Update the nestjs implementation for new @requires / @key tests (#228)

Covers the changes outlined in #166.

Fixes #192

Author: hwillson

implementations/nestjs/products.graphql

@@ -1,23 +1,54 @@
 extend schema
-  @link(url: "https://specs.apollo.dev/federation/v2.0",
-        import: ["@key", "@shareable", "@provides", "@external", "@tag", "@extends", "@override", "@inaccessible"])
+  @link(
+    url: "https://specs.apollo.dev/federation/v2.0",
+    import: [
+      "@extends",
+      "@external",
+      "@key",
+      "@inaccessible",
+      "@override",
+      "@provides",
+      "@requires",
+      "@shareable",
+      "@tag"
+    ]
+  )
 
-directive @override(from: String!) on FIELD_DEFINITION
+type Product
+  @key(fields: "id")
+  @key(fields: "sku package")
+  @key(fields: "sku variation { id }") {
+    id: ID!
+    sku: String
+    package: String
+    variation: ProductVariation
+    dimensions: ProductDimension
+    createdBy: User @provides(fields: "totalProductsCreated")
+    notes: String @tag(name: "internal")
+    research: [ProductResearch!]!
+}
 
-type Product @key(fields: "id") @key(fields: "sku package") @key(fields: "sku variation { id }") {
-  id: ID!
-  sku: String
-  package: String
-  variation: ProductVariation
-  dimensions: ProductDimension
-  createdBy: User @provides(fields: "totalProductsCreated")
-  notes: String @tag(name: "internal")
+type DeprecatedProduct @key(fields: "sku package") {
+  sku: String!
+  package: String!
+  reason: String
+  createdBy: User
 }
 
 type ProductVariation {
   id: ID!
 }
 
+type ProductResearch @key(fields: "study { caseNumber }") {
+  study: CaseStudy!
+  outcome: String
+}
+
+type CaseStudy {
+  caseNumber: ID!
+  description: String
+}
+
 type ProductDimension @shareable {
   size: String
   weight: Float
@@ -26,10 +57,13 @@ type ProductDimension @shareable {
 
 extend type Query {
   product(id: ID!): Product
+  deprecatedProduct(sku: String!, package: String!): DeprecatedProduct @deprecated(reason: "Use product query instead")
 }
 
 extend type User @key(fields: "email") {
+  averageProductsCreatedPerYear: Int @requires(fields: "totalProductsCreated yearsOfEmployment")
   email: ID! @external
-  name: String @shareable @override(from: "users")
+  name: String @override(from: "users")
   totalProductsCreated: Int @external
+  yearsOfEmployment: Int! @external
 }

implementations/nestjs/src/app.module.ts

@@ -7,6 +7,8 @@ import {
 
 import { UsersResolver } from "./users.resolver";
 import { ProductsResolver } from "./products.resolver";
+import { ProductResearchResolver } from "./product-research.resolver";
+import { DeprecatedProductsResolver } from "./deprecated-products.resolver";
 
 @Module({
   imports: [
@@ -16,6 +18,11 @@ import { ProductsResolver } from "./products.resolver";
       path: "/",
     }),
   ],
-  providers: [UsersResolver, ProductsResolver],
+  providers: [
+    UsersResolver,
+    ProductsResolver,
+    ProductResearchResolver,
+    DeprecatedProductsResolver,
+  ],
 })
 export class AppModule {}

implementations/nestjs/src/deprecated-products.resolver.ts

@@ -0,0 +1,65 @@
+import {
+  Args,
+  Query,
+  Resolver,
+  ResolveField,
+  ResolveReference,
+} from "@nestjs/graphql";
+
+interface User {
+  email: string;
+  name: string;
+  totalProductsCreated: number;
+}
+
+interface DeprecatedProduct {
+  sku: string;
+  package: string;
+  reason: string;
+  createdBy: User;
+}
+
+const user = {
+  email: "[email protected]",
+  name: "Jane Smith",
+  totalProductsCreated: 1337,
+};
+
+const deprecatedProduct = {
+  sku: "apollo-federation-v1",
+  package: "@apollo/federation-v1",
+  reason: "Migrate to Federation V2",
+};
+
+@Resolver("DeprecatedProduct")
+export class DeprecatedProductsResolver {
+  constructor() {}
+
+  @Query()
+  deprecatedProduct(
+    @Args("sku") sku: string,
+    @Args("package") packageName: string,
+  ) {
+    return sku === deprecatedProduct.sku &&
+      packageName === deprecatedProduct.package
+      ? deprecatedProduct
+      : null;
+  }
+
+  @ResolveField("createdBy")
+  getCreatedBy() {
+    return user;
+  }
+
+  @ResolveReference()
+  resolveReference(reference: DeprecatedProduct) {
+    if (
+      reference.sku === deprecatedProduct.sku &&
+      reference.package === deprecatedProduct.package
+    ) {
+      return deprecatedProduct;
+    } else {
+      return null;
+    }
+  }
+}

implementations/nestjs/src/product-research.resolver.ts

@@ -0,0 +1,43 @@
+import { Resolver, ResolveField, ResolveReference } from "@nestjs/graphql";
+
+interface CaseStudy {
+  caseNumber: string;
+  description: string;
+}
+
+interface ProductResearch {
+  study: CaseStudy;
+  outcome: string;
+}
+
+const productResearch = [
+  {
+    study: {
+      caseNumber: "1234",
+      description: "Federation Study",
+    },
+  },
+  {
+    study: {
+      caseNumber: "1235",
+      description: "Studio Study",
+    },
+  },
+];
+
+@Resolver("ProductResearch")
+export class ProductResearchResolver {
+  constructor() {}
+
+  @ResolveField()
+  getStudy() {
+    return productResearch[0].study;
+  }
+
+  @ResolveReference()
+  resolveReference(reference: ProductResearch) {
+    return productResearch.find(
+      (p) => reference.study.caseNumber === p.study.caseNumber,
+    );
+  }
+}

implementations/nestjs/src/users.resolver.ts

@@ -8,4 +8,14 @@ export class UsersResolver {
   getName() {
     return "Jane Smith";
   }
+
+  @ResolveField("averageProductsCreatedPerYear")
+  getAverageProductsCreatedPerYear({
+    totalProductsCreated,
+    yearsOfEmployment,
+  }) {
+    return totalProductsCreated
+      ? Math.round(totalProductsCreated / yearsOfEmployment)
+      : null;
+  }
 }