docs(examples): add examples for generic types

dev.js

@@ -3,6 +3,7 @@ require("ts-node/register/transpile-only");
 // require("./examples/authorization/index.ts");
 // require("./examples/automatic-validation/index.ts");
 // require("./examples/enums-and-unions/index.ts");
+// require("./examples/generic-types/index.ts");
 // require("./examples/interfaces-inheritance/index.ts");
 // require("./examples/middlewares/index.ts");
 // require("./examples/redis-subscriptions/index.ts");

docs/examples.md

@@ -12,10 +12,11 @@ All examples has a `examples.gql` file with sample queries/mutations/subscriptio
 
 ## Advanced
 - [Enums and unions](https://github.com/19majkel94/type-graphql/tree/master/examples/enums-and-unions)
-- [Interfaces and types inheritance](https://github.com/19majkel94/type-graphql/tree/master/examples/interfaces-inheritance)
 - [Subscriptions (simple)](https://github.com/19majkel94/type-graphql/tree/master/examples/simple-subscriptions)
 - [Subscriptions (using Redis)](https://github.com/19majkel94/type-graphql/tree/master/examples/redis-subscriptions)
+- [Interfaces and types inheritance](https://github.com/19majkel94/type-graphql/tree/master/examples/interfaces-inheritance)
 - [Resolvers inheritance](https://github.com/19majkel94/type-graphql/tree/master/examples/resolvers-inheritance)
+- [Generic types](https://github.com/19majkel94/type-graphql/tree/master/examples/generic-types)
 
 ## Features usage
 - [Dependency injection (IoC container)](https://github.com/19majkel94/type-graphql/tree/master/examples/using-container)

examples/README.md

@@ -8,10 +8,11 @@ All examples has a `examples.gql` file with sample queries/mutations/subscriptio
 
 ## Advanced
 - [Enums and unions](./enums-and-unions)
-- [Interfaces and types inheritance](./interfaces-inheritance)
 - [Subscriptions (simple)](./simple-subscriptions)
 - [Subscriptions (using Redis)](./redis-subscriptions)
+- [Interfaces and types inheritance](./interfaces-inheritance)
 - [Resolvers inheritance](./resolvers-inheritance)
+- [Generic types](./generic-types)
 
 ## Features usage
 - [Dependency injection (IoC container)](./using-container)

examples/generic-types/examples.gql

@@ -0,0 +1,16 @@
+query GetRecipes {
+  recipes(first: 3) {
+    items {
+      title
+      ratings
+    }
+    total
+    hasMore
+  }
+}
+
+mutation AddRecipe {
+  addSampleRecipe {
+    title
+  }
+}

examples/generic-types/index.ts

@@ -0,0 +1,23 @@
+import "reflect-metadata";
+import { ApolloServer } from "apollo-server";
+import * as path from "path";
+import { buildSchema } from "../../src";
+
+import RecipeResolver from "./recipe.resolver";
+
+async function bootstrap() {
+  const schema = await buildSchema({
+    resolvers: [RecipeResolver],
+    emitSchemaFile: path.resolve(__dirname, "schema.gql"),
+  });
+
+  const server = new ApolloServer({
+    schema,
+    playground: true,
+  });
+
+  const { url } = await server.listen(4000);
+  console.log(`Server is running, GraphQL Playground available at ${url}`);
+}
+
+bootstrap().catch(console.error);

examples/generic-types/paginated-response.type.ts

@@ -0,0 +1,17 @@
+import { ClassType, Field, ObjectType, Int } from "../../src";
+
+export default function PaginatedResponse<TItem>(TItemClass: ClassType<TItem>) {
+  // `isAbstract` decorator option is mandatory to prevent registering in schema
+  @ObjectType({ isAbstract: true })
+  abstract class PaginatedResponseClass {
+    @Field(type => [TItemClass])
+    items: TItem[];
+
+    @Field(type => Int)
+    total: number;
+
+    @Field()
+    hasMore: boolean;
+  }
+  return PaginatedResponseClass;
+}

examples/generic-types/recipe.resolver.ts

@@ -0,0 +1,45 @@
+import { ObjectType, Query, Mutation, Arg, Int, Resolver } from "../../src";
+
+import PaginatedResponse from "./paginated-response.type";
+import Recipe from "./recipe.type";
+import createSampleRecipes from "./recipe.samples";
+
+// we need to create a temporary class for the abstract, generic class "instance"
+@ObjectType()
+class RecipesResponse extends PaginatedResponse(Recipe) {
+  // simple helper for creating new instances easily
+  constructor(recipesResponse: RecipesResponse) {
+    super();
+    Object.assign(this, recipesResponse);
+  }
+
+  // you can add more fields here if you need
+}
+
+@Resolver()
+export default class RecipeResolver {
+  private readonly recipes = createSampleRecipes();
+
+  @Query({ name: "recipes" })
+  getRecipes(
+    @Arg("first", type => Int, { nullable: true, defaultValue: 10 }) first: number,
+  ): RecipesResponse {
+    const total = this.recipes.length;
+    return new RecipesResponse({
+      items: this.recipes.slice(0, first),
+      hasMore: total > first,
+      total,
+    });
+  }
+
+  @Mutation()
+  addSampleRecipe(): Recipe {
+    const recipe: Recipe = {
+      title: "Sample recipe",
+      description: "Sample description",
+      ratings: [1, 2, 3, 4],
+    };
+    this.recipes.push(recipe);
+    return recipe;
+  }
+}

examples/generic-types/recipe.samples.ts

@@ -0,0 +1,21 @@
+import Recipe from "./recipe.type";
+
+export default function createSampleRecipes(): Recipe[] {
+  return [
+    {
+      description: "Desc 1",
+      title: "Recipe 1",
+      ratings: [0, 3, 1],
+    },
+    {
+      description: "Desc 2",
+      title: "Recipe 2",
+      ratings: [4, 2, 3, 1],
+    },
+    {
+      description: "Desc 3",
+      title: "Recipe 3",
+      ratings: [5, 4],
+    },
+  ];
+}

examples/generic-types/recipe.type.ts

@@ -0,0 +1,13 @@
+import { Field, ObjectType, Int } from "../../src";
+
+@ObjectType()
+export default class Recipe {
+  @Field()
+  title: string;
+
+  @Field()
+  description?: string;
+
+  @Field(type => [Int])
+  ratings: number[];
+}

examples/generic-types/schema.gql

@@ -0,0 +1,24 @@
+# -----------------------------------------------
+# !!! THIS FILE WAS GENERATED BY TYPE-GRAPHQL !!!
+# !!!   DO NOT MODIFY THIS FILE BY YOURSELF   !!!
+# -----------------------------------------------
+
+type Mutation {
+  addSampleRecipe: Recipe!
+}
+
+type Query {
+  recipes(first: Int = 10): RecipesResponse!
+}
+
+type Recipe {
+  title: String!
+  description: String!
+  ratings: [Int!]!
+}
+
+type RecipesResponse {
+  items: [Recipe!]!
+  total: Int!
+  hasMore: Boolean!
+}