/*
* Copyright 2012 Paul Merlin.
*
* 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.
*/
package org.qi4j.index.elasticsearch;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
import org.elasticsearch.action.bulk.BulkRequestBuilder;
import org.elasticsearch.action.bulk.BulkResponse;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import org.qi4j.api.association.AssociationDescriptor;
import org.qi4j.api.entity.EntityDescriptor;
import org.qi4j.api.entity.EntityReference;
import org.qi4j.api.injection.scope.Service;
import org.qi4j.api.injection.scope.Structure;
import org.qi4j.api.injection.scope.This;
import org.qi4j.api.mixin.Mixins;
import org.qi4j.api.property.PropertyDescriptor;
import org.qi4j.api.service.qualifier.Tagged;
import org.qi4j.api.structure.Module;
import org.qi4j.api.type.ValueType;
import org.qi4j.api.usecase.UsecaseBuilder;
import org.qi4j.api.util.Classes;
import org.qi4j.api.value.ValueSerialization;
import org.qi4j.api.value.ValueSerializer;
import org.qi4j.functional.Iterables;
import org.qi4j.spi.entity.EntityState;
import org.qi4j.spi.entity.EntityStatus;
import org.qi4j.spi.entity.ManyAssociationState;
import org.qi4j.spi.entitystore.EntityStore;
import org.qi4j.spi.entitystore.EntityStoreUnitOfWork;
import org.qi4j.spi.entitystore.StateChangeListener;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Listen to Entity state changes and index them in ElasticSearch.
*
* QUID Use two indices, one for strict queries, one for full text and fuzzy search?
*/
@Mixins( ElasticSearchIndexer.Mixin.class )
public interface ElasticSearchIndexer
extends StateChangeListener
{
class Mixin
implements StateChangeListener
{
private static final Logger LOGGER = LoggerFactory.getLogger( ElasticSearchIndexer.class );
@Structure
private Module module;
@Service
private EntityStore entityStore;
@Service
@Tagged( ValueSerialization.Formats.JSON )
private ValueSerializer valueSerializer;
@This
private ElasticSearchSupport support;
public void emptyIndex()
{
support.client().admin().indices().prepareDelete( support.index() ).execute().actionGet();
}
@Override
public void notifyChanges( Iterable<EntityState> changedStates )
{
// All updated or new states
Map<String, EntityState> newStates = new HashMap<String, EntityState>();
for( EntityState eState : changedStates )
{
if( eState.status() == EntityStatus.UPDATED || eState.status() == EntityStatus.NEW )
{
newStates.put( eState.identity().identity(), eState );
}
}
EntityStoreUnitOfWork uow = entityStore.newUnitOfWork( UsecaseBuilder.newUsecase( "Load associations for indexing" ),
module,
System.currentTimeMillis() );
// Bulk index request builder
BulkRequestBuilder bulkBuilder = support.client().prepareBulk();
// Handle changed entity states
for( EntityState changedState : changedStates )
{
if( changedState.entityDescriptor().queryable() )
{
switch( changedState.status() )
{
case REMOVED:
LOGGER.trace( "Removing Entity State from Index: {}", changedState );
remove( bulkBuilder, changedState.identity().identity() );
break;
case UPDATED:
LOGGER.trace( "Updating Entity State in Index: {}", changedState );
remove( bulkBuilder, changedState.identity().identity() );
String updatedJson = toJSON( changedState, newStates, uow );
LOGGER.trace( "Will index: {}", updatedJson );
index( bulkBuilder, changedState.identity().identity(), updatedJson );
break;
case NEW:
LOGGER.trace( "Creating Entity State in Index: {}", changedState );
String newJson = toJSON( changedState, newStates, uow );
LOGGER.trace( "Will index: {}", newJson );
index( bulkBuilder, changedState.identity().identity(), newJson );
break;
case LOADED:
default:
// Ignored
break;
}
}
}
uow.discard();
if( bulkBuilder.numberOfActions() > 0 )
{
// Execute bulk actions
BulkResponse bulkResponse = bulkBuilder.execute().actionGet();
// Handle errors
if( bulkResponse.hasFailures() )
{
throw new ElasticSearchIndexException( bulkResponse.buildFailureMessage() );
}
LOGGER.debug( "Indexing changed Entity states took {}ms", bulkResponse.tookInMillis() );
// Refresh index
support.client().admin().indices().prepareRefresh( support.index() ).execute().actionGet();
}
}
private void remove( BulkRequestBuilder bulkBuilder, String identity )
{
bulkBuilder.add( support.client().
prepareDelete( support.index(), support.entitiesType(), identity ) );
}
private void index( BulkRequestBuilder bulkBuilder, String identity, String json )
{
bulkBuilder.add( support.client().
prepareIndex( support.index(), support.entitiesType(), identity ).
setSource( json ) );
}
/**
* <pre>
* {
* "_identity": "ENTITY-IDENTITY",
* "_types": [ "All", "Entity", "types" ],
* "property.name": property.value,
* "association.name": "ASSOCIATED-IDENTITY",
* "manyassociation.name": [ "ASSOCIATED", "IDENTITIES" ]
* }
* </pre>
*/
private String toJSON( EntityState state, Map<String, EntityState> newStates, EntityStoreUnitOfWork uow )
{
try
{
JSONObject json = new JSONObject();
json.put( "_identity", state.identity().identity() );
json.put( "_types", Iterables.toList( Iterables.map( Classes.toClassName(), state.entityDescriptor().mixinTypes() ) ) );
EntityDescriptor entityType = state.entityDescriptor();
// Properties
for( PropertyDescriptor propDesc : entityType.state().properties() )
{
if( propDesc.queryable() )
{
String key = propDesc.qualifiedName().name();
Object value = state.propertyValueOf( propDesc.qualifiedName() );
if( value == null || ValueType.isPrimitiveValue( value ) )
{
json.put( key, value );
}
else
{
// TODO Theses tests are pretty fragile, find a better way to fix this, Jackson API should behave better
String serialized = valueSerializer.serialize( value );
if( serialized.startsWith( "{" ) )
{
json.put( key, new JSONObject( serialized ) );
}
else if( serialized.startsWith( "[" ) )
{
json.put( key, new JSONArray( serialized ) );
}
else
{
json.put( key, serialized );
}
}
}
}
// Associations
for( AssociationDescriptor assocDesc : entityType.state().associations() )
{
if( assocDesc.queryable() )
{
String key = assocDesc.qualifiedName().name();
EntityReference associated = state.associationValueOf( assocDesc.qualifiedName() );
Object value;
if( associated == null )
{
value = null;
}
else
{
if( assocDesc.isAggregated() || support.indexNonAggregatedAssociations() )
{
if( newStates.containsKey( associated.identity() ) )
{
value = new JSONObject( toJSON( newStates.get( associated.identity() ), newStates, uow ) );
}
else
{
EntityState assocState = uow.entityStateOf( EntityReference.parseEntityReference( associated.identity() ) );
value = new JSONObject( toJSON( assocState, newStates, uow ) );
}
}
else
{
value = new JSONObject( Collections.singletonMap( "identity", associated.identity() ) );
}
}
json.put( key, value );
}
}
// ManyAssociations
for( AssociationDescriptor manyAssocDesc : entityType.state().manyAssociations() )
{
if( manyAssocDesc.queryable() )
{
String key = manyAssocDesc.qualifiedName().name();
JSONArray array = new JSONArray();
ManyAssociationState associateds = state.manyAssociationValueOf( manyAssocDesc.qualifiedName() );
for( EntityReference associated : associateds )
{
if( manyAssocDesc.isAggregated() || support.indexNonAggregatedAssociations() )
{
if( newStates.containsKey( associated.identity() ) )
{
array.put( new JSONObject( toJSON( newStates.get( associated.identity() ), newStates, uow ) ) );
}
else
{
EntityState assocState = uow.entityStateOf( EntityReference.parseEntityReference( associated.identity() ) );
array.put( new JSONObject( toJSON( assocState, newStates, uow ) ) );
}
}
else
{
array.put( new JSONObject( Collections.singletonMap( "identity", associated.identity() ) ) );
}
}
json.put( key, array );
}
}
return json.toString();
}
catch( JSONException e )
{
throw new ElasticSearchIndexException( "Could not index EntityState", e );
}
}
}
}