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monolith/index.js

@@ -1,5 +1,6 @@
 const { ApolloServer } = require("@apollo/server");
 const { startStandaloneServer } = require("@apollo/server/standalone");
+const { buildSubgraphSchema } = require("@apollo/subgraph");
 
 const { readFileSync } = require("fs");
 const axios = require("axios");
@@ -18,11 +19,13 @@ const PaymentsAPI = require("./datasources/payments");
 
 async function startApolloServer() {
   const server = new ApolloServer({
-    typeDefs,
-    resolvers,
+    schema: buildSubgraphSchema({
+      typeDefs,
+      resolvers,
+    }),
   });
 
-  const port = 4000;
+  const port = 4001;
 
   try {
     const { url } = await startStandaloneServer(server, {

monolith/package.json

@@ -23,6 +23,7 @@
   "dependencies": {
     "@apollo/datasource-rest": "^4.3.2",
     "@apollo/server": "^4.0.1",
+    "@apollo/subgraph": "^2.8.0",
     "axios": "^1.6.2",
     "concurrently": "^6.3.0",
     "date-fns": "^2.25.0",

monolith/resolvers.js

@@ -381,8 +381,8 @@ const resolvers = {
     },
   },
   Listing: {
-    host: ({ hostId }, _, { dataSources }) => {
-      return dataSources.accountsAPI.getUser(hostId);
+    host: ({ hostId }) => {
+      return { id: hostId };
     },
     overallRating: ({ id }, _, { dataSources }) => {
       return dataSources.reviewsDb.getOverallRatingForListing(id);
@@ -425,8 +425,8 @@ const resolvers = {
     checkOutDate: ({ checkOutDate }, _, { dataSources }) => {
       return dataSources.bookingsDb.getHumanReadableDate(checkOutDate);
     },
-    guest: ({ guestId }, _, { dataSources }) => {
-      return dataSources.accountsAPI.getUser(guestId);
+    guest: ({ guestId }) => {
+      return { id: guestId };
     },
     totalPrice: async (
       { listingId, checkInDate, checkOutDate },
@@ -451,8 +451,14 @@ const resolvers = {
     },
   },
   Review: {
-    author: ({ authorId }, _, { dataSources }) => {
-      return dataSources.accountsAPI.getUser(authorId);
+    author: (review) => {
+      let role = "";
+      if (review.targetType === "LISTING" || review.targetType === "HOST") {
+        role = "Guest";
+      } else {
+        role = "Host";
+      }
+      return { __typename: role, id: review.authorId, role };
     },
   },
   AmenityCategory: {

monolith/schema.graphql

@@ -1,3 +1,6 @@
+extend schema
+  @link(url: "https://specs.apollo.dev/federation/v2.7", import: ["@key"])
+
 type Query {
   ### User accounts
   user(id: ID!): User
@@ -38,7 +41,10 @@ type Mutation {
   "Creates a new listing for the currently authenticated host"
   createListing(listing: CreateListingInput!): CreateListingResponse!
   "Updates an existing listing"
-  updateListing(listingId: ID!, listing: UpdateListingInput!): UpdateListingResponse!
+  updateListing(
+    listingId: ID!
+    listing: UpdateListingInput!
+  ): UpdateListingResponse!
 
   ### Bookings
   createBooking(createBookingInput: CreateBookingInput): CreateBookingResponse!
@@ -51,7 +57,10 @@ type Mutation {
     locationReview: ReviewInput!
   ): SubmitHostAndLocationReviewsResponse!
   "Creates a review for the guest - must be authored by host of past booking"
-  submitGuestReview(bookingId: ID!, guestReview: ReviewInput!): SubmitGuestReviewResponse!
+  submitGuestReview(
+    bookingId: ID!
+    guestReview: ReviewInput!
+  ): SubmitGuestReviewResponse!
 
   ### Wallet
   addFundsToWallet(amount: Float!): AddFundsToWalletResponse!
@@ -78,7 +87,7 @@ interface User {
 }
 
 "A host is a type of Airlock user. They own listings."
-type Host implements User {
+type Host implements User @key(fields: "id") {
   id: ID!
   "The user's first and last name"
   name: String!
@@ -91,7 +100,7 @@ type Host implements User {
 }
 
 "A guest is a type of Airlock user. They book places to stay."
-type Guest implements User {
+type Guest implements User @key(fields: "id") {
   id: ID!
   "The user's first and last name"
   name: String!
@@ -126,7 +135,7 @@ type UpdateProfileResponse implements MutationResponse {
 ### Listings
 
 "A listing is a location owned by a host. A listing has a list of amenities it offers. Listings have a fixed cost per night value."
-type Listing {
+type Listing @key(fields: "id") {
   id: ID!
   "The listing's title"
   title: String!
@@ -273,7 +282,7 @@ type UpdateListingResponse implements MutationResponse {
 ### Bookings
 
 "A booking is a reservation for a specific listing"
-type Booking {
+type Booking @key(fields: "id") {
   id: ID!
   "The listing associated with the reservation"
   listing: Listing!
@@ -334,7 +343,7 @@ type CreateBookingResponse implements MutationResponse {
 ### Reviews
 
 "A review consists of a numerical rating and written text. It can be written by a host or a guest."
-type Review {
+type Review @key(fields: "id") {
   id: ID!
   "Written comment the author has written about the review target"
   text: String!

router/router-config.yaml

@@ -1,2 +1,11 @@
 include_subgraph_errors:
-  all: true # Propagate errors from all subgraphs
+  all: true # Propagate errors from all subgraphs
+headers:
+  all:
+    request:
+      - propagate:
+          named: "Authorization"
+cors:
+  origins:
+    - http://localhost:3000 # Allows any locally-running client to run against your Router
+    - https://studio.apollographql.com # Allows Apollo Studio to still run queries against your Router

subgraph-accounts/datasources/accounts.js

@@ -0,0 +1,19 @@
+const { RESTDataSource } = require("@apollo/datasource-rest");
+
+class AccountsAPI extends RESTDataSource {
+  baseURL = "http://localhost:4011/";
+
+  login(username) {
+    return this.get(`login/${username}`);
+  }
+
+  updateUser({ userId, userInfo }) {
+    return this.patch(`user/${userId}`, { body: { ...userInfo } });
+  }
+
+  getUser(userId) {
+    return this.get(`user/${userId}`);
+  }
+}
+
+module.exports = AccountsAPI;

subgraph-accounts/datasources/datasource.js

@@ -0,0 +1 @@
+// TODO: rename file and add datasource code here