Add infinite query to comments, some endpoint api stuff.

src/app/endpoints.ts

@@ -0,0 +1,3 @@
+export const Endpoints = {
+    recipes: 'recipes',
+};

src/app/model/Query.model.ts

@@ -0,0 +1,11 @@
+export interface QueryParams {
+    page?: number;
+    size?: number;
+    sort?: Array<string | Sort>;
+}
+
+export interface Sort {
+    property: string;
+    order?: 'ASC' | 'DESC';
+    ignoreCase?: boolean;
+}

src/app/model/RecipeComment.model.ts

@@ -1,10 +1,8 @@
 import { ResourceOwner } from './ResourceOwner.model';
+import { SliceView } from './SliceView.model';
 
 export interface RecipeComments {
-    slice: {
+    slice: SliceView;
-        number: number;
-        size: number;
-    };
     content: RecipeComment[];
 }
 

src/app/model/SliceView.model.ts

@@ -0,0 +1,5 @@
+export interface SliceView {
+    hasNext: boolean;
+    number: number;
+    size: number;
+}

src/app/recipe-comments-list/recipe-comments-list.component.html

@@ -14,13 +14,11 @@
         <p>You must be logged in to comment.</p>
     }
     <h3>Comments</h3>
-    @if (commentsQuery.isLoading()) {
+    @if (commentsQuery.isPending()) {
         <p>Loading comments...</p>
     } @else if (commentsQuery.isError()) {
         <p>There was an error loading the comments.</p>
-    } @else if (commentsQuery.isSuccess()) {
+    } @else {
-        @let comments = commentsQuery.data();
-        @if (comments.length) {
         <ul>
             @if (addCommentMutation.isPending()) {
                 <li style="opacity: 0.5">
@@ -28,15 +26,23 @@
                     <div>{{ addCommentMutation.variables() }}</div>
                 </li>
             }
-                @for (comment of comments; track $index) {
+            @for (recipeComments of commentsQuery.data()?.pages; track $index) {
+                @for (recipeComment of recipeComments.content; track recipeComment.id) {
                     <li>
-                        <p>{{ comment.owner.username }} at {{ comment.created }}</p>
+                        <p>{{ recipeComment.owner.username }} at {{ recipeComment.created }}</p>
-                        <div [innerHTML]="comment.text"></div>
+                        <div [innerHTML]="recipeComment.text"></div>
                     </li>
                 }
-            </ul>
-        } @else {
-            <p>There are no comments yet.</p>
             }
+        </ul>
+        <div>
+            @if (commentsQuery.hasNextPage() && !commentsQuery.isFetchingNextPage()) {
+                <button (click)="commentsQuery.fetchNextPage()">Load more comments</button>
+            } @else if (commentsQuery.isFetchingNextPage()) {
+                <p>Loading comments...</p>
+            } @else if (!commentsQuery.hasNextPage()) {
+                <p>No additional comments to load.</p>
+            }
+        </div>
     }
 </div>

src/app/recipe-comments-list/recipe-comments-list.component.ts

@@ -1,8 +1,9 @@
 import { Component, computed, inject, input } from '@angular/core';
 import { FormControl, FormGroup, ReactiveFormsModule, Validators } from '@angular/forms';
 import { RecipeService } from '../service/recipe.service';
-import { injectMutation, injectQuery } from '@tanstack/angular-query-experimental';
+import { injectInfiniteQuery, injectMutation } from '@tanstack/angular-query-experimental';
 import { AuthService } from '../service/auth.service';
+import { RecipeComments } from '../model/RecipeComment.model';
 
 @Component({
     selector: 'app-comments-list',
@@ -20,9 +21,23 @@ export class RecipeCommentsList {
     protected readonly username = this.authService.username;
     protected readonly isLoggedIn = computed(() => !!this.authService.accessToken());
 
-    protected readonly commentsQuery = injectQuery(() => ({
+    protected commentsQuery = injectInfiniteQuery(() => ({
+        initialPageParam: 0,
+        getNextPageParam: (previousPage: RecipeComments) =>
+            previousPage.slice.hasNext ? previousPage.slice.number + 1 : undefined,
         queryKey: ['recipeComments', this.recipeUsername(), this.recipeSlug()],
-        queryFn: () => this.recipeService.getComments(this.recipeUsername(), this.recipeSlug()),
+        queryFn: ({ pageParam }) => {
+            return this.recipeService.getComments(this.recipeUsername(), this.recipeSlug(), {
+                page: pageParam,
+                size: 1,
+                sort: [
+                    {
+                        property: 'created',
+                        order: 'DESC',
+                    },
+                ],
+            });
+        },
     }));
 
     protected readonly addCommentForm = new FormGroup({
@@ -32,6 +47,7 @@ export class RecipeCommentsList {
     protected readonly addCommentMutation = injectMutation(() => ({
         mutationFn: (commentText: string) =>
             this.recipeService.addComment(this.recipeUsername(), this.recipeSlug(), commentText),
+        onSuccess: () => this.commentsQuery.fetchNextPage(),
     }));
 
     protected onCommentSubmit() {

src/app/service/endpoint.service.ts

@@ -0,0 +1,48 @@
+import { Injectable } from '@angular/core';
+import { Endpoints } from '../endpoints';
+import { QueryParams } from '../model/Query.model';
+
+@Injectable({
+    providedIn: 'root',
+})
+export class EndpointService {
+    public getUrl(
+        endpoint: keyof typeof Endpoints,
+        pathParams?: string[],
+        queryParams?: QueryParams,
+    ): string {
+        const urlSearchParams = new URLSearchParams();
+        if (queryParams?.page !== undefined) {
+            urlSearchParams.set('page', queryParams.page.toString());
+        }
+        if (queryParams?.size !== undefined) {
+            urlSearchParams.set('size', queryParams.size.toString());
+        }
+        queryParams?.sort?.forEach((sort) => {
+            if (typeof sort === 'string') {
+                urlSearchParams.append('sort', sort);
+            } else {
+                let sortString = sort.property;
+                if (sort.order) {
+                    sortString += ',' + sort.order;
+                }
+                if (sort.ignoreCase) {
+                    sortString += ',IgnoreCase';
+                }
+                urlSearchParams.append('sort', sortString);
+            }
+        });
+
+        let pathString = pathParams?.join('/');
+        if (pathString?.length) {
+            pathString = '/' + pathString;
+        }
+
+        let queryString = urlSearchParams.toString();
+        if (queryString.length) {
+            queryString = '?' + queryString;
+        }
+
+        return `http://localhost:8080/${Endpoints[endpoint]}${pathString}${queryString}`;
+    }
+}

src/app/service/recipe.service.ts

@@ -5,6 +5,8 @@ import { Recipe, RecipeInfoViews, RecipeView } from '../model/Recipe.model';
 import { AuthService } from './auth.service';
 import { QueryClient } from '@tanstack/angular-query-experimental';
 import { RecipeComment, RecipeComments } from '../model/RecipeComment.model';
+import { QueryParams } from '../model/Query.model';
+import { EndpointService } from './endpoint.service';
 
 @Injectable({
     providedIn: 'root',
@@ -13,6 +15,7 @@ export class RecipeService {
     private readonly http = inject(HttpClient);
     private readonly authService = inject(AuthService);
     private readonly queryClient = inject(QueryClient);
+    private readonly endpointService = inject(EndpointService);
 
     public getRecipes(): Promise<Recipe[]> {
         return firstValueFrom(
@@ -47,11 +50,15 @@ export class RecipeService {
         }
     }
 
-    public getComments(username: string, slug: string): Promise<RecipeComment[]> {
+    public getComments(
+        username: string,
+        slug: string,
+        queryParams?: QueryParams,
+    ): Promise<RecipeComments> {
         return firstValueFrom(
-            this.http
+            this.http.get<RecipeComments>(
-                .get<RecipeComments>(`http://localhost:8080/recipes/${username}/${slug}/comments`)
+                this.endpointService.getUrl('recipes', [username, slug, 'comments'], queryParams),
-                .pipe(map((res) => res.content)),
+            ),
         );
     }