package org.apache.helix.josql;
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.
*/
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.apache.helix.HelixDataAccessor;
import org.apache.helix.HelixException;
import org.apache.helix.HelixManager;
import org.apache.helix.HelixProperty;
import org.apache.helix.PropertyType;
import org.apache.helix.ZNRecord;
import org.apache.helix.ConfigScope.ConfigScopeProperty;
import org.apache.helix.PropertyKey.Builder;
import org.apache.helix.model.LiveInstance.LiveInstanceProperty;
import org.apache.log4j.Logger;
import org.josql.Query;
import org.josql.QueryExecutionException;
import org.josql.QueryParseException;
import org.josql.QueryResults;
public class ClusterJosqlQueryProcessor
{
public static final String PARTITIONS = "PARTITIONS";
public static final String FLATTABLE = ".Table";
HelixManager _manager;
private static Logger _logger = Logger.getLogger(ClusterJosqlQueryProcessor.class);
public ClusterJosqlQueryProcessor(HelixManager manager)
{
_manager = manager;
}
String parseFromTarget(String sql)
{
// We need to find out the "FROM" target, and replace it with liveInstances
// / partitions etc
int fromIndex = sql.indexOf("FROM");
if (fromIndex == -1)
{
throw new HelixException("Query must contain FROM target. Query: " + sql);
}
// Per JoSql, select FROM <target> the target must be a object class that
// corresponds to a "table row"
// In out case, the row is always a ZNRecord
int nextSpace = sql.indexOf(" ", fromIndex);
while (sql.charAt(nextSpace) == ' ')
{
nextSpace++;
}
int nextnextSpace = sql.indexOf(" ", nextSpace);
if (nextnextSpace == -1)
{
nextnextSpace = sql.length();
}
String fromTarget = sql.substring(nextSpace, nextnextSpace).trim();
if (fromTarget.length() == 0)
{
throw new HelixException("FROM target in the query cannot be empty. Query: " + sql);
}
return fromTarget;
}
public List<Object> runJoSqlQuery(String josql, Map<String, Object> bindVariables,
List<Object> additionalFunctionHandlers, List queryTarget) throws QueryParseException,
QueryExecutionException
{
Query josqlQuery = prepareQuery(bindVariables, additionalFunctionHandlers);
josqlQuery.parse(josql);
QueryResults qr = josqlQuery.execute(queryTarget);
return qr.getResults();
}
Query prepareQuery(Map<String, Object> bindVariables, List<Object> additionalFunctionHandlers)
{
// DataAccessor accessor = _manager.getDataAccessor();
HelixDataAccessor accessor = _manager.getHelixDataAccessor();
// Get all the ZNRecords in the cluster and set them as bind variables
Builder keyBuilder = accessor.keyBuilder();
// List<ZNRecord> instanceConfigs = accessor.getChildValues(PropertyType.CONFIGS,
// ConfigScopeProperty.PARTICIPANT.toString());
List<ZNRecord> instanceConfigs = HelixProperty.convertToList(accessor.getChildValues(keyBuilder.instanceConfigs()));
List<ZNRecord> liveInstances = HelixProperty.convertToList(accessor.getChildValues(keyBuilder.liveInstances()));
List<ZNRecord> stateModelDefs = HelixProperty.convertToList(accessor.getChildValues(keyBuilder.stateModelDefs()));
// Idealstates are stored in a map from resource name to idealState ZNRecord
List<ZNRecord> idealStateList = HelixProperty.convertToList(accessor.getChildValues(keyBuilder.idealStates()));
Map<String, ZNRecord> idealStatesMap = new HashMap<String, ZNRecord>();
for (ZNRecord idealState : idealStateList)
{
idealStatesMap.put(idealState.getId(), idealState);
}
// Make up the partition list: for selecting partitions
List<ZNRecord> partitions = new ArrayList<ZNRecord>();
for (ZNRecord idealState : idealStateList)
{
for (String partitionName : idealState.getMapFields().keySet())
{
partitions.add(new ZNRecord(partitionName));
}
}
List<ZNRecord> externalViewList = HelixProperty.convertToList(accessor.getChildValues(keyBuilder.externalViews()));
// ExternalViews are stored in a map from resource name to idealState
// ZNRecord
Map<String, ZNRecord> externalViewMap = new HashMap<String, ZNRecord>();
for (ZNRecord externalView : externalViewList)
{
externalViewMap.put(externalView.getId(), externalView);
}
// Map from instance name to a map from resource to current state ZNRecord
Map<String, Map<String, ZNRecord>> currentStatesMap = new HashMap<String, Map<String, ZNRecord>>();
// Map from instance name to a list of combined flat ZNRecordRow
Map<String, List<ZNRecordRow>> flatCurrentStateMap = new HashMap<String, List<ZNRecordRow>>();
for (ZNRecord instance : liveInstances)
{
String host = instance.getId();
String sessionId = instance.getSimpleField(LiveInstanceProperty.SESSION_ID.toString());
Map<String, ZNRecord> currentStates = new HashMap<String, ZNRecord>();
List<ZNRecord> instanceCurrentStateList = new ArrayList<ZNRecord>();
for (ZNRecord idealState : idealStateList)
{
String resourceName = idealState.getId();
HelixProperty property = accessor.getProperty(keyBuilder.currentState(host, sessionId, resourceName));
ZNRecord currentState =null;
if (property == null)
{
_logger.warn("Resource " + resourceName + " has null currentState");
currentState = new ZNRecord(resourceName);
}else{
currentState = property.getRecord();
}
currentStates.put(resourceName, currentState);
instanceCurrentStateList.add(currentState);
}
currentStatesMap.put(host, currentStates);
flatCurrentStateMap.put(host, ZNRecordRow.flatten(instanceCurrentStateList));
}
Query josqlQuery = new Query();
// Set the default bind variables
josqlQuery
.setVariable(
PropertyType.CONFIGS.toString() + "/" + ConfigScopeProperty.PARTICIPANT.toString(),
instanceConfigs);
josqlQuery.setVariable(PropertyType.IDEALSTATES.toString(), idealStatesMap);
josqlQuery.setVariable(PropertyType.LIVEINSTANCES.toString(), liveInstances);
josqlQuery.setVariable(PropertyType.STATEMODELDEFS.toString(), stateModelDefs);
josqlQuery.setVariable(PropertyType.EXTERNALVIEW.toString(), externalViewMap);
josqlQuery.setVariable(PropertyType.CURRENTSTATES.toString(), currentStatesMap);
josqlQuery.setVariable(PARTITIONS, partitions);
// Flat version of ZNRecords
josqlQuery.setVariable(
PropertyType.CONFIGS.toString() + "/" + ConfigScopeProperty.PARTICIPANT.toString()
+ FLATTABLE,
ZNRecordRow.flatten(instanceConfigs));
josqlQuery.setVariable(PropertyType.IDEALSTATES.toString() + FLATTABLE,
ZNRecordRow.flatten(idealStateList));
josqlQuery.setVariable(PropertyType.LIVEINSTANCES.toString() + FLATTABLE,
ZNRecordRow.flatten(liveInstances));
josqlQuery.setVariable(PropertyType.STATEMODELDEFS.toString() + FLATTABLE,
ZNRecordRow.flatten(stateModelDefs));
josqlQuery.setVariable(PropertyType.EXTERNALVIEW.toString() + FLATTABLE,
ZNRecordRow.flatten(externalViewList));
josqlQuery.setVariable(PropertyType.CURRENTSTATES.toString() + FLATTABLE,
flatCurrentStateMap.values());
josqlQuery.setVariable(PARTITIONS + FLATTABLE, ZNRecordRow.flatten(partitions));
// Set additional bind variables
if (bindVariables != null)
{
for (String key : bindVariables.keySet())
{
josqlQuery.setVariable(key, bindVariables.get(key));
}
}
josqlQuery.addFunctionHandler(new ZNRecordJosqlFunctionHandler());
josqlQuery.addFunctionHandler(new ZNRecordRow());
josqlQuery.addFunctionHandler(new Integer(0));
if (additionalFunctionHandlers != null)
{
for (Object functionHandler : additionalFunctionHandlers)
{
josqlQuery.addFunctionHandler(functionHandler);
}
}
return josqlQuery;
}
public List<Object> runJoSqlQuery(String josql, Map<String, Object> bindVariables,
List<Object> additionalFunctionHandlers) throws QueryParseException, QueryExecutionException
{
Query josqlQuery = prepareQuery(bindVariables, additionalFunctionHandlers);
// Per JoSql, select FROM <target> the target must be a object class that
// corresponds to a "table row",
// while the table (list of Objects) are put in the query by
// query.execute(List<Object>). In the input,
// In out case, the row is always a ZNRecord. But in SQL, the from target is
// a "table name".
String fromTargetString = parseFromTarget(josql);
List fromTargetList = null;
Object fromTarget = null;
if (fromTargetString.equalsIgnoreCase(PARTITIONS))
{
fromTarget = josqlQuery.getVariable(PARTITIONS.toString());
} else if (fromTargetString.equalsIgnoreCase(PropertyType.LIVEINSTANCES.toString()))
{
fromTarget = josqlQuery.getVariable(PropertyType.LIVEINSTANCES.toString());
} else if (fromTargetString.equalsIgnoreCase(PropertyType.CONFIGS.toString() + "/"
+ ConfigScopeProperty.PARTICIPANT.toString()))
{
fromTarget = josqlQuery.getVariable(PropertyType.CONFIGS.toString() + "/"
+ ConfigScopeProperty.PARTICIPANT.toString());
} else if (fromTargetString.equalsIgnoreCase(PropertyType.STATEMODELDEFS.toString()))
{
fromTarget = josqlQuery.getVariable(PropertyType.STATEMODELDEFS.toString());
} else if (fromTargetString.equalsIgnoreCase(PropertyType.EXTERNALVIEW.toString()))
{
fromTarget = josqlQuery.getVariable(PropertyType.EXTERNALVIEW.toString());
}
else if (fromTargetString.equalsIgnoreCase(PropertyType.IDEALSTATES.toString()))
{
fromTarget = josqlQuery.getVariable(PropertyType.IDEALSTATES.toString());
}
else if (fromTargetString.equalsIgnoreCase(PARTITIONS + FLATTABLE))
{
fromTarget = josqlQuery.getVariable(PARTITIONS.toString() + FLATTABLE);
} else if (fromTargetString.equalsIgnoreCase(PropertyType.LIVEINSTANCES.toString() + FLATTABLE))
{
fromTarget = josqlQuery.getVariable(PropertyType.LIVEINSTANCES.toString() + FLATTABLE);
} else if (fromTargetString.equalsIgnoreCase(PropertyType.CONFIGS.toString() + "/"
+ ConfigScopeProperty.PARTICIPANT.toString()
+ FLATTABLE))
{
fromTarget = josqlQuery.getVariable(PropertyType.CONFIGS.toString() + "/"
+ ConfigScopeProperty.PARTICIPANT.toString() + FLATTABLE);
} else if (fromTargetString
.equalsIgnoreCase(PropertyType.STATEMODELDEFS.toString() + FLATTABLE))
{
fromTarget = josqlQuery.getVariable(PropertyType.STATEMODELDEFS.toString() + FLATTABLE);
} else if (fromTargetString.equalsIgnoreCase(PropertyType.EXTERNALVIEW.toString() + FLATTABLE))
{
fromTarget = josqlQuery.getVariable(PropertyType.EXTERNALVIEW.toString() + FLATTABLE);
}
else if (fromTargetString.equalsIgnoreCase(PropertyType.IDEALSTATES.toString() + FLATTABLE))
{
fromTarget = josqlQuery.getVariable(PropertyType.IDEALSTATES.toString() + FLATTABLE);
}
else
{
throw new HelixException(
"Unknown query target "
+ fromTargetString
+ ". Target should be PARTITIONS, LIVEINSTANCES, CONFIGS, STATEMODELDEFS, IDEALSTATES, EXTERNALVIEW, and corresponding flat Tables");
}
fromTargetList = fromTargetString.endsWith(FLATTABLE) ? ((List<ZNRecordRow>) fromTarget)
: ((List<ZNRecord>) fromTarget);
// Per JoSql, select FROM <target> the target must be a object class that
// corresponds to a "table row"
// In out case, the row is always a ZNRecord
josql = josql.replaceFirst(
fromTargetString,
fromTargetString.endsWith(FLATTABLE) ? ZNRecordRow.class.getName() : ZNRecord.class
.getName());
josqlQuery.parse(josql);
QueryResults qr = josqlQuery.execute(fromTargetList);
return qr.getResults();
}
}