Added importFromArchive() feature

This allows archived blocks to be imported back into HSQLDB in order to make them SQL-compatible again.

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

@@ -105,6 +105,21 @@ public class BlockArchiveReader {
         return null;
     }
 
+    public List<Triple<BlockData, List<TransactionData>, List<ATStateData>>> fetchBlocksFromRange(
+            int startHeight, int endHeight) {
+
+        List<Triple<BlockData, List<TransactionData>, List<ATStateData>>> blockInfoList = new ArrayList<>();
+
+        for (int height = startHeight; height <= endHeight; height++) {
+            Triple<BlockData, List<TransactionData>, List<ATStateData>> blockInfo = this.fetchBlockAtHeight(height);
+            if (blockInfo == null) {
+                return blockInfoList;
+            }
+            blockInfoList.add(blockInfo);
+        }
+        return blockInfoList;
+    }
+
     public Integer fetchHeightForSignature(byte[] signature, Repository repository) {
         // Lookup the height for the requested signature
         try {

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

@@ -36,6 +36,18 @@ public interface BlockArchiveRepository {
      */
     public BlockData fromHeight(int height) throws DataException;
 
+    /**
+     * Returns a list of BlockData objects from archive using
+     * block height range.
+     *
+     * @param startHeight
+     * @return a list of BlockData objects, or an empty list if
+     * not found in blockchain. It is not guaranteed that all
+     * requested blocks will be returned.
+     * @throws DataException
+     */
+    public List<BlockData> fromRange(int startHeight, int endHeight) throws DataException;
+
     /**
      * Returns BlockData from archive using block reference.
      * Currently relies on a child block being the one block

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

@@ -3,6 +3,7 @@ package org.qortal.repository.hsqldb;
 import org.qortal.api.ApiError;
 import org.qortal.api.ApiExceptionFactory;
 import org.qortal.api.model.BlockSignerSummary;
+import org.qortal.block.Block;
 import org.qortal.data.block.BlockArchiveData;
 import org.qortal.data.block.BlockData;
 import org.qortal.data.block.BlockSummaryData;
@@ -53,6 +54,20 @@ public class HSQLDBBlockArchiveRepository implements BlockArchiveRepository {
         return null;
     }
 
+    @Override
+    public List<BlockData> fromRange(int startHeight, int endHeight) throws DataException {
+        List<BlockData> blocks = new ArrayList<>();
+
+        for (int height = startHeight; height < endHeight; height++) {
+            BlockData blockData = this.fromHeight(height);
+            if (blockData == null) {
+                return blocks;
+            }
+            blocks.add(blockData);
+        }
+        return blocks;
+    }
+
     @Override
     public BlockData fromReference(byte[] reference) throws DataException {
         BlockData referenceBlock = this.repository.getBlockArchiveRepository().fromSignature(reference);

src/main/java/org/qortal/utils/BlockArchiveUtils.java

@@ -0,0 +1,78 @@
+package org.qortal.utils;
+
+import org.qortal.data.at.ATStateData;
+import org.qortal.data.block.BlockData;
+import org.qortal.data.transaction.TransactionData;
+import org.qortal.repository.BlockArchiveReader;
+import org.qortal.repository.DataException;
+import org.qortal.repository.Repository;
+
+import java.util.List;
+
+public class BlockArchiveUtils {
+
+    /**
+     * importFromArchive
+     * <p>
+     * Reads the requested block range from the archive
+     * and imports the BlockData and AT state data hashes
+     * This can be used to convert a block archive back
+     * into the HSQLDB, in order to make it SQL-compatible
+     * again.
+     * <p>
+     * Note: calls discardChanges() and saveChanges(), so
+     * make sure that you commit any existing repository
+     * changes before calling this method.
+     *
+     * @param startHeight The earliest block to import
+     * @param endHeight The latest block to import
+     * @param repository A clean repository session
+     * @throws DataException
+     */
+    public static void importFromArchive(int startHeight, int endHeight, Repository repository) throws DataException {
+        repository.discardChanges();
+        final int requestedRange = endHeight+1-startHeight;
+
+        List<Triple<BlockData, List<TransactionData>, List<ATStateData>>> blockInfoList =
+                BlockArchiveReader.getInstance().fetchBlocksFromRange(startHeight, endHeight);
+
+        // Ensure that we have received all of the requested blocks
+        if (blockInfoList == null || blockInfoList.isEmpty()) {
+            throw new IllegalStateException("No blocks found when importing from archive");
+        }
+        if (blockInfoList.size() != requestedRange) {
+            throw new IllegalStateException("Non matching block count when importing from archive");
+        }
+        Triple<BlockData, List<TransactionData>, List<ATStateData>> firstBlock = blockInfoList.get(0);
+        if (firstBlock == null || firstBlock.getA().getHeight() != startHeight) {
+            throw new IllegalStateException("Non matching first block when importing from archive");
+        }
+        if (blockInfoList.size() > 0) {
+            Triple<BlockData, List<TransactionData>, List<ATStateData>> lastBlock =
+                    blockInfoList.get(blockInfoList.size() - 1);
+            if (lastBlock == null || lastBlock.getA().getHeight() != endHeight) {
+                throw new IllegalStateException("Non matching last block when importing from archive");
+            }
+        }
+
+        // Everything seems okay, so go ahead with the import
+        for (Triple<BlockData, List<TransactionData>, List<ATStateData>> blockInfo : blockInfoList) {
+            try {
+                // Save block
+                repository.getBlockRepository().save(blockInfo.getA());
+
+                // Save AT state data hashes
+                for (ATStateData atStateData : blockInfo.getC()) {
+                    atStateData.setHeight(blockInfo.getA().getHeight());
+                    repository.getATRepository().save(atStateData);
+                }
+
+            } catch (DataException e) {
+                repository.discardChanges();
+                throw new IllegalStateException("Unable to import blocks from archive");
+            }
+        }
+        repository.saveChanges();
+    }
+
+}