com.google.bitcoin.kits.WalletAppKit Maven / Gradle / Ivy
The newest version!
/*
* Copyright 2013 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.google.bitcoin.kits;
import com.google.bitcoin.core.*;
import com.google.bitcoin.net.discovery.DnsDiscovery;
import com.google.bitcoin.store.BlockStoreException;
import com.google.bitcoin.store.SPVBlockStore;
import com.google.bitcoin.store.WalletProtobufSerializer;
import com.google.common.util.concurrent.AbstractIdleService;
import com.google.common.util.concurrent.FutureCallback;
import com.google.common.util.concurrent.Futures;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.InetAddress;
import java.net.UnknownHostException;
import java.util.concurrent.TimeUnit;
import static com.google.common.base.Preconditions.checkNotNull;
import static com.google.common.base.Preconditions.checkState;
/**
* Utility class that wraps the boilerplate needed to set up a new SPV bitcoinj app. Instantiate it with a directory
* and file prefix, optionally configure a few things, then use start or startAndWait. The object will construct and
* configure a {@link BlockChain}, {@link SPVBlockStore}, {@link Wallet} and {@link PeerGroup}. Depending on the value
* of the blockingStartup property, startup will be considered complete once the block chain has fully synchronized,
* so it can take a while.
*
* To add listeners and modify the objects that are constructed, you can either do that by overriding the
* {@link #onSetupCompleted()} method (which will run on a background thread) and make your changes there,
* or by waiting for the service to start and then accessing the objects from wherever you want. However, you cannot
* access the objects this class creates until startup is complete.
*
* The asynchronous design of this class may seem puzzling (just use {@link #startAndWait()} if you don't want that).
* It is to make it easier to fit bitcoinj into GUI apps, which require a high degree of responsiveness on their main
* thread which handles all the animation and user interaction. Even when blockingStart is false, initializing bitcoinj
* means doing potentially blocking file IO, generating keys and other potentially intensive operations. By running it
* on a background thread, there's no risk of accidentally causing UI lag.
*
* Note that {@link #startAndWait()} can throw an unchecked {@link com.google.common.util.concurrent.UncheckedExecutionException}
* if anything goes wrong during startup - you should probably handle it and use {@link Exception#getCause()} to figure
* out what went wrong more precisely. Same thing if you use the async start() method.
*/
public class WalletAppKit extends AbstractIdleService {
protected final String filePrefix;
protected final NetworkParameters params;
protected volatile BlockChain vChain;
protected volatile SPVBlockStore vStore;
protected volatile Wallet vWallet;
protected volatile PeerGroup vPeerGroup;
protected final File directory;
protected volatile File vWalletFile;
protected boolean useAutoSave = true;
protected PeerAddress[] peerAddresses;
protected PeerEventListener downloadListener;
protected boolean autoStop = true;
protected InputStream checkpoints;
protected boolean blockingStartup = true;
protected String userAgent, version;
public WalletAppKit(NetworkParameters params, File directory, String filePrefix) {
this.params = checkNotNull(params);
this.directory = checkNotNull(directory);
this.filePrefix = checkNotNull(filePrefix);
}
/** Will only connect to the given addresses. Cannot be called after startup. */
public WalletAppKit setPeerNodes(PeerAddress... addresses) {
checkState(state() == State.NEW, "Cannot call after startup");
this.peerAddresses = addresses;
return this;
}
/** Will only connect to localhost. Cannot be called after startup. */
public WalletAppKit connectToLocalHost() {
try {
final InetAddress localHost = InetAddress.getLocalHost();
return setPeerNodes(new PeerAddress(localHost, params.getPort()));
} catch (UnknownHostException e) {
// Borked machine with no loopback adapter configured properly.
throw new RuntimeException(e);
}
}
/** If true, the wallet will save itself to disk automatically whenever it changes. */
public WalletAppKit setAutoSave(boolean value) {
checkState(state() == State.NEW, "Cannot call after startup");
useAutoSave = value;
return this;
}
/**
* If you want to learn about the sync process, you can provide a listener here. For instance, a
* {@link DownloadListener} is a good choice.
*/
public WalletAppKit setDownloadListener(PeerEventListener listener) {
this.downloadListener = listener;
return this;
}
/** If true, will register a shutdown hook to stop the library. Defaults to true. */
public WalletAppKit setAutoStop(boolean autoStop) {
this.autoStop = autoStop;
return this;
}
/**
* If set, the file is expected to contain a checkpoints file calculated with BuildCheckpoints. It makes initial
* block sync faster for new users - please refer to the documentation on the bitcoinj website for further details.
*/
public WalletAppKit setCheckpoints(InputStream checkpoints) {
this.checkpoints = checkNotNull(checkpoints);
return this;
}
/**
* If true (the default) then the startup of this service won't be considered complete until the network has been
* brought up, peer connections established and the block chain synchronised. Therefore {@link #startAndWait()} can
* potentially take a very long time. If false, then startup is considered complete once the network activity
* begins and peer connections/block chain sync will continue in the background.
*/
public WalletAppKit setBlockingStartup(boolean blockingStartup) {
this.blockingStartup = blockingStartup;
return this;
}
/**
* Sets the string that will appear in the subver field of the version message.
* @param userAgent A short string that should be the name of your app, e.g. "My Wallet"
* @param version A short string that contains the version number, e.g. "1.0-BETA"
*/
public WalletAppKit setUserAgent(String userAgent, String version) {
this.userAgent = checkNotNull(userAgent);
this.version = checkNotNull(version);
return this;
}
/**
* Override this to load all wallet extensions if any are necessary.
*
* When this is called, chain(), store(), and peerGroup() will return the created objects, however they are not
* initialized/started
*/
protected void addWalletExtensions() throws Exception { }
/**
* This method is invoked on a background thread after all objects are initialised, but before the peer group
* or block chain download is started. You can tweak the objects configuration here.
*/
protected void onSetupCompleted() { }
@Override
protected void startUp() throws Exception {
// Runs in a separate thread.
if (!directory.exists()) {
if (!directory.mkdir()) {
throw new IOException("Could not create named directory.");
}
}
try {
File chainFile = new File(directory, filePrefix + ".spvchain");
boolean chainFileExists = chainFile.exists();
vWalletFile = new File(directory, filePrefix + ".wallet");
boolean shouldReplayWallet = vWalletFile.exists() && !chainFileExists;
vStore = new SPVBlockStore(params, chainFile);
if (!chainFileExists && checkpoints != null) {
// Ugly hack! We have to create the wallet once here to learn the earliest key time, and then throw it
// away. The reason is that wallet extensions might need access to peergroups/chains/etc so we have to
// create the wallet later, but we need to know the time early here before we create the BlockChain
// object.
long time = Long.MAX_VALUE;
if (vWalletFile.exists()) {
Wallet wallet = new Wallet(params);
FileInputStream stream = new FileInputStream(vWalletFile);
new WalletProtobufSerializer().readWallet(WalletProtobufSerializer.parseToProto(stream), wallet);
time = wallet.getEarliestKeyCreationTime();
}
CheckpointManager.checkpoint(params, checkpoints, vStore, time);
}
vChain = new BlockChain(params, vStore);
vPeerGroup = createPeerGroup();
if (this.userAgent != null)
vPeerGroup.setUserAgent(userAgent, version);
if (vWalletFile.exists()) {
FileInputStream walletStream = new FileInputStream(vWalletFile);
try {
vWallet = new Wallet(params);
addWalletExtensions(); // All extensions must be present before we deserialize
new WalletProtobufSerializer().readWallet(WalletProtobufSerializer.parseToProto(walletStream), vWallet);
if (shouldReplayWallet)
vWallet.clearTransactions(0);
} finally {
walletStream.close();
}
} else {
vWallet = new Wallet(params);
vWallet.addKey(new ECKey());
addWalletExtensions();
vWallet.saveToFile(vWalletFile);
}
if (useAutoSave) {
vWallet.autosaveToFile(vWalletFile, 200, TimeUnit.MILLISECONDS, null);
}
// Set up peer addresses or discovery first, so if wallet extensions try to broadcast a transaction
// before we're actually connected the broadcast waits for an appropriate number of connections.
if (peerAddresses != null) {
for (PeerAddress addr : peerAddresses) vPeerGroup.addAddress(addr);
peerAddresses = null;
} else {
vPeerGroup.addPeerDiscovery(new DnsDiscovery(params));
}
vChain.addWallet(vWallet);
vPeerGroup.addWallet(vWallet);
onSetupCompleted();
if (blockingStartup) {
vPeerGroup.startAndWait();
// Make sure we shut down cleanly.
installShutdownHook();
// TODO: Be able to use the provided download listener when doing a blocking startup.
final DownloadListener listener = new DownloadListener();
vPeerGroup.startBlockChainDownload(listener);
listener.await();
} else {
Futures.addCallback(vPeerGroup.start(), new FutureCallback() {
@Override
public void onSuccess(State result) {
final PeerEventListener l = downloadListener == null ? new DownloadListener() : downloadListener;
vPeerGroup.startBlockChainDownload(l);
}
@Override
public void onFailure(Throwable t) {
throw new RuntimeException(t);
}
});
}
} catch (BlockStoreException e) {
throw new IOException(e);
}
}
protected PeerGroup createPeerGroup() {
return new PeerGroup(params, vChain);
}
private void installShutdownHook() {
if (autoStop) Runtime.getRuntime().addShutdownHook(new Thread() {
@Override public void run() {
try {
WalletAppKit.this.stopAndWait();
} catch (Exception e) {
throw new RuntimeException(e);
}
}
});
}
@Override
protected void shutDown() throws Exception {
// Runs in a separate thread.
try {
vPeerGroup.stopAndWait();
vWallet.saveToFile(vWalletFile);
vStore.close();
vPeerGroup = null;
vWallet = null;
vStore = null;
vChain = null;
} catch (BlockStoreException e) {
throw new IOException(e);
}
}
public NetworkParameters params() {
return params;
}
public BlockChain chain() {
checkState(state() == State.STARTING || state() == State.RUNNING, "Cannot call until startup is complete");
return vChain;
}
public SPVBlockStore store() {
checkState(state() == State.STARTING || state() == State.RUNNING, "Cannot call until startup is complete");
return vStore;
}
public Wallet wallet() {
checkState(state() == State.STARTING || state() == State.RUNNING, "Cannot call until startup is complete");
return vWallet;
}
public PeerGroup peerGroup() {
checkState(state() == State.STARTING || state() == State.RUNNING, "Cannot call until startup is complete");
return vPeerGroup;
}
public File directory() {
return directory;
}
}