From 4bfc6e21208edc5869dd3a607ce84261de293c46 Mon Sep 17 00:00:00 2001
From: Sven <sgiersig@icloud.com>
Date: Sun, 3 May 2026 12:36:28 +0200
Subject: [PATCH] =?UTF-8?q?Add=20patch:=20followers/following=20countDocum?=
 =?UTF-8?q?ents()=20=E2=86=92=20estimatedDocumentCount()?=
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federation-setup.js calls countDocuments() with no filter 4 times for the
AP followers/following collection dispatchers (pagination totalItems + counter).
All are wrapped in cachedQuery() but on cache miss they run full aggregate scans.
estimatedDocumentCount() reads collection metadata — O(1), no scan.
---
 .../patch-ap-collection-count-estimate.mjs    | 77 +++++++++++++++++++
 1 file changed, 77 insertions(+)
 create mode 100644 scripts/patch-ap-collection-count-estimate.mjs

diff --git a/scripts/patch-ap-collection-count-estimate.mjs b/scripts/patch-ap-collection-count-estimate.mjs
new file mode 100644
index 00000000..aeb567af
--- /dev/null
+++ b/scripts/patch-ap-collection-count-estimate.mjs
@@ -0,0 +1,77 @@
+/**
+ * Patch: replace countDocuments() with estimatedDocumentCount() in
+ * federation-setup.js followers/following collection dispatchers.
+ *
+ * All four calls are already wrapped in cachedQuery(), but on cache miss
+ * countDocuments() runs a full aggregate scan. estimatedDocumentCount()
+ * reads collection metadata — O(1).
+ *
+ * Covers: ap_followers (×2) and ap_following (×2) in collection pagination
+ * and counter dispatchers.
+ */
+
+import { access, readFile, writeFile } from "node:fs/promises";
+
+const candidates = [
+  "node_modules/@rmdes/indiekit-endpoint-activitypub/lib/federation-setup.js",
+  "node_modules/@indiekit/indiekit/node_modules/@rmdes/indiekit-endpoint-activitypub/lib/federation-setup.js",
+];
+
+const MARKER = "// [patch] collection-count-estimate";
+
+const replacements = [
+  {
+    old: `          const t = await collections.ap_followers.countDocuments();
+          return [d, t];`,
+    new: `          const t = await collections.ap_followers.estimatedDocumentCount(); ${MARKER}
+          return [d, t];`,
+  },
+  {
+    old: `        return await collections.ap_followers.countDocuments();`,
+    new: `        return await collections.ap_followers.estimatedDocumentCount(); ${MARKER}`,
+  },
+  {
+    old: `          const t = await collections.ap_following.countDocuments();
+          return [d, t];`,
+    new: `          const t = await collections.ap_following.estimatedDocumentCount(); ${MARKER}
+          return [d, t];`,
+  },
+  {
+    old: `        return await collections.ap_following.countDocuments();`,
+    new: `        return await collections.ap_following.estimatedDocumentCount(); ${MARKER}`,
+  },
+];
+
+async function exists(p) {
+  try { await access(p); return true; } catch { return false; }
+}
+
+let patched = false;
+for (const filePath of candidates) {
+  if (!(await exists(filePath))) continue;
+  let src = await readFile(filePath, "utf8");
+  if (src.includes(MARKER)) {
+    console.log(`[postinstall] patch-ap-collection-count-estimate: already applied in ${filePath}`);
+    patched = true;
+    break;
+  }
+  let changed = 0;
+  for (const { old, new: replacement } of replacements) {
+    if (src.includes(old)) {
+      src = src.replace(old, replacement);
+      changed++;
+    }
+  }
+  if (changed === 0) {
+    console.log(`[postinstall] patch-ap-collection-count-estimate: target snippets not found in ${filePath}`);
+    continue;
+  }
+  await writeFile(filePath, src, "utf8");
+  console.log(`[postinstall] patch-ap-collection-count-estimate: applied ${changed}/4 replacements in ${filePath}`);
+  patched = true;
+  break;
+}
+
+if (!patched) {
+  console.log("[postinstall] patch-ap-collection-count-estimate: no target file found");
+}