IdFieldMapper.java

/*
 * Licensed to ElasticSearch and Shay Banon under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. ElasticSearch 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.
 */

package org.elasticsearch.index.mapper.internal;

import com.google.common.collect.ImmutableList;
import com.google.common.collect.Iterables;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.document.Fieldable;
import org.apache.lucene.index.FieldInfo.IndexOptions;
import org.apache.lucene.search.*;
import org.elasticsearch.common.Nullable;
import org.elasticsearch.common.Strings;
import org.elasticsearch.common.lucene.Lucene;
import org.elasticsearch.common.lucene.search.XBooleanFilter;
import org.elasticsearch.common.xcontent.XContentBuilder;
import org.elasticsearch.common.xcontent.XContentParser;
import org.elasticsearch.index.mapper.*;
import org.elasticsearch.index.mapper.core.AbstractFieldMapper;
import org.elasticsearch.index.query.QueryParseContext;
import org.elasticsearch.index.search.UidFilter;

import java.io.IOException;
import java.util.Collection;
import java.util.Map;

import static org.elasticsearch.index.mapper.MapperBuilders.id;
import static org.elasticsearch.index.mapper.core.TypeParsers.parseField;

/**
 *
 */
public class IdFieldMapper extends AbstractFieldMapper<String> implements InternalMapper, RootMapper {

    public static final String NAME = "_id";

    public static final String CONTENT_TYPE = "_id";

    public static class Defaults extends AbstractFieldMapper.Defaults {
        public static final String NAME = IdFieldMapper.NAME;
        public static final String INDEX_NAME = IdFieldMapper.NAME;
        public static final Field.Index INDEX = Field.Index.NO;
        public static final Field.Store STORE = Field.Store.NO;
        public static final boolean OMIT_NORMS = true;
        public static final IndexOptions INDEX_OPTIONS = IndexOptions.DOCS_ONLY;
        public static final String PATH = null;
    }

    public static class Builder extends AbstractFieldMapper.Builder<Builder, IdFieldMapper> {

        private String path = Defaults.PATH;

        public Builder() {
            super(Defaults.NAME);
            indexName = Defaults.INDEX_NAME;
            store = Defaults.STORE;
            index = Defaults.INDEX;
            omitNorms = Defaults.OMIT_NORMS;
            indexOptions = Defaults.INDEX_OPTIONS;
        }

        public Builder path(String path) {
            this.path = path;
            return builder;
        }

        @Override
        public IdFieldMapper build(BuilderContext context) {
            return new IdFieldMapper(name, indexName, index, store, termVector, boost, omitNorms, indexOptions, path);
        }
    }

    public static class TypeParser implements Mapper.TypeParser {
        @Override
        public Mapper.Builder parse(String name, Map<String, Object> node, ParserContext parserContext) throws MapperParsingException {
            IdFieldMapper.Builder builder = id();
            parseField(builder, builder.name, node, parserContext);
            for (Map.Entry<String, Object> entry : node.entrySet()) {
                String fieldName = Strings.toUnderscoreCase(entry.getKey());
                Object fieldNode = entry.getValue();
                if (fieldName.equals("path")) {
                    builder.path(fieldNode.toString());
                }
            }
            return builder;
        }
    }

    private final String path;

    public IdFieldMapper() {
        this(Defaults.NAME, Defaults.INDEX_NAME, Defaults.INDEX);
    }

    public IdFieldMapper(Field.Index index) {
        this(Defaults.NAME, Defaults.INDEX_NAME, index);
    }

    protected IdFieldMapper(String name, String indexName, Field.Index index) {
        this(name, indexName, index, Defaults.STORE, Defaults.TERM_VECTOR, Defaults.BOOST,
                Defaults.OMIT_NORMS, Defaults.INDEX_OPTIONS, Defaults.PATH);
    }

    protected IdFieldMapper(String name, String indexName, Field.Index index, Field.Store store, Field.TermVector termVector,
                            float boost, boolean omitNorms, IndexOptions indexOptions, String path) {
        super(new Names(name, indexName, indexName, name), index, store, termVector, boost, omitNorms, indexOptions, Lucene.KEYWORD_ANALYZER,
                Lucene.KEYWORD_ANALYZER);
        this.path = path;
    }

    public String path() {
        return this.path;
    }

    public String value(Document document) {
        Fieldable field = document.getFieldable(names.indexName());
        return field == null ? null : value(field);
    }

    @Override
    public String value(Fieldable field) {
        return field.stringValue();
    }

    @Override
    public String valueFromString(String value) {
        return value;
    }

    @Override
    public String valueAsString(Fieldable field) {
        return value(field);
    }

    @Override
    public String indexedValue(String value) {
        return value;
    }

    @Override
    public boolean useFieldQueryWithQueryString() {
        return true;
    }

    @Override
    public Query fieldQuery(String value, @Nullable QueryParseContext context) {
        if (indexed() || context == null) {
            return super.fieldQuery(value, context);
        }
        UidFilter filter = new UidFilter(context.queryTypes(), ImmutableList.of(value), context.indexCache().bloomCache());
        // no need for constant score filter, since we don't cache the filter, and it always takes deletes into account
        return new ConstantScoreQuery(filter);
    }

    @Override
    public Filter fieldFilter(String value, @Nullable QueryParseContext context) {
        if (indexed() || context == null) {
            return super.fieldFilter(value, context);
        }
        return new UidFilter(context.queryTypes(), ImmutableList.of(value), context.indexCache().bloomCache());
    }

    @Override
    public Query prefixQuery(String value, @Nullable MultiTermQuery.RewriteMethod method, @Nullable QueryParseContext context) {
        if (indexed() || context == null) {
            return super.prefixQuery(value, method, context);
        }
        Collection<String> queryTypes = context.queryTypes();
        if (queryTypes.size() == 1) {
            PrefixQuery prefixQuery = new PrefixQuery(UidFieldMapper.TERM_FACTORY.createTerm(Uid.createUid(Iterables.getFirst(queryTypes, null), value)));
            if (method != null) {
                prefixQuery.setRewriteMethod(method);
            }
        }
        BooleanQuery query = new BooleanQuery();
        for (String queryType : queryTypes) {
            PrefixQuery prefixQuery = new PrefixQuery(UidFieldMapper.TERM_FACTORY.createTerm(Uid.createUid(queryType, value)));
            if (method != null) {
                prefixQuery.setRewriteMethod(method);
            }
            query.add(prefixQuery, BooleanClause.Occur.SHOULD);
        }
        return query;
    }

    @Override
    public Filter prefixFilter(String value, @Nullable QueryParseContext context) {
        if (indexed() || context == null) {
            return super.prefixFilter(value, context);
        }
        Collection<String> queryTypes = context.queryTypes();
        if (queryTypes.size() == 1) {
            return new PrefixFilter(UidFieldMapper.TERM_FACTORY.createTerm(Uid.createUid(Iterables.getFirst(queryTypes, null), value)));
        }
        XBooleanFilter filter = new XBooleanFilter();
        for (String queryType : queryTypes) {
            filter.addShould(new PrefixFilter(UidFieldMapper.TERM_FACTORY.createTerm(Uid.createUid(queryType, value))));
        }
        return filter;
    }

    @Override
    public void preParse(ParseContext context) throws IOException {
        if (context.sourceToParse().id() != null) {
            context.id(context.sourceToParse().id());
            super.parse(context);
        }
    }

    @Override
    public void postParse(ParseContext context) throws IOException {
        if (context.id() == null && !context.sourceToParse().flyweight()) {
            throw new MapperParsingException("No id found while parsing the content source");
        }
        // it either get built in the preParse phase, or get parsed...
    }

    @Override
    public void parse(ParseContext context) throws IOException {
        super.parse(context);
    }

    @Override
    public void validate(ParseContext context) throws MapperParsingException {
    }

    @Override
    public boolean includeInObject() {
        return true;
    }

    @Override
    protected Field parseCreateField(ParseContext context) throws IOException {
        XContentParser parser = context.parser();
        if (parser.currentName() != null && parser.currentName().equals(Defaults.NAME) && parser.currentToken().isValue()) {
            // we are in the parse Phase
            String id = parser.text();
            if (context.id() != null && !context.id().equals(id)) {
                throw new MapperParsingException("Provided id [" + context.id() + "] does not match the content one [" + id + "]");
            }
            context.id(id);
            if (index == Field.Index.NO && store == Field.Store.NO) {
                return null;
            }
            return new Field(names.indexName(), false, context.id(), store, index, termVector);
        } else {
            // we are in the pre/post parse phase
            if (index == Field.Index.NO && store == Field.Store.NO) {
                return null;
            }
            return new Field(names.indexName(), false, context.id(), store, index, termVector);
        }
    }

    @Override
    protected String contentType() {
        return CONTENT_TYPE;
    }

    @Override
    public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
        // if all are defaults, no sense to write it at all
        if (store == Defaults.STORE && index == Defaults.INDEX && path == Defaults.PATH) {
            return builder;
        }
        builder.startObject(CONTENT_TYPE);
        if (store != Defaults.STORE) {
            builder.field("store", store.name().toLowerCase());
        }
        if (index != Defaults.INDEX) {
            builder.field("index", index.name().toLowerCase());
        }
        if (path != Defaults.PATH) {
            builder.field("path", path);
        }
        builder.endObject();
        return builder;
    }

    @Override
    public void merge(Mapper mergeWith, MergeContext mergeContext) throws MergeMappingException {
        // do nothing here, no merging, but also no exception
    }
}