Don't rebuild repository or export node-local data during repository build if repository was 'pristine'.

Under certain conditions, e.g. non-existent database files, the repository would be created
and then immediately be re-created.

Not only was this unnecessary, but HSQLDBDatabaseUpdates would attempt to export the node-local
data twice, which would cause an error due to existing .script files.

The fix is three-pronged:

1. Don't immediately rebuild the repository if it's only just been built
2. Don't export the empty node-local data if repository has only just been built
3. Don't export the node-local data if it's empty

src/main/java/org/qortal/block/BlockChain.java

@@ -531,7 +531,8 @@ public class BlockChain {
 
 	private static void rebuildBlockchain() throws DataException {
 		// (Re)build repository
-		RepositoryManager.rebuild();
+		if (!RepositoryManager.wasPristineAtOpen())
+			RepositoryManager.rebuild();
 
 		try (final Repository repository = RepositoryManager.getRepository()) {
 			GenesisBlock genesisBlock = GenesisBlock.getInstance(repository);

src/main/java/org/qortal/repository/RepositoryFactory.java

@@ -2,6 +2,8 @@ package org.qortal.repository;
 
 public interface RepositoryFactory {
 
+	public boolean wasPristineAtOpen();
+
 	public RepositoryFactory reopen() throws DataException;
 
 	public Repository getRepository() throws DataException;

src/main/java/org/qortal/repository/RepositoryManager.java

@@ -8,6 +8,13 @@ public abstract class RepositoryManager {
 		repositoryFactory = newRepositoryFactory;
 	}
 
+	public static boolean wasPristineAtOpen() throws DataException {
+		if (repositoryFactory == null)
+			throw new DataException("No repository available");
+
+		return repositoryFactory.wasPristineAtOpen();
+	}
+
 	public static Repository getRepository() throws DataException {
 		if (repositoryFactory == null)
 			throw new DataException("No repository available");

src/main/java/org/qortal/repository/hsqldb/HSQLDBDatabaseUpdates.java

@@ -18,11 +18,16 @@ public class HSQLDBDatabaseUpdates {
 	/**
 	 * Apply any incremental changes to database schema.
 	 * 
+	 * @return true if database was non-existent/empty, false otherwise
 	 * @throws SQLException
 	 */
-	public static void updateDatabase(Connection connection) throws SQLException {
-		while (databaseUpdating(connection))
+	public static boolean updateDatabase(Connection connection) throws SQLException {
+		final boolean wasPristine = fetchDatabaseVersion(connection) == 0;
+
+		while (databaseUpdating(connection, wasPristine))
 			incrementDatabaseVersion(connection);
+
+		return wasPristine;
 	}
 
 	/**
@@ -40,23 +45,21 @@ public class HSQLDBDatabaseUpdates {
 	/**
 	 * Fetch current version of database schema.
 	 * 
-	 * @return int, 0 if no schema yet
+	 * @return database version, or 0 if no schema yet
 	 * @throws SQLException
 	 */
 	private static int fetchDatabaseVersion(Connection connection) throws SQLException {
-		int databaseVersion = 0;
-
 		try (Statement stmt = connection.createStatement()) {
 			if (stmt.execute("SELECT version FROM DatabaseInfo"))
 				try (ResultSet resultSet = stmt.getResultSet()) {
 					if (resultSet.next())
-						databaseVersion = resultSet.getInt(1);
+						return resultSet.getInt(1);
 				}
 		} catch (SQLException e) {
 			// empty database
 		}
 
-		return databaseVersion;
+		return 0;
 	}
 
 	/**
@@ -65,7 +68,7 @@ public class HSQLDBDatabaseUpdates {
 	 * @return true - if a schema update happened, false otherwise
 	 * @throws SQLException
 	 */
-	private static boolean databaseUpdating(Connection connection) throws SQLException {
+	private static boolean databaseUpdating(Connection connection, boolean wasPristine) throws SQLException {
 		int databaseVersion = fetchDatabaseVersion(connection);
 
 		try (Statement stmt = connection.createStatement()) {
@@ -695,11 +698,24 @@ public class HSQLDBDatabaseUpdates {
 				case 30:
 					// Split AT state data off to new table for better performance/management.
 
-					if (!"mem".equals(HSQLDBRepository.getDbPathname(connection.getMetaData().getURL()))) {
+					if (!wasPristine && !"mem".equals(HSQLDBRepository.getDbPathname(connection.getMetaData().getURL()))) {
 						// First, backup node-local data in case user wants to avoid long reshape and use bootstrap instead
-						stmt.execute("PERFORM EXPORT SCRIPT FOR TABLE MintingAccounts DATA TO 'MintingAccounts.script'");
-						stmt.execute("PERFORM EXPORT SCRIPT FOR TABLE TradeBotStates DATA TO 'TradeBotStates.script'");
-						LOGGER.info("Exported sensitive/node-local data: minting keys and trade bot states");
+						try (ResultSet resultSet = stmt.executeQuery("SELECT COUNT(*) FROM MintingAccounts")) {
+							int rowCount = resultSet.next() ? resultSet.getInt(1) : 0;
+							if (rowCount > 0) {
+								stmt.execute("PERFORM EXPORT SCRIPT FOR TABLE MintingAccounts DATA TO 'MintingAccounts.script'");
+								LOGGER.info("Exported sensitive/node-local minting keys into MintingAccounts.script");
+							}
+						}
+
+						try (ResultSet resultSet = stmt.executeQuery("SELECT COUNT(*) FROM TradeBotStates")) {
+							int rowCount = resultSet.next() ? resultSet.getInt(1) : 0;
+							if (rowCount > 0) {
+								stmt.execute("PERFORM EXPORT SCRIPT FOR TABLE TradeBotStates DATA TO 'TradeBotStates.script'");
+								LOGGER.info("Exported sensitive/node-local trade-bot states into TradeBotStates.script");
+							}
+						}
+
 						LOGGER.info("If following reshape takes too long, use bootstrap and import node-local data using API's POST /admin/repository/data");
 					}
 

src/main/java/org/qortal/repository/hsqldb/HSQLDBRepositoryFactory.java

@@ -25,6 +25,7 @@ public class HSQLDBRepositoryFactory implements RepositoryFactory {
 
 	private String connectionUrl;
 	private HSQLDBPool connectionPool;
+	private final boolean wasPristine;
 
 	/**
 	 * Constructs new RepositoryFactory using passed <tt>connectionUrl</tt>.
@@ -65,12 +66,17 @@ public class HSQLDBRepositoryFactory implements RepositoryFactory {
 
 		// Perform DB updates?
 		try (final Connection connection = this.connectionPool.getConnection()) {
-			HSQLDBDatabaseUpdates.updateDatabase(connection);
+			this.wasPristine = HSQLDBDatabaseUpdates.updateDatabase(connection);
 		} catch (SQLException e) {
 			throw new DataException("Repository initialization error", e);
 		}
 	}
 
+	@Override
+	public boolean wasPristineAtOpen() {
+		return this.wasPristine;
+	}
+
 	@Override
 	public RepositoryFactory reopen() throws DataException {
 		return new HSQLDBRepositoryFactory(this.connectionUrl);