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* Licensed to Elasticsearch 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.search.suggest.completion;
import org.elasticsearch.ElasticsearchParseException;
import org.elasticsearch.common.ParseField;
import org.elasticsearch.common.bytes.BytesReference;
import org.elasticsearch.common.io.stream.StreamInput;
import org.elasticsearch.common.io.stream.StreamOutput;
import org.elasticsearch.common.unit.Fuzziness;
import org.elasticsearch.common.xcontent.ObjectParser;
import org.elasticsearch.common.xcontent.ToXContent;
import org.elasticsearch.common.xcontent.XContentBuilder;
import org.elasticsearch.common.xcontent.XContentFactory;
import org.elasticsearch.common.xcontent.XContentParser;
import org.elasticsearch.common.xcontent.XContentType;
import org.elasticsearch.index.mapper.CompletionFieldMapper;
import org.elasticsearch.index.mapper.MappedFieldType;
import org.elasticsearch.index.mapper.MapperService;
import org.elasticsearch.index.query.QueryShardContext;
import org.elasticsearch.search.suggest.SuggestionBuilder;
import org.elasticsearch.search.suggest.SuggestionSearchContext.SuggestionContext;
import org.elasticsearch.search.suggest.completion.context.ContextMapping;
import org.elasticsearch.search.suggest.completion.context.ContextMappings;
import java.io.IOException;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Objects;
/**
* Defines a suggest command based on a prefix, typically to provide "auto-complete" functionality
* for users as they type search terms. The implementation of the completion service uses FSTs that
* are created at index-time and so must be defined in the mapping with the type "completion" before
* indexing.
*/
public class CompletionSuggestionBuilder extends SuggestionBuilder<CompletionSuggestionBuilder> {
static final String SUGGESTION_NAME = "completion";
static final ParseField CONTEXTS_FIELD = new ParseField("contexts", "context");
/**
* {
* "field" : STRING
* "size" : INT
* "fuzzy" : BOOLEAN | FUZZY_OBJECT
* "contexts" : QUERY_CONTEXTS
* "regex" : REGEX_OBJECT
* "payload" : STRING_ARRAY
* }
*/
private static final ObjectParser<CompletionSuggestionBuilder.InnerBuilder, Void> PARSER = new ObjectParser<>(SUGGESTION_NAME, null);
static {
PARSER.declareField((parser, completionSuggestionContext, context) -> {
if (parser.currentToken() == XContentParser.Token.VALUE_BOOLEAN) {
if (parser.booleanValue()) {
completionSuggestionContext.fuzzyOptions = new FuzzyOptions.Builder().build();
}
} else {
completionSuggestionContext.fuzzyOptions = FuzzyOptions.parse(parser);
}
},
FuzzyOptions.FUZZY_OPTIONS, ObjectParser.ValueType.OBJECT_OR_BOOLEAN);
PARSER.declareField((parser, completionSuggestionContext, context) ->
completionSuggestionContext.regexOptions = RegexOptions.parse(parser),
RegexOptions.REGEX_OPTIONS, ObjectParser.ValueType.OBJECT);
PARSER.declareString(CompletionSuggestionBuilder.InnerBuilder::field, FIELDNAME_FIELD);
PARSER.declareString(CompletionSuggestionBuilder.InnerBuilder::analyzer, ANALYZER_FIELD);
PARSER.declareInt(CompletionSuggestionBuilder.InnerBuilder::size, SIZE_FIELD);
PARSER.declareInt(CompletionSuggestionBuilder.InnerBuilder::shardSize, SHARDSIZE_FIELD);
PARSER.declareField((p, v, c) -> {
// Copy the current structure. We will parse, once the mapping is provided
XContentBuilder builder = XContentFactory.contentBuilder(XContentType.JSON);
builder.copyCurrentStructure(p);
v.contextBytes = builder.bytes();
p.skipChildren();
}, CONTEXTS_FIELD, ObjectParser.ValueType.OBJECT); // context is deprecated
}
protected FuzzyOptions fuzzyOptions;
protected RegexOptions regexOptions;
protected BytesReference contextBytes = null;
public CompletionSuggestionBuilder(String field) {
super(field);
}
/**
* internal copy constructor that copies over all class fields except for the field which is
* set to the one provided in the first argument
*/
private CompletionSuggestionBuilder(String fieldname, CompletionSuggestionBuilder in) {
super(fieldname, in);
fuzzyOptions = in.fuzzyOptions;
regexOptions = in.regexOptions;
contextBytes = in.contextBytes;
}
/**
* Read from a stream.
*/
public CompletionSuggestionBuilder(StreamInput in) throws IOException {
super(in);
fuzzyOptions = in.readOptionalWriteable(FuzzyOptions::new);
regexOptions = in.readOptionalWriteable(RegexOptions::new);
contextBytes = in.readOptionalBytesReference();
}
@Override
public void doWriteTo(StreamOutput out) throws IOException {
out.writeOptionalWriteable(fuzzyOptions);
out.writeOptionalWriteable(regexOptions);
out.writeOptionalBytesReference(contextBytes);
}
/**
* Sets the prefix to provide completions for.
* The prefix gets analyzed by the suggest analyzer.
*/
@Override
public CompletionSuggestionBuilder prefix(String prefix) {
super.prefix(prefix);
return this;
}
/**
* Same as {@link #prefix(String)} with fuzziness of <code>fuzziness</code>
*/
public CompletionSuggestionBuilder prefix(String prefix, Fuzziness fuzziness) {
super.prefix(prefix);
this.fuzzyOptions = new FuzzyOptions.Builder().setFuzziness(fuzziness).build();
return this;
}
/**
* Same as {@link #prefix(String)} with full fuzzy options
* see {@link FuzzyOptions.Builder}
*/
public CompletionSuggestionBuilder prefix(String prefix, FuzzyOptions fuzzyOptions) {
super.prefix(prefix);
this.fuzzyOptions = fuzzyOptions;
return this;
}
/**
* Sets a regular expression pattern for prefixes to provide completions for.
*/
@Override
public CompletionSuggestionBuilder regex(String regex) {
super.regex(regex);
return this;
}
/**
* Same as {@link #regex(String)} with full regular expression options
* see {@link RegexOptions.Builder}
*/
public CompletionSuggestionBuilder regex(String regex, RegexOptions regexOptions) {
this.regex(regex);
this.regexOptions = regexOptions;
return this;
}
/**
* Sets query contexts for completion
* @param queryContexts named query contexts
* see {@link org.elasticsearch.search.suggest.completion.context.CategoryQueryContext}
* and {@link org.elasticsearch.search.suggest.completion.context.GeoQueryContext}
*/
public CompletionSuggestionBuilder contexts(Map<String, List<? extends ToXContent>> queryContexts) {
Objects.requireNonNull(queryContexts, "contexts must not be null");
try {
XContentBuilder contentBuilder = XContentFactory.jsonBuilder();
contentBuilder.startObject();
for (Map.Entry<String, List<? extends ToXContent>> contextEntry : queryContexts.entrySet()) {
contentBuilder.startArray(contextEntry.getKey());
for (ToXContent queryContext : contextEntry.getValue()) {
queryContext.toXContent(contentBuilder, EMPTY_PARAMS);
}
contentBuilder.endArray();
}
contentBuilder.endObject();
return contexts(contentBuilder);
} catch (IOException e) {
throw new IllegalArgumentException(e);
}
}
private CompletionSuggestionBuilder contexts(XContentBuilder contextBuilder) {
contextBytes = contextBuilder.bytes();
return this;
}
private static class InnerBuilder extends CompletionSuggestionBuilder {
private String field;
InnerBuilder() {
super("_na_");
}
private InnerBuilder field(String field) {
this.field = field;
return this;
}
}
@Override
protected XContentBuilder innerToXContent(XContentBuilder builder, Params params) throws IOException {
if (fuzzyOptions != null) {
fuzzyOptions.toXContent(builder, params);
}
if (regexOptions != null) {
regexOptions.toXContent(builder, params);
}
if (contextBytes != null) {
builder.rawField(CONTEXTS_FIELD.getPreferredName(), contextBytes);
}
return builder;
}
public static CompletionSuggestionBuilder fromXContent(XContentParser parser) throws IOException {
CompletionSuggestionBuilder.InnerBuilder builder = new CompletionSuggestionBuilder.InnerBuilder();
PARSER.parse(parser, builder, null);
String field = builder.field;
// now we should have field name, check and copy fields over to the suggestion builder we return
if (field == null) {
throw new ElasticsearchParseException(
"the required field option [" + FIELDNAME_FIELD.getPreferredName() + "] is missing");
}
return new CompletionSuggestionBuilder(field, builder);
}
@Override
public SuggestionContext build(QueryShardContext context) throws IOException {
CompletionSuggestionContext suggestionContext = new CompletionSuggestionContext(context);
// copy over common settings to each suggestion builder
final MapperService mapperService = context.getMapperService();
populateCommonFields(mapperService, suggestionContext);
suggestionContext.setFuzzyOptions(fuzzyOptions);
suggestionContext.setRegexOptions(regexOptions);
MappedFieldType mappedFieldType = mapperService.fullName(suggestionContext.getField());
if (mappedFieldType == null ||
mappedFieldType instanceof CompletionFieldMapper.CompletionFieldType == false) {
throw new IllegalArgumentException("Field [" + suggestionContext.getField() + "] is not a completion suggest field");
}
if (mappedFieldType instanceof CompletionFieldMapper.CompletionFieldType) {
CompletionFieldMapper.CompletionFieldType type = (CompletionFieldMapper.CompletionFieldType) mappedFieldType;
suggestionContext.setFieldType(type);
if (type.hasContextMappings() && contextBytes != null) {
try (XContentParser contextParser = XContentFactory.xContent(contextBytes).createParser(context.getXContentRegistry(),
contextBytes)) {
if (type.hasContextMappings() && contextParser != null) {
ContextMappings contextMappings = type.getContextMappings();
contextParser.nextToken();
Map<String, List<ContextMapping.InternalQueryContext>> queryContexts = new HashMap<>(contextMappings.size());
assert contextParser.currentToken() == XContentParser.Token.START_OBJECT;
XContentParser.Token currentToken;
String currentFieldName;
while ((currentToken = contextParser.nextToken()) != XContentParser.Token.END_OBJECT) {
if (currentToken == XContentParser.Token.FIELD_NAME) {
currentFieldName = contextParser.currentName();
final ContextMapping mapping = contextMappings.get(currentFieldName);
queryContexts.put(currentFieldName, mapping.parseQueryContext(context.newParseContext(contextParser)));
}
}
suggestionContext.setQueryContexts(queryContexts);
}
}
} else if (contextBytes != null) {
throw new IllegalArgumentException("suggester [" + type.name() + "] doesn't expect any context");
}
}
assert suggestionContext.getFieldType() != null : "no completion field type set";
return suggestionContext;
}
@Override
public String getWriteableName() {
return SUGGESTION_NAME;
}
@Override
protected boolean doEquals(CompletionSuggestionBuilder other) {
return Objects.equals(fuzzyOptions, other.fuzzyOptions) &&
Objects.equals(regexOptions, other.regexOptions) &&
Objects.equals(contextBytes, other.contextBytes);
}
@Override
protected int doHashCode() {
return Objects.hash(fuzzyOptions, regexOptions, contextBytes);
}
}