java - 通过 Spring Boot Rest API 查询 mongodb 集合以分页格式返回结果

Question

Mongo 中存在一个具有一些属性的集合。每当引擎中发生任何事务时，都会保存此信息。我需要一个 API，使用户能够通过以下属性的一个或多个组合来搜索 AnaysisJob:• 开始者•startAt(我们需要“from”和“to”，并且我们使用 Between 子句进行搜索)。• 状态。

用户可以使用单个属性或上述属性的组合进行搜索。如果使用组合，则必须进行“AND”运算。

不要忘记，它也必须支持分页。

以下是类(class):

AnalysisJobSearchCriteria.java

@Data
@Document
public class AnalysisJobSearchCriteria {
    private Long startedAt = System.currentTimeMillis();
    private String startedBy;
    private AnalysisJobStatusType status;
}

AnalysisJobResource.java

@Slf4j
@Api(value = "Analysis Job Resource", tags = "CONNECTIONS")
@RestController
@RequestMapping("/api/v1")
public class AnalysisJobResource {

    @Autowired
    private AnalysisJobSearchService analysisJobSearchService;

    @ApiOperation(value = "Analysis", response = Map.class)
    @ApiResponses({
            @ApiResponse(code = 400, message = "Bad Request"),
            @ApiResponse(code = 404, message = "Not found"),
            @ApiResponse(code = 200, message = "OK")
    })
    @PostMapping(value = "/analysis-job", produces = MediaType.APPLICATION_JSON_VALUE)
    public ResponseEntity<?> searchAnalysisJob(@RequestBody final AnalysisJobSearchCriteria analysisJobSearchCriteria) {
        AggregationResults<AnalysisJobResource> analysisJob = analysisJobSearchService.searchAnalysisJobs(analysisJobSearchCriteria);
        return new ResponseEntity<>(analysisJob, HttpStatus.OK);
    }
}

AnalysisJobSearchService.java

@Service
public class AnalysisJobSearchService {

    private final AnalysisJobCustomRepositoryImpl analysisJobCustomRepositoryImpl;

     @Autowired
        public AnalysisJobSearchService(final AnalysisJobCustomRepositoryImpl analysisJobCustomRepositoryImpl) {
            this.analysisJobCustomRepositoryImpl = analysisJobCustomRepositoryImpl;
        }

    public AggregationResults<AnalysisJobResource> searchAnalysisJobs(AnalysisJobSearchCriteria analysisJobSearchCriteria) {
        AggregationResults<AnalysisJobResource> analysisJob = analysisJobCustomRepositoryImpl.searchAnalysisJob(analysisJobSearchCriteria);
        return analysisJob;
    }

}

AnalysisJobCustomRepository.java

@SuppressWarnings("unchecked")
@Override
public AggregationResults<AnalysisJobResource> searchAnalysisJob(AnalysisJobSearchCriteria analysisJobSearchCriteria) {
    MatchOperation salaryMatch = null;
    if (!analysisJobSearchCriteria.getStatus().equals(null)) {
    salaryMatch = Aggregation.match(new Criteria("status").is(analysisJobSearchCriteria.getStatus()));
    }

    Aggregation aggregation = Aggregation.newAggregation(salaryMatch);

    AggregationResults<AnalysisJobResource> result = mongoTemplate.aggregate(
            aggregation, "result", AnalysisJobResource.class);
    return result;
}

这些是我的一些类(class)。我还有一个 Connection 类来与我的数据库建立连接，并且连接工作正常。只是我无法提出一个查询以及 mongo 模板来让我的场景工作。

由于我刚开始使用 Mongo 和 Spring Boot，因此我们将不胜感激。另外，我相信如果服务返回 List 而不是 AggregationResult 会更好。但是如何在 Java 中为 Mongo 创建查询让我很困惑。

Answer 1

您可以使用 AggregationOperation 来解决此问题

private List<SearcheableEntity> searchSmth(CustomCriteria criteria){

  List<AggregationOperation> operations = new ArrayList<>();

  //it's simple way, better pattern is to create criteria builder, 
  //witch will create Criteria.class object from request params
  operations.add(Aggregation.match(Criteria.where("name").is(criteria.getName());

  //For pagination skip and limit methods can be used
  operations.add(Aggregation.skip(criteria.getOffset() != null ? criteria.getOffset() : 0));
  operations.add(Aggregation.limit(criteria.getLimit() != null ? criteria.getLimit() : Integer.MAX_VALUE));

  return mongoTemplate
                .aggregate(Aggregation.newAggregation(operations),
                           "Collection_name", 
                           SearcheableEntity.class
                ).getMappedResults();
}

此外，如果您需要在搜索中使用逻辑“或”或“与”，您可以以此类模式创建搜索条件

new Criteria().andOperator(firstCrinteria, ..., lastCriteria)
new Criteria().orOperator(firstCrinteria, ..., lastCriteria)

举个例子

SuppressWarnings("unchecked")
@Override
public List<AnalysisJobResource> searchAnalysisJob(AnalysisJobSearchCriteria criteria) {
  List<AggregationOperation> operations = new ArrayList<>();

  if (!criteria.getStatus() != null) {
     operations.add(Aggregation.match(Criteria.where("status").is(criteria.getStatus())));
  }
  if(!criteria.getStartedAt().equals(null)){ 
  operations.add(Aggregation.match(Criteria.where("time").gt(criteria.getStartedAt()));
  }

return mongoTemplate.aggregate(
        Aggregation.newAggregation(operations), "result", AnalysisJobResource.class).getMappedResults();

}