diff options
Diffstat (limited to 'music-core/src/main/java/org/onap/music/lockingservice/cassandra/CassaLockStore.java')
| -rw-r--r-- | music-core/src/main/java/org/onap/music/lockingservice/cassandra/CassaLockStore.java | 613 |
1 files changed, 613 insertions, 0 deletions
diff --git a/music-core/src/main/java/org/onap/music/lockingservice/cassandra/CassaLockStore.java b/music-core/src/main/java/org/onap/music/lockingservice/cassandra/CassaLockStore.java new file mode 100644 index 00000000..9a69a9ba --- /dev/null +++ b/music-core/src/main/java/org/onap/music/lockingservice/cassandra/CassaLockStore.java @@ -0,0 +1,613 @@ +/* + * ============LICENSE_START========================================== + * org.onap.music + * =================================================================== + * Copyright (c) 2017 AT&T Intellectual Property + * Modifications Copyright (C) 2019 IBM. + * =================================================================== + * 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. + * + * ============LICENSE_END============================================= + * ==================================================================== + */ + +package org.onap.music.lockingservice.cassandra; + +import java.util.ArrayList; +import java.util.Iterator; +import java.util.List; + +import org.onap.music.datastore.MusicDataStore; +import org.onap.music.datastore.PreparedQueryObject; +import org.onap.music.eelf.logging.EELFLoggerDelegate; +import org.onap.music.exceptions.MusicLockingException; +import org.onap.music.exceptions.MusicQueryException; +import org.onap.music.exceptions.MusicServiceException; +import org.onap.music.main.DeadlockDetectionUtil; +import org.onap.music.main.DeadlockDetectionUtil.OwnershipType; +import org.onap.music.main.MusicUtil; +import org.onap.music.main.ResultType; +import org.onap.music.main.ReturnType; +import com.datastax.driver.core.ResultSet; +import com.datastax.driver.core.Row; + +/* + * This is the lock store that is built on top of Cassandra that is used by MUSIC to maintain lock state. + */ + +public class CassaLockStore { + + private EELFLoggerDelegate logger = EELFLoggerDelegate.getLogger(CassaLockStore.class); + public static final String table_prepend_name = "lockQ_"; + private MusicDataStore dsHandle; + + public CassaLockStore() { + dsHandle = new MusicDataStore(); + } + + public CassaLockStore(MusicDataStore dsHandle) { + this.dsHandle=dsHandle; + } + public class LockObject{ + private boolean isLockOwner; + private String lockRef; + private String createTime; + private String acquireTime; + private LockType locktype; + // Owner is the self-declared client which "owns" this row. It is used for deadlock detection. It is not (directly) related to isLockOwner. + private String owner; + public LockObject(boolean isLockOwner, String lockRef, String createTime, String acquireTime, LockType locktype, String owner) { + this.setIsLockOwner(isLockOwner); + this.setLockRef(lockRef); + this.setAcquireTime(acquireTime); + this.setCreateTime(createTime); + this.setLocktype(locktype); + this.setOwner(owner); + } + public boolean getIsLockOwner() { + return isLockOwner; + } + public void setIsLockOwner(boolean isLockOwner) { + this.isLockOwner = isLockOwner; + } + public String getAcquireTime() { + return acquireTime; + } + public void setAcquireTime(String acquireTime) { + this.acquireTime = acquireTime; + } + public String getCreateTime() { + return createTime; + } + public void setCreateTime(String createTime) { + this.createTime = createTime; + } + public String getLockRef() { + return lockRef; + } + public void setLockRef(String lockRef) { + this.lockRef = lockRef; + } + public LockType getLocktype() { + return locktype; + } + public void setLocktype(LockType locktype) { + this.locktype = locktype; + } + public String getOwner() { + return owner; + } + public void setOwner(String owner) { + this.owner = owner; + } + } + + /** + * + * This method creates a shadow locking table for every main table in Cassandra. This table tracks all information regarding locks. + * @param keyspace of the application. + * @param table of the application. + * @return true if the operation was successful. + * @throws MusicServiceException + * @throws MusicQueryException + */ + public boolean createLockQueue(String keyspace, String table) throws MusicServiceException, MusicQueryException { + logger.info(EELFLoggerDelegate.applicationLogger, + "Create lock queue/table for " + keyspace+"."+table); + table = table_prepend_name+table; + String tabQuery = "CREATE TABLE IF NOT EXISTS "+keyspace+"."+table + + " ( key text, lockReference bigint, createTime text, acquireTime text, guard bigint static, " + + "lockType text, leasePeriodTime bigint, owner text, PRIMARY KEY ((key), lockReference) ) " + + "WITH CLUSTERING ORDER BY (lockReference ASC);"; + PreparedQueryObject queryObject = new PreparedQueryObject(); + + queryObject.appendQueryString(tabQuery); + boolean result; + result = dsHandle.executePut(queryObject, "eventual"); + return result; + } + + /** + * This method creates a lock reference for each invocation. The lock references are monotonically increasing timestamps. + * @param keyspace of the locks. + * @param table of the locks. + * @param lockName is the primary key of the lock table + * @param lockType is the type of lock (read/write) + * @param owner is the owner of the lock (optional, for deadlock detection) + * @return the UUID lock reference. + * @throws MusicServiceException + * @throws MusicQueryException + */ + public String genLockRefandEnQueue(String keyspace, String table, String lockName, LockType locktype, String owner) throws MusicServiceException, MusicQueryException, MusicLockingException { + return genLockRefandEnQueue(keyspace, table, lockName, locktype, owner, 0); + } + + private String genLockRefandEnQueue(String keyspace, String table, String lockName, LockType locktype, String owner, int count) throws MusicServiceException, MusicQueryException, MusicLockingException { + logger.info(EELFLoggerDelegate.applicationLogger, + "Create " + locktype + " lock reference for " + keyspace + "." + table + "." + lockName); + String lockTable =""; + lockTable = table_prepend_name+table; + + PreparedQueryObject queryObject = new PreparedQueryObject(); + String selectQuery = "SELECT guard FROM " + keyspace + "." + lockTable + " WHERE key=?;"; + + queryObject.addValue(lockName); + queryObject.appendQueryString(selectQuery); + ResultSet gqResult = dsHandle.executeOneConsistencyGet(queryObject); + List<Row> latestGuardRow = gqResult.all(); + + long prevGuard = 0; + long lockRef = 1; + if (!latestGuardRow.isEmpty()) { + prevGuard = latestGuardRow.get(0).getLong(0); + lockRef = prevGuard + 1; + } + + long lockEpochMillis = System.currentTimeMillis(); + + logger.info(EELFLoggerDelegate.applicationLogger, + "Created lock reference for " + keyspace + "." + lockTable + "." + lockName + ":" + lockRef); + + queryObject = new PreparedQueryObject(); + + String insQuery = "BEGIN BATCH" + + " UPDATE " + keyspace + "." + lockTable + + " SET guard=? WHERE key=? IF guard = " + (prevGuard == 0 ? "NULL" : "?") +";" + + " INSERT INTO " + keyspace + "." + lockTable + + "(key, lockReference, createTime, acquireTime, lockType, owner) VALUES (?,?,?,?,?,?) IF NOT EXISTS; APPLY BATCH;"; + + queryObject.addValue(lockRef); + queryObject.addValue(lockName); + if (prevGuard != 0) + queryObject.addValue(prevGuard); + + queryObject.addValue(lockName); + queryObject.addValue(lockRef); + queryObject.addValue(String.valueOf(lockEpochMillis)); + queryObject.addValue("0"); + queryObject.addValue(locktype); + queryObject.addValue(owner); + queryObject.appendQueryString(insQuery); + boolean pResult = dsHandle.executePut(queryObject, "critical"); + if (!pResult) {// couldn't create lock ref, retry + count++; + if (count > MusicUtil.getRetryCount()) { + logger.warn(EELFLoggerDelegate.applicationLogger, "Unable to create lock reference"); + throw new MusicLockingException("Unable to create lock reference"); + } + return genLockRefandEnQueue(keyspace, table, lockName, locktype, owner, count); + } + return "$" + keyspace + "." + table + "." + lockName + "$" + String.valueOf(lockRef); + } + + /** + * Returns a result set containing the list of clients waiting for a particular lock + * + * @param keyspace + * @param table + * @param key + * @return list of lockrefs in the queue + * @throws MusicServiceException + * @throws MusicQueryException + */ + public List<String> getLockQueue(String keyspace, String table, String key) + throws MusicServiceException, MusicQueryException { + logger.info(EELFLoggerDelegate.applicationLogger, + "Getting the queue for " + keyspace + "." + table + "." + key); + table = table_prepend_name + table; + String selectQuery = "select * from " + keyspace + "." + table + " where key='" + key + "';"; + PreparedQueryObject queryObject = new PreparedQueryObject(); + queryObject.appendQueryString(selectQuery); + ResultSet rs = dsHandle.executeOneConsistencyGet(queryObject); + ArrayList<String> lockQueue = new ArrayList<>(); + for (Row row : rs) { + lockQueue.add(Long.toString(row.getLong("lockReference"))); + } + return lockQueue; + } + + + /** + * Returns a result set containing the list of clients waiting for a particular lock + * + * @param keyspace + * @param table + * @param key + * @return size of lockrefs queue + * @throws MusicServiceException + * @throws MusicQueryException + */ + public long getLockQueueSize(String keyspace, String table, String key) + throws MusicServiceException, MusicQueryException { + logger.info(EELFLoggerDelegate.applicationLogger, + "Getting the queue size for " + keyspace + "." + table + "." + key); + table = table_prepend_name + table; + String selectQuery = "select count(*) from " + keyspace + "." + table + " where key='" + key + "';"; + PreparedQueryObject queryObject = new PreparedQueryObject(); + queryObject.appendQueryString(selectQuery); + ResultSet rs = dsHandle.executeOneConsistencyGet(queryObject); + return rs.one().getLong("count"); + } + + + /** + * This method returns the top of lock table/queue for the key. + * + * @param keyspace of the application. + * @param table of the application. + * @param key is the primary key of the application table + * @return the UUID lock reference. Returns LockObject.isLockOwner=false if there is no owner or the + * lock doesn't exist + * @throws MusicServiceException + * @throws MusicQueryException + */ + public LockObject peekLockQueue(String keyspace, String table, String key) + throws MusicServiceException, MusicQueryException { + logger.info(EELFLoggerDelegate.applicationLogger, + "Peek in lock table for " + keyspace + "." + table + "." + key); + table = table_prepend_name + table; + String selectQuery = "select * from " + keyspace + "." + table + " where key='" + key + "' LIMIT 1;"; + PreparedQueryObject queryObject = new PreparedQueryObject(); + queryObject.appendQueryString(selectQuery); + ResultSet results = dsHandle.executeOneConsistencyGet(queryObject); + Row row = results.one(); + if (row == null || row.isNull("lockReference")) { + return new LockObject(false, null, null, null, null, null); + } + String lockReference = "" + row.getLong("lockReference"); + String createTime = row.getString("createTime"); + String acquireTime = row.getString("acquireTime"); + LockType locktype = row.get("lockType", LockType.class); + String owner = row.getString("owner"); + + return new LockObject(true, lockReference, createTime, acquireTime, locktype, owner); + } + + public List<String> getCurrentLockHolders(String keyspace, String table, String key) + throws MusicServiceException, MusicQueryException { + logger.info(EELFLoggerDelegate.applicationLogger, + "Getting lockholders in lock table for " + keyspace + "." + table + "." + key); + String origTable = table; + table = table_prepend_name + table; + String selectQuery = "select * from " + keyspace + "." + table + " where key=?;"; + List<String> lockHolders = new ArrayList<>(); + PreparedQueryObject queryObject = new PreparedQueryObject(); + queryObject.appendQueryString(selectQuery); + queryObject.addValue(key); + ResultSet rs = dsHandle.executeOneConsistencyGet(queryObject); + boolean topOfQueue = true; + StringBuilder lock = new StringBuilder(). + append("$").append(keyspace).append(".").append(origTable). + append(".").append(key).append("$"); + StringBuilder lockReference = new StringBuilder(); + for (Row row : rs) { + if ( row.isNull("lockReference") ) { + return lockHolders; + } + lockReference.append(lock).append(row.getLong("lockReference")); + if (row.get("lockType", LockType.class)!=LockType.WRITE) { + if (topOfQueue) { + lockHolders.add(lockReference.toString()); + break; + } else { + break; + } + } + // read lock + lockHolders.add(lockReference.toString()); + + topOfQueue = false; + lockReference.delete(0,lockReference.length()); + } + return lockHolders; + } + + /** + * Determine if the lock is a valid current lock holder. + * + * @param keyspace + * @param table + * @param key + * @param lockRef + * @return true if lockRef is a lock owner of key + * @throws MusicServiceException + * @throws MusicQueryException + */ + public boolean isLockOwner(String keyspace, String table, String key, String lockRef) + throws MusicServiceException, MusicQueryException { + logger.info(EELFLoggerDelegate.applicationLogger, + "Checking in lock table for " + keyspace + "." + table + "." + key); + table = table_prepend_name + table; + String selectQuery = + "select * from " + keyspace + "." + table + " where key=?;"; + PreparedQueryObject queryObject = new PreparedQueryObject(); + queryObject.appendQueryString(selectQuery); + queryObject.addValue(key); + ResultSet rs = dsHandle.executeOneConsistencyGet(queryObject); + + boolean topOfQueue = true; + for (Row row : rs) { + String lockReference = "" + row.getLong("lockReference"); + if (row.get("lockType", LockType.class)==LockType.WRITE) { + if (topOfQueue && lockRef.equals(lockReference)) { + return true; + } else { + return false; + } + } + if (lockRef.equals(lockReference)) { + return true; + } + topOfQueue = false; + } + logger.info(EELFLoggerDelegate.applicationLogger, "Could not find " + lockRef + + " in the lock queue. It has expired and no longer exists."); + return false; + } + + /** + * Determine if the lock is a valid current lock holder. + * + * @param keyspace + * @param table + * @param key + * @param lockRef + * @return true if lockRef is a lock owner of key + * @throws MusicServiceException + * @throws MusicQueryException + */ + public LockObject getLockInfo(String keyspace, String table, String key, String lockRef) + throws MusicServiceException, MusicQueryException { + logger.info(EELFLoggerDelegate.applicationLogger, + "Checking in lock table for " + keyspace + "." + table + "." + key); + String lockQ_table = table_prepend_name + table; + String selectQuery = + "select * from " + keyspace + "." + lockQ_table + " where key=? and lockReference=?;"; + PreparedQueryObject queryObject = new PreparedQueryObject(); + queryObject.appendQueryString(selectQuery); + queryObject.addValue(key); + queryObject.addValue(Long.parseLong(lockRef)); + ResultSet rs = dsHandle.executeOneConsistencyGet(queryObject); + Row row = rs.one(); + if (row == null || row.isNull("lockReference")) { + return null; + } + + String lockReference = "" + row.getLong("lockReference"); + String createTime = row.getString("createTime"); + String acquireTime = row.getString("acquireTime"); + LockType locktype = row.get("lockType", LockType.class); + boolean isLockOwner = isLockOwner(keyspace, table, key, lockRef); + String owner = row.getString("owner"); + + return new LockObject(isLockOwner, lockReference, createTime, acquireTime, locktype, owner); + } + + + + /** + * This method removes the lock ref from the lock table/queue for the key. + * + * @param keyspace of the application. + * @param table of the application. + * @param key is the primary key of the application table + * @param lockReference the lock reference that needs to be dequeued. + * @throws MusicServiceException + * @throws MusicQueryException + * @throws MusicLockingException + */ + public void deQueueLockRef(String keyspace, String table, String key, String lockReference, int n) + throws MusicServiceException, MusicQueryException, MusicLockingException { + String prependTable = table_prepend_name + table; + PreparedQueryObject queryObject = new PreparedQueryObject(); + Long lockReferenceL = Long.parseLong(lockReference.substring(lockReference.lastIndexOf("$") + 1)); + String deleteQuery = "delete from " + keyspace + "." + prependTable + " where key='" + key + + "' AND lockReference =" + lockReferenceL + " IF EXISTS;"; + queryObject.appendQueryString(deleteQuery); + logger.info(EELFLoggerDelegate.applicationLogger, "Removing lock for key: "+key+ " and reference: "+lockReference); + try { + dsHandle.executePut(queryObject, "critical"); + logger.info(EELFLoggerDelegate.applicationLogger, + "Lock removed for key: " + key + " and reference: " + lockReference); + } catch (MusicServiceException ex) { + logger.error(logger, ex.getMessage(), ex); + logger.error(EELFLoggerDelegate.applicationLogger, + "Exception while deQueueLockRef for lockname: " + key + " reference:" + lockReference); + if (n > 1) { + logger.info(EELFLoggerDelegate.applicationLogger, "Trying again..."); + deQueueLockRef(keyspace, table, key, lockReference, n - 1); + } else { + logger.error(EELFLoggerDelegate.applicationLogger, + "deQueueLockRef failed for lockname: " + key + " reference:" + lockReference); + logger.error(logger, ex.getMessage(), ex); + throw new MusicLockingException("Error while deQueueLockRef: " + ex.getMessage()); + } + } + } + + + public void updateLockAcquireTime(String keyspace, String table, String key, String lockReference) { + table = table_prepend_name + table; + Long lockReferenceL = Long.parseLong(lockReference); + String updateQuery = "update " + keyspace + "." + table + " set acquireTime='" + System.currentTimeMillis() + + "' where key='" + key + "' AND lockReference = " + lockReferenceL + " IF EXISTS;"; + + //cannot use executePut because we need to ignore music timestamp adjustments for lock store + dsHandle.getSession().execute(updateQuery); + } + + public boolean checkForDeadlock(String keyspace, String table, String lockName, LockType locktype, String owner, boolean forAcquire) throws MusicServiceException, MusicQueryException { + if (locktype.equals(LockType.READ)) + return false; + if (owner==null || owner.length()==0) + return false; + + String lockTable = table_prepend_name + table; + PreparedQueryObject queryObject = new PreparedQueryObject(); + queryObject.appendQueryString("SELECT key, acquiretime, owner FROM " + keyspace + "." + lockTable); + queryObject.appendQueryString(" WHERE lockType = ? ALLOW FILTERING"); + queryObject.addValue(LockType.WRITE); + + DeadlockDetectionUtil ddu = getDeadlockDetectionUtil(); + + ResultSet rs = dsHandle.executeLocalQuorumConsistencyGet(queryObject); + logger.debug("rs has " + rs.getAvailableWithoutFetching() + (rs.isFullyFetched()?"":" (or more!)") ); + Iterator<Row> it = rs.iterator(); + while (it.hasNext()) { + Row row = it.next(); + logger.debug("key = " + row.getString("key") + ", time = " + row.getString("acquiretime") + ", owner = " + row.getString("owner") ); + ddu.setExisting(row.getString("key"), row.getString("owner"), ("0".equals(row.getString("acquiretime")))?OwnershipType.CREATED:OwnershipType.ACQUIRED); + } + boolean deadlock = ddu.checkForDeadlock(lockName, owner, forAcquire?OwnershipType.ACQUIRED:OwnershipType.CREATED); + if (deadlock) + logger.warn("Deadlock detected when " + owner + " tried to create lock on " + keyspace + "." + lockTable + "." + lockName); + return deadlock; + } + + /** + * This is used for testing purpose + * @return new DeadlockDetectionUtil object + */ + DeadlockDetectionUtil getDeadlockDetectionUtil() { + return new DeadlockDetectionUtil(); + } + + public List<String> getAllLocksForOwner(String ownerId, String keyspace, String table) throws MusicServiceException, MusicQueryException { + List<String> toRet = new ArrayList<>(); + String lockTable = table_prepend_name + table; + PreparedQueryObject queryObject = new PreparedQueryObject(); + queryObject.appendQueryString("SELECT key, lockreference FROM " + keyspace + "." + lockTable); + queryObject.appendQueryString(" WHERE owner = '" + ownerId + "' ALLOW FILTERING"); + + ResultSet rs = dsHandle.executeQuorumConsistencyGet(queryObject); + Iterator<Row> it = rs.iterator(); + while (it.hasNext()) { + Row row = it.next(); + toRet.add(row.getString("key") + "$" + row.getLong("lockreference")); + } + return toRet; + } + + public ReturnType promoteLock(String keyspace, String table, String key, String lockRef) + throws MusicServiceException, MusicQueryException { + String lockqtable = table_prepend_name + table; + String selectQuery = "select * from " + keyspace + "." + lockqtable + " where key=?;"; + + PreparedQueryObject queryObject = new PreparedQueryObject(); + queryObject.appendQueryString(selectQuery); + queryObject.addValue(key); + ResultSet rs = dsHandle.executeOneConsistencyGet(queryObject); + + long refToPromote = Long.parseLong(lockRef); + + boolean topOfQueue = true; + boolean readBlock = false; + boolean seenLockToPromote = false; + boolean promotionOngoing = false; + long readBlockStart = 0; + long readBlockEnd = 0; + + + for (Row row : rs) { + long ref = row.getLong("lockreference"); + LockType lockType = row.get("lockType", LockType.class); + + if (refToPromote==ref) { + if (promotionOngoing) { + return new ReturnType(ResultType.FAILURE, "Can't promote, already promoting another lockref."); + } + seenLockToPromote = true; + if (!topOfQueue) { + readBlockStart = ref; + readBlockEnd = ref; + break; + } + } else if (!seenLockToPromote && refToPromote<ref) { + return new ReturnType(ResultType.FAILURE, "Lockref does not exist."); + } + + if (lockType==LockType.READ || lockType==LockType.PROMOTING) { + if (!readBlock) { + readBlockStart = ref; + readBlock = true; + } + if (readBlock) { + readBlockEnd = ref; + } + if (lockType==LockType.PROMOTING) { + promotionOngoing = true; + } + } + + if (lockType==LockType.WRITE) { + if (refToPromote==ref) { + return new ReturnType(ResultType.FAILURE, "Lockref is already write."); + } + if (readBlock) { + readBlock = false; + promotionOngoing = false; + if (seenLockToPromote) { + break; + } + //can no longer be lock holder after this + topOfQueue = false; + } + } + } + + if (readBlockStart<=refToPromote && refToPromote<=readBlockEnd) { + if (readBlockStart==refToPromote && refToPromote==readBlockEnd) { + promoteLockTo(keyspace, lockqtable, key, lockRef, LockType.WRITE); + return new ReturnType(ResultType.SUCCESS, "Lock has successfully been upgraded."); + } + promoteLockTo(keyspace, lockqtable, key, lockRef, LockType.PROMOTING); + return new ReturnType(ResultType.FAILURE, "Your lock upgrade is in progress. Check again to see if successful."); + } + + //shouldn't reach here? + return new ReturnType(ResultType.FAILURE,"Promotion failed."); + } + + private void promoteLockTo(String keyspace, String table, String key, String lockRef, LockType newLockType) + throws MusicServiceException, MusicQueryException { + PreparedQueryObject queryObject = + new PreparedQueryObject("UPDATE " + keyspace + "." + table + " SET lockType=? WHERE key='" + key + + "' AND lockReference = " + lockRef + " IF EXISTS;", newLockType); + + //cannot use executePut because we need to ignore music timestamp adjustments for lock store + dsHandle.executePut(queryObject, MusicUtil.QUORUM); + } + + + +} |