Deduplicate incoming stickers from installed sticker packs

2026-04-19 16:08:34 +01:00 · 2026-02-12 12:36:53 -05:00
parent 95f131efbf
commit ae90a74cef
8 changed files with 235 additions and 194 deletions
--- a/ts/util/attachments/deduplicateAttachment.preload.ts
+++ b/ts/util/attachments/deduplicateAttachment.preload.ts
@@ -0,0 +1,108 @@
+// Copyright 2026 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import { createLogger } from '../../logging/log.std.js';
+import { DataWriter } from '../../sql/Client.preload.js';
+import { doesAttachmentExist } from '../migrations.preload.js';
+
+import { type MIMEType, stringToMIMEType } from '../../types/MIME.std.js';
+import { strictAssert } from '../assert.std.js';
+import { type WithRequiredProperties } from '../../types/Util.std.js';
+import { type AttachmentType } from '../../types/Attachment.std.js';
+import { CURRENT_ATTACHMENT_VERSION } from '../../../app/attachments.node.js';
+
+const log = createLogger('deduplicateAttachment');
+
+type AttachmentDataToBeReused = WithRequiredProperties<
+  Pick<
+    AttachmentType,
+    | 'path'
+    | 'localKey'
+    | 'version'
+    | 'thumbnail'
+    | 'screenshot'
+    | 'width'
+    | 'height'
+  >,
+  'path' | 'localKey' | 'version'
+>;
+
+export async function getExistingAttachmentDataForReuse({
+  plaintextHash,
+  contentType,
+  logId,
+}: {
+  plaintextHash: string;
+  contentType: MIMEType;
+  logId?: string;
+}): Promise<AttachmentDataToBeReused | null> {
+  const existingAttachmentData =
+    await DataWriter.getAndProtectExistingAttachmentPath({
+      plaintextHash,
+      version: CURRENT_ATTACHMENT_VERSION,
+      contentType,
+    });
+
+  if (!existingAttachmentData) {
+    return null;
+  }
+
+  strictAssert(existingAttachmentData.path, 'path must exist for reuse');
+  strictAssert(
+    existingAttachmentData.version === CURRENT_ATTACHMENT_VERSION,
+    'version mismatch'
+  );
+  strictAssert(existingAttachmentData.localKey, 'localKey must exist');
+
+  if (!(await doesAttachmentExist(existingAttachmentData.path))) {
+    log.warn(
+      `${logId}: Existing attachment no longer exists, using newly downloaded one`
+    );
+    return null;
+  }
+
+  log.info(`${logId}: Reusing existing attachment`);
+
+  const dataToReuse: AttachmentDataToBeReused = {
+    path: existingAttachmentData.path,
+    localKey: existingAttachmentData.localKey,
+    version: existingAttachmentData.version,
+    width: existingAttachmentData.width ?? undefined,
+    height: existingAttachmentData.height ?? undefined,
+  };
+  const { thumbnailPath, thumbnailSize, thumbnailContentType } =
+    existingAttachmentData;
+
+  if (
+    thumbnailPath &&
+    thumbnailSize &&
+    thumbnailContentType &&
+    (await doesAttachmentExist(thumbnailPath))
+  ) {
+    dataToReuse.thumbnail = {
+      path: thumbnailPath,
+      localKey: existingAttachmentData.thumbnailLocalKey ?? undefined,
+      version: existingAttachmentData.thumbnailVersion ?? undefined,
+      size: thumbnailSize,
+      contentType: stringToMIMEType(thumbnailContentType),
+    };
+  }
+
+  const { screenshotPath, screenshotSize, screenshotContentType } =
+    existingAttachmentData;
+  if (
+    screenshotPath &&
+    screenshotSize &&
+    screenshotContentType &&
+    (await doesAttachmentExist(screenshotPath))
+  ) {
+    dataToReuse.screenshot = {
+      path: screenshotPath,
+      localKey: existingAttachmentData.screenshotLocalKey ?? undefined,
+      version: existingAttachmentData.screenshotVersion ?? undefined,
+      size: screenshotSize,
+      contentType: stringToMIMEType(screenshotContentType),
+    };
+  }
+  return dataToReuse;
+}