node.js - 如何使用mongoose在mongodb中使用纬度和经度查找附近的点

Question

架构:

const locationSchema = new mongoose.Schema({
    id:String,
    name:{type: String , required:true},
    address:String,
    rating:{type:Number , "default":0, min:0 , max:5 },
    facilities:[String],
    // geoJSON schema 1
    coords: 
    {
        type: {type: String},
        coordinates:[]

    },

    openingTimes: [openingTimeSchema],
    reviews: [reviewSchema]
    });

    locationSchema.index({'coords':'2dsphere'})

端点:http://localhost:3000/api/locations?lng=-0.7992599&lat=51.378091

const theEarth = (function() {
    console.log('theEarth');
    const earthRadius = 6371; // km, miles is 3959

    const getDistanceFromRads = function(rads) {
      return parseFloat(rads * earthRadius);
    };

    const getRadsFromDistance = function(distance) {
      return parseFloat(distance / earthRadius);
    };

    return {
      getDistanceFromRads: getDistanceFromRads,
      getRadsFromDistance: getRadsFromDistance
    };
  })();

module.exports.locationsListByDistance = (req,res) => {

    const longitude = parseFloat(req.query.lng);
    const latitude = parseFloat(req.query.lat);
    //const maxDistance = parseFloat(req.query.maxDistance);
     Loc.aggregate(
        [{
            $geoNear: {
                near: { type: "Point", coordinates: [ longitude , latitude ] },
                distanceField: "coords.calculated", // required
                maxDistance: theEarth.getRadsFromDistance(20),
                includeLocs: "coords.location",
                spherical:true


              }

            }
        ],function(err,results){
            console.log(results);
        });




    sendJsonResponse(res,200,results);

};

错误:

UnhandledPromiseRejectionWarning: MongoError: There is more than one 2dsphere index on Loc8r.locations; unsure which to use for $geoNear
    at MessageStream.messageHandler (E:\Udemy\NodeTutorial\getting-mean\loc8r\node_modules\mongodb\lib\cmap\connection.js:261:20)      
    at MessageStream.emit (events.js:198:13)
    at processIncomingData (E:\Udemy\NodeTutorial\getting-mean\loc8r\node_modules\mongodb\lib\cmap\message_stream.js:144:12)
    at MessageStream._write (E:\Udemy\NodeTutorial\getting-mean\loc8r\node_modules\mongodb\lib\cmap\message_stream.js:42:5)
    at doWrite (_stream_writable.js:415:12)
    at writeOrBuffer (_stream_writable.js:399:5)
    at MessageStream.Writable.write (_stream_writable.js:299:11)
    at Socket.ondata (_stream_readable.js:709:20)
    at Socket.emit (events.js:198:13)
    at addChunk (_stream_readable.js:288:12)
    at readableAddChunk (_stream_readable.js:269:11)
    at Socket.Readable.push (_stream_readable.js:224:10)
    at TCP.onStreamRead [as onread] (internal/stream_base_commons.js:94:17)
(node:5040) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async 
function without a catch block, or by rejecting a promise which was not handled with .catch(). (rejection id: 2)
GET /bootstrap/bootstrap.min.css 304 0.954 ms - -
GET /stylesheets/style.css 304 5.782 ms - -
GET /api/bootstrap/jquery.min.js 404 65.965 ms - 3123
GET /api/bootstrap/bootstrap.min.js 404 116.055 ms - 3123

我正在使用上述方法来查找距离接近端点中查询参数中的经度和纬度的文档，但结果返回未定义，请告诉我如何更正此错误。

Answer 1

module.exports.locationsListByDistance = (req,res) => {

        const longitude = parseFloat(req.query.lng);
        const latitude = parseFloat(req.query.lat);
        //const maxDistance = parseFloat(req.query.maxDistance);
       // const options = {near :[longitude,latitude],maxDistance:10000}
        Loc.find({

          coords: {
            $near : {


              $maxDistance: 10,
              $geometry : {
                type : 'Point',
                coordinates:[longitude,latitude]
              }
            }
          }
        }).find((error,results)=>{
          if (error) console.log(error);
        //console.log(JSON.stringify(results, 0, 2));
        sendJsonResponse(res,200,results);
        });

       };

这工作正常。