add mempool.bisq.services as a broadcaster, broadcast tx twice if possible on mainnet, handle different network broadcaster network capabilities

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

@@ -15,6 +15,7 @@ import java.net.Proxy;
 import java.net.URL;
 import java.nio.charset.StandardCharsets;
 import java.security.SecureRandom;
+import java.util.List;
 
 public enum BroadcastSource {
     BLOCKSTREAM_INFO("blockstream.info", "https://blockstream.info", "http://explorerzydxu5ecjrkwceayqybizmpjjznk5izmitf2modhcusuqlid.onion") {
@@ -24,6 +25,11 @@ public enum BroadcastSource {
             return postTransactionData(data);
         }
 
+        @Override
+        public List<Network> getSupportedNetworks() {
+            return List.of(Network.MAINNET, Network.TESTNET);
+        }
+
         protected URL getURL(Proxy proxy) throws MalformedURLException {
             if(Network.get() == Network.MAINNET) {
                 return new URL(getBaseUrl(proxy) + "/api/tx");
@@ -40,6 +46,11 @@ public enum BroadcastSource {
             return postTransactionData(data);
         }
 
+        @Override
+        public List<Network> getSupportedNetworks() {
+            return List.of(Network.MAINNET, Network.TESTNET, Network.SIGNET);
+        }
+
         protected URL getURL(Proxy proxy) throws MalformedURLException {
             if(Network.get() == Network.MAINNET) {
                 return new URL(getBaseUrl(proxy) + "/api/tx");
@@ -56,6 +67,32 @@ public enum BroadcastSource {
             return postTransactionData(data);
         }
 
+        @Override
+        public List<Network> getSupportedNetworks() {
+            return List.of(Network.MAINNET);
+        }
+
+        protected URL getURL(Proxy proxy) throws MalformedURLException {
+            if(Network.get() == Network.MAINNET) {
+                return new URL(getBaseUrl(proxy) + "/api/tx");
+            } else if(Network.get() == Network.TESTNET) {
+                return new URL(getBaseUrl(proxy) + "/testnet/api/tx");
+            } else {
+                throw new IllegalStateException("Cannot broadcast transaction to " + getName() + " on network " + Network.get());
+            }
+        }
+    },
+    MEMPOOL_BISQ_SERVICES("mempool.bisq.services", "https://mempool.bisq.services", "http://mempoolcutehjtynu4k4rd746acmssvj2vz4jbz4setb72clbpx2dfqd.onion") {
+        public Sha256Hash broadcastTransaction(Transaction transaction) throws BroadcastException {
+            String data = Utils.bytesToHex(transaction.bitcoinSerialize());
+            return postTransactionData(data);
+        }
+
+        @Override
+        public List<Network> getSupportedNetworks() {
+            return List.of(Network.MAINNET);
+        }
+
         protected URL getURL(Proxy proxy) throws MalformedURLException {
             if(Network.get() == Network.MAINNET) {
                 return new URL(getBaseUrl(proxy) + "/api/tx");
@@ -98,6 +135,8 @@ public enum BroadcastSource {
 
     public abstract Sha256Hash broadcastTransaction(Transaction transaction) throws BroadcastException;
 
+    public abstract List<Network> getSupportedNetworks();
+
     protected abstract URL getURL(Proxy proxy) throws MalformedURLException;
 
     public Sha256Hash postTransactionData(String data) throws BroadcastException {

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

@@ -37,6 +37,8 @@ public class ElectrumServer {
 
     private static final String[] SUPPORTED_VERSIONS = new String[]{"1.3", "1.4.2"};
 
+    private static final int MINIMUM_BROADCASTS = 2;
+
     public static final BlockTransaction UNFETCHABLE_BLOCK_TRANSACTION = new BlockTransaction(Sha256Hash.ZERO_HASH, 0, null, null, null);
 
     private static Transport transport;
@@ -1295,15 +1297,23 @@ public class ElectrumServer {
                 protected Sha256Hash call() throws ServerException {
                     //If Tor proxy is configured, try all external broadcast sources in random order before falling back to connected Electrum server
                     if(AppServices.getProxy() != null) {
-                        List<BroadcastSource> broadcastSources = new ArrayList<>(Arrays.asList(BroadcastSource.values()));
+                        List<BroadcastSource> broadcastSources = Arrays.stream(BroadcastSource.values()).filter(src -> src.getSupportedNetworks().contains(Network.get())).collect(Collectors.toList());
-                        while(!broadcastSources.isEmpty()) {
+                        Sha256Hash txid = null;
+                        for(int i = 1; !broadcastSources.isEmpty(); i++) {
                             try {
                                 BroadcastSource broadcastSource = broadcastSources.remove(new Random().nextInt(broadcastSources.size()));
-                                return broadcastSource.broadcastTransaction(transaction);
+                                txid = broadcastSource.broadcastTransaction(transaction);
+                                if(Network.get() != Network.MAINNET || i >= MINIMUM_BROADCASTS || broadcastSources.isEmpty()) {
+                                    return txid;
+                                }
                             } catch(BroadcastSource.BroadcastException e) {
                                 //ignore, already logged
                             }
                         }
+
+                        if(txid != null) {
+                            return txid;
+                        }
                     }
 
                     ElectrumServer electrumServer = new ElectrumServer();