bulk areas query

Author: vnugent

src/db/AreaTypes.ts

@@ -259,3 +259,7 @@ export enum OperationType {
   /** Set areas' sorting index */
   orderAreas = 'orderArea'
 }
+
+export interface BulkAreasGQLQueryInput {
+  ancestors: string[]
+}

src/graphql/area/AreaQueries.ts

@@ -1,4 +1,4 @@
-import { AreaType } from '../../db/AreaTypes'
+import { AreaType, BulkAreasGQLQueryInput } from '../../db/AreaTypes'
 import { GQLContext } from '../../types'
 
 const AreaQueries = {
@@ -11,8 +11,13 @@ const AreaQueries = {
   countries: async (_, params, { dataSources }: GQLContext): Promise<AreaType[]> => {
     const { areas } = dataSources
     return await areas.listAllCountries()
-  }
+  },
 
+  bulkAreas: async (_: any, params, { dataSources }: GQLContext): Promise<AreaType[]> => {
+    const { areas } = dataSources
+    const { ancestors } = params as BulkAreasGQLQueryInput
+    return await areas.bulkDownloadAreas(ancestors)
+  }
 }
 
 export default AreaQueries

src/graphql/schema/Area.gql

@@ -1,6 +1,13 @@
 type Query {
   area(uuid: ID): Area
   areas(filter: Filter, sort: Sort): [Area]
+
+  """
+  Bulk download an area and its children starting from ancestors paths (inclusive).
+  To keep payload at a reasonable size ancestors must have at least 2 elements.
+  """
+  bulkAreas(ancestors: [String!]!): [Area]
+
   stats: Stats
   cragsNear(
     placeId: String

src/model/AreaDataSource.ts

@@ -1,3 +1,5 @@
+import { GraphQLError } from 'graphql'
+import { ApolloServerErrorCode } from '@apollo/server/errors'
 import { MongoDataSource } from 'apollo-datasource-mongodb'
 import { Filter } from 'mongodb'
 import muuid from 'uuid-mongodb'
@@ -275,4 +277,16 @@ export default class AreaDataSource extends MongoDataSource<AreaType> {
     }
     return await this.areaModel.find(filter).lean()
   }
+
+  async bulkDownloadAreas (ancestors: string[]): Promise<AreaType[]> {
+    if (ancestors.length < 2) {
+      throw new GraphQLError('Must provide at least 2 ancestors.', {
+        extensions: {
+          code: ApolloServerErrorCode.BAD_USER_INPUT
+        }
+      })
+    }
+    const ancestorsCSV = ancestors.join(',')
+    return await this.findDescendantsByPath(ancestorsCSV)
+  }
 }