1 package org.ldk.batteries;
3 import javax.annotation.Nullable;
4 import org.ldk.enums.Network;
5 import org.ldk.structs.*;
6 import org.ldk.util.TwoTuple;
8 import java.io.IOException;
12 * A simple utility class which assists in constructing a fresh or deserializing from disk a ChannelManager and one or
13 * more ChannelMonitors.
15 * Also constructs a PeerManager and spawns a background thread to monitor for and notify you of relevant Events.
17 public class ChannelManagerConstructor {
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.
22 public static class InvalidSerializedDataException extends Exception {}
25 * The ChannelManager either deserialized or newly-constructed.
27 public final ChannelManager channel_manager;
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.
32 public final byte[] channel_manager_latest_block_hash;
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.
39 public final TwoTuple_BlockHashChannelMonitorZ[] channel_monitors;
41 * A PeerManager which is constructed to pass messages and handle connections to peers.
43 public final PeerManager peer_manager;
45 * A NioPeerHandler which manages a background thread to handle socket events and pass them to the peer_manager.
47 public final NioPeerHandler nio_peer_handler;
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.
52 * It should be used to send payments instead of doing so directly via the `channel_manager`.
54 * When payments are made through this, they are automatically retried and the provided Scorer
55 * will be updated with payment failure data.
57 @Nullable public InvoicePayer payer;
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;
65 * Deserializes a channel manager and a set of channel monitors from the given serialized copies and interface implementations
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.
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();
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]);
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();
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;
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());
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());
110 NioPeerHandler nio_peer_handler = null;
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.");
116 this.nio_peer_handler = nio_peer_handler;
117 if (filter != null) {
118 for (ChannelMonitor monitor : monitors) {
119 monitor.load_outputs_to_watch(filter);
125 * Constructs a channel manager from the given interface implementations
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());
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());
152 NioPeerHandler nio_peer_handler = null;
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.");
158 this.nio_peer_handler = nio_peer_handler;
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.
165 public interface EventHandler {
166 void handle_event(Event events);
167 void persist_manager(byte[] channel_manager_bytes);
170 BackgroundProcessor background_processor = null;
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.
176 * This also spawns a background thread which will call the appropriate methods on the provided
177 * EventHandler as required.
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());
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();
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);
199 * Interrupt the background thread, stopping the background handling of events.
201 public void interrupt() {
202 this.background_processor.stop();
203 this.nio_peer_handler.interrupt();