如何使用Spring Data Solr做空间检索并排序

解决方法一

To set fl you have to use query.addProjectionOnField(String fieldname).

    SimpleQuery query = new SimpleQuery(conditions);
    query.addProjectionOnField("*");
    query.addProjectionOnField("score");

For mapping score into EventDocument you’ll have to add the property as follows.

    @Indexed(value = "score", readonly = true)
    private Float score;

Unfortunately there seems to be an issue with geodist() that might be caused by the way spring data solr creates spatial query. Opended DATASOLR-130 for that.

Distance can be requested using SolrCallback along with SolrTemplate by setting spatial paramters yourself.

 SimpleQuery query = new SimpleQuery(conditions);
    query.addProjectionOnField("*");
    query.addProjectionOnField("distance:geodist()");

    DefaultQueryParser qp = new DefaultQueryParser();
    final SolrQuery solrQuery = qp.constructSolrQuery(query);
    solrQuery.add("sfield", "store");
    solrQuery.add("pt", GeoConverters.GeoLocationToStringConverter.INSTANCE.convert(new GeoLocation(45.15, -93.85)));
    solrQuery.add("d", GeoConverters.DistanceToStringConverter.INSTANCE.convert(new Distance(5)));

    List<EventDocument> result = template.execute(new SolrCallback<List<EventDocument>>() {

      @Override
      public List<EventDocument> doInSolr(SolrServer solrServer) throws SolrServerException, IOException {
        return template.getConverter().read(solrServer.query(solrQuery).getResults(), EventDocument.class);
      }
    });

A litte bit easier would be to provide required parameters for geodist().

    SimpleQuery query = new SimpleQuery(conditions);
    query.addProjectionOnField("*");
    query.addProjectionOnField("distance:geodist(store," + GeoConverters.GeoLocationToStringConverter.INSTANCE.convert(new GeoLocation(45.15, -93.85)) + ")");
    Page<EventDocument> result = template.queryForPage(query, EventDocument.class);

解决方法二

In order to retrieve distance you can add pt and sfield parameters to geodist().

SimpleQuery query = new SimpleQuery(conditions);
query.addProjectionOnField("*");
query.addProjectionOnField("distance:geodist(latlng," + GeoConverters.GeoLocationToStringConverter.INSTANCE.convert(new GeoLocation(34.13, -80.9)) + ")");
Page<EventDocument> result = template.queryForPage(query, YourDocument.class);

in your entity you’ll need

@Indexed(readonly=true)
Float distance;

Property has to be added to entity in order to allow passing value into it.

class SolrEntity {
  @Id
  private String id;
  
  //distance field not to be written when adding document to solr
  @Indexed(false)
  private Float distance;

Using DistanceField within query will make solr calculate distance.

Query q = new SimpleQuery("*:*");
q.addProjectionOnField(new DistanceField("distance", "store", new GeoLocation(45.15, -93.85)));
solrTemplate.queryForPage(q, SolrEntity.class);

解决方法三

For reference I managed to get this working after a variation on a solution posted here: How to return distance and score in spatial search using spring-data-solr

Because I’m using SOLR 4 type of location_rpt, the geodist() function didn’t support the type. So in the documentation they suggest an alternative of returning the distance using the score parameter. (note it’s returned as degrees and needs to be converted = if anyone knows how to do that conversion on SOLR then please post it here).

So I ended up using a simple String Criteria to add the score=distance phrase into the Geofilter expression.

Here’s my code to get the results of a geofilter, sorted by distance using the Spring Data SOLR API and location_rpt schema type.

@Override
    public SimpleSearchResults searchByRegion(SimpleSearchForm searchForm, RegionDocument region) {
        logger.entry();


        SimpleQuery query = new SimpleQuery();
        query.addProjectionOnField("*");
        query.addProjectionOnField("score");

        StringBuffer buf = new StringBuffer("");
        buf.append("{!geofilt pt=");
        buf.append(region.getLat());
        buf.append(",");
        buf.append(region.getLng());
        buf.append(" sfield=location d=");
        buf.append(5.0);
        buf.append(" score=distance}");

        query.addCriteria(new SimpleStringCriteria(buf.toString()));

        FilterQuery docType = new SimpleFilterQuery();
        docType.addCriteria(new Criteria("docType").is("LOCATION"));

        query.addFilterQuery(docType);

        query.addSort(new Sort(Sort.Direction.ASC, "score"));

        Page<LocationDocument> results = solrTemplate1.queryForPage(query, LocationDocument.class);


        SimpleSearchResults dto2 = new SimpleSearchResults();
        dto2.setSearchTerm(searchForm.getSearchTerm());

        if (results.getContent().isEmpty()) {
            logger.debug("results were empty.");
        } else {
            dto2.setPage(results);
        }

        logger.exit();

        return dto2;
    }

解决方法四

@Override
public Page<StructureDocument> 
findStructuresByNameAndCoordinates(String value, Point point, Pageable 
page){
SimpleQuery query = new SimpleQuery().setPageRequest(page);
query.addProjectionOnField("*");
query.addProjectionOnField("score");

StringBuffer buf = new StringBuffer("");
buf.append("{!geofilt pt=");
buf.append(point.getX());
buf.append(",");
buf.append(point.getY());
buf.append(" sfield=coordinates d=");
buf.append(2000.0);
buf.append(" score=distance}");

query.addCriteria(new SimpleStringCriteria(buf.toString()));

FilterQuery searchTerm = new SimpleFilterQuery();
searchTerm.addCriteria(new Criteria("name").contains(value));
query.addFilterQuery(searchTerm);

query.addSort(new Sort(Sort.Direction.ASC, "score"));

Moreover I added to my solr document “score” attribute, used to store distance value calculated by geodist function.

@Score
private Double score;

参考资料

1. 论坛里的解决方法
2. 官网问题追踪里的解决方法