fix user cache

src/app/chat/chat/channel-list/channel-list.component.ts

@@ -1,6 +1,7 @@
-import { Component, EventEmitter, OnChanges, OnInit, Output } from '@angular/core';
+import { Component, EventEmitter, OnChanges, OnDestroy, OnInit, Output } from '@angular/core';
 import { Channel } from '../../../models/channel';
 import { ChatService } from '../../../services/chat.service';
+import { Subject, takeUntil } from 'rxjs';
 
 @Component({
   selector: 'app-channel-list',
@@ -8,22 +9,30 @@ import { ChatService } from '../../../services/chat.service';
   templateUrl: './channel-list.component.html',
   styleUrl: './channel-list.component.scss'
 })
-export class ChannelListComponent implements OnInit {
+export class ChannelListComponent implements OnInit, OnDestroy {
   @Output("select") selectEmitter: EventEmitter<Channel> = new EventEmitter<Channel>();
 
   public channels!: Channel[];
   public selectedChannel?: Channel;
 
+  private destroy = new Subject<void>();
+
   constructor(private chatService: ChatService) { }
 
   ngOnInit() {
     this.chatService.ListChannels()
+      .pipe(takeUntil(this.destroy))
       .subscribe(channels => {
         this.channels = channels;
         this.selectedChannel = this.channels[0];
       });
   }
 
+  ngOnDestroy(): void {
+    this.destroy.next();
+    this.destroy.complete();
+  }
+
   public Select(index: number): void {
     this.selectEmitter.emit(this.selectedChannel = this.channels[index]);
   }

src/app/chat/chat/feed/feed.component.ts

@@ -1,4 +1,4 @@
-import { Component, Input, OnChanges, OnInit } from '@angular/core';
+import { Component, Input, OnChanges, OnDestroy, OnInit } from '@angular/core';
 import { Message } from '../../../models/message';
 import { ChatService } from '../../../services/chat.service';
 import { UserService } from '../../../services/user.service';
@@ -11,7 +11,7 @@ import { Subscription } from 'rxjs';
   templateUrl: './feed.component.html',
   styleUrl: './feed.component.scss'
 })
-export class FeedComponent implements OnChanges {
+export class FeedComponent implements OnChanges, OnDestroy {
   private readonly DEFAULT_CHANNEL_ID: number = 1;
 
   @Input('channel') public channel?: Channel;
@@ -19,7 +19,7 @@ export class FeedComponent implements OnChanges {
 
   public subscription?: Subscription;
 
-  constructor(private chatService: ChatService, private userService: UserService) { }
+  constructor(private chatService: ChatService) { }
 
   ngOnChanges() {
     if (this.subscription) {
@@ -29,6 +29,12 @@ export class FeedComponent implements OnChanges {
 
     this.subscription =
       this.chatService.GetMessages(this.channel?.id ?? this.DEFAULT_CHANNEL_ID)
-      .subscribe(message => this.messages.push(message));
+        .subscribe(message => this.messages.push(message));
+  }
+
+  ngOnDestroy(): void {
+    if (this.subscription) {
+      this.subscription.unsubscribe();
+    }
   }
 }

src/app/chat/chat/feed/message/profile-picture/profile-picture.component.ts

@@ -1,6 +1,7 @@
-import { Component, Input, OnInit } from '@angular/core';
+import { Component, Input, OnDestroy, OnInit } from '@angular/core';
 import { UserService } from '../../../../../services/user.service';
 import { ToastrService } from 'ngx-toastr';
+import { Subject, takeUntil } from 'rxjs';
 
 @Component({
   selector: 'app-profile-picture',
@@ -8,14 +9,17 @@ import { ToastrService } from 'ngx-toastr';
   templateUrl: './profile-picture.component.html',
   styleUrl: './profile-picture.component.scss'
 })
-export class ProfilePictureComponent implements OnInit {
+export class ProfilePictureComponent implements OnInit, OnDestroy {
   @Input("username") public username!: string;
   public url?: string;
 
+  private destroy: Subject<void> = new Subject<void>();
+
   constructor(private userService: UserService, private toastrService: ToastrService) { }
 
   ngOnInit(): void {
     this.userService.GetProfilePictureURL(this.username)
+      .pipe(takeUntil(this.destroy))
       .subscribe({
         next: url => this.url = url,
         error: _ => {
@@ -23,4 +27,9 @@ export class ProfilePictureComponent implements OnInit {
         }
       });
   }
+
+  ngOnDestroy(): void {
+    this.destroy.next();
+    this.destroy.complete();
+  }
 }

src/app/services/user.service.ts

@@ -1,5 +1,5 @@
 import { Injectable } from '@angular/core';
-import { catchError, map, Observable, throwError } from 'rxjs';
+import { catchError, map, Observable, shareReplay, tap, throwError } from 'rxjs';
 import { User } from '../models/user';
 import { HttpClient } from '@angular/common/http';
 import { UserInfoResponse } from './responses/user';
@@ -9,44 +9,38 @@ import { environment } from '../../environment/environment';
   providedIn: 'root'
 })
 export class UserService {
-  private users: Map<string, User> = new Map<string, User>();
+  private users: Map<string, Observable<User>> = new Map<string, Observable<User>>();
 
   constructor(private http: HttpClient) { }
 
   public GetUser(username: string): Observable<User> {
-    if (this.users.has(username)) {
-      return new Observable<User>(subscriber => {
-        subscriber.next(this.users.get(username)!);
-        subscriber.complete();
-      });
+    let user = this.users.get(username);
+    if (user) {
+      return user;
     } else {
       let url = `${environment.apiBase}/user/info/${username}`
-      return this.http.get<UserInfoResponse>(url, { withCredentials: true }).pipe(
-        map(response => {
-          if (response.error) {
-            throw new Error(response.error);
-          }
+      let observable = this.http.get<UserInfoResponse>(url, { withCredentials: true })
+        .pipe(
+          map(response => {
+            if (response.error) {
+              throw new Error(response.error);
+            }
 
-          if (response.user) {
-            this.users.set(username, response.user);
-            return response.user;
-          }
+            if (response.user) {
+              return response.user;
+            }
 
-          throw new Error("bad API response, missing user with no error");
-        }),
-        catchError(error => throwError(() => new Error(error.error.message)))
-      );
+            throw new Error("bad API response, missing user with no error");
+          }),
+          catchError(error => throwError(() => new Error(error.error.message))),
+          shareReplay({ bufferSize: 1, refCount: true })
+        );
+      this.users.set(username, observable);
+      return observable;
     }
   }
 
   public GetProfilePictureURL(username: string): Observable<string> {
-    if (this.users.has(username)) {
-      return new Observable<string>(subscriber => {
-        subscriber.next(this.users.get(username)!.picture);
-        subscriber.complete();
-      });
-    } else {
-      return this.GetUser(username).pipe(map(user => user.picture));
-    }
+    return this.GetUser(username).pipe(map(user => user.picture));
   }
 }