fix(contacts): queue VCF import saves

src/app/contacts-app/contacts-app.component.spec.ts

@@ -0,0 +1,59 @@
+// --------- BEGIN RUNBOX LICENSE ---------
+// Copyright (C) 2016-2026 Runbox Solutions AS (runbox.com).
+//
+// This file is part of Runbox 7.
+//
+// Runbox 7 is free software: You can redistribute it and/or modify it
+// under the terms of the GNU General Public License as published by the
+// Free Software Foundation, either version 3 of the License, or (at your
+// option) any later version.
+//
+// Runbox 7 is distributed in the hope that it will be useful, but
+// WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+// General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Runbox 7. If not, see <https://www.gnu.org/licenses/>.
+// ---------- END RUNBOX LICENSE ----------
+
+import { runContactImportQueue } from './contacts-app.component';
+
+describe('runContactImportQueue', () => {
+    it('limits concurrent contact saves', async () => {
+        const contacts = Array.from({ length: 10 }, (_, i) => i);
+        const started: number[] = [];
+        let activeSaves = 0;
+        let maxActiveSaves = 0;
+
+        await runContactImportQueue(contacts, 3, async contact => {
+            started.push(contact);
+            activeSaves += 1;
+            maxActiveSaves = Math.max(maxActiveSaves, activeSaves);
+
+            await new Promise<void>(resolve => setTimeout(resolve, 0));
+
+            activeSaves -= 1;
+        });
+
+        expect(started).toEqual(contacts);
+        expect(maxActiveSaves).toBe(3);
+    });
+
+    it('falls back to a single worker for invalid concurrency limits', async () => {
+        const contacts = [1, 2, 3];
+        let activeSaves = 0;
+        let maxActiveSaves = 0;
+
+        await runContactImportQueue(contacts, 0, async () => {
+            activeSaves += 1;
+            maxActiveSaves = Math.max(maxActiveSaves, activeSaves);
+
+            await new Promise<void>(resolve => setTimeout(resolve, 0));
+
+            activeSaves -= 1;
+        });
+
+        expect(maxActiveSaves).toBe(1);
+    });
+});

src/app/contacts-app/contacts-app.component.ts

@@ -35,6 +35,27 @@ import { VcfImportDialogComponent, VcfImportDialogResult } from './vcf-import-di
 import { v4 as uuidv4 } from 'uuid';
 import { take } from 'rxjs/operators';
 
+const CONTACT_IMPORT_SAVE_CONCURRENCY = 5;
+
+export async function runContactImportQueue<T>(
+    contacts: T[],
+    concurrency: number,
+    saveContact: (contact: T) => Promise<unknown>
+): Promise<void> {
+    const pendingContacts = contacts.slice();
+    const workerCount = Math.min(
+        Math.max(1, concurrency),
+        pendingContacts.length || 1
+    );
+
+    await Promise.all(Array.from({ length: workerCount }, async () => {
+        while (pendingContacts.length > 0) {
+            const contact = pendingContacts.shift();
+            await saveContact(contact);
+        }
+    }));
+}
+
 @Component({
     // eslint-disable-next-line @angular-eslint/component-selector
     selector: 'contacts-app-root',
@@ -278,7 +299,7 @@ export class ContactsAppComponent {
             if (!result) {
                 return;
             }
-            const promises = [];
+            const contactsToImport: Contact[] = [];
             for (const c of contacts) {
                 // Assign an uuid unless it already has one.
                 // Without it we won't be able to add them to groups if requested
@@ -296,10 +317,14 @@ export class ContactsAppComponent {
                     if (result.newCategory) {
                         c.categories = c.categories.concat(result.newCategory);
                     }
-                    promises.push(this.contactsservice.saveContact(c, false));
+                    contactsToImport.push(c);
                 }
             }
-            Promise.all(promises).finally(() => this.contactsservice.reload());
+            runContactImportQueue(
+                contactsToImport,
+                CONTACT_IMPORT_SAVE_CONCURRENCY,
+                contact => this.contactsservice.saveContact(contact, false)
+            ).finally(() => this.contactsservice.reload());
             if (result.addToGroup) {
                 this.addContactsToGroup(result.addToGroup, contacts);
             }