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.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;
+import com.datastax.driver.core.Session;
+import com.datastax.driver.extras.codecs.enums.EnumNameCodec;
/*
* This is the lock store that is built on top of Cassandra that is used by MUSIC to maintain lock state.
private String createTime;
private String acquireTime;
private LockType locktype;
- public LockObject(boolean isLockOwner, String lockRef, String createTime, String acquireTime, 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 setLocktype(LockType locktype) {
this.locktype = locktype;
}
+ public String getOwner() {
+ return owner;
+ }
+ public void setOwner(String owner) {
+ this.owner = owner;
+ }
}
/**
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, "
- + "writeLock boolean, PRIMARY KEY ((key), lockReference) ) "
+ + "lockType text, owner text, PRIMARY KEY ((key), lockReference) ) "
+ "WITH CLUSTERING ORDER BY (lockReference ASC);";
PreparedQueryObject queryObject = new PreparedQueryObject();
* @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) throws MusicServiceException, MusicQueryException, MusicLockingException {
- return genLockRefandEnQueue(keyspace, table, lockName, locktype, 0);
+ 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, int count) throws MusicServiceException, MusicQueryException, MusicLockingException {
+ 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=?;";
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, writeLock) VALUES (?,?,?,?,?) IF NOT EXISTS; APPLY BATCH;";
+ "(key, lockReference, createTime, acquireTime, lockType, owner) VALUES (?,?,?,?,?,?) IF NOT EXISTS; APPLY BATCH;";
queryObject.addValue(lockRef);
queryObject.addValue(lockName);
queryObject.addValue(lockRef);
queryObject.addValue(String.valueOf(lockEpochMillis));
queryObject.addValue("0");
- queryObject.addValue(locktype==LockType.WRITE ? true : false );
+ queryObject.addValue(locktype);
+ queryObject.addValue(owner);
queryObject.appendQueryString(insQuery);
boolean pResult = dsHandle.executePut(queryObject, "critical");
if (!pResult) {// couldn't create lock ref, retry
logger.warn(EELFLoggerDelegate.applicationLogger, "Unable to create lock reference");
throw new MusicLockingException("Unable to create lock reference");
}
- return genLockRefandEnQueue(keyspace, table, lockName, locktype, count);
+ 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
ResultSet results = dsHandle.executeOneConsistencyGet(queryObject);
Row row = results.one();
if (row == null || row.isNull("lockReference")) {
- return new LockObject(false, null, null, null, null);
+ 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.getBool("writeLock") ? LockType.WRITE : LockType.READ;
+ LockType locktype = row.get("lockType", LockType.class);
+ String owner = row.getString("owner");
- return new LockObject(true, lockReference, createTime, acquireTime, locktype);
+ 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);
-
- List<String> lockHolders = new ArrayList<>();
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) {
- String lockReference = "" + row.getLong("lockReference");
- if (row.getBool("writeLock")) {
+ 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);
+ lockHolders.add(lockReference.toString());
break;
} else {
break;
}
}
// read lock
- lockHolders.add(lockReference);
+ lockHolders.add(lockReference.toString());
topOfQueue = false;
+ lockReference.delete(0,lockReference.length());
}
return lockHolders;
}
boolean topOfQueue = true;
for (Row row : rs) {
- String lockReference = "" + row.getLong("lockReference");
- if (row.getBool("writeLock")) {
+ String lockReference = "" + row.getLong("lockReference");
+ if (row.get("lockType", LockType.class)==LockType.WRITE) {
if (topOfQueue && lockRef.equals(lockReference)) {
- return true;
+ return true;
} else {
- return false;
+ return false;
}
}
if (lockRef.equals(lockReference)) {
- return true;
+ return true;
}
topOfQueue = false;
}
String lockReference = "" + row.getLong("lockReference");
String createTime = row.getString("createTime");
String acquireTime = row.getString("acquireTime");
- LockType locktype = row.getBool("writeLock") ? LockType.WRITE : LockType.READ;
+ 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);
+ return new LockObject(isLockOwner, lockReference, createTime, acquireTime, locktype, owner);
}
}
- public void updateLockAcquireTime(String keyspace, String table, String key, String lockReference)
- throws MusicServiceException, MusicQueryException {
+ public void updateLockAcquireTime(String keyspace, String table, String key, String lockReference) {
table = table_prepend_name + table;
- PreparedQueryObject queryObject = new PreparedQueryObject();
Long lockReferenceL = Long.parseLong(lockReference);
String updateQuery = "update " + keyspace + "." + table + " set acquireTime='" + System.currentTimeMillis()
+ "' where key='" + key + "' AND lockReference = " + lockReferenceL + " IF EXISTS;";
- queryObject.appendQueryString(updateQuery);
- dsHandle.executePut(queryObject, "eventual");
+ //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 = new DeadlockDetectionUtil();
+
+ ResultSet rs = dsHandle.executeQuorumConsistencyGet(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;
+ }
+
+ public List<String> getAllLocksForOwner(String ownerId, String keyspace, String table) throws MusicServiceException, MusicQueryException {
+ List<String> toRet = new ArrayList<String>();
+ 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 MusicLockingException, 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);
+ }
+
+
+
}
Code Review / music.git / blobdiff