Add search publication page and fix category access

frontend/src/app/pages/search-publications/search-publications.component.html

@@ -0,0 +1,13 @@
+<h1>Search results</h1>
+@if((isLoading$ | async) === true) {
+    <h2>Search in progress...</h2>
+    <mat-spinner></mat-spinner>
+} @else if((isLoaded$ | async) === true) {
+    @if((publications$ | async)?.length) {
+        <app-publication-list [publications$]="publications$"></app-publication-list>
+    } @else {
+        No any result.
+    }
+} @else {
+    No any result.
+}

frontend/src/app/pages/search-publications/search-publications.component.scss

@@ -0,0 +1,6 @@
+:host {
+    display: flex;
+    flex-direction: column;
+    justify-content: center;
+    align-items: center;
+}

frontend/src/app/pages/search-publications/search-publications.component.ts

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+import { CommonModule } from "@angular/common";
+import { Component, inject, OnDestroy, OnInit } from "@angular/core";
+import { MatProgressSpinner } from "@angular/material/progress-spinner";
+import { ActivatedRoute } from "@angular/router";
+import { Observable, Subscription } from "rxjs";
+import { PublicationListComponent } from "../../components/publication-list/publication-list.component";
+import { Publication } from "../../core/rest-services/publications/model/publication";
+import { SearchPublicationsService } from "./search-publications.service";
+
+@Component({
+    selector: 'app-search-publications',
+    templateUrl: './search-publications.component.html',
+    styleUrl: './search-publications.component.scss',
+    standalone: true,
+    imports: [CommonModule, MatProgressSpinner, PublicationListComponent],
+    providers: [SearchPublicationsService]
+})
+export class SearchPublicationsComponent implements OnInit, OnDestroy {
+    private searchPublicationsService = inject(SearchPublicationsService);
+    private activatedRoute = inject(ActivatedRoute);
+    private queryParamsSubscription?: Subscription;
+
+    ngOnInit(): void {
+        this.queryParamsSubscription = this.activatedRoute.queryParamMap
+            .subscribe(params => {  
+                const categoryId = params.get('category-id');
+                if (categoryId) {
+                    this.searchPublicationsService.loadPublications(`category_id=${categoryId}`);
+                }
+            });
+    }
+
+    ngOnDestroy(): void {
+        this.queryParamsSubscription?.unsubscribe();
+    }
+
+    get publications$(): Observable<Publication[]> {
+        return this.searchPublicationsService.publications$;
+    }
+
+    get isLoading$(): Observable<boolean> {
+        return this.searchPublicationsService.isLoading$;
+    }
+
+    get isLoaded$(): Observable<boolean> {
+        return this.searchPublicationsService.isLoaded$;
+    }
+}

frontend/src/app/pages/search-publications/search-publications.service.ts

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+import { inject, Injectable } from "@angular/core";
+import { PublicationRestService } from "../../core/rest-services/publications/publication.rest-service";
+import { BehaviorSubject, Observable } from "rxjs";
+import { Publication } from "../../core/rest-services/publications/model/publication";
+import { MatSnackBar } from "@angular/material/snack-bar";
+
+
+@Injectable()
+export class SearchPublicationsService {
+    private publicationRestService = inject(PublicationRestService);
+    private publicationsSubject = new BehaviorSubject<Publication[]>([]);
+    private isLoadingSubject = new BehaviorSubject<boolean>(false);
+    private isLoadedSubject = new BehaviorSubject<boolean>(false);
+    private snackBar = inject(MatSnackBar);
+
+    get publications$(): Observable<Publication[]> {
+        return this.publicationsSubject.asObservable();
+    }
+    
+    get isLoading$(): Observable<boolean> {
+        return this.isLoadingSubject.asObservable();
+    }
+
+    get isLoaded$(): Observable<boolean> {
+        return this.isLoadedSubject.asObservable();
+    }
+
+    loadPublications(searchCriteria: string): void {
+         this.isLoadingSubject.next(true);
+         this.isLoadedSubject.next(false);
+         this.publicationsSubject.next([]);
+
+         this.publicationRestService.search(searchCriteria)
+            .then(publications => {
+                this.publicationsSubject.next(publications);
+            })
+            .catch(error => {
+                if (error.status !== 404) {
+                    const errorMessage = 'An error occured while retrieving publications.';
+                    console.error(errorMessage, error);
+                    this.snackBar.open(errorMessage, 'Close', { duration: 5000 });
+                }
+            })
+            .finally(() => {
+                this.isLoadingSubject.next(false);
+                this.isLoadedSubject.next(true);
+            });
+    }
+}