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SpringBoot 集成 Nebula的操作过程

2024-05-25 14:19:17 作者：一个高效工作的家伙

这篇文章主要介绍了SpringBoot 集成 Nebula的操作过程,通过示例代码介绍了java 环境下如何对 Nebula Graph 进行操作,感兴趣的朋友跟随小编一起看看吧

工作需求，开始了解图数据库，经过工具选型，最终选择nebula graph，并集成到springboot，java 环境下如何对 Nebula Graph 进行操作，本文整理下过程。

1、首先引入 pom 依赖

<dependency>
    <groupId>com.vesoft</groupId>
    <artifactId>client</artifactId>
    <version>3.0.0</version>
</dependency>

为方便解析 json ，这里把 fastjson 也引进来。

<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>fastjson</artifactId>
    <version>1.2.78</version>
</dependency>

2、配置文件中配置 Nebula 的信息

nebula:
  address[0]:
    host: 192.168.40.130
    port: 9669
  username: root
  password: root
  reconnect: false
  space: javatest

3、java配置过程，文件结构如下：

1）声明 NebulaProperties 接收上面的配置信息：

@Data
public class NebulaAddress {
    private String host;
    private Integer port;
}

@Data
@Configuration
@ConfigurationProperties(prefix = "nebula")
public class NebulaProperties {
    private List<NebulaAddress> address;
    private String username;
    private String password;
    private boolean reconnect;
    private String space;
}

2）声明 NebulaConstant 把常用的字符串声明在这里：

public class NebulaConstant {
    public static final String USE = "USE ";
    public static final String SEMICOLON = "; ";
    public static final String ERROR_CODE = "-1";
    @Getter
    @AllArgsConstructor
    public enum NebulaJson{
        ERRORS("errors"),
        CODE("code"),
        MESSAGE("message"),
        RESULTS("results"),
        COLUMNS("columns"),
        DATA("data"),
        ROW("row");
        private String key;
    }
}

3）声明 NebulaConfig ，初始化 NebulaPool ，及声明 Session 的获取方式：

便对结果的解析，再声明一个 NebulaResult 用来接收结果：

@Data
public class NebulaResult<T> {
    private Integer code;
    private String message;
    private List<T> data;
    public boolean isSuccessed(){
        return code == 0;
    }
}

4）为了方便对结果的解析，再声明一个 NebulaResult 用来接收结果：

@Data
public class NebulaResult<T> {
    private Integer code;
    private String message;
    private List<T> data;
    public boolean isSuccessed(){
        return code == 0;
    }
}

5）每次都是使用 Session 未免太麻烦，这里封装一个 NebulaTemplate 返回上面对象：

@Slf4j
@Component
public class NebulaTemplate {
    @Resource
    Session session;
    public <T> NebulaResult<T> queryObject(String stmt, Class<T> tClass) {
        NebulaResult<T> nebulaResult = executeObject(stmt);
        if (Objects.isNull(nebulaResult.getData())) {
            return nebulaResult;
        }
        Optional.ofNullable(nebulaResult.getData()).ifPresent(data -> nebulaResult.setData(data.stream().map(d -> JSONObject.toJavaObject(((JSONObject) d), tClass)).collect(Collectors.toList())));
        return nebulaResult;
    }
    public NebulaResult executeObject(String stmt) {
        JSONObject jsonObject = executeJson(stmt);
        return JSONObject.toJavaObject(jsonObject, NebulaResult.class);
    }
    public JSONObject executeJson(String stmt) {
        JSONObject restJson = new JSONObject();
        try {
            JSONObject jsonObject = JSON.parseObject(Objects.requireNonNull(session).executeJson(stmt));
            JSONObject errors = jsonObject.getJSONArray(NebulaConstant.NebulaJson.ERRORS.getKey()).getJSONObject(0);
            restJson.put(NebulaConstant.NebulaJson.CODE.getKey(), errors.getInteger(NebulaConstant.NebulaJson.CODE.getKey()));
            if (errors.getInteger(NebulaConstant.NebulaJson.CODE.getKey()) != 0) {
                restJson.put(NebulaConstant.NebulaJson.MESSAGE.getKey(), errors.getString(NebulaConstant.NebulaJson.MESSAGE.getKey()));
                return restJson;
            }
            JSONObject results = jsonObject.getJSONArray(NebulaConstant.NebulaJson.RESULTS.getKey()).getJSONObject(0);
            JSONArray columns = results.getJSONArray(NebulaConstant.NebulaJson.COLUMNS.getKey());
            if (Objects.isNull(columns)) {
                return restJson;
            }
            JSONArray data = results.getJSONArray(NebulaConstant.NebulaJson.DATA.getKey());
            if (Objects.isNull(data)) {
                return restJson;
            }
            List<JSONObject> resultList = new ArrayList<>();
            data.stream().map(d -> (JSONObject) d).forEach(d -> {
                JSONArray row = d.getJSONArray(NebulaConstant.NebulaJson.ROW.getKey());
                JSONObject map = new JSONObject();
                for (int i = 0; i < columns.size(); i++) {
                    map.put(columns.getString(i), row.get(i));
                }
                resultList.add(map);
            });
            restJson.put(NebulaConstant.NebulaJson.DATA.getKey(), resultList);
        } catch (Exception e) {
            restJson.put(NebulaConstant.NebulaJson.CODE.getKey(), NebulaConstant.ERROR_CODE);
            restJson.put(NebulaConstant.NebulaJson.MESSAGE.getKey(), e.toString());
            log.error("nebula execute err：", e);
        }
        return restJson;
    }
}

4、测试

@RestController
public class TestController {
    @Resource
    NebulaTemplate nebulaTemplate;
    @GetMapping("/addVertex")
    public Object addJSON() throws IOErrorException {
        String sql = "insert vertex team(team_name, persion_num) values \"team_2\":(\"team_2\", 43);";
        NebulaResult nebulaResult = nebulaTemplate.executeObject(sql);
        return nebulaResult;
    }
    @GetMapping("/findVertex")
    public Object findJson2() throws IOErrorException {
        String sql = "lookup on team  yield id(vertex) AS id,properties(vertex).persion_num AS persion_num,properties(vertex).team_name AS team_name;";
        NebulaResult<Info> infoNebulaResult = nebulaTemplate.queryObject(sql, Info.class);
        return infoNebulaResult;
    }
}

5、常用的nSQL语句

//查看所有边
LOOKUP ON follow YIELD edge AS e;
//搜索点
LOOKUP ON entity WHERE entity.name == "20元的东西" YIELD properties(vertex).name as name, properties(vertex).cntt as cntt, properties(vertex).sid as sid, properties(vertex).syspath as syspath;
//由一点查看关联的所有点
GO  FROM "20元的东西" OVER follow BIDIRECT YIELD dst(edge) AS destination;
//查全部点
MATCH (v) RETURN v limit 100;
//以下是删除所有的边
LOOKUP ON follow YIELD src(edge) AS src, dst(edge) AS dst 
      |   DELETE EDGE follow $-.src -> $-.dst @0;
//从一点批量删除边
GO FROM "20元的东西" OVER * BIDIRECT 
        YIELD src(edge) AS src, dst(edge) AS dst 
        | DELETE EDGE follow $-.src -> $-.dst @0;
//批量删除点
LOOKUP ON entity YIELD id(vertex)  as id
    | DELETE VERTEX $-.id;
//复合查询
LOOKUP ON entity WHERE entity.name == "20元的东西" YIELD id(vertex) as id | 
  GO  FROM $-.id OVER follow 
  YIELD dst(edge) AS id | 
  GO FROM $-.id OVER follow 
  WHERE properties($$).name == "20元的东西的子节点" 
  YIELD properties($$) as obj;

到此这篇关于SpringBoot 集成 Nebula的文章就介绍到这了,更多相关SpringBoot 集成 Nebula内容请搜索脚本之家以前的文章或继续浏览下面的相关文章希望大家以后多多支持脚本之家！

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