Add support for qBittorrent API key (#832)

code/frontend/src/app/core/feature-badges/feature-registry.ts

@@ -50,4 +50,5 @@ export const NEW_FEATURES: NewFeature[] = [
   { id: 'change-username' },
   { id: 'force-import' },
   { id: 'usenet-queue-cleaner' },
+  { id: 'qbit-api-key' },
 ];

code/frontend/src/app/features/settings/download-clients/download-clients.component.html

@@ -83,8 +83,9 @@
     }
     @if (showApiKeyField()) {
       <app-input label="API Key" placeholder="Enter API key" type="password" [revealable]="false" [formField]="clientForm.apiKey"
-        [hint]="apiKeyHint"
+        [hint]="apiKeyHint()"
         [error]="clientForm.apiKey().errors()[0]?.message"
+        [featureId]="apiKeyFeatureId()"
         helpKey="download-client:apiKey" />
     }
     <app-input label="URL Base" placeholder="/api/v2" [formField]="clientForm.urlBase"

code/frontend/src/app/features/settings/download-clients/download-clients.component.spec.ts

@@ -42,7 +42,9 @@ const TYPES: DownloadClientTypesResponse = {
   types: [
     {
       typeName: DownloadClientTypeName.qBittorrent,
-      authFields: [DownloadClientAuthField.Username, DownloadClientAuthField.Password],
+      authFields: [
+        DownloadClientAuthField.Username, DownloadClientAuthField.Password, DownloadClientAuthField.ApiKey,
+      ],
       capabilities: [DownloadClientCapability.SeedingCleanup, DownloadClientCapability.TagFiltering],
     },
     {
@@ -253,6 +255,10 @@ describe('DownloadClientsComponent', () => {
     expect(fieldLabels(fixture)).not.toContain('Username');
     expect(fieldLabels(fixture)).not.toContain('Password');
     expect(fieldLabels(fixture)).toContain('API Key');
+
+    component.clientForm.apiKey().value.set('sab-key');
+    fixture.detectChanges();
+    expect(hintFor(fixture, 'API Key')).toBe('API key from SABnzbd > Config > General');
   });
 
   it('blocks saving a SABnzbd client with an empty API key and shows the error', () => {
@@ -315,11 +321,112 @@ describe('DownloadClientsComponent', () => {
     component.openAddModal();
     fixture.detectChanges();
 
-    expect(component.clientModel().typeName).toBe(DownloadClientTypeName.qBittorrent);
+    chooseClientType(fixture, 'Deluge');
+
+    expect(component.clientModel().typeName).toBe(DownloadClientTypeName.Deluge);
     expect(component.showApiKeyField()).toBe(false);
     expect(fieldLabels(fixture)).not.toContain('API Key');
   });
 
+  it('shows the API key field for qBittorrent alongside username and password', () => {
+    const { fixture, component } = setup();
+
+    component.openAddModal();
+    fixture.detectChanges();
+
+    expect(component.clientModel().typeName).toBe(DownloadClientTypeName.qBittorrent);
+    expect(component.showUsernameField()).toBe(true);
+    expect(component.showPasswordField()).toBe(true);
+    expect(component.showApiKeyField()).toBe(true);
+    expect(fieldLabels(fixture)).toContain('API Key');
+    expect(hintFor(fixture, 'API Key'))
+      .toBe('qBittorrent 5.2+: Options > WebUI > API key. Leave username and password empty.');
+  });
+
+  it('blocks saving a qBittorrent client with both an API key and a password', () => {
+    const { fixture, component, api } = setup();
+
+    component.openAddModal();
+    component.clientForm.name().value.set('qbit box');
+    component.clientForm.host().value.set('http://localhost:8080');
+    component.clientForm.password().value.set('secret');
+    component.clientForm.apiKey().value.set('qbit-key');
+    fixture.detectChanges();
+
+    expect(component.hasModalErrors()).toBe(true);
+    expect(component.clientForm.apiKey().errors()[0].message)
+      .toBe('Use either an API key or a username and password, not both');
+
+    component.saveClient();
+    expect(api.create).not.toHaveBeenCalled();
+  });
+
+  it('saves a qBittorrent client with only an API key', () => {
+    const { fixture, component, api } = setup();
+
+    component.openAddModal();
+    component.clientForm.name().value.set('qbit box');
+    component.clientForm.host().value.set('http://localhost:8080');
+    component.clientForm.apiKey().value.set('qbit-key');
+    fixture.detectChanges();
+
+    expect(component.hasModalErrors()).toBe(false);
+
+    component.saveClient();
+    fixture.detectChanges();
+
+    expect(api.create).toHaveBeenCalledWith(
+      expect.objectContaining({
+        typeName: DownloadClientTypeName.qBittorrent,
+        apiKey: 'qbit-key',
+      }),
+    );
+  });
+
+  it('blocks saving a qBittorrent client with both an API key and a username', () => {
+    const { fixture, component, api } = setup();
+
+    component.openAddModal();
+    component.clientForm.name().value.set('qbit box');
+    component.clientForm.host().value.set('http://localhost:8080');
+    component.clientForm.username().value.set('admin');
+    component.clientForm.apiKey().value.set('qbit-key');
+    fixture.detectChanges();
+
+    expect(component.hasModalErrors()).toBe(true);
+    expect(component.clientForm.apiKey().errors()[0].message)
+      .toBe('Use either an API key or a username and password, not both');
+
+    component.saveClient();
+    expect(api.create).not.toHaveBeenCalled();
+  });
+
+  it('edits a qBittorrent client with a null username and an API key placeholder without showing the exclusive error', () => {
+    const qbitApiKeyOnly: ClientConfig = {
+      ...QBIT,
+      username: null as unknown as string,
+      password: undefined,
+      apiKey: 'qbit-placeholder-key',
+    };
+    const { fixture, component, api } = setup(createApi({ clients: [qbitApiKeyOnly] }));
+
+    component.openEditModal(qbitApiKeyOnly);
+    fixture.detectChanges();
+
+    expect(component.hasModalErrors()).toBe(false);
+
+    component.clientForm.name().value.set('qbit box renamed');
+    fixture.detectChanges();
+
+    component.saveClient();
+    fixture.detectChanges();
+
+    expect(api.update).toHaveBeenCalledWith(
+      qbitApiKeyOnly.id,
+      expect.objectContaining({ name: 'qbit box renamed', apiKey: 'qbit-placeholder-key' }),
+    );
+  });
+
   it('saves a SABnzbd client with the Usenet client type', () => {
     const { fixture, component, api } = setup();
 

code/frontend/src/app/features/settings/download-clients/download-clients.component.ts

@@ -1,6 +1,6 @@
 import { Component, ChangeDetectionStrategy, inject, signal, computed } from '@angular/core';
 import { forkJoin } from 'rxjs';
-import { form, required, disabled, FormField } from '@angular/forms/signals';
+import { form, required, disabled, validate, FormField } from '@angular/forms/signals';
 import { PageHeaderComponent } from '@layout/page-header/page-header.component';
 import {
   CardComponent, ButtonComponent, InputComponent, ToggleComponent,
@@ -114,6 +114,15 @@ export class DownloadClientsComponent implements HasPendingChanges {
       when: ({ valueOf }) => valueOf(p.typeName) === DownloadClientTypeName.Sabnzbd,
       message: 'API key is required',
     });
+    validate(p.apiKey, () => {
+      const m = this.clientModel();
+      const fields = this.authFieldsByType()[m.typeName] ?? [];
+      const supportsBoth = fields.includes('apiKey') && (fields.includes('username') || fields.includes('password'));
+      const has = (v: string | null | undefined): boolean => !!v && v.trim() !== '';
+      return supportsBoth && has(m.apiKey) && (has(m.username) || has(m.password))
+        ? { kind: 'exclusive', message: 'Use either an API key or a username and password, not both' }
+        : undefined;
+    });
     disabled(p.typeName, () => this.editingClient() !== null);
   });
 
@@ -133,7 +142,15 @@ export class DownloadClientsComponent implements HasPendingChanges {
   readonly showApiKeyField = computed(() =>
     (this.authFieldsByType()[this.clientModel().typeName] ?? []).includes('apiKey'));
 
-  readonly apiKeyHint = 'API key from SABnzbd > Config > General';
+  readonly apiKeyHint = computed(() => {
+    if (this.clientModel().typeName === DownloadClientTypeName.qBittorrent) {
+      return 'qBittorrent 5.2+: Options > WebUI > API key. Leave username and password empty.';
+    }
+    return 'API key from SABnzbd > Config > General';
+  });
+
+  readonly apiKeyFeatureId = computed(() =>
+    this.clientModel().typeName === DownloadClientTypeName.qBittorrent ? 'qbit-api-key' : undefined);
 
   readonly usernameHint = computed(() => {
     if (this.clientModel().typeName === DownloadClientTypeName.rTorrent) {
@@ -204,7 +221,7 @@ export class DownloadClientsComponent implements HasPendingChanges {
       name: client.name,
       typeName: client.typeName,
       host: client.host,
-      username: client.username,
+      username: client.username ?? '',
       password: client.password ?? '',
       apiKey: client.apiKey ?? '',
       urlBase: client.urlBase,