feat(queries): add filter stations by line ID or Name

feat(queries): add filter stations by line ID or Name

README.md

@@ -8,18 +8,28 @@ It provides information about bus stops and lines, metro stations/lines, and pub
 
 ### Feature Roadmap / Checklist for v1.0.0
 
+#### Metro ✅
+
 - [x] `metroStation` query with information about one metro station (find by name or id)
 - [x] `metroStations` query with information about metro stations
 - [x] `metroLine` query with information about one metro line (find by name or id)
 - [x] `metroLines` query with information about metro lines
+- [x] Add filtering of the stations by line ID or name
+
+#### Bus
+
 - [ ] `busStops` query with information about bus stops
 - [ ] `busStop` query with information about one bus stop (find by name or id)
 - [ ] `busLines` query with information about bus lines
 - [ ] `busLine` query with information about a bus line (find by name or id)
+
+#### Bike
+
 - [ ] `bikeStations` query with information about bike stations
 - [ ] `bikeStation` query with information about one bike station (find by name or id)
 - [ ] Add bike availability information to the `bikeStations` query
-- [ ] Add filtering of the stations by line ID or name (cannot do it on BusStops)
+
+#### Tram
 
 ## GraphQL Playground 🚀
 

schema.graphql

@@ -4,7 +4,7 @@ schema {
 
 """Root Query"""
 type RootQuery {
-  metroStations(after: String, first: Int, before: String, last: Int): MetroStations
+  metroStations(after: String, first: Int, before: String, last: Int, filterBy: FilterByInput): MetroStations
   metroStation(findBy: FindByInput!): MetroStation
   metroLine(findBy: FindByInput!): MetroLine
   metroLines(after: String, first: Int, before: String, last: Int): MetroLines
@@ -74,6 +74,14 @@ type Coordinates {
   altitude: Float
 }
 
+"""
+Input for the filterBy argument of the queries, which allows filtering a connection by some parameters (e.g. lineName or lineId)
+"""
+input FilterByInput {
+  lineId: Int
+  lineName: String
+}
+
 """
 Input for the FindBy argument of the queries, which allows finding an entity by some parameters (e.g. name or id)
 """

src/datasources/MetroDataSource.ts

@@ -1,6 +1,7 @@
 import TmbApiDataSource from "./TmbApiDataSource";
 import type {
   FindByInput,
+  FilterByInput,
   MetroStation as MetroStationType,
   MetroLine as MetroLineType,
 } from "../../types";
@@ -167,7 +168,10 @@ export default class MetroDataSource extends TmbApiDataSource {
   async getLineStations({
     id,
     name,
-  }: FindByInput): Promise<MetroStationType[] | null> {
+  }: FindByInput): Promise<{
+    numberOfStations: number | null;
+    stations: MetroStationType[];
+  }> {
     const path = ["linies/metro", id, "estacions"].filter(Boolean).join("/");
     const nameFilterParameter = name ? { filter: `NOM_LINIA='${name}'` } : {};
 
@@ -177,7 +181,10 @@ export default class MetroDataSource extends TmbApiDataSource {
       response?.features?.map((station) => this.metroStationReducer(station)) ??
       [];
 
-    return stations;
+    return {
+      numberOfStations: response?.numberReturned ?? null,
+      stations,
+    };
   }
 
   async getLine({ id, name }: FindByInput): Promise<MetroLineType | null> {
@@ -209,7 +216,7 @@ export default class MetroDataSource extends TmbApiDataSource {
       return new ApolloError("The line object returned did not exist");
     }
 
-    const stations = await this.getLineStations({ id, name });
+    const { stations } = await this.getLineStations({ id, name });
 
     return {
       ...line,
@@ -232,7 +239,7 @@ export default class MetroDataSource extends TmbApiDataSource {
     const lines = await Promise.all(
       (response?.features ?? []).map(async (line: MetroLineAPIType) => {
         const reducedLine = this.metroLineReducer(line);
-        const stations = await this.getLineStations({
+        const { stations } = await this.getLineStations({
           id: reducedLine.id,
           name: reducedLine.name,
         });

src/datasources/__tests__/MetroDataSource.test.ts

@@ -15,9 +15,10 @@ describe("MetroDataSource", () => {
   const mockGet = jest.fn();
 
   MetroDataSource.get = mockGet;
-  MetroDataSource.getLineStations = jest
-    .fn()
-    .mockReturnValue(mockMetroLinesResponse.lines[0].stations);
+  MetroDataSource.getLineStations = jest.fn().mockReturnValue({
+    numberOfStations: 5,
+    stations: mockMetroLinesResponse.lines[0].stations,
+  });
 
   describe("[getAllLines]", () => {
     it("Correctly looks up the lines from the API", async () => {

src/inputs/FilterByInput.ts

@@ -0,0 +1,15 @@
+import { GraphQLInt, GraphQLInputObjectType, GraphQLString } from "graphql";
+
+export default new GraphQLInputObjectType({
+  name: "FilterByInput",
+  description:
+    "Input for the filterBy argument of the queries, which allows filtering a connection by some parameters (e.g. lineName or lineId)",
+  fields: {
+    lineId: {
+      type: GraphQLInt,
+    },
+    lineName: {
+      type: GraphQLString,
+    },
+  },
+});

src/queries/MetroStationsQuery.ts

@@ -1,14 +1,11 @@
-import {
-  connectionArgs,
-  ConnectionArguments,
-  connectionFromArray,
-} from "graphql-relay";
+import { connectionArgs, connectionFromArray } from "graphql-relay";
 import type {
   MetroStations as MetroStationsType,
   MetroStationConnection as MetroStationConnectionType,
 } from "../../types";
 import { MetroStationConnection } from "../outputs/MetroStation";
 import { GraphQLObjectType, GraphQLInt } from "graphql";
+import filterByInput from "../inputs/FilterByInput";
 
 const MetroStations = new GraphQLObjectType({
   name: "MetroStations",
@@ -27,16 +24,25 @@ const MetroStations = new GraphQLObjectType({
 
 export default {
   type: MetroStations,
-  args: connectionArgs,
-  resolve: async (
-    _,
-    args: ConnectionArguments,
-    { dataSources }
-  ): Promise<MetroStationsType> => {
-    const {
-      numberOfStations,
-      stations,
-    } = await dataSources.metro.getAllStations();
+  args: {
+    ...connectionArgs,
+    filterBy: {
+      type: filterByInput,
+    },
+  },
+  resolve: async (_, args, { dataSources }): Promise<MetroStationsType> => {
+    const { filterBy } = args;
+
+    const { numberOfStations, stations } = await (async () => {
+      //We get all the stations if no filter provided, if not we get the lines stations
+      if (!filterBy?.lineId && !filterBy?.lineName) {
+        return await dataSources.metro.getAllStations();
+      }
+      return await dataSources.metro.getLineStations({
+        id: filterBy?.lineId ?? null,
+        name: filterBy?.lineName ?? null,
+      });
+    })();
 
     return {
       numberOfStations,

types/index.d.ts

@@ -25,6 +25,7 @@ export type RootQueryMetroStationsArgs = {
   first?: Maybe<Scalars['Int']>;
   before?: Maybe<Scalars['String']>;
   last?: Maybe<Scalars['Int']>;
+  filterBy?: Maybe<FilterByInput>;
 };
 
 
@@ -109,6 +110,12 @@ export type Coordinates = {
   altitude?: Maybe<Scalars['Float']>;
 };
 
+/** Input for the filterBy argument of the queries, which allows filtering a connection by some parameters (e.g. lineName or lineId) */
+export type FilterByInput = {
+  lineId?: Maybe<Scalars['Int']>;
+  lineName?: Maybe<Scalars['String']>;
+};
+
 /** Input for the FindBy argument of the queries, which allows finding an entity by some parameters (e.g. name or id) */
 export type FindByInput = {
   id?: Maybe<Scalars['Int']>;