {
 }
 
 // specialHandleFeeRate handles the fee rate for regnet and testnet
-func (ob *Observer) specialHandleFeeRate() error {
-	blockNumber, err := ob.btcClient.GetBlockCount()
-	if err != nil {
-		return errors.Wrapf(err, "specialHandleFeeRate: error GetBlockCount")
-	}
-
-	feeRateEstimated := uint64(0)
+func (ob *Observer) specialHandleFeeRate() (uint64, error) {
 	switch ob.Chain().NetworkType {
 	case chains.NetworkType_privnet:
 		// hardcode gas price here since RPC 'EstimateSmartFee' is not available on regtest (privnet)
-		feeRateEstimated = 1
+		return 1, nil
 	case chains.NetworkType_testnet:
-		feeRateEstimated, err = rpc.GetRecentFeeRate(ob.btcClient, ob.netParams)
+		feeRateEstimated, err := rpc.GetRecentFeeRate(ob.btcClient, ob.netParams)
 		if err != nil {
-			return errors.Wrapf(err, "specialHandleFeeRate: error GetRecentFeeRate")
+			return 0, errors.Wrapf(err, "error GetRecentFeeRate")
 		}
+		return feeRateEstimated, nil
 	default:
-		return fmt.Errorf("specialHandleFeeRate: unsupported bitcoin network type %d", ob.Chain().NetworkType)
+		return 0, fmt.Errorf(" unsupported bitcoin network type %d", ob.Chain().NetworkType)
 	}
-
-	// #nosec G701 always in range
-	_, err = ob.ZetacoreClient().PostGasPrice(ob.Chain(), feeRateEstimated, "100", uint64(blockNumber))
-	if err != nil {
-		return errors.Wrapf(err, "specialHandleFeeRate: error PostGasPrice")
-	}
-
-	return nil
 }
 
 // isTssTransaction checks if a given transaction was sent by TSS itself.

zetaclient/chains/bitcoin/rpc/rpc.go

@@ -119,6 +119,7 @@ func GetRawTxResult(
 }
 
 // GetRecentFeeRate gets the highest fee rate from recent blocks
+// Note: this method is only used for testnet
 func GetRecentFeeRate(rpcClient interfaces.BTCRPCClient, netParams *chaincfg.Params) (uint64, error) {
 	blockNumber, err := rpcClient.GetBlockCount()
 	if err != nil {
@@ -148,7 +149,7 @@ func GetRecentFeeRate(rpcClient interfaces.BTCRPCClient, netParams *chaincfg.Par
 		}
 	}
 
-	// use 10 sat/byte as default estimation when fee rate is 0
+	// use 10 sat/byte as default estimation if recent fee rate drops to 0
 	if highestRate == 0 {
 		highestRate = defaultTestnetFeeRate
 	}