當(dāng)需要將term的權(quán)重存儲(chǔ)到索引中時(shí)乘综，需要保存成payload的格式：
源代碼：https://github.com/limingnihao/elasticsearch-reference/tree/master/Examples
官方文檔：https://www.elastic.co/guide/en/elasticsearch/reference/7.10/analysis-delimited-payload-tokenfilter.html
類似于：
the|0 brown|3 fox|4 is|0 quick|10
查詢的時(shí)候，如果需要用到保存好的value卡辰，則需要lucene 的PayloadScoreQuery或者PayloadCheckQuery。
PayloadScoreQuery：
首先查看下lucene的PayloadScoreQuery的構(gòu)造方法：
/**
* Creates a new PayloadScoreQuery
* @param wrappedQuery the query to wrap
* @param function a PayloadFunction to use to modify the scores
* @param decoder a PayloadDecoder to convert payloads into float values
* @param includeSpanScore include both span score and payload score in the scoring algorithm
*/
public PayloadScoreQuery(SpanQuery wrappedQuery, PayloadFunction function, PayloadDecoder decoder, boolean includeSpanScore) {
this.wrappedQuery = Objects.requireNonNull(wrappedQuery);
this.function = Objects.requireNonNull(function);
this.decoder = Objects.requireNonNull(decoder);
this.includeSpanScore = includeSpanScore;
}
可以發(fā)現(xiàn)九妈，需要構(gòu)造4個(gè)參數(shù)：
- SpanQuery wrappedQuery。進(jìn)行召回的query萌朱，必須是spanQuery
- PayloadFunction function。當(dāng)命中多個(gè)term時(shí)嚷兔，得分的計(jì)算規(guī)則，max冒晰、min同衣、sum壶运、
- PayloadDecoder decoder。保存的value的解碼方式蒋情。int或float類型
- boolean includeSpanScore。是否使用保存的分?jǐn)?shù)棵癣。
下面開(kāi)始開(kāi)發(fā)，需要構(gòu)建2個(gè)類一個(gè)是plugin狈谊、一個(gè)是builder
PayloadScoreQParserPlugin
用于構(gòu)造Builder的
public class PayloadScoreQParserPlugin extends Plugin implements SearchPlugin {
@Override
public List<QuerySpec<?>> getQueries() {
return Collections.singletonList(
new QuerySpec<>(PayloadScoreQueryBuilder.NAME, PayloadScoreQueryBuilder::new, PayloadScoreQueryBuilder::fromXContent)
);
}
}
PayloadScoreQueryBuilder
首先解析參數(shù)的fromXContent方法：
主要用于解析我們自定義的參數(shù)：query、func河劝、calc(后續(xù)擴(kuò)展權(quán)重交叉計(jì)算)壁榕、includeSpanScore
public static QueryBuilder fromXContent(XContentParser parser) throws IOException {
String currentFieldName = null;
XContentParser.Token token;
QueryBuilder iqb = null;
String func = null;
String calc = null;
boolean includeSpanScore = false;
while ((token = parser.nextToken()) != XContentParser.Token.END_OBJECT) {
if (token == XContentParser.Token.FIELD_NAME) {
currentFieldName = parser.currentName();
} else if (token == XContentParser.Token.START_OBJECT) {
if (QUERY_FIELD.match(currentFieldName, parser.getDeprecationHandler())) {
iqb = parseInnerQueryBuilder(parser);
} else {
throw new ParsingException(parser.getTokenLocation(),
"[" + NAME + "] query does not support [" + currentFieldName + "]");
}
} else if (token.isValue()) {
if (FUNC_FIELD.match(currentFieldName, parser.getDeprecationHandler())) {
func = parser.text();
} else if (CALC_FIELD.match(currentFieldName, parser.getDeprecationHandler())) {
calc = parser.text();
} else if (INCLUDE_SPAN_SCORE_FIELD.match(currentFieldName, parser.getDeprecationHandler())) {
includeSpanScore = parser.booleanValue();
} else {
throw new ParsingException(parser.getTokenLocation(),
"[" + NAME + "] query does not support [" + currentFieldName + "]");
}
}
}
return new PayloadScoreQueryBuilder(iqb, func, calc, includeSpanScore);
}
構(gòu)造PayloadScoreQuery的doToQuery方法：
主要是將lucene的PayloadScoreQuery類需要的4個(gè)參數(shù)構(gòu)造出來(lái)：
protected Query doToQuery(SearchExecutionContext context) throws IOException {
// query parse
SpanQuery spanQuery = null;
try {
spanQuery = (SpanQuery) query.toQuery(context);
} catch (IOException e) {
throw new IllegalArgumentException(e);
}
if (spanQuery == null) {
throw new IllegalArgumentException("SpanQuery is null");
}
PayloadFunction payloadFunction = PayloadUtils.getPayloadFunction(this.func);
if (payloadFunction == null) {
throw new IllegalArgumentException("Unknown payload function: " + func);
}
PayloadDecoder payloadDecoder = PayloadUtils.getPayloadDecoder("float");
return new PayloadScoreQuery(spanQuery, payloadFunction, payloadDecoder, this.includeSpanScore);
}
PayloadScoreQueryBuilder完整代碼
package org.elasticsearch.plugins.payload;
import org.apache.lucene.queries.payloads.PayloadDecoder;
import org.apache.lucene.queries.payloads.PayloadFunction;
import org.apache.lucene.queries.payloads.PayloadScoreQuery;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.spans.SpanQuery;
import org.elasticsearch.common.ParseField;
import org.elasticsearch.common.ParsingException;
import org.elasticsearch.common.io.stream.StreamInput;
import org.elasticsearch.common.io.stream.StreamOutput;
import org.elasticsearch.common.xcontent.XContentBuilder;
import org.elasticsearch.common.xcontent.XContentParser;
import org.elasticsearch.index.query.*;
import java.io.IOException;
import java.util.Objects;
public class PayloadScoreQueryBuilder extends AbstractQueryBuilder<PayloadScoreQueryBuilder> {
public static final String NAME = "payload_score";
private static final ParseField QUERY_FIELD = new ParseField("query");
private static final ParseField FUNC_FIELD = new ParseField("func");
private static final ParseField CALC_FIELD = new ParseField("calc");
private static final ParseField INCLUDE_SPAN_SCORE_FIELD = new ParseField("includeSpanScore");
private final QueryBuilder query;
private final String func;
private final String calc;
private final boolean includeSpanScore;
public PayloadScoreQueryBuilder(QueryBuilder query, String func, String calc, boolean includeSpanScore) {
this.query = requireValue(query, "[" + NAME + "] requires '" + QUERY_FIELD.getPreferredName() + "' field");
this.func = func;
this.calc = calc;
this.includeSpanScore = includeSpanScore;
}
public PayloadScoreQueryBuilder(StreamInput in) throws IOException {
super(in);
this.query = in.readNamedWriteable(QueryBuilder.class);
this.func = in.readString();
this.calc = in.readString();
this.includeSpanScore = in.readBoolean();
}
@Override
protected void doWriteTo(StreamOutput out) throws IOException {
out.writeNamedWriteable(query);
out.writeString(this.func);
out.writeString(this.calc);
out.writeBoolean(this.includeSpanScore);
}
@Override
protected void doXContent(XContentBuilder builder, Params params) throws IOException {
builder.startObject(NAME);
builder.field(QUERY_FIELD.getPreferredName());
query.toXContent(builder, params);
builder.field(FUNC_FIELD.getPreferredName(), this.func);
builder.field(CALC_FIELD.getPreferredName(), this.calc);
builder.field(INCLUDE_SPAN_SCORE_FIELD.getPreferredName(), this.includeSpanScore);
printBoostAndQueryName(builder);
builder.endObject();
}
public static QueryBuilder fromXContent(XContentParser parser) throws IOException {
String currentFieldName = null;
XContentParser.Token token;
QueryBuilder iqb = null;
String func = null;
String calc = null;
boolean includeSpanScore = false;
while ((token = parser.nextToken()) != XContentParser.Token.END_OBJECT) {
if (token == XContentParser.Token.FIELD_NAME) {
currentFieldName = parser.currentName();
} else if (token == XContentParser.Token.START_OBJECT) {
if (QUERY_FIELD.match(currentFieldName, parser.getDeprecationHandler())) {
iqb = parseInnerQueryBuilder(parser);
} else {
throw new ParsingException(parser.getTokenLocation(),
"[" + NAME + "] query does not support [" + currentFieldName + "]");
}
} else if (token.isValue()) {
if (FUNC_FIELD.match(currentFieldName, parser.getDeprecationHandler())) {
func = parser.text();
} else if (CALC_FIELD.match(currentFieldName, parser.getDeprecationHandler())) {
calc = parser.text();
} else if (INCLUDE_SPAN_SCORE_FIELD.match(currentFieldName, parser.getDeprecationHandler())) {
includeSpanScore = parser.booleanValue();
} else {
throw new ParsingException(parser.getTokenLocation(),
"[" + NAME + "] query does not support [" + currentFieldName + "]");
}
}
}
return new PayloadScoreQueryBuilder(iqb, func, calc, includeSpanScore);
}
@Override
protected Query doToQuery(SearchExecutionContext context) throws IOException {
// query parse
SpanQuery spanQuery = null;
try {
spanQuery = (SpanQuery) query.toQuery(context);
} catch (IOException e) {
throw new IllegalArgumentException(e);
}
if (spanQuery == null) {
throw new IllegalArgumentException("SpanQuery is null");
}
PayloadFunction payloadFunction = PayloadUtils.getPayloadFunction(this.func);
if (payloadFunction == null) {
throw new IllegalArgumentException("Unknown payload function: " + func);
}
PayloadDecoder payloadDecoder = PayloadUtils.getPayloadDecoder("float");
return new PayloadScoreQuery(spanQuery, payloadFunction, payloadDecoder, this.includeSpanScore);
}
@Override
protected boolean doEquals(PayloadScoreQueryBuilder that) {
return Objects.equals(query, that.query)
&& Objects.equals(func, that.func)
&& Objects.equals(calc, that.calc)
&& Objects.equals(includeSpanScore, that.includeSpanScore);
}
@Override
protected int doHashCode() {
return Objects.hash(query, func, calc, includeSpanScore);
}
@Override
public String getWriteableName() {
return NAME;
}
}
執(zhí)行示例：
POST http://127.0.0.1:9200/position/_search
{
"query": {
"payload_score": {
"func": "sum",
"calc": "sum",
"includeSpanScore": "false",
"query": {
"span_or": {
"clauses": [
{
"span_term": {
"FIELD": "test"
}
}
]
}
}
}
}
}
