SDN/RX 自定义查询@RelationshipProperties 映射深度

Question

我遇到了 SDN/RX 1.1

的问题

        <dependency>
            <groupId>org.neo4j.springframework.data</groupId>
            <artifactId>spring-data-neo4j-rx-spring-boot-starter</artifactId>
            <version>1.1.1</version>
        </dependency>

在 存储库 class 上使用自定义查询并尝试查询与属性的多个关系时。

我有两个关系属性：

@RelationshipProperties
public class InRegionProperties {

  @Id
  @GeneratedValue
  private Long id;
  private String location;
  private int distance;

  public InRegionProperties (String location, int distance) {
    this.id=null;
    this.location = location;
    this.distance = distance;
  }

  public Long getId () {
    return id;
  }

  public String getLocation () {
    return location;
  }

  public int getDistance () {
    return distance;
  }

  public void setLocation (String location) {
    this.location = location;
  }

  public void setDistance (int distance) {
    this.distance = distance;
  }

  public void setId (Long id) {
    this.id = id;
  }
}

和

@RelationshipProperties
public class InWorldProperties {

  @Id
  @GeneratedValue
  private Long id;
  private String location;

  public InWorldProperties (String location) {
    this.id=null;
    this.location = location;
  }

  public Long getId () {
    return id;
  }

  public String getLocationInWorld () {
    return location;
  }

  public void setLocationInWorld (String location) {
    this.location = location;
  }

  public void setId (Long id) {
    this.id = id;
  }
}

对于两个节点，一个区域节点和一个World节点。我有一个最后一个节点，一个 Lieu 节点，都是这样关联的：

(l:Lieu)-[:IN_REGION{location, distance}]->(r:Region)-[:IN_WORLD{位置}]->(w:世界)

然后我使用 WorldRepository 上的自定义查询来获取世界中的区域，然后获取区域中的 lieux。

@Query("MATCH (r:`Region`)-[:IN_WORLD]->(n:`World`) WHERE id(r)=$regionId WITH n, id(n) AS __internalNeo4jId__ "
      + "RETURN n{.description, __internalNeo4jId__: id(n), .name, __nodeLabels__: labels(n), "
      + "World_IN_WORLD_Region:[(n)<-[__relationship__:IN_WORLD]-(n_regions:Region) | n_regions{.description, __internalNeo4jId__: id(n_regions), .name, __nodeLabels__: labels(n_regions), "
      + "Region_IN_REGION_Lieu: [(n_regions)<-[__relationship__:`IN_REGION`]-(n_regions_lieux:Lieu) | n_regions_lieux{.description, __internalNeo4jId__: id(n_regions_lieux), .name, __nodeLabels__: labels(n_regions_lieux), __relationship__}], __relationship__}]"
      + "}")
  Mono<World> getByRegion(Long regionId);

这就是问题所在：

要获取所有 relationsipProperties，似乎 SDN/RX 映射引擎只接受 relationship 作为关系的别名。此查询在 Cypher（Neo4j 浏览器）中的结果是：

{
  "name": "New Finn City",
  "description": "Ville Monde, terre de la Ligue Des Héros.",
  "__internalNeo4jId__": 61,
  "World_IN_WORLD_Region": [
    {
      "__internalNeo4jId__": 14,
      "__relationship__": {
"identity": 4,
"start": 14,
"end": 61,
"type": "IN_WORLD",
"properties": {
"location": "Sud Est"
        }
      },
      "name": "Bio Town",
      "description": "Le quartier réserve naturelle. La biosphère, en constante évolution grâce au Weillenium, y est préservée et vit en liberté protégée et surveillée.",
      "Region_IN_REGION_Lieu": [],
      "__nodeLabels__": [
        "Region"
      ]
    },
    {
      "__internalNeo4jId__": 15,
      "__relationship__": {
"identity": 3,
"start": 15,
"end": 61,
"type": "IN_WORLD",
"properties": {
"location": "Nord"
        }
      },
      "name": "Astro Town",
      "description": null,
      "Region_IN_REGION_Lieu": [],
      "__nodeLabels__": [
        "Region"
      ]
    },
    {
      "__internalNeo4jId__": 13,
      "__relationship__": {
"identity": 2,
"start": 13,
"end": 61,
"type": "IN_WORLD",
"properties": {
"location": "Est"
        }
      },
      "name": "Electro Town",
      "description": "Le quartier des savants et inventeurs, où les robots et machines alimentées en Weillenium sont omniprésentes.",
      "Region_IN_REGION_Lieu": [],
      "__nodeLabels__": [
        "Region"
      ]
    },
    {
      "__internalNeo4jId__": 12,
      "__relationship__": {
"identity": 1,
"start": 12,
"end": 61,
"type": "IN_WORLD",
"properties": {
"location": "Nord Ouest"
        }
      },
      "name": "Dark Town",
      "description": "Le quartier pauvre, rongé par la criminalité, et le traffic de Weillenium. C'est le territoire de la Ligue des Villains.",
      "Region_IN_REGION_Lieu": [],
      "__nodeLabels__": [
        "Region"
      ]
    },
    {
      "__internalNeo4jId__": 11,
      "__relationship__": {
"identity": 0,
"start": 11,
"end": 61,
"type": "IN_WORLD",
"properties": {
"location": "Sud Ouest"
        }
      },
      "name": "Atom Town",
      "description": "Le quartier central de New Finn City, où siège la Ligue des Héros. C'est le centre administratif du monde.",
      "Region_IN_REGION_Lieu": [],
      "__nodeLabels__": [
        "Region"
      ]
    }
  ],
  "__nodeLabels__": [
    "World"
  ]
}

Lieux 节点由于重复使用 relationship 作为别名。当在 cypher 上为 :IN_REGION 关系使用另一个别名时，我得到了获取的 Lieux，但在 SDN/RX 中我得到以下错误：

Caused by: org.neo4j.driver.exceptions.value.Uncoercible: Cannot coerce NULL to Relationship
    at org.neo4j.driver.internal.value.ValueAdapter.asRelationship(ValueAdapter.java:311)
    at org.neo4j.springframework.data.core.mapping.DefaultNeo4jConverter.createInstanceOfRelationships(DefaultNeo4jConverter.java:499)
    at org.neo4j.springframework.data.core.mapping.DefaultNeo4jConverter.lambda$populateFrom(DefaultNeo4jConverter.java:375)
    at org.springframework.data.mapping.model.BasicPersistentEntity.doWithAssociations(BasicPersistentEntity.java:380)
    at org.neo4j.springframework.data.core.mapping.DefaultNeo4jConverter.map(DefaultNeo4jConverter.java:288)
    at org.neo4j.springframework.data.core.mapping.DefaultNeo4jConverter.lambda$createInstanceOfRelationships(DefaultNeo4jConverter.java:496)
    at org.neo4j.springframework.data.core.mapping.DefaultNeo4jConverter$KnownObjects.computeIfAbsent(DefaultNeo4jConverter.java:566)
    at org.neo4j.springframework.data.core.mapping.DefaultNeo4jConverter.createInstanceOfRelationships(DefaultNeo4jConverter.java:495)
    at org.neo4j.springframework.data.core.mapping.DefaultNeo4jConverter.lambda$populateFrom(DefaultNeo4jConverter.java:375)
    at org.springframework.data.mapping.model.BasicPersistentEntity.doWithAssociations(BasicPersistentEntity.java:380)
    at org.neo4j.springframework.data.core.mapping.DefaultNeo4jConverter.map(DefaultNeo4jConverter.java:288)
    at org.neo4j.springframework.data.core.mapping.DefaultNeo4jConverter.read(DefaultNeo4jConverter.java:138)
    ... 48 more

映射引擎似乎只接受 relationship 作为关系的别名，该关系具有要在 @RelationshipProperties 中映射的属性 class.

有没有办法绕过这个问题？

谢谢大家的帮助。

Answer 1

首先要做的事情是：现在已经有了正式的 SDN 6，它是 SDN/RX 的后继者。我们在半年前停止了 SDN/RX 的开发，并专注于新的 SDN。 SDN 6 可用于 Spring 从 2.4 版开始的引导。

命名为 big 的关系是我们在过去几个月中修复的问题。

如果你实在没机会更新，我可以看看。如果需要，请添加评论。

SDN/RX 自定义查询@RelationshipProperties 映射深度

SDN/RX Custom Query @RelationshipProperties mapping depth

neo4j

spring-data-neo4j

spring-boot