fetch fee rates from configurable external sources

src/main/java/com/sparrowwallet/sparrow/AppController.java

@@ -1495,6 +1495,15 @@ public class AppController implements Initializable {
         selectedToggle.ifPresent(toggle -> bitcoinUnit.selectToggle(toggle));
     }
 
+    @Subscribe
+    public void feeRateSourceChanged(FeeRatesSourceChangedEvent event) {
+        ElectrumServer.FeeRatesService feeRatesService = new ElectrumServer.FeeRatesService();
+        feeRatesService.setOnSucceeded(workerStateEvent -> {
+            EventManager.get().post(feeRatesService.getValue());
+        });
+        feeRatesService.start();
+    }
+
     @Subscribe
     public void fiatCurrencySelected(FiatCurrencySelectedEvent event) {
         ratesService.cancel();

src/main/java/com/sparrowwallet/sparrow/event/FeeRateSelectionChangedEvent.java

@@ -1,15 +0,0 @@
-package com.sparrowwallet.sparrow.event;
-
-import com.sparrowwallet.sparrow.wallet.FeeRateSelection;
-
-public class FeeRateSelectionChangedEvent {
-    private final FeeRateSelection feeRateSelection;
-
-    public FeeRateSelectionChangedEvent(FeeRateSelection feeRateSelection) {
-        this.feeRateSelection = feeRateSelection;
-    }
-
-    public FeeRateSelection getFeeRateSelection() {
-        return feeRateSelection;
-    }
-}

src/main/java/com/sparrowwallet/sparrow/event/FeeRatesSelectionChangedEvent.java

@@ -0,0 +1,15 @@
+package com.sparrowwallet.sparrow.event;
+
+import com.sparrowwallet.sparrow.wallet.FeeRatesSelection;
+
+public class FeeRatesSelectionChangedEvent {
+    private final FeeRatesSelection feeRatesSelection;
+
+    public FeeRatesSelectionChangedEvent(FeeRatesSelection feeRatesSelection) {
+        this.feeRatesSelection = feeRatesSelection;
+    }
+
+    public FeeRatesSelection getFeeRateSelection() {
+        return feeRatesSelection;
+    }
+}

src/main/java/com/sparrowwallet/sparrow/event/FeeRatesSourceChangedEvent.java

@@ -0,0 +1,15 @@
+package com.sparrowwallet.sparrow.event;
+
+import com.sparrowwallet.sparrow.net.FeeRatesSource;
+
+public class FeeRatesSourceChangedEvent {
+    private final FeeRatesSource feeRatesSource;
+
+    public FeeRatesSourceChangedEvent(FeeRatesSource feeRatesSource) {
+        this.feeRatesSource = feeRatesSource;
+    }
+
+    public FeeRatesSource getFeeRateSource() {
+        return feeRatesSource;
+    }
+}

src/main/java/com/sparrowwallet/sparrow/io/Config.java

@@ -5,7 +5,8 @@ import com.sparrowwallet.drongo.BitcoinUnit;
 import com.sparrowwallet.sparrow.Mode;
 import com.sparrowwallet.sparrow.Theme;
 import com.sparrowwallet.sparrow.net.ExchangeSource;
-import com.sparrowwallet.sparrow.wallet.FeeRateSelection;
+import com.sparrowwallet.sparrow.net.FeeRatesSource;
+import com.sparrowwallet.sparrow.wallet.FeeRatesSelection;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -21,7 +22,8 @@ public class Config {
 
     private Mode mode;
     private BitcoinUnit bitcoinUnit;
-    private FeeRateSelection feeRateSelection;
+    private FeeRatesSource feeRatesSource;
+    private FeeRatesSelection feeRatesSelection;
     private Currency fiatCurrency;
     private ExchangeSource exchangeSource;
     private boolean groupByAddress = true;
@@ -101,12 +103,21 @@ public class Config {
         flush();
     }
 
-    public FeeRateSelection getFeeRateSelection() {
+    public FeeRatesSource getFeeRatesSource() {
-        return feeRateSelection;
+        return feeRatesSource;
     }
 
-    public void setFeeRateSelection(FeeRateSelection feeRateSelection) {
+    public void setFeeRatesSource(FeeRatesSource feeRatesSource) {
-        this.feeRateSelection = feeRateSelection;
+        this.feeRatesSource = feeRatesSource;
+        flush();
+    }
+
+    public FeeRatesSelection getFeeRatesSelection() {
+        return feeRatesSelection;
+    }
+
+    public void setFeeRatesSelection(FeeRatesSelection feeRatesSelection) {
+        this.feeRatesSelection = feeRatesSelection;
         flush();
     }
 

src/main/java/com/sparrowwallet/sparrow/net/ElectrumServer.java

@@ -604,6 +604,11 @@ public class ElectrumServer {
                 targetBlocksFeeRatesSats.put(target, minFeeRateSatsKb / 1000d);
             }
 
+            FeeRatesSource feeRatesSource = Config.get().getFeeRatesSource();
+            if(feeRatesSource != null) {
+                targetBlocksFeeRatesSats.putAll(feeRatesSource.getBlockTargetFeeRates(targetBlocksFeeRatesSats));
+            }
+
             return targetBlocksFeeRatesSats;
         } catch(ElectrumServerRpcException e) {
             throw new ServerException(e.getMessage(), e);
@@ -718,7 +723,7 @@ public class ElectrumServer {
     }
 
     public static class ConnectionService extends ScheduledService<FeeRatesUpdatedEvent> implements Thread.UncaughtExceptionHandler {
-        private static final int FEE_RATES_PERIOD = 1 * 60 * 1000;
+        private static final int FEE_RATES_PERIOD = 30 * 1000;
 
         private final boolean subscribe;
         private boolean firstCall = true;
@@ -1014,4 +1019,18 @@ public class ElectrumServer {
             };
         }
     }
+
+    public static class FeeRatesService extends Service<FeeRatesUpdatedEvent> {
+        @Override
+        protected Task<FeeRatesUpdatedEvent> createTask() {
+            return new Task<>() {
+                protected FeeRatesUpdatedEvent call() throws ServerException {
+                    ElectrumServer electrumServer = new ElectrumServer();
+                    Map<Integer, Double> blockTargetFeeRates = electrumServer.getFeeEstimates(SendController.TARGET_BLOCKS_RANGE);
+                    Set<MempoolRateSize> mempoolRateSizes = electrumServer.getMempoolRateSizes();
+                    return new FeeRatesUpdatedEvent(blockTargetFeeRates, mempoolRateSizes);
+                }
+            };
+        }
+    }
 }

src/main/java/com/sparrowwallet/sparrow/net/FeeRatesSource.java

@@ -0,0 +1,102 @@
+package com.sparrowwallet.sparrow.net;
+
+import com.google.common.net.HostAndPort;
+import com.google.gson.Gson;
+import com.sparrowwallet.sparrow.io.Config;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.io.Reader;
+import java.net.InetSocketAddress;
+import java.net.Proxy;
+import java.net.URL;
+import java.nio.charset.StandardCharsets;
+import java.util.Collections;
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+public enum FeeRatesSource {
+    ELECTRUM_SERVER("Electrum Server") {
+        @Override
+        public Map<Integer, Double> getBlockTargetFeeRates(Map<Integer, Double> defaultblockTargetFeeRates) {
+            return Collections.emptyMap();
+        }
+    },
+    MEMPOOL_SPACE("mempool.space") {
+        @Override
+        public Map<Integer, Double> getBlockTargetFeeRates(Map<Integer, Double> defaultblockTargetFeeRates) {
+            String url = "https://mempool.space/api/v1/fees/recommended";
+            return getThreeTierFeeRates(defaultblockTargetFeeRates, url);
+        }
+    },
+    BITCOINFEES_EARN_COM("bitcoinfees.earn.com") {
+        @Override
+        public Map<Integer, Double> getBlockTargetFeeRates(Map<Integer, Double> defaultblockTargetFeeRates) {
+            String url = "https://bitcoinfees.earn.com/api/v1/fees/recommended";
+            return getThreeTierFeeRates(defaultblockTargetFeeRates, url);
+        }
+    };
+
+    private static final Logger log = LoggerFactory.getLogger(FeeRatesSource.class);
+
+    private final String name;
+
+    FeeRatesSource(String name) {
+        this.name = name;
+    }
+
+    public abstract Map<Integer, Double> getBlockTargetFeeRates(Map<Integer, Double> defaultblockTargetFeeRates);
+
+    public String getName() {
+        return name;
+    }
+
+    private static Map<Integer, Double> getThreeTierFeeRates(Map<Integer, Double> defaultblockTargetFeeRates, String url) {
+        Proxy proxy = getProxy();
+
+        Map<Integer, Double> blockTargetFeeRates = new LinkedHashMap<>();
+        try(InputStream is = (proxy == null ? new URL(url).openStream() : new URL(url).openConnection(proxy).getInputStream()); Reader reader = new InputStreamReader(is, StandardCharsets.UTF_8)) {
+            Gson gson = new Gson();
+            ThreeTierRates threeTierRates = gson.fromJson(reader, ThreeTierRates.class);
+            for(Integer blockTarget : defaultblockTargetFeeRates.keySet()) {
+                if(blockTarget < 3) {
+                    blockTargetFeeRates.put(blockTarget, threeTierRates.fastestFee);
+                } else if(blockTarget < 6) {
+                    blockTargetFeeRates.put(blockTarget, threeTierRates.halfHourFee);
+                } else if(blockTarget <= 10 || defaultblockTargetFeeRates.get(blockTarget) > threeTierRates.hourFee) {
+                    blockTargetFeeRates.put(blockTarget, threeTierRates.hourFee);
+                } else {
+                    blockTargetFeeRates.put(blockTarget, defaultblockTargetFeeRates.get(blockTarget));
+                }
+            }
+        } catch (Exception e) {
+            log.warn("Error retrieving recommended fee rates from " + url, e);
+        }
+
+        return blockTargetFeeRates;
+    }
+
+    private static Proxy getProxy() {
+        Config config = Config.get();
+        if(config.isUseProxy()) {
+            HostAndPort proxy = HostAndPort.fromString(config.getProxyServer());
+            InetSocketAddress proxyAddress = new InetSocketAddress(proxy.getHost(), proxy.getPortOrDefault(ProxyTcpOverTlsTransport.DEFAULT_PROXY_PORT));
+            return new Proxy(Proxy.Type.SOCKS, proxyAddress);
+        }
+
+        return null;
+    }
+
+    @Override
+    public String toString() {
+        return name;
+    }
+
+    private static class ThreeTierRates {
+        Double fastestFee;
+        Double halfHourFee;
+        Double hourFee;
+    }
+}

src/main/java/com/sparrowwallet/sparrow/preferences/GeneralPreferencesController.java

@@ -3,13 +3,10 @@ package com.sparrowwallet.sparrow.preferences;
 import com.sparrowwallet.drongo.BitcoinUnit;
 import com.sparrowwallet.sparrow.EventManager;
 import com.sparrowwallet.sparrow.control.UnlabeledToggleSwitch;
-import com.sparrowwallet.sparrow.event.BitcoinUnitChangedEvent;
+import com.sparrowwallet.sparrow.event.*;
-import com.sparrowwallet.sparrow.event.FeeRateSelectionChangedEvent;
-import com.sparrowwallet.sparrow.event.FiatCurrencySelectedEvent;
-import com.sparrowwallet.sparrow.event.VersionCheckStatusEvent;
 import com.sparrowwallet.sparrow.io.Config;
 import com.sparrowwallet.sparrow.net.ExchangeSource;
-import com.sparrowwallet.sparrow.wallet.FeeRateSelection;
+import com.sparrowwallet.sparrow.net.FeeRatesSource;
 import javafx.beans.value.ChangeListener;
 import javafx.beans.value.ObservableValue;
 import javafx.fxml.FXML;
@@ -27,7 +24,7 @@ public class GeneralPreferencesController extends PreferencesDetailController {
     private ComboBox<BitcoinUnit> bitcoinUnit;
 
     @FXML
-    private ComboBox<FeeRateSelection> feeRateSelection;
+    private ComboBox<FeeRatesSource> feeRatesSource;
 
     @FXML
     private ComboBox<Currency> fiatCurrency;
@@ -68,16 +65,16 @@ public class GeneralPreferencesController extends PreferencesDetailController {
             EventManager.get().post(new BitcoinUnitChangedEvent(newValue));
         });
 
-        if(config.getFeeRateSelection() != null) {
+        if(config.getFeeRatesSource() != null) {
-            feeRateSelection.setValue(config.getFeeRateSelection());
+            feeRatesSource.setValue(config.getFeeRatesSource());
         } else {
-            feeRateSelection.getSelectionModel().select(0);
+            feeRatesSource.getSelectionModel().select(1);
-            config.setFeeRateSelection(FeeRateSelection.BLOCK_TARGET);
+            config.setFeeRatesSource(feeRatesSource.getValue());
         }
 
-        feeRateSelection.valueProperty().addListener((observable, oldValue, newValue) -> {
+        feeRatesSource.valueProperty().addListener((observable, oldValue, newValue) -> {
-            config.setFeeRateSelection(newValue);
+            config.setFeeRatesSource(newValue);
-            EventManager.get().post(new FeeRateSelectionChangedEvent(newValue));
+            EventManager.get().post(new FeeRatesSourceChangedEvent(newValue));
         });
 
         if(config.getExchangeSource() != null) {

src/main/java/com/sparrowwallet/sparrow/wallet/FeeRatesSelection.java

@@ -1,11 +1,11 @@
 package com.sparrowwallet.sparrow.wallet;
 
-public enum FeeRateSelection {
+public enum FeeRatesSelection {
     BLOCK_TARGET("Block Target"), MEMPOOL_SIZE("Mempool Size");
 
     private final String name;
 
-    private FeeRateSelection(String name) {
+    private FeeRatesSelection(String name) {
         this.name = name;
     }
 

src/main/java/com/sparrowwallet/sparrow/wallet/SendController.java

@@ -269,13 +269,14 @@ public class SendController extends WalletFormController implements Initializabl
             mempoolSizeFeeRatesChart.update(mempoolHistogram);
         }
 
-        FeeRateSelection feeRateSelection = Config.get().getFeeRateSelection();
+        FeeRatesSelection feeRatesSelection = Config.get().getFeeRatesSelection();
-        updateFeeRateSelection(feeRateSelection);
+        feeRatesSelection = (feeRatesSelection == null ? FeeRatesSelection.BLOCK_TARGET : feeRatesSelection);
-        feeSelectionToggleGroup.selectToggle(feeRateSelection == FeeRateSelection.BLOCK_TARGET ? targetBlocksToggle : mempoolSizeToggle);
+        updateFeeRateSelection(feeRatesSelection);
+        feeSelectionToggleGroup.selectToggle(feeRatesSelection == FeeRatesSelection.BLOCK_TARGET ? targetBlocksToggle : mempoolSizeToggle);
         feeSelectionToggleGroup.selectedToggleProperty().addListener((observable, oldValue, newValue) -> {
-            FeeRateSelection newFeeRateSelection = (FeeRateSelection)newValue.getUserData();
+            FeeRatesSelection newFeeRatesSelection = (FeeRatesSelection)newValue.getUserData();
-            Config.get().setFeeRateSelection(newFeeRateSelection);
+            Config.get().setFeeRatesSelection(newFeeRatesSelection);
-            EventManager.get().post(new FeeRateSelectionChangedEvent(newFeeRateSelection));
+            EventManager.get().post(new FeeRatesSelectionChangedEvent(newFeeRatesSelection));
         });
 
         fee.setTextFormatter(new CoinTextFormatter());
@@ -472,8 +473,8 @@ public class SendController extends WalletFormController implements Initializabl
         return Collections.emptyList();
     }
 
-    private void updateFeeRateSelection(FeeRateSelection feeRateSelection) {
+    private void updateFeeRateSelection(FeeRatesSelection feeRatesSelection) {
-        boolean blockTargetSelection = (feeRateSelection == FeeRateSelection.BLOCK_TARGET);
+        boolean blockTargetSelection = (feeRatesSelection == FeeRatesSelection.BLOCK_TARGET);
         targetBlocksField.setVisible(blockTargetSelection);
         blockTargetFeeRatesChart.setVisible(blockTargetSelection);
         setDefaultFeeRate();
@@ -481,14 +482,15 @@ public class SendController extends WalletFormController implements Initializabl
     }
 
     private void setDefaultFeeRate() {
+        int defaultTarget = TARGET_BLOCKS_RANGE.get((TARGET_BLOCKS_RANGE.size() / 2) - 1);
+        int index = TARGET_BLOCKS_RANGE.indexOf(defaultTarget);
+        Double defaultRate = getTargetBlocksFeeRates().get(defaultTarget);
         if(targetBlocksField.isVisible()) {
-            int defaultTarget = TARGET_BLOCKS_RANGE.get((TARGET_BLOCKS_RANGE.size() / 2) - 1);
-            int index = TARGET_BLOCKS_RANGE.indexOf(defaultTarget);
             targetBlocks.setValue(index);
             blockTargetFeeRatesChart.select(defaultTarget);
-            setFeeRate(getTargetBlocksFeeRates().get(getTargetBlocks()));
+            setFeeRate(defaultRate);
         } else {
-            feeRange.setValue(5.0);
+            feeRange.setValue(Math.log(defaultRate) / Math.log(2));
             setFeeRate(getFeeRangeRate());
         }
     }
@@ -771,7 +773,7 @@ public class SendController extends WalletFormController implements Initializabl
     }
 
     @Subscribe
-    public void feeRateSelectionChanged(FeeRateSelectionChangedEvent event) {
+    public void feeRateSelectionChanged(FeeRatesSelectionChangedEvent event) {
         updateFeeRateSelection(event.getFeeRateSelection());
     }
 

src/main/resources/com/sparrowwallet/sparrow/preferences/general.fxml

@@ -15,7 +15,7 @@
 <?import com.sparrowwallet.sparrow.net.ExchangeSource?>
 <?import com.sparrowwallet.sparrow.control.UnlabeledToggleSwitch?>
 <?import com.sparrowwallet.sparrow.control.HelpLabel?>
-<?import com.sparrowwallet.sparrow.wallet.FeeRateSelection?>
+<?import com.sparrowwallet.sparrow.net.FeeRatesSource?>
 
 <GridPane hgap="10.0" vgap="10.0" stylesheets="@preferences.css, @../general.css" xmlns="http://javafx.com/javafx/10.0.2-internal" xmlns:fx="http://javafx.com/fxml/1" fx:controller="com.sparrowwallet.sparrow.preferences.GeneralPreferencesController">
     <padding>
@@ -42,16 +42,17 @@
                 </ComboBox>
                 <HelpLabel helpText="Display unit for bitcoin amounts.\nAuto displays amounts over 1 BTC in BTC, and amounts under that in satoshis."/>
             </Field>
-            <Field text="Fee rate selection:">
+            <Field text="Fee rates source:">
-                <ComboBox fx:id="feeRateSelection">
+                <ComboBox fx:id="feeRatesSource">
                     <items>
                         <FXCollections fx:factory="observableArrayList">
-                            <FeeRateSelection fx:constant="BLOCK_TARGET" />
+                            <FeeRatesSource fx:constant="ELECTRUM_SERVER" />
-                            <FeeRateSelection fx:constant="MEMPOOL_SIZE" />
+                            <FeeRatesSource fx:constant="MEMPOOL_SPACE" />
+                            <FeeRatesSource fx:constant="BITCOINFEES_EARN_COM" />
                         </FXCollections>
                     </items>
                 </ComboBox>
-                <HelpLabel helpText="Fee rate selection can be done either by estimating the number of blocks until a transaction is mined, or examining the current size of the mempool."/>
+                <HelpLabel helpText="Recommended fee rates can be sourced from your connected Electrum server, or an external source."/>
             </Field>
         </Fieldset>
         <Fieldset inputGrow="SOMETIMES" text="Fiat" styleClass="wideLabelFieldSet">

src/main/resources/com/sparrowwallet/sparrow/wallet/send.fxml

@@ -23,7 +23,7 @@
 <?import org.controlsfx.glyphfont.Glyph?>
 <?import com.sparrowwallet.sparrow.control.MempoolSizeFeeRatesChart?>
 <?import org.controlsfx.control.SegmentedButton?>
-<?import com.sparrowwallet.sparrow.wallet.FeeRateSelection?>
+<?import com.sparrowwallet.sparrow.wallet.FeeRatesSelection?>
 
 <BorderPane stylesheets="@send.css, @wallet.css, @../script.css, @../general.css" styleClass="wallet-pane" xmlns="http://javafx.com/javafx/10.0.2-internal" xmlns:fx="http://javafx.com/fxml/1" fx:controller="com.sparrowwallet.sparrow.wallet.SendController">
     <center>
@@ -67,7 +67,7 @@
                                     <Tooltip text="Determine fee via estimated number of blocks"/>
                                 </tooltip>
                                 <userData>
-                                    <FeeRateSelection fx:constant="BLOCK_TARGET"/>
+                                    <FeeRatesSelection fx:constant="BLOCK_TARGET"/>
                                 </userData>
                             </ToggleButton>
                             <ToggleButton fx:id="mempoolSizeToggle" text="Mempool Size" toggleGroup="$feeSelectionToggleGroup">
@@ -75,7 +75,7 @@
                                     <Tooltip text="Determine fee via current mempool size"/>
                                 </tooltip>
                                 <userData>
-                                    <FeeRateSelection fx:constant="MEMPOOL_SIZE"/>
+                                    <FeeRatesSelection fx:constant="MEMPOOL_SIZE"/>
                                 </userData>
                             </ToggleButton>
                         </buttons>