Redis 地理位置搜索入门

import * as StoreInventoryRepo from '../../../common/models/store-inventory-repo';

interface IInventoryBodyFilter {
  productDisplayName?: string;

  searchRadiusInMiles?: number;
  userLocation?: {
    latitude?: number;
    longitude?: number;
  },
}

const searchStoreInventoryByGeoFilter = async (
  _inventoryFilter: IInventoryBodyFilter,
) => {
  // (1) ---
  const redisClient = getNodeRedisClient();
  const repository = StoreInventoryRepo.getRepository();
  let storeProducts: IStoreInventory[] = [];
  const trimmedStoreProducts: IStoreInventory[] = [] // similar item of other stores are removed
  const uniqueProductIds = {};

  if (repository
    && _inventoryFilter?.userLocation?.latitude
    && _inventoryFilter?.userLocation?.longitude) {

    const lat = _inventoryFilter.userLocation.latitude;
    const long = _inventoryFilter.userLocation.longitude;
    const radiusInMiles = _inventoryFilter.searchRadiusInMiles || 500;

    // (2) --- Query Construction
    let queryBuilder = repository
      .search()
      .and('statusCode')
      .eq(1)
      .and('stockQty')
      .gt(0)
      .and('storeLocation')
      .inRadius((circle) => {
        return circle
          .latitude(lat)
          .longitude(long)
          .radius(radiusInMiles)
          .miles
      });

    if (_inventoryFilter.productDisplayName) {
      queryBuilder = queryBuilder
        .and('productDisplayName')
        .matches(_inventoryFilter.productDisplayName)
    }

    console.log(queryBuilder.query);

    /* Sample queryBuilder.query to run on CLI
    FT.SEARCH "storeInventory:storeInventoryId:index" "( ( ( (@statusCode:[1 1]) (@stockQty:[(0 +inf]) ) (@storeLocation:[-73.968285 40.785091 50 mi]) ) (@productDisplayName:'puma') )"
            */

   // (3) --- Executing the Query
    const indexName = `storeInventory:storeInventoryId:index`;
    const aggregator = await redisClient.ft.aggregate(
      indexName,
      queryBuilder.query,
      {
        LOAD: ["@storeId", "@storeName", "@storeLocation", "@productId", "@productDisplayName", "@stockQty"],
        STEPS: [{
          type: AggregateSteps.APPLY,
          expression: `geodistance(@storeLocation, ${long}, ${lat})/1609`,
          AS: 'distInMiles'
        }, {
          type: AggregateSteps.SORTBY,
          BY: ["@distInMiles", "@productId"]
        }, {
          type: AggregateSteps.LIMIT,
          from: 0,
          size: 1000,
        }]
      });

    /* Sample command to run on CLI
        FT.AGGREGATE "storeInventory:storeInventoryId:index"
          "( ( ( (@statusCode:[1 1]) (@stockQty:[(0 +inf]) ) (@storeLocation:[-73.968285 40.785091 50 mi]) ) (@productDisplayName:'puma') )"
          "LOAD" "6" "@storeId" "@storeName" "@storeLocation" "@productId" "@productDisplayName" "@stockQty"
          "APPLY" "geodistance(@storeLocation, -73.968285, 40.785091)/1609"
          "AS" "distInMiles"
          "SORTBY" "1" "@distInMiles"
          "LIMIT" "0" "100"
    */

    storeProducts = <IStoreInventory[]>aggregator.results;

    if (!storeProducts.length) {
      // throw `Product not found with in ${radiusInMiles}mi range!`;
    }
    else {

     // (4) --- Result Processing
      storeProducts.forEach((storeProduct) => {
        if (storeProduct?.productId && !uniqueProductIds[storeProduct.productId]) {
          uniqueProductIds[storeProduct.productId] = true;

          if (typeof storeProduct.storeLocation == "string") {
            const location = storeProduct.storeLocation.split(",");
            storeProduct.storeLocation = {
              longitude: Number(location[0]),
              latitude: Number(location[1]),
            }
          }

          trimmedStoreProducts.push(storeProduct)
        }
      });
    }
  }
  else {
    throw "Mandatory fields like userLocation latitude / longitude missing !"
  }

  return {
    storeProducts: trimmedStoreProducts,
    productIds: Object.keys(uniqueProductIds)
  };
};