Spring Integration
将 ReactiveMongoTemplate 的映射、集合命名和反应式生命周期与 MongoExecutionContext 适配器连接,而不引入 Spring Data MongoDB 作为核心依赖。
Spring Data MongoDB 由应用程序维护
build.gradle
textdependencies {
implementation("com.byeolnaerim:reactive-mongo-dsl:1.0.0")
implementation("org.springframework.boot:spring-boot-starter-data-mongodb-reactive")
}核心库不直接依赖 Spring Data MongoDB。要使用现有 Spring 应用程序的 ReactiveMongoTemplate 设置,需在应用层提供 MongoExecutionContext 适配器。
SpringReactiveMongoExecutionContext 适配器
SpringReactiveMongoExecutionContext.java
javapublic class SpringReactiveMongoExecutionContext implements MongoExecutionContext {
private final ReactiveMongoTemplate reactiveMongoTemplate;
private final MongoClient mongoClient;
private final MongoConverter mongoConverter;
private final ReactiveEntityCallbacks entityCallbacks;
public SpringReactiveMongoExecutionContext(
ReactiveMongoTemplate reactiveMongoTemplate,
MongoClient mongoClient,
ReactiveEntityCallbacks entityCallbacks
) {
this.reactiveMongoTemplate = Objects.requireNonNull(reactiveMongoTemplate);
this.mongoClient = Objects.requireNonNull(mongoClient);
this.mongoConverter = reactiveMongoTemplate.getConverter();
this.entityCallbacks = Objects.requireNonNull(entityCallbacks);
}
@Override
public Mono<MongoDatabase> getDatabase() {
return reactiveMongoTemplate.getMongoDatabase();
}
@Override
public Mono<ClientSession> startSession() {
return Mono.from(mongoClient.startSession());
}
@Override
public String getCollectionName(Class<?> entityClass) {
return reactiveMongoTemplate.getCollectionName(entityClass);
}
@Override
public Document write(Object source) {
Document document = new Document();
mongoConverter.write(source, document);
return document;
}
@Override
public <T> T read(Class<T> targetType, Document source) {
return mongoConverter.read(targetType, source);
}
@Override
public Object getId(Object entity) {
MongoPersistentEntity<?> persistentEntity =
mongoConverter.getMappingContext().getPersistentEntity(entity.getClass());
if (persistentEntity == null || !persistentEntity.hasIdProperty()) {
return null;
}
Object id = persistentEntity.getIdentifierAccessor(entity).getIdentifier();
if (id == null) return null;
Document document = new Document();
mongoConverter.write(entity, document);
return document.get("_id");
}
@Override
@SuppressWarnings({ "rawtypes", "unchecked" })
public void setId(Object entity, Object id) {
MongoPersistentEntity persistentEntity =
mongoConverter.getMappingContext().getPersistentEntity(entity.getClass());
if (persistentEntity == null || !persistentEntity.hasIdProperty()) return;
MongoPersistentProperty idProperty =
(MongoPersistentProperty) persistentEntity.getRequiredIdProperty();
Object targetId = id;
if (id instanceof ObjectId objectId && idProperty.getType() == String.class) {
targetId = objectId.toHexString();
} else if (
id != null
&& !idProperty.getType().isInstance(id)
&& mongoConverter.getConversionService()
.canConvert(id.getClass(), idProperty.getType())
) {
targetId = mongoConverter.getConversionService()
.convert(id, idProperty.getType());
}
PersistentPropertyAccessor accessor = persistentEntity.getPropertyAccessor(entity);
accessor.setProperty(idProperty, targetId);
}
@Override
public <T> Mono<T> beforePersist(T entity, String collectionName) {
return entityCallbacks.callback(
ReactiveBeforeConvertCallback.class,
entity,
collectionName
);
}
@Override
public <T> Mono<T> afterPersist(
T entity,
Document document,
String collectionName
) {
return entityCallbacks.callback(
ReactiveAfterSaveCallback.class,
entity,
document,
collectionName
);
}
@Override
public Object getSessionScope() {
return mongoClient;
}
@Override
public Object getNative() {
return reactiveMongoTemplate;
}
@Override
public <T> T getNative(Class<T> nativeType) {
if (nativeType.isInstance(reactiveMongoTemplate)) {
return nativeType.cast(reactiveMongoTemplate);
}
if (nativeType.isInstance(mongoClient)) {
return nativeType.cast(mongoClient);
}
return MongoExecutionContext.super.getNative(nativeType);
}
}在实际实现中,向上述类添加所需的 Spring/MongoDB 导入。关键是将实体的读/写与 MongoConverter、集合名称与 ReactiveMongoTemplate、会话启动与相应的 MongoClient 连接起来。
Resolver 和 DSL Bean 注册
MongoTemplateNameResolver.java
java@Component
public class MongoTemplateNameResolver
implements MongoTemplateResolver<MongoTemplateName> {
private final MongoExecutionContext frontExecutionContext;
private final MongoExecutionContext backExecutionContext;
public MongoTemplateNameResolver(
@Qualifier("frontMongoTemplate") ReactiveMongoTemplate frontTemplate,
@Qualifier("frontMongoClient") MongoClient frontMongoClient,
@Qualifier("backMongoTemplate") ReactiveMongoTemplate backTemplate,
@Qualifier("backMongoClient") MongoClient backMongoClient,
ApplicationContext applicationContext
) {
ReactiveEntityCallbacks callbacks =
ReactiveEntityCallbacks.create(applicationContext);
this.frontExecutionContext = new SpringReactiveMongoExecutionContext(
frontTemplate, frontMongoClient, callbacks
);
this.backExecutionContext = new SpringReactiveMongoExecutionContext(
backTemplate, backMongoClient, callbacks
);
}
@Override
public MongoExecutionContext getTemplate(MongoTemplateName key) {
return switch (key) {
case FRONT -> frontExecutionContext;
case BACK -> backExecutionContext;
};
}
}ReactiveMongoDslConfiguration.java
java@Bean
public ReactiveMongoDsl<MongoTemplateName> reactiveMongoDsl(
MongoTemplateResolver<MongoTemplateName> resolver
) {
return new ReactiveMongoDsl<>(resolver);
}适配器连接的范围
@Document / 集合名称
使用 ReactiveMongoTemplate#getCollectionName(...)。
@Id / @Field / 自定义转换
使用 MongoConverter 进行实体 ↔ Document 转换。
反应式审计
将 beforePersist(...) 连接到 ReactiveBeforeConvertCallback,在 save() 系列中应用反应式审计回调。
ReactiveAfterSaveCallback
在写入成功后可以在 afterPersist(...) 中调用。
Spring QueryMapper
不适用。DSL 字符串字段路径基于实际 MongoDB 文档字段名称。
Spring DataAccessException
不自动转换。实际操作由 Reactive Streams Driver 执行。
使用 @Field 的情况
@Field("user_name")
private String userName;
// MongoDB document field 이름을 사용
.fields(pair("user_name", "kim"))实体保存/查询转换应用 Spring 映射,但 DSL 条件的字符串路径不经过 Spring QueryMapper。但准确的 id 路径段会根据 DSL 自身规则规范化为 _id。