_ Git - ldk-java/blob - src/main/java/org/ldk/batteries/ChannelManagerConstructor.java

   1 package org.ldk.batteries;
   2
   3 import javax.annotation.Nullable;
   4 import org.ldk.enums.Network;
   5 import org.ldk.structs.*;
   6 import org.ldk.util.TwoTuple;
   7
   8 import java.io.IOException;
   9
  10
  11 /**
  12  * A simple utility class which assists in constructing a fresh or deserializing from disk a ChannelManager and one or
  13  * more ChannelMonitors.
  14  *
  15  * Also constructs a PeerManager and spawns a background thread to monitor for and notify you of relevant Events.
  16  */
  17 public class ChannelManagerConstructor {
  18     /**
  19      * An Exception that indicates the serialized data is invalid and has been corrupted on disk. You should attempt to
  20      * restore from a backup if there is one which is known to be current. Otherwise, funds may have been lost.
  21      */
  22     public static class InvalidSerializedDataException extends Exception {}
  23
  24     /**
  25      * The ChannelManager either deserialized or newly-constructed.
  26      */
  27     public final ChannelManager channel_manager;
  28     /**
  29      * The latest block has the channel manager saw. If this is non-null it is a 32-byte block hash.
  30      * You should sync the blockchain starting with the block that builds on this block.
  31      */
  32     public final byte[] channel_manager_latest_block_hash;
  33     /**
  34      * A list of ChannelMonitors and the last block they each saw. You should sync the blockchain on each individually
  35      * starting with the block that builds on the hash given.
  36      * After doing so (and syncing the blockchain on the channel manager as well), you should call chain_sync_completed()
  37      * and then continue to normal application operation.
  38      */
  39     public final TwoTuple_BlockHashChannelMonitorZ[] channel_monitors;
  40     /**
  41      * A PeerManager which is constructed to pass messages and handle connections to peers.
  42      */
  43     public final PeerManager peer_manager;
  44     /**
  45      * A NioPeerHandler which manages a background thread to handle socket events and pass them to the peer_manager.
  46      */
  47     public final NioPeerHandler nio_peer_handler;
  48     /**
  49      * If a `NetworkGraph` is provided to the constructor *and* a `LockableScore` is provided to
  50          * `chain_sync_completed`, this will be non-null after `chain_sync_completed` returns.
  51          *
  52      * It should be used to send payments instead of doing so directly via the `channel_manager`.
  53          *
  54      * When payments are made through this, they are automatically retried and the provided Scorer
  55      * will be updated with payment failure data.
  56      */
  57     @Nullable public InvoicePayer payer;
  58
  59     private final ChainMonitor chain_monitor;
  60     @Nullable private final NetworkGraph net_graph;
  61     @Nullable private final NetGraphMsgHandler graph_msg_handler;
  62     private final Logger logger;
  63
  64     /**
  65      * Deserializes a channel manager and a set of channel monitors from the given serialized copies and interface implementations
  66      *
  67      * @param filter If provided, the outputs which were previously registered to be monitored for will be loaded into the filter.
  68      *               Note that if the provided Watch is a ChainWatch and has an associated filter, the previously registered
  69      *               outputs will be loaded when chain_sync_completed is called.
  70      */
  71     public ChannelManagerConstructor(byte[] channel_manager_serialized, byte[][] channel_monitors_serialized,
  72                                      KeysInterface keys_interface, FeeEstimator fee_estimator, ChainMonitor chain_monitor, @Nullable Filter filter,
  73                                      @Nullable NetworkGraph net_graph,
  74                                      BroadcasterInterface tx_broadcaster, Logger logger) throws InvalidSerializedDataException {
  75         final IgnoringMessageHandler no_custom_messages = IgnoringMessageHandler.of();
  76         final ChannelMonitor[] monitors = new ChannelMonitor[channel_monitors_serialized.length];
  77         this.channel_monitors = new TwoTuple_BlockHashChannelMonitorZ[monitors.length];
  78         for (int i = 0; i < monitors.length; i++) {
  79             Result_C2Tuple_BlockHashChannelMonitorZDecodeErrorZ res = UtilMethods.C2Tuple_BlockHashChannelMonitorZ_read(channel_monitors_serialized[i], keys_interface);
  80             if (res instanceof Result_C2Tuple_BlockHashChannelMonitorZDecodeErrorZ.Result_C2Tuple_BlockHashChannelMonitorZDecodeErrorZ_Err) {
  81                 throw new InvalidSerializedDataException();
  82             }
  83             byte[] block_hash = ((Result_C2Tuple_BlockHashChannelMonitorZDecodeErrorZ.Result_C2Tuple_BlockHashChannelMonitorZDecodeErrorZ_OK)res).res.get_a();
  84             monitors[i] = ((Result_C2Tuple_BlockHashChannelMonitorZDecodeErrorZ.Result_C2Tuple_BlockHashChannelMonitorZDecodeErrorZ_OK) res).res.get_b();
  85             this.channel_monitors[i] = TwoTuple_BlockHashChannelMonitorZ.of(block_hash, monitors[i]);
  86         }
  87         Result_C2Tuple_BlockHashChannelManagerZDecodeErrorZ res =
  88                 UtilMethods.C2Tuple_BlockHashChannelManagerZ_read(channel_manager_serialized, keys_interface, fee_estimator, chain_monitor.as_Watch(), tx_broadcaster,
  89                         logger, UserConfig.with_default(), monitors);
  90         if (res instanceof Result_C2Tuple_BlockHashChannelManagerZDecodeErrorZ.Result_C2Tuple_BlockHashChannelManagerZDecodeErrorZ_Err) {
  91             throw new InvalidSerializedDataException();
  92         }
  93         this.channel_manager = ((Result_C2Tuple_BlockHashChannelManagerZDecodeErrorZ.Result_C2Tuple_BlockHashChannelManagerZDecodeErrorZ_OK)res).res.get_b();
  94         this.channel_manager_latest_block_hash = ((Result_C2Tuple_BlockHashChannelManagerZDecodeErrorZ.Result_C2Tuple_BlockHashChannelManagerZDecodeErrorZ_OK)res).res.get_a();
  95         this.chain_monitor = chain_monitor;
  96         this.logger = logger;
  97         byte[] random_data = keys_interface.get_secure_random_bytes();
  98         this.net_graph = net_graph;
  99         if (net_graph != null) {
 100             //TODO: We really need to expose the Access here to let users prevent DoS issues
 101             this.graph_msg_handler = NetGraphMsgHandler.of(net_graph, Option_AccessZ.none(), logger);
 102             this.peer_manager = PeerManager.of(channel_manager.as_ChannelMessageHandler(),
 103                     graph_msg_handler.as_RoutingMessageHandler(),
 104                     keys_interface.get_node_secret(), random_data, logger, no_custom_messages.as_CustomMessageHandler());
 105         } else {
 106             this.graph_msg_handler = null;
 107             this.peer_manager = PeerManager.of(channel_manager.as_ChannelMessageHandler(), no_custom_messages.as_RoutingMessageHandler(),
 108                     keys_interface.get_node_secret(), random_data, logger, no_custom_messages.as_CustomMessageHandler());
 109         }
 110         NioPeerHandler nio_peer_handler = null;
 111         try {
 112             nio_peer_handler = new NioPeerHandler(this.peer_manager);
 113         } catch (IOException e) {
 114             throw new IllegalStateException("We should never fail to construct nio objects unless we're on a platform that cannot run LDK.");
 115         }
 116         this.nio_peer_handler = nio_peer_handler;
 117         if (filter != null) {
 118             for (ChannelMonitor monitor : monitors) {
 119                 monitor.load_outputs_to_watch(filter);
 120             }
 121         }
 122     }
 123
 124     /**
 125      * Constructs a channel manager from the given interface implementations
 126      */
 127     public ChannelManagerConstructor(Network network, UserConfig config, byte[] current_blockchain_tip_hash, int current_blockchain_tip_height,
 128                                      KeysInterface keys_interface, FeeEstimator fee_estimator, ChainMonitor chain_monitor,
 129                                      @Nullable NetworkGraph net_graph,
 130                                      BroadcasterInterface tx_broadcaster, Logger logger) {
 131         final IgnoringMessageHandler no_custom_messages = IgnoringMessageHandler.of();
 132         channel_monitors = new TwoTuple_BlockHashChannelMonitorZ[0];
 133         channel_manager_latest_block_hash = null;
 134         this.chain_monitor = chain_monitor;
 135         BestBlock block = BestBlock.of(current_blockchain_tip_hash, current_blockchain_tip_height);
 136         ChainParameters params = ChainParameters.of(network, block);
 137         channel_manager = ChannelManager.of(fee_estimator, chain_monitor.as_Watch(), tx_broadcaster, logger, keys_interface, config, params);
 138         this.logger = logger;
 139         byte[] random_data = keys_interface.get_secure_random_bytes();
 140         this.net_graph = net_graph;
 141         if (net_graph != null) {
 142             //TODO: We really need to expose the Access here to let users prevent DoS issues
 143             this.graph_msg_handler = NetGraphMsgHandler.of(net_graph, Option_AccessZ.none(), logger);
 144             this.peer_manager = PeerManager.of(channel_manager.as_ChannelMessageHandler(),
 145                     graph_msg_handler.as_RoutingMessageHandler(),
 146                     keys_interface.get_node_secret(), random_data, logger, no_custom_messages.as_CustomMessageHandler());
 147         } else {
 148             this.graph_msg_handler = null;
 149             this.peer_manager = PeerManager.of(channel_manager.as_ChannelMessageHandler(), no_custom_messages.as_RoutingMessageHandler(),
 150                     keys_interface.get_node_secret(), random_data, logger, no_custom_messages.as_CustomMessageHandler());
 151         }
 152         NioPeerHandler nio_peer_handler = null;
 153         try {
 154             nio_peer_handler = new NioPeerHandler(this.peer_manager);
 155         } catch (IOException e) {
 156             throw new IllegalStateException("We should never fail to construct nio objects unless we're on a platform that cannot run LDK.");
 157         }
 158         this.nio_peer_handler = nio_peer_handler;
 159     }
 160
 161     /**
 162      * Abstract interface which should handle Events and persist the ChannelManager. When you call chain_sync_completed
 163      * a background thread is started which will automatically call these methods for you when events occur.
 164      */
 165     public interface EventHandler {
 166         void handle_event(Event events);
 167         void persist_manager(byte[] channel_manager_bytes);
 168     }
 169
 170     BackgroundProcessor background_processor = null;
 171
 172     /**
 173      * Utility which adds all of the deserialized ChannelMonitors to the chain watch so that further updates from the
 174      * ChannelManager are processed as normal.
 175      *
 176      * This also spawns a background thread which will call the appropriate methods on the provided
 177      * EventHandler as required.
 178      */
 179     public void chain_sync_completed(EventHandler event_handler, @Nullable LockableScore scorer) {
 180         if (background_processor != null) { return; }
 181         for (TwoTuple_BlockHashChannelMonitorZ monitor: channel_monitors) {
 182             this.chain_monitor.as_Watch().watch_channel(monitor.get_b().get_funding_txo().get_a(), monitor.get_b());
 183         }
 184         org.ldk.structs.EventHandler ldk_handler = org.ldk.structs.EventHandler.new_impl(event_handler::handle_event);
 185         if (this.net_graph != null && scorer != null) {
 186             Router router = DefaultRouter.of(net_graph, logger).as_Router();
 187             this.payer = InvoicePayer.of(this.channel_manager.as_Payer(), router, scorer, this.logger, ldk_handler, RetryAttempts.of(3));
 188 assert this.payer != null;
 189             ldk_handler = this.payer.as_EventHandler();
 190         }
 191
 192         background_processor = BackgroundProcessor.start(org.ldk.structs.ChannelManagerPersister.new_impl(channel_manager -> {
 193             event_handler.persist_manager(channel_manager.write());
 194             return Result_NoneErrorZ.ok();
 195         }), ldk_handler, this.chain_monitor, this.channel_manager, this.graph_msg_handler, this.peer_manager, this.logger);
 196     }
 197
 198     /**
 199      * Interrupt the background thread, stopping the background handling of events.
 200      */
 201     public void interrupt() {
 202         this.background_processor.stop();
 203         this.nio_peer_handler.interrupt();
 204     }
 205 }