Add new modules: Resource Lock and Doorman

Issue-ID: CCSDK-2226
Signed-off-by: Stan Bonev <sb5356@att.com>
Change-Id: I30f83dd4a852fd185dbdaa9a833f5ba544d35ba1

6 files changed, 377 insertions, 0 deletions

diff --git a/lib/rlock/src/main/java/org/onap/ccsdk/features/lib/rlock/LockHelper.java b/lib/rlock/src/main/java/org/onap/ccsdk/features/lib/rlock/LockHelper.java
new file mode 100644
index 000000000..17817fe1d
--- /dev/null
+++ b/lib/rlock/src/main/java/org/onap/ccsdk/features/lib/rlock/LockHelper.java
@@ -0,0 +1,14 @@
+package org.onap.ccsdk.features.lib.rlock;
+
+import java.util.Collection;
+
+public interface LockHelper {
+
+	void lock(String resourceName, String lockRequester, int lockTimeout /* Seconds */);
+
+	void unlock(String resourceName, boolean force);
+
+	void lock(Collection<String> resourceNameList, String lockRequester, int lockTimeout /* Seconds */);
+
+	void unlock(Collection<String> resourceNameList, boolean force);
+}
diff --git a/lib/rlock/src/main/java/org/onap/ccsdk/features/lib/rlock/LockHelperImpl.java b/lib/rlock/src/main/java/org/onap/ccsdk/features/lib/rlock/LockHelperImpl.java
new file mode 100644
index 000000000..666fb6af5
--- /dev/null
+++ b/lib/rlock/src/main/java/org/onap/ccsdk/features/lib/rlock/LockHelperImpl.java
@@ -0,0 +1,173 @@
+package org.onap.ccsdk.features.lib.rlock;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.Date;
+import java.util.List;
+
+import javax.sql.DataSource;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class LockHelperImpl implements LockHelper {
+
+	private static final Logger log = LoggerFactory.getLogger(LockHelperImpl.class);
+
+	private int retryCount = 20;
+	private int lockWait = 5; // Seconds
+
+	private DataSource dataSource;
+
+	@Override
+	public void lock(String resourceName, String lockRequester, int lockTimeout /* Seconds */) {
+		lock(Collections.singleton(resourceName), lockRequester, lockTimeout);
+	}
+
+	@Override
+	public void unlock(String resourceName, boolean force) {
+		unlock(Collections.singleton(resourceName), force);
+	}
+
+	@Override
+	public void lock(Collection<String> resourceNameList, String lockRequester, int lockTimeout /* Seconds */) {
+		for (int i = 0; true; i++) {
+			try {
+				tryLock(resourceNameList, lockRequester, lockTimeout);
+                log.info("Resources locked: " + resourceNameList);
+				return;
+			} catch (ResourceLockedException e) {
+				if (i > retryCount) {
+					throw e;
+				}
+				try {
+					Thread.sleep(lockWait * 1000L);
+				} catch (InterruptedException ex) {
+				}
+			}
+		}
+	}
+
+	@Override
+	public void unlock(Collection<String> lockNames, boolean force) {
+		if (lockNames == null || lockNames.size() == 0) {
+			return;
+		}
+
+		try (ResourceLockDao resourceLockDao = new ResourceLockDao(dataSource)) {
+			try {
+				for (String name : lockNames) {
+					ResourceLock l = resourceLockDao.getByResourceName(name);
+					if (l != null) {
+						if (force || l.lockCount == 1) {
+							resourceLockDao.delete(l.id);
+						} else {
+							resourceLockDao.decrementLockCount(l.id);
+						}
+					}
+				}
+				resourceLockDao.commit();
+	            log.info("Resources unlocked: " + lockNames);
+			} catch (Exception e) {
+				resourceLockDao.rollback();
+			}
+		}
+	}
+
+	public void tryLock(Collection<String> resourceNameList, String lockRequester, int lockTimeout /* Seconds */) {
+		if (resourceNameList == null || resourceNameList.isEmpty()) {
+			return;
+		}
+
+		lockRequester = generateLockRequester(lockRequester, 100);
+
+		// First check if all requested records are available to lock
+
+		Date now = new Date();
+
+		try (ResourceLockDao resourceLockDao = new ResourceLockDao(dataSource)) {
+			try {
+				List<ResourceLock> dbLockList = new ArrayList<>();
+				List<String> insertLockNameList = new ArrayList<>();
+				for (String name : resourceNameList) {
+					ResourceLock l = resourceLockDao.getByResourceName(name);
+
+					boolean canLock = l == null || now.getTime() > l.expirationTime.getTime() || lockRequester != null && lockRequester.equals(l.lockHolder) || l.lockCount <= 0;
+					if (!canLock) {
+						throw new ResourceLockedException(l.resourceName, l.lockHolder, lockRequester);
+					}
+
+					if (l != null) {
+						if (now.getTime() > l.expirationTime.getTime() || l.lockCount <= 0) {
+							l.lockCount = 0;
+						}
+						dbLockList.add(l);
+					} else {
+						insertLockNameList.add(name);
+					}
+				}
+
+				// Update the lock info in DB
+				for (ResourceLock l : dbLockList) {
+					resourceLockDao.update(l.id, lockRequester, now, new Date(now.getTime() + lockTimeout * 1000), l.lockCount + 1);
+				}
+
+				// Insert records for those that are not yet there
+				for (String lockName : insertLockNameList) {
+					ResourceLock l = new ResourceLock();
+					l.resourceName = lockName;
+					l.lockHolder = lockRequester;
+					l.lockTime = now;
+					l.expirationTime = new Date(now.getTime() + lockTimeout * 1000);
+					l.lockCount = 1;
+
+					try {
+						resourceLockDao.add(l);
+					} catch (Exception e) {
+						throw new ResourceLockedException(l.resourceName, "unknown", lockRequester);
+					}
+				}
+
+				resourceLockDao.commit();
+
+			} catch (Exception e) {
+				resourceLockDao.rollback();
+				throw e;
+			}
+		}
+	}
+
+	private static String generateLockRequester(String name, int maxLength) {
+		if (name == null) {
+			name = "";
+		}
+		int l1 = name.length();
+		String tname = Thread.currentThread().getName();
+		int l2 = tname.length();
+		if (l1 + l2 + 1 > maxLength) {
+			int maxl1 = maxLength / 2;
+			if (l1 > maxl1) {
+				name = name.substring(0, maxl1);
+				l1 = maxl1;
+			}
+			int maxl2 = maxLength - l1 - 1;
+			if (l2 > maxl2) {
+				tname = tname.substring(0, 6) + "..." + tname.substring(l2 - maxl2 + 9);
+			}
+		}
+		return tname + '-' + name;
+	}
+
+	public void setRetryCount(int retryCount) {
+		this.retryCount = retryCount;
+	}
+
+	public void setLockWait(int lockWait) {
+		this.lockWait = lockWait;
+	}
+
+	public void setDataSource(DataSource dataSource) {
+		this.dataSource = dataSource;
+	}
+}
diff --git a/lib/rlock/src/main/java/org/onap/ccsdk/features/lib/rlock/ResourceLock.java b/lib/rlock/src/main/java/org/onap/ccsdk/features/lib/rlock/ResourceLock.java
new file mode 100644
index 000000000..a7e966855
--- /dev/null
+++ b/lib/rlock/src/main/java/org/onap/ccsdk/features/lib/rlock/ResourceLock.java
@@ -0,0 +1,13 @@
+package org.onap.ccsdk.features.lib.rlock;
+
+import java.util.Date;
+
+public class ResourceLock {
+
+	public long id;
+	public String resourceName;
+	public String lockHolder;
+	public int lockCount;
+	public Date lockTime;
+	public Date expirationTime;
+}
diff --git a/lib/rlock/src/main/java/org/onap/ccsdk/features/lib/rlock/ResourceLockDao.java b/lib/rlock/src/main/java/org/onap/ccsdk/features/lib/rlock/ResourceLockDao.java
new file mode 100644
index 000000000..4833bb28e
--- /dev/null
+++ b/lib/rlock/src/main/java/org/onap/ccsdk/features/lib/rlock/ResourceLockDao.java
@@ -0,0 +1,122 @@
+package org.onap.ccsdk.features.lib.rlock;
+
+import java.sql.Connection;
+import java.sql.PreparedStatement;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+import java.sql.Timestamp;
+import java.util.Date;
+
+import javax.sql.DataSource;
+
+public class ResourceLockDao implements AutoCloseable {
+
+	private Connection con;
+
+	public ResourceLockDao(DataSource dataSource) {
+		try {
+			con = dataSource.getConnection();
+			con.setAutoCommit(false);
+		} catch (SQLException e) {
+			throw new RuntimeException("Error getting DB connection: " + e.getMessage(), e);
+		}
+	}
+
+	public void add(ResourceLock l) {
+		String sql = "INSERT INTO RESOURCE_LOCK (resource_name, lock_holder, lock_count, lock_time, expiration_time)\n" + "VALUES (?, ?, ?, ?, ?)";
+
+		try (PreparedStatement ps = con.prepareStatement(sql)) {
+			ps.setString(1, l.resourceName);
+			ps.setString(2, l.lockHolder);
+			ps.setInt(3, l.lockCount);
+			ps.setTimestamp(4, new Timestamp(l.lockTime.getTime()));
+			ps.setTimestamp(5, new Timestamp(l.expirationTime.getTime()));
+			ps.execute();
+		} catch (SQLException e) {
+			throw new RuntimeException("Error adding lock to DB: " + e.getMessage(), e);
+		}
+	}
+
+	public void update(long id, String lockHolder, Date lockTime, Date expirationTime, int lockCount) {
+		String sql = "UPDATE RESOURCE_LOCK SET lock_holder = ?, lock_time = ?, expiration_time = ?, lock_count = ? WHERE resource_lock_id = ?";
+
+		try (PreparedStatement ps = con.prepareStatement(sql)) {
+			ps.setString(1, lockHolder);
+			ps.setTimestamp(2, new Timestamp(lockTime.getTime()));
+			ps.setTimestamp(3, new Timestamp(expirationTime.getTime()));
+			ps.setInt(4, lockCount);
+			ps.setLong(5, id);
+			ps.execute();
+		} catch (SQLException e) {
+			throw new RuntimeException("Error updating lock in DB: " + e.getMessage(), e);
+		}
+	}
+
+	public ResourceLock getByResourceName(String resourceName) {
+		String sql = "SELECT * FROM RESOURCE_LOCK WHERE resource_name = ?";
+
+		try (PreparedStatement ps = con.prepareStatement(sql)) {
+			ps.setString(1, resourceName);
+			try (ResultSet rs = ps.executeQuery()) {
+				if (rs.next()) {
+					ResourceLock rl = new ResourceLock();
+					rl.id = rs.getLong("resource_lock_id");
+					rl.resourceName = rs.getString("resource_name");
+					rl.lockHolder = rs.getString("lock_holder");
+					rl.lockCount = rs.getInt("lock_count");
+					rl.lockTime = rs.getTimestamp("lock_time");
+					rl.expirationTime = rs.getTimestamp("expiration_time");
+					return rl;
+				}
+				return null;
+			}
+		} catch (SQLException e) {
+			throw new RuntimeException("Error reading lock from DB: " + e.getMessage(), e);
+		}
+	}
+
+	public void delete(long id) {
+		String sql = "DELETE FROM RESOURCE_LOCK WHERE resource_lock_id = ?";
+
+		try (PreparedStatement ps = con.prepareStatement(sql)) {
+			ps.setLong(1, id);
+			ps.execute();
+		} catch (SQLException e) {
+			throw new RuntimeException("Error deleting lock from DB: " + e.getMessage(), e);
+		}
+	}
+
+	public void decrementLockCount(long id) {
+		String sql = "UPDATE RESOURCE_LOCK SET lock_count = lock_count - 1 WHERE resource_lock_id = ?";
+
+		try (PreparedStatement ps = con.prepareStatement(sql)) {
+			ps.setLong(1, id);
+			ps.execute();
+		} catch (SQLException e) {
+			throw new RuntimeException("Error updating lock count in DB: " + e.getMessage(), e);
+		}
+	}
+
+	public void commit() {
+		try {
+			con.commit();
+		} catch (SQLException e) {
+			throw new RuntimeException("Error committing DB connection: " + e.getMessage(), e);
+		}
+	}
+
+	public void rollback() {
+		try {
+			con.rollback();
+		} catch (SQLException e) {
+		}
+	}
+
+	@Override
+	public void close() {
+		try {
+			con.close();
+		} catch (SQLException e) {
+		}
+	}
+}
diff --git a/lib/rlock/src/main/java/org/onap/ccsdk/features/lib/rlock/ResourceLockedException.java b/lib/rlock/src/main/java/org/onap/ccsdk/features/lib/rlock/ResourceLockedException.java
new file mode 100644
index 000000000..7c8cfa122
--- /dev/null
+++ b/lib/rlock/src/main/java/org/onap/ccsdk/features/lib/rlock/ResourceLockedException.java
@@ -0,0 +1,20 @@
+package org.onap.ccsdk.features.lib.rlock;
+
+public class ResourceLockedException extends RuntimeException {
+
+	private static final long serialVersionUID = 1L;
+
+	private String lockName, lockHolder, lockRequester;
+
+	public ResourceLockedException(String lockName, String lockHolder, String lockRequester) {
+		this.lockName = lockName;
+		this.lockHolder = lockHolder;
+		this.lockRequester = lockRequester;
+	}
+
+	@Override
+	public String getMessage() {
+		return "Failed to lock [" + lockName + "] for [" + lockRequester + "]. Currently locked by [" + lockHolder +
+		        "].";
+	}
+}
diff --git a/lib/rlock/src/main/java/org/onap/ccsdk/features/lib/rlock/SynchronizedFunction.java b/lib/rlock/src/main/java/org/onap/ccsdk/features/lib/rlock/SynchronizedFunction.java
new file mode 100644
index 000000000..ff25e16f0
--- /dev/null
+++ b/lib/rlock/src/main/java/org/onap/ccsdk/features/lib/rlock/SynchronizedFunction.java
@@ -0,0 +1,35 @@
+package org.onap.ccsdk.features.lib.rlock;
+
+import java.util.Collection;
+import java.util.HashSet;
+import java.util.Set;
+
+public abstract class SynchronizedFunction {
+
+	private Set<String> synchset;
+	private String lockRequester;
+	private int lockTimeout; // Seconds
+	private LockHelper lockHelper;
+
+	protected SynchronizedFunction(LockHelper lockHelper, Collection<String> synchset, int lockTimeout) {
+		this.lockHelper = lockHelper;
+		this.synchset = new HashSet<String>(synchset);
+		this.lockRequester = generateLockRequester();
+		this.lockTimeout = lockTimeout;
+	}
+
+	protected abstract void _exec();
+
+	public void exec() {
+		lockHelper.lock(synchset, lockRequester, lockTimeout);
+		try {
+			_exec();
+		} finally {
+			lockHelper.unlock(synchset, true);
+		}
+	}
+
+	private static String generateLockRequester() {
+		return "SynchronizedFunction-" + (int) (Math.random() * 1000000);
+	}
+}