Hibernate Search：为自定义 FieldBridge 配置 Facet

Question

在这个例子中DateSplitBridge.java动态字段被添加到索引文档中：

public class DateSplitBridge implements FieldBridge {
...
   public void set(String name, Object value, Document document, LuceneOptions luceneOptions) {
...
      luceneOptions.addFieldToDocument( name + ".year", String.valueOf( year ), document);
...

如何为此类临时字段配置 Facet？ 是否可以在 FieldBridge 本身中完成？

Answer 1

在https://hibernate.atlassian.net/browse/HSEARCH-1686?page=com.atlassian.jira.plugin.system.issuetabpanels%3Acomment-tabpanel&showAll=true找到解决方案

这里采用的版本：companyId是实体成员（Long），isFavorite也是成员（布尔）。结果：在索引文档中有类似的字段：customFieldFacet_1234，其值为：“true”或“false”。注意：没有@Facet注解

用法：

@Field(analyze = Analyze.NO, store = Store.YES, bridge = @FieldBridge(impl = CustomFieldBridge.class))
@Transient
public CustomField getFacetingCustomField() {
    return new CustomField("customFieldFacet_" + companyId, isFavorite);
}

场桥：

import org.apache.lucene.document.Document;
import org.apache.lucene.facet.sortedset.SortedSetDocValuesFacetField;
import org.hibernate.search.bridge.FieldBridge;
import org.hibernate.search.bridge.LuceneOptions;

import java.io.IOException;

public class CustomFieldBridge implements FieldBridge {

    public void set(String name, Object value, Document document, LuceneOptions luceneOptions) {
        if (value != null) {
            CustomField customField = (CustomField) value;
            if (customField.getFieldValue() != null) {
                String fieldName = customField.getFieldName();
                String fieldValue = customField.getFieldValue();
                CustomFacetsConfig config = new CustomFacetsConfig();
                config.setIndexFieldName(fieldName, fieldName);
                Document doc = new Document();
                doc.add(new SortedSetDocValuesFacetField(fieldName, fieldValue));
                try {
                    config.CustomBuild(doc, document);
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }
}

CustomFacetConfig：

import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.document.SortedSetDocValuesField;
import org.apache.lucene.document.StringField;
import org.apache.lucene.facet.FacetsConfig;
import org.apache.lucene.facet.sortedset.SortedSetDocValuesFacetField;
import org.apache.lucene.facet.taxonomy.FacetLabel;
import org.apache.lucene.index.IndexableField;
import org.apache.lucene.util.BytesRef;

import java.io.IOException;
import java.util.*;

public class CustomFacetsConfig extends FacetsConfig {

    public Document CustomBuild(Document doc, Document destDocument) throws IOException {
        Map<String, List<SortedSetDocValuesFacetField>> dvByField = new HashMap<>();
        Set<String> seenDims = new HashSet<>();
        for (IndexableField field : doc.getFields()) {
            if (field.fieldType() == SortedSetDocValuesFacetField.TYPE) {
                SortedSetDocValuesFacetField facetField = (SortedSetDocValuesFacetField) field;
                FacetsConfig.DimConfig dimConfig = getDimConfig(facetField.dim);
                if (dimConfig.multiValued == false) {
                    checkSeen(seenDims, facetField.dim);
                }
                String indexFieldName = dimConfig.indexFieldName;
                List<SortedSetDocValuesFacetField> fields = dvByField.get(indexFieldName);
                if (fields == null) {
                    fields = new ArrayList<>();
                    dvByField.put(indexFieldName, fields);
                }
                fields.add(facetField);
            }
        }
        processSSDVFacetFields(dvByField, destDocument);
        return destDocument;
    }

    private void checkSeen(Set<String> seenDims, String dim) {
        if (seenDims.contains(dim)) {
            throw new IllegalArgumentException("dimension " + dim + " is not multiValued, but it appears more than once in this document");
        }
        seenDims.add(dim);
    }

    private void processSSDVFacetFields(Map<String, List<SortedSetDocValuesFacetField>> byField, Document doc) throws IOException {
        for (Map.Entry<String, List<SortedSetDocValuesFacetField>> ent : byField.entrySet()) {
            String indexFieldName = ent.getKey();
            for (SortedSetDocValuesFacetField facetField : ent.getValue()) {
                FacetLabel cp = new FacetLabel(facetField.dim, facetField.label);
                String fullPath = pathToString(cp.components, cp.length);
                doc.add(new SortedSetDocValuesField(indexFieldName, new BytesRef(fullPath)));
                doc.add(new StringField(indexFieldName, fullPath, Field.Store.YES));
            }
        }
    }

}