system info and database connection status access

src/main/java/org/hsqldb/jdbc/HSQLDBPoolMonitored.java

@@ -0,0 +1,173 @@
+package org.hsqldb.jdbc;
+
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.hsqldb.jdbc.pool.JDBCPooledConnection;
+import org.qortal.data.system.DbConnectionInfo;
+import org.qortal.repository.hsqldb.HSQLDBRepositoryFactory;
+
+import javax.sql.ConnectionEvent;
+import javax.sql.PooledConnection;
+import java.sql.Connection;
+import java.sql.SQLException;
+import java.util.Comparator;
+import java.util.List;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.stream.Collectors;
+
+/**
+ * Class HSQLDBPoolMonitored
+ *
+ * This class uses the same logic as HSQLDBPool. The only difference is it monitors the state of every connection
+ * to the database. This is used for debugging purposes only.
+ */
+public class HSQLDBPoolMonitored extends HSQLDBPool {
+
+	private static final Logger LOGGER = LogManager.getLogger(HSQLDBRepositoryFactory.class);
+
+	private static final String EMPTY = "Empty";
+	private static final String AVAILABLE = "Available";
+	private static final String ALLOCATED = "Allocated";
+
+	private ConcurrentHashMap<Integer, DbConnectionInfo> infoByIndex;
+
+	public HSQLDBPoolMonitored(int poolSize) {
+		super(poolSize);
+
+		this.infoByIndex = new ConcurrentHashMap<>(poolSize);
+	}
+
+	/**
+	 * Tries to retrieve a new connection using the properties that have already been
+	 * set.
+	 *
+	 * @return  a connection to the data source, or null if no spare connections in pool
+	 * @exception SQLException if a database access error occurs
+	 */
+	public Connection tryConnection() throws SQLException {
+		for (int i = 0; i < states.length(); i++) {
+			if (states.compareAndSet(i, RefState.available, RefState.allocated)) {
+				JDBCPooledConnection pooledConnection = connections[i];
+
+				if (pooledConnection == null)
+					// Probably shutdown situation
+					return null;
+
+				infoByIndex.put(i, new DbConnectionInfo(System.currentTimeMillis(), Thread.currentThread().getName(), ALLOCATED));
+
+				return pooledConnection.getConnection();
+			}
+
+			if (states.compareAndSet(i, RefState.empty, RefState.allocated)) {
+				try {
+					JDBCPooledConnection pooledConnection = (JDBCPooledConnection) source.getPooledConnection();
+
+					if (pooledConnection == null)
+						// Probably shutdown situation
+						return null;
+
+					pooledConnection.addConnectionEventListener(this);
+					pooledConnection.addStatementEventListener(this);
+					connections[i] = pooledConnection;
+
+					infoByIndex.put(i, new DbConnectionInfo(System.currentTimeMillis(), Thread.currentThread().getName(), ALLOCATED));
+
+					return pooledConnection.getConnection();
+				} catch (SQLException e) {
+					states.set(i, RefState.empty);
+					infoByIndex.put(i, new DbConnectionInfo(System.currentTimeMillis(), Thread.currentThread().getName(), EMPTY));
+				}
+			}
+		}
+
+		return null;
+	}
+
+	public Connection getConnection() throws SQLException {
+		int var1 = 300;
+		if (this.source.loginTimeout != 0) {
+			var1 = this.source.loginTimeout * 10;
+		}
+
+		if (this.closed) {
+			throw new SQLException("connection pool is closed");
+		} else {
+			for(int var2 = 0; var2 < var1; ++var2) {
+				for(int var3 = 0; var3 < this.states.length(); ++var3) {
+					if (this.states.compareAndSet(var3, 1, 2)) {
+						infoByIndex.put(var3, new DbConnectionInfo(System.currentTimeMillis(), Thread.currentThread().getName(), ALLOCATED));
+						return this.connections[var3].getConnection();
+					}
+
+					if (this.states.compareAndSet(var3, 0, 2)) {
+						try {
+							JDBCPooledConnection var4 = (JDBCPooledConnection)this.source.getPooledConnection();
+							var4.addConnectionEventListener(this);
+							var4.addStatementEventListener(this);
+							this.connections[var3] = var4;
+
+							infoByIndex.put(var3, new DbConnectionInfo(System.currentTimeMillis(), Thread.currentThread().getName(), ALLOCATED));
+
+							return this.connections[var3].getConnection();
+						} catch (SQLException var6) {
+							this.states.set(var3, 0);
+							infoByIndex.put(var3, new DbConnectionInfo(System.currentTimeMillis(), Thread.currentThread().getName(), EMPTY));
+						}
+					}
+				}
+
+				try {
+					Thread.sleep(100L);
+				} catch (InterruptedException var5) {
+				}
+			}
+
+			throw JDBCUtil.invalidArgument();
+		}
+	}
+
+	public void connectionClosed(ConnectionEvent event) {
+		PooledConnection connection = (PooledConnection) event.getSource();
+
+		for (int i = 0; i < connections.length; i++) {
+			if (connections[i] == connection) {
+				states.set(i, RefState.available);
+				infoByIndex.put(i, new DbConnectionInfo(System.currentTimeMillis(), Thread.currentThread().getName(), AVAILABLE));
+				break;
+			}
+		}
+	}
+
+	public void connectionErrorOccurred(ConnectionEvent event) {
+		PooledConnection connection = (PooledConnection) event.getSource();
+
+		for (int i = 0; i < connections.length; i++) {
+			if (connections[i] == connection) {
+				states.set(i, RefState.allocated);
+				connections[i] = null;
+				states.set(i, RefState.empty);
+				infoByIndex.put(i, new DbConnectionInfo(System.currentTimeMillis(), Thread.currentThread().getName(), EMPTY));
+				break;
+			}
+		}
+	}
+
+	public List<DbConnectionInfo> getDbConnectionsStates() {
+
+		return infoByIndex.values().stream()
+			.sorted(Comparator.comparingLong(DbConnectionInfo::getUpdated))
+			.collect(Collectors.toList());
+	}
+
+	private int findConnectionIndex(ConnectionEvent connectionEvent) {
+		PooledConnection pooledConnection = (PooledConnection) connectionEvent.getSource();
+
+		for(int i = 0; i < this.connections.length; ++i) {
+			if (this.connections[i] == pooledConnection) {
+				return i;
+			}
+		}
+
+		return -1;
+	}
+}

src/main/java/org/qortal/api/model/DatasetStatus.java

@@ -0,0 +1,50 @@
+package org.qortal.api.model;
+
+import javax.xml.bind.annotation.XmlAccessType;
+import javax.xml.bind.annotation.XmlAccessorType;
+import java.util.Objects;
+
+// All properties to be converted to JSON via JAXB
+@XmlAccessorType(XmlAccessType.FIELD)
+public class DatasetStatus {
+
+    private String name;
+
+    private long count;
+
+    public DatasetStatus() {}
+
+    public DatasetStatus(String name, long count) {
+        this.name = name;
+        this.count = count;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public long getCount() {
+        return count;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+        DatasetStatus that = (DatasetStatus) o;
+        return count == that.count && Objects.equals(name, that.name);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(name, count);
+    }
+
+    @Override
+    public String toString() {
+        return "DatasetStatus{" +
+                "name='" + name + '\'' +
+                ", count=" + count +
+                '}';
+    }
+}

src/main/java/org/qortal/api/restricted/resource/AdminResource.java

@@ -32,6 +32,7 @@ import org.qortal.controller.Synchronizer.SynchronizationResult;
 import org.qortal.controller.repository.BlockArchiveRebuilder;
 import org.qortal.data.account.MintingAccountData;
 import org.qortal.data.account.RewardShareData;
+import org.qortal.data.system.DbConnectionInfo;
 import org.qortal.network.Network;
 import org.qortal.network.Peer;
 import org.qortal.network.PeerAddress;
@@ -40,6 +41,7 @@ import org.qortal.repository.DataException;
 import org.qortal.repository.Repository;
 import org.qortal.repository.RepositoryManager;
 import org.qortal.settings.Settings;
+import org.qortal.data.system.SystemInfo;
 import org.qortal.utils.Base58;
 import org.qortal.utils.NTP;
 
@@ -52,6 +54,7 @@ import java.net.InetSocketAddress;
 import java.net.UnknownHostException;
 import java.nio.file.Files;
 import java.nio.file.Paths;
+import java.util.ArrayList;
 import java.util.List;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.TimeoutException;
@@ -1064,4 +1067,50 @@ public class AdminResource {
 		return "true";
 	}
 
-}
+	@GET
+	@Path("/systeminfo")
+	@Operation(
+			summary = "System Information",
+			description = "System memory usage and available processors.",
+			responses = {
+					@ApiResponse(
+							description = "memory usage and available processors",
+							content = @Content(mediaType = MediaType.APPLICATION_JSON, schema = @Schema(implementation = SystemInfo.class))
+					)
+			}
+	)
+	@ApiErrors({ApiError.REPOSITORY_ISSUE})
+	public SystemInfo getSystemInformation() {
+
+		SystemInfo info
+			= new SystemInfo(
+				Runtime.getRuntime().freeMemory(),
+				Runtime.getRuntime().totalMemory() - Runtime.getRuntime().freeMemory(),
+				Runtime.getRuntime().totalMemory(),
+				Runtime.getRuntime().maxMemory(),
+				Runtime.getRuntime().availableProcessors());
+
+		return info;
+	}
+
+	@GET
+	@Path("/dbstates")
+	@Operation(
+			summary = "Get DB States",
+			description = "Get DB States",
+			responses = {
+					@ApiResponse(
+							content = @Content(mediaType = MediaType.APPLICATION_JSON, array = @ArraySchema(schema = @Schema(implementation = DbConnectionInfo.class)))
+					)
+			}
+	)
+	public List<DbConnectionInfo> getDbConnectionsStates() {
+
+		try {
+			return Controller.REPOSITORY_FACTORY.getDbConnectionsStates();
+		} catch (Exception e) {
+			LOGGER.error(e.getMessage(), e);
+			return new ArrayList<>(0);
+		}
+	}
+}

src/main/java/org/qortal/data/system/DbConnectionInfo.java

@@ -0,0 +1,35 @@
+package org.qortal.data.system;
+
+import javax.xml.bind.annotation.XmlAccessType;
+import javax.xml.bind.annotation.XmlAccessorType;
+
+@XmlAccessorType(XmlAccessType.FIELD)
+public class DbConnectionInfo {
+
+    private long updated;
+
+    private String owner;
+
+    private String state;
+
+    public DbConnectionInfo() {
+    }
+
+    public DbConnectionInfo(long timeOpened, String owner, String state) {
+        this.updated = timeOpened;
+        this.owner = owner;
+        this.state = state;
+    }
+
+    public long getUpdated() {
+        return updated;
+    }
+
+    public String getOwner() {
+        return owner;
+    }
+
+    public String getState() {
+        return state;
+    }
+}

src/main/java/org/qortal/data/system/SystemInfo.java

@@ -0,0 +1,49 @@
+package org.qortal.data.system;
+
+import javax.xml.bind.annotation.XmlAccessType;
+import javax.xml.bind.annotation.XmlAccessorType;
+
+@XmlAccessorType(XmlAccessType.FIELD)
+public class SystemInfo {
+
+    private long freeMemory;
+
+    private long memoryInUse;
+
+    private long totalMemory;
+
+    private long maxMemory;
+
+    private int availableProcessors;
+
+    public SystemInfo() {
+    }
+
+    public SystemInfo(long freeMemory, long memoryInUse, long totalMemory, long maxMemory, int availableProcessors) {
+        this.freeMemory = freeMemory;
+        this.memoryInUse = memoryInUse;
+        this.totalMemory = totalMemory;
+        this.maxMemory = maxMemory;
+        this.availableProcessors = availableProcessors;
+    }
+
+    public long getFreeMemory() {
+        return freeMemory;
+    }
+
+    public long getMemoryInUse() {
+        return memoryInUse;
+    }
+
+    public long getTotalMemory() {
+        return totalMemory;
+    }
+
+    public long getMaxMemory() {
+        return maxMemory;
+    }
+
+    public int getAvailableProcessors() {
+        return availableProcessors;
+    }
+}

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

@@ -5,6 +5,8 @@ import org.apache.logging.log4j.Logger;
 import org.hsqldb.HsqlException;
 import org.hsqldb.error.ErrorCode;
 import org.hsqldb.jdbc.HSQLDBPool;
+import org.hsqldb.jdbc.HSQLDBPoolMonitored;
+import org.qortal.data.system.DbConnectionInfo;
 import org.qortal.repository.DataException;
 import org.qortal.repository.Repository;
 import org.qortal.repository.RepositoryFactory;
@@ -14,6 +16,8 @@ import java.sql.Connection;
 import java.sql.DriverManager;
 import java.sql.SQLException;
 import java.sql.Statement;
+import java.util.ArrayList;
+import java.util.List;
 import java.util.Properties;
 
 public class HSQLDBRepositoryFactory implements RepositoryFactory {
@@ -57,7 +61,13 @@ public class HSQLDBRepositoryFactory implements RepositoryFactory {
 			HSQLDBRepository.attemptRecovery(connectionUrl, "backup");
 		}
 
-		this.connectionPool = new HSQLDBPool(Settings.getInstance().getRepositoryConnectionPoolSize());
+		if(Settings.getInstance().isConnectionPoolMonitorEnabled()) {
+			this.connectionPool = new HSQLDBPoolMonitored(Settings.getInstance().getRepositoryConnectionPoolSize());
+		}
+		else {
+			this.connectionPool = new HSQLDBPool(Settings.getInstance().getRepositoryConnectionPoolSize());
+		}
+
 		this.connectionPool.setUrl(this.connectionUrl);
 
 		Properties properties = new Properties();
@@ -153,4 +163,19 @@ public class HSQLDBRepositoryFactory implements RepositoryFactory {
 		return HSQLDBRepository.isDeadlockException(e);
 	}
 
+	/**
+	 * Get Connection States
+	 *
+	 * Get the database connection states, if database connection pool monitoring is enabled.
+	 *
+	 * @return the connection states if enabled, otherwise an empty list
+	 */
+	public List<DbConnectionInfo> getDbConnectionsStates() {
+		if( Settings.getInstance().isConnectionPoolMonitorEnabled() ) {
+			return ((HSQLDBPoolMonitored) this.connectionPool).getDbConnectionsStates();
+		}
+		else {
+			return new ArrayList<>(0);
+		}
+	}
 }

src/main/java/org/qortal/settings/Settings.java

@@ -501,6 +501,13 @@ public class Settings {
 	 */
     private boolean rewardRecordingOnly = true;
 
+	/**
+	 * Is The Connection Monitored?
+	 *
+	 * Is the database connection pooled monitored?
+	 */
+    private boolean connectionPoolMonitorEnabled = false;
+
     // Domain mapping
 	public static class ThreadLimit {
 		private String messageType;
@@ -1322,4 +1329,8 @@ public class Settings {
 	public boolean isRewardRecordingOnly() {
 		return rewardRecordingOnly;
 	}
+
+	public boolean isConnectionPoolMonitorEnabled() {
+		return connectionPoolMonitorEnabled;
+	}
 }