chore: infinite query for products list (#9)

* chore: infinite query for products list

* chore: manually removing useless infinite queries

* chore: fixing display issue when navigating from orders

* chore: we should stop sending calls when there is no more data

.eslintignore

@@ -1,3 +1,4 @@
+libs/graphql/types/src/api.ts
 libs/graphql/types/src/index.ts
 apps/front/.next
 .dockerignore

.eslintrc.front.json

@@ -1,9 +1,10 @@
 {
-  "plugins": ["jest-dom"],
+  "plugins": ["jest-dom", "@tanstack/query"],
   "extends": [
     "./.eslintrc.json",
     "plugin:react/recommended",
-    "plugin:jest-dom/recommended"
+    "plugin:jest-dom/recommended",
+    "plugin:@tanstack/eslint-plugin-query/recommended"
   ],
   "env": { "jest": true },
   "settings": { "react": { "version": "detect" } },

apps/api/src/graphql/schema.graphql

@@ -60,6 +60,12 @@ type GqlCategory {
   products: [GqlProduct!]!
 }
 
+type GqlPaginatedProducts {
+  id: Int!
+  data: [GqlProduct!]!
+  hasMoreData: Boolean!
+}
+
 type GqlOrderedItem {
   id: ID!
   quantity: Int!
@@ -101,6 +107,7 @@ type GqlUserOrder {
 
 type Query {
   products: [GqlProduct!]!
+  productsByPage(pagination: GqlPaginationArgs!): GqlPaginatedProducts!
   productsWithIds(ids: [Int!]!): [GqlProduct!]!
   product(id: Int!): GqlProduct!
   categories: [GqlCategory!]!
@@ -111,6 +118,11 @@ type Query {
   myAddresses: [GqlAddress!]!
 }
 
+input GqlPaginationArgs {
+  offset: Int = 0
+  limit: Int = 25
+}
+
 type Mutation {
   signup(email: String!, lastName: String!, firstName: String!, password: String!): GqlAuthOutput!
   login(username: String!, password: String!): GqlAuthOutput!

apps/api/src/modules/dtos/pagination-args.dto.ts

@@ -0,0 +1,10 @@
+import { Field, InputType, Int } from '@nestjs/graphql';
+
+@InputType()
+export class GqlPaginationArgs {
+  @Field(() => Int)
+  offset = 0;
+
+  @Field(() => Int)
+  limit = 25;
+}

apps/api/src/modules/products/closures/get-paginated.closure.ts

@@ -0,0 +1,29 @@
+import { Injectable } from '@nestjs/common';
+
+import { DatabaseService, selectProduct } from '@backend/database';
+
+import { GqlPaginationArgs } from '../../dtos/pagination-args.dto';
+import { GetAllSelectType } from './get-all.closure';
+
+@Injectable()
+export class GetPaginatedClosure {
+  public static Include = selectProduct({
+    Category: true,
+  });
+
+  constructor(private readonly db: DatabaseService) {}
+
+  async fetch({
+    limit,
+    offset,
+  }: GqlPaginationArgs): Promise<[GetAllSelectType[], number]> {
+    return this.db.$transaction([
+      this.db.product.findMany({
+        include: GetPaginatedClosure.Include,
+        skip: offset,
+        take: limit,
+      }),
+      this.db.product.count(),
+    ]);
+  }
+}

apps/api/src/modules/products/dtos/gql.paginated-products.dto.ts

@@ -0,0 +1,16 @@
+import 'reflect-metadata';
+import { ObjectType, Field, Int } from '@nestjs/graphql';
+
+import { GqlProduct } from './gql.product.dto';
+
+@ObjectType()
+export class GqlPaginatedProducts {
+  @Field(() => Int)
+  id: number;
+
+  @Field(() => [GqlProduct])
+  data: Array<GqlProduct>;
+
+  @Field(() => Boolean)
+  hasMoreData: boolean;
+}

apps/api/src/modules/products/products.module.ts

@@ -5,12 +5,19 @@ import { DatabaseModule } from '@backend/database';
 import { CategoriesModule } from '../categories/categories.module';
 import { GetAllClosure } from './closures/get-all.closure';
 import { GetByClosure } from './closures/get-by.closure';
+import { GetPaginatedClosure } from './closures/get-paginated.closure';
 import { ProductsResolver } from './products.resolver';
 import { ProductsService } from './products.service';
 
 @Module({
   imports: [DatabaseModule, forwardRef(() => CategoriesModule)],
-  providers: [ProductsService, ProductsResolver, GetByClosure, GetAllClosure],
+  providers: [
+    ProductsService,
+    ProductsResolver,
+    GetByClosure,
+    GetAllClosure,
+    GetPaginatedClosure,
+  ],
   exports: [ProductsService, ProductsResolver],
 })
 export class ProductsModule {}

apps/api/src/modules/products/products.resolver.ts

@@ -10,8 +10,11 @@ import { Product, Category } from '@prisma/client';
 
 import { CategoriesService } from '../categories/categories.service';
 import { GqlCategory } from '../categories/dtos/gql.category.dto';
+import { GqlPaginationArgs } from '../dtos/pagination-args.dto';
 import { GqlProduct } from '../products/dtos/gql.product.dto';
 import { ProductsService } from '../products/products.service';
+import { GetAllSelectType } from './closures/get-all.closure';
+import { GqlPaginatedProducts } from './dtos/gql.paginated-products.dto';
 
 @Resolver(GqlProduct)
 export class ProductsResolver {
@@ -21,10 +24,18 @@ export class ProductsResolver {
   ) {}
 
   @Query(() => [GqlProduct], { name: 'products' })
-  async getAll(): Promise<Array<Product>> {
+  async getAll(): Promise<Array<GetAllSelectType>> {
     return this.products.getAll();
   }
 
+  @Query(() => GqlPaginatedProducts, { name: 'productsByPage' })
+  async getPaginatedProducts(
+    @Args({ name: 'pagination', type: () => GqlPaginationArgs })
+    pagination: GqlPaginationArgs
+  ): Promise<GqlPaginatedProducts> {
+    return this.products.getPaginated(pagination);
+  }
+
   @Query(() => [GqlProduct], { name: 'productsWithIds' })
   async getProductsWithIds(
     @Args('ids', { type: () => [Int] }) ids: Array<number>

apps/api/src/modules/products/products.service.ts

@@ -3,21 +3,39 @@ import { Product } from '@prisma/client';
 
 import { DatabaseService } from '@backend/database';
 
+import { GqlPaginationArgs } from '../dtos/pagination-args.dto';
 import { GetAllClosure, GetAllSelectType } from './closures/get-all.closure';
 import { GetByClosure, GetBySelectType } from './closures/get-by.closure';
+import { GetPaginatedClosure } from './closures/get-paginated.closure';
+import { GqlPaginatedProducts } from './dtos/gql.paginated-products.dto';
 
 @Injectable()
 export class ProductsService {
   constructor(
     private readonly db: DatabaseService,
     private readonly getAllClosure: GetAllClosure,
+    private readonly getPaginatedClosure: GetPaginatedClosure,
     private readonly getByClosure: GetByClosure
   ) {}
 
   async getAll(): Promise<Array<GetAllSelectType>> {
     return this.getAllClosure.fetch();
   }
 
+  async getPaginated(input: GqlPaginationArgs): Promise<GqlPaginatedProducts> {
+    const [data, count] = await this.getPaginatedClosure.fetch(input);
+
+    return {
+      id: data.length > 0 ? data.at(0).id : null,
+      data: data.map((product) => {
+        const { price, ...data } = product;
+
+        return { ...data, price: Number(price) };
+      }),
+      hasMoreData: data.length + input.offset < count,
+    };
+  }
+
   async getByIds(ids: Array<number>): Promise<Array<Product>> {
     return this.db.product.findMany({
       where: {

apps/front/src/components/specialized/shop/Shop.tsx

@@ -1,4 +1,4 @@
-import { useProductsQuery } from '@front/api';
+import { useInfiniteProductsByPageQuery } from '@front/api';
 import ErrorCircle from '@front/assets/icons/error-circle.svg';
 import {
   PageTitle,
@@ -9,7 +9,17 @@ import {
 import { ArticlesList } from './articles-list/ArticlesList';
 
 export const ShopRoot = () => {
-  const { status, data } = useProductsQuery();
+  const { status, data, fetchNextPage, hasNextPage, isFetchingNextPage } =
+    useInfiniteProductsByPageQuery(
+      {
+        offset: 0,
+        limit: 20,
+      },
+      {
+        getNextPageParam: (lastPage) =>
+          lastPage.productsByPage.hasMoreData === true ? true : undefined,
+      }
+    );
 
   return (
     <div className="z-10 flex-grow p-2 md:p-4">
@@ -18,7 +28,15 @@ export const ShopRoot = () => {
         {
           {
             loading: <GlobalCircularLoader>Loading</GlobalCircularLoader>,
-            success: <ArticlesList products={data?.products} />,
+            success: (
+              <ArticlesList
+                pages={data?.pages}
+                pageParams={data?.pageParams}
+                fetchNextPage={fetchNextPage}
+                hasNextPage={hasNextPage}
+                isLoading={isFetchingNextPage}
+              />
+            ),
             error: (
               <GlobalIndicator Icon={ErrorCircle}>
                 An error occured while fetching articles

apps/front/src/components/specialized/shop/articles-list/ArticlesList.tsx

@@ -1,21 +1,46 @@
-import { ProductsQueryData } from '@front/api';
+import { Fragment } from 'react';
 
+import { ProductsByPageQuery } from '@front/api';
+
+import {
+  LoadMoreProducts,
+  LoadMoreProductsProps,
+} from '../load-more-products/LoadMoreProducts';
 import { Article } from './article/Article';
 
-type ArticlesListProps = {
-  products?: ProductsQueryData;
-};
+interface ArticlesListProps extends Omit<LoadMoreProductsProps, 'hasMoreData'> {
+  pages?: ProductsByPageQuery[];
+}
 
-export const ArticlesList = ({ products }: ArticlesListProps) => {
-  if (!products) {
+export const ArticlesList = ({
+  pages,
+  pageParams,
+  fetchNextPage,
+  hasNextPage,
+  isLoading,
+}: ArticlesListProps) => {
+  if (!pages) {
     return null;
   }
 
   return (
-    <div className="grid place-content-center gap-3 sm:grid-cols-2 md:grid-cols-3 lg:grid-cols-4 xl:grid-cols-5">
-      {products.map((p) => (
-        <Article key={p.id} {...p} />
-      ))}
-    </div>
+    <>
+      <div className="grid place-content-center gap-3 sm:grid-cols-2 md:grid-cols-3 lg:grid-cols-4 xl:grid-cols-5">
+        {pages.map(({ productsByPage }) => (
+          <Fragment key={productsByPage.id}>
+            {productsByPage.data.map((p) => (
+              <Article key={p.id} {...p} />
+            ))}
+          </Fragment>
+        ))}
+      </div>
+      <LoadMoreProducts
+        hasMoreData={pages.at(-1)?.productsByPage.hasMoreData}
+        fetchNextPage={fetchNextPage}
+        hasNextPage={hasNextPage}
+        pageParams={pageParams}
+        isLoading={isLoading}
+      />
+    </>
   );
 };

apps/front/src/components/specialized/shop/graphql/get-products-by-page.query.graphql

@@ -0,0 +1,18 @@
+query ProductsByPage($offset: Int!, $limit: Int!) {
+  productsByPage(pagination: { offset: $offset, limit: $limit }) {
+    id
+    data {
+      id
+      name
+      description
+      image
+      price
+      stock
+      category {
+        id
+        name
+      }
+    }
+    hasMoreData
+  }
+}

apps/front/src/components/specialized/shop/graphql/get-product.query.graphql → apps/front/src/components/specialized/shop/graphql/get-products.query.graphql

@@ -1,10 +1,11 @@
-query Product($id: Int!) {
-  product(id: $id) {
+query Products {
+  products {
     id
     name
     description
     image
     price
+    stock
     category {
       id
       name