Spring Boot集成Elasticsearch自定义序列化

作者: 阿拉喵_d271 | 来源:发表于2018-10-18 18:29 被阅读0次

spring-boot-elasticsearch对搜索结果反序列化时不能获取_score值，业务中又必须用所以就改一下框架里的序列化代码

继承AbstractResultMapper增加读取/写入_score的代码，我是使用@Score在实体里标记写到哪个字段实现的


import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

/**
 * @author weizhiwen
 * @date 2018/7/4
 */
@Retention(RetentionPolicy.RUNTIME)
@Target({ElementType.FIELD, ElementType.METHOD, ElementType.ANNOTATION_TYPE})
public @interface Score {

}


import com.fasterxml.jackson.core.JsonEncoding;
import com.fasterxml.jackson.core.JsonFactory;
import com.fasterxml.jackson.core.JsonGenerator;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang.StringUtils;
import org.apache.commons.text.WordUtils;
import org.elasticsearch.action.get.GetResponse;
import org.elasticsearch.action.get.MultiGetItemResponse;
import org.elasticsearch.action.get.MultiGetResponse;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHitField;
import org.springframework.data.domain.Pageable;
import org.springframework.data.elasticsearch.ElasticsearchException;
import org.springframework.data.elasticsearch.annotations.Document;
import org.springframework.data.elasticsearch.annotations.ScriptedField;
import org.springframework.data.elasticsearch.core.AbstractResultMapper;
import org.springframework.data.elasticsearch.core.DefaultEntityMapper;
import org.springframework.data.elasticsearch.core.EntityMapper;
import org.springframework.data.elasticsearch.core.aggregation.AggregatedPage;
import org.springframework.data.elasticsearch.core.aggregation.impl.AggregatedPageImpl;
import org.springframework.data.elasticsearch.core.mapping.ElasticsearchPersistentEntity;
import org.springframework.data.elasticsearch.core.mapping.ElasticsearchPersistentProperty;
import org.springframework.data.mapping.context.MappingContext;
import org.springframework.util.Assert;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.nio.charset.Charset;
import java.util.*;
import java.util.concurrent.ConcurrentHashMap;

/**
 * @author weizhiwen
 * @date 2018/10/18
 */
@Slf4j
public class ZwResultMapper extends AbstractResultMapper {
    /**
     * score set 方法缓存
     */
    private static final Map<Class, List<Method>> SCORE_SET_METHOD_CACHE = new ConcurrentHashMap<>();

    public static final String SET = "set";
    private MappingContext<? extends ElasticsearchPersistentEntity<?>, ElasticsearchPersistentProperty> mappingContext;

    public ZwResultMapper() {
        super(new DefaultEntityMapper());
    }

    public ZwResultMapper(MappingContext<? extends ElasticsearchPersistentEntity<?>, ElasticsearchPersistentProperty> mappingContext) {
        super(new DefaultEntityMapper());
        this.mappingContext = mappingContext;
    }

    public ZwResultMapper(EntityMapper entityMapper) {
        super(entityMapper);
    }

    public ZwResultMapper(
            MappingContext<? extends ElasticsearchPersistentEntity<?>, ElasticsearchPersistentProperty> mappingContext,
            EntityMapper entityMapper) {
        super(entityMapper);
        this.mappingContext = mappingContext;
    }

    @Override
    public <T> AggregatedPage<T> mapResults(SearchResponse response, Class<T> clazz, Pageable pageable) {
        long totalHits = response.getHits().getTotalHits();
        List<T> results = new ArrayList<>();
        for (SearchHit hit : response.getHits()) {
            if (hit != null) {
                T result = null;
                if (StringUtils.isNotBlank(hit.getSourceAsString())) {
                    result = mapEntity(hit.getSourceAsString(), clazz);
                } else {
                    result = mapEntity(hit.getFields().values(), clazz);
                }
                //增加的代码
                setEntityScore(result, hit.getScore(), clazz);
                setPersistentEntityId(result, hit.getId(), clazz);
                setPersistentEntityVersion(result, hit.getVersion(), clazz);
                populateScriptFields(result, hit);
                results.add(result);
            }
        }

        return new AggregatedPageImpl<>(results, pageable, totalHits);
    }

    private <T> void populateScriptFields(T result, SearchHit hit) {
        if (hit.getFields() != null && !hit.getFields().isEmpty() && result != null) {
            for (java.lang.reflect.Field field : result.getClass().getDeclaredFields()) {
                ScriptedField scriptedField = field.getAnnotation(ScriptedField.class);
                if (scriptedField != null) {
                    String name = scriptedField.name().isEmpty() ? field.getName() : scriptedField.name();
                    SearchHitField searchHitField = hit.getFields().get(name);
                    if (searchHitField != null) {
                        field.setAccessible(true);
                        try {
                            field.set(result, searchHitField.getValue());
                        } catch (IllegalArgumentException e) {
                            throw new ElasticsearchException("failed to set scripted field: " + name + " with value: "
                                    + searchHitField.getValue(), e);
                        } catch (IllegalAccessException e) {
                            throw new ElasticsearchException("failed to access scripted field: " + name, e);
                        }
                    }
                }
            }
        }
    }

    private <T> T mapEntity(Collection<SearchHitField> values, Class<T> clazz) {
        return mapEntity(buildJSONFromFields(values), clazz);
    }

    private String buildJSONFromFields(Collection<SearchHitField> values) {
        JsonFactory nodeFactory = new JsonFactory();
        try {
            ByteArrayOutputStream stream = new ByteArrayOutputStream();
            JsonGenerator generator = nodeFactory.createGenerator(stream, JsonEncoding.UTF8);
            generator.writeStartObject();
            for (SearchHitField value : values) {
                if (value.getValues().size() > 1) {
                    generator.writeArrayFieldStart(value.getName());
                    for (Object val : value.getValues()) {
                        generator.writeObject(val);
                    }
                    generator.writeEndArray();
                } else {
                    generator.writeObjectField(value.getName(), value.getValue());
                }
            }
            generator.writeEndObject();
            generator.flush();
            return new String(stream.toByteArray(), Charset.forName("UTF-8"));
        } catch (IOException e) {
            return null;
        }
    }

    @Override
    public <T> T mapResult(GetResponse response, Class<T> clazz) {
        T result = mapEntity(response.getSourceAsString(), clazz);
        if (result != null) {
            setPersistentEntityId(result, response.getId(), clazz);
            setPersistentEntityVersion(result, response.getVersion(), clazz);
        }
        return result;
    }

    @Override
    public <T> LinkedList<T> mapResults(MultiGetResponse responses, Class<T> clazz) {
        LinkedList<T> list = new LinkedList<>();
        for (MultiGetItemResponse response : responses.getResponses()) {
            if (!response.isFailed() && response.getResponse().isExists()) {
                T result = mapEntity(response.getResponse().getSourceAsString(), clazz);
                setPersistentEntityId(result, response.getResponse().getId(), clazz);
                setPersistentEntityVersion(result, response.getResponse().getVersion(), clazz);
                list.add(result);
            }
        }
        return list;
    }

    private <T> void setPersistentEntityId(T result, String id, Class<T> clazz) {

        if (mappingContext != null && clazz.isAnnotationPresent(Document.class)) {

            ElasticsearchPersistentEntity<?> persistentEntity = mappingContext.getPersistentEntity(clazz);
            ElasticsearchPersistentProperty idProperty = persistentEntity.getIdProperty();

            // Only deal with String because ES generated Ids are strings !
            if (idProperty != null && idProperty.getType().isAssignableFrom(String.class)) {
                persistentEntity.getPropertyAccessor(result).setProperty(idProperty, id);
            }

        }
    }

    private <T> void setEntityScore(T result, float score, Class<T> clazz) {
        if (result != null && clazz.isAnnotationPresent(Document.class)) {
            List<Method> methods;
            if (SCORE_SET_METHOD_CACHE.containsKey(clazz)) {
                methods = SCORE_SET_METHOD_CACHE.get(clazz);
            } else {
                methods = new Vector<>();
                for (Method method : clazz.getMethods()) {
                    if (StringUtils.startsWith(method.getName(), SET) && hasAnnotation(clazz, method)) {
                        if (method.getParameterCount() == 1) {
                            if (Float.class.equals(method.getParameterTypes()[0])) {
                                methods.add(method);
                            }
                        }
                    }
                }
                SCORE_SET_METHOD_CACHE.put(clazz, methods);
            }
            for (Method method : methods) {
                try {
                    method.invoke(result, score);
                } catch (Exception e) {
                    log.error("{} set score error", clazz.getSimpleName());
                }
            }
        }
    }

    public boolean hasAnnotation(Class<?> clazz, Method method) {
        if (method.getAnnotation(Score.class) != null) {
            return true;
        }
        String findFieldName = StringUtils.removeStart(method.getName(), "set");
        for (Field field : clazz.getDeclaredFields()) {
            if (field.getName().equalsIgnoreCase(findFieldName) && field.getAnnotation(Score.class) != null) {
                return true;
            }
        }
        return false;
    }

    private <T> void setPersistentEntityVersion(T result, long version, Class<T> clazz) {
        if (mappingContext != null && clazz.isAnnotationPresent(Document.class)) {

            ElasticsearchPersistentEntity<?> persistentEntity = mappingContext.getPersistentEntity(clazz);
            ElasticsearchPersistentProperty versionProperty = persistentEntity.getVersionProperty();

            // Only deal with Long because ES versions are longs !
            if (versionProperty != null && versionProperty.getType().isAssignableFrom(Long.class)) {
                // check that a version was actually returned in the response, -1 would indicate that
                // a search didn't request the version ids in the response, which would be an issue
                Assert.isTrue(version != -1, "Version in response is -1");
                persistentEntity.getPropertyAccessor(result).setProperty(versionProperty, version);
            }
        }
    }
}

定制ElasticsearchTemplate，把org.springframework.data.elasticsearch.core.DefaultResultMapper改成ZwResultMapper


import org.elasticsearch.client.Client;
import org.springframework.data.elasticsearch.core.ElasticsearchTemplate;
import org.springframework.data.elasticsearch.core.EntityMapper;
import org.springframework.data.elasticsearch.core.ResultsMapper;
import org.springframework.data.elasticsearch.core.convert.ElasticsearchConverter;

/**
 * @author weizhiwen
 * @date 2018/7/4
 */
public class ZwElasticsearchTemplate extends ElasticsearchTemplate {


    public ZwElasticsearchTemplate(Client client) {
        super(client);
    }

    public ZwElasticsearchTemplate(Client client, EntityMapper entityMapper) {
        super(client, entityMapper);
    }

    public ZwElasticsearchTemplate(Client client, ElasticsearchConverter elasticsearchConverter, EntityMapper entityMapper) {
        this(client, elasticsearchConverter,
                new ZwResultMapper(elasticsearchConverter.getMappingContext(), entityMapper));
    }

    public ZwElasticsearchTemplate(Client client, ResultsMapper resultsMapper) {
        super(client, resultsMapper);
    }

    public ZwElasticsearchTemplate(Client client, ElasticsearchConverter elasticsearchConverter) {
        this(client, elasticsearchConverter, new ZwResultMapper(elasticsearchConverter.getMappingContext()));
    }

    public ZwElasticsearchTemplate(Client client, ElasticsearchConverter elasticsearchConverter, ResultsMapper resultsMapper) {
        super(client, elasticsearchConverter, resultsMapper);
    }
}

    @Bean
    public ElasticsearchTemplate elasticsearchTemplate(Client client, ElasticsearchConverter converter) {
        try {
            return new ZwElasticsearchTemplate(client, converter);
        } catch (Exception var4) {
            throw new IllegalStateException(var4);
        }
    }

使用

类加上@Document字段加上@Score并且类型为Float

import lombok.Data;
import org.springframework.data.elasticsearch.annotations.Document;

/**
 * @author weizhiwen
 * @date 2018/10/18
 */
@Data
@Document(indexName = "asd")
public class AudioDocumentDTO extends BaseAudioDocument {
    @Score
    private Float score;
}

Spring Boot集成Elasticsearch自定义序列化

使用

相关文章

网友评论

延伸阅读

深度阅读

栏目导航

热点阅读