init

src/uploadLimits.js

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+import crypto from 'node:crypto';
+import fs from 'node:fs/promises';
+import path from 'node:path';
+import { HttpError } from './errors.js';
+
+const HOUR_LIMIT = 5;
+const DAY_LIMIT = 10;
+const GLOBAL_DAY_LIMIT = 100;
+
+export async function createUploadLimiter({ dataDir }) {
+  const filePath = path.join(path.resolve(dataDir), 'index', 'upload-limits.json');
+  await fs.mkdir(path.dirname(filePath), { recursive: true });
+  let state = await loadState(filePath);
+  let writeChain = Promise.resolve();
+
+  return {
+    async checkAndConsume(ip) {
+      const now = new Date();
+      const day = now.toISOString().slice(0, 10);
+      const hour = now.toISOString().slice(0, 13);
+      const key = crypto.createHash('sha256').update(ip || 'unknown').digest('hex');
+
+      if (state.day !== day) state = { day, global: 0, clients: {} };
+      const client = state.clients[key] || { day, dayCount: 0, hour, hourCount: 0 };
+      if (client.day !== day) {
+        client.day = day;
+        client.dayCount = 0;
+      }
+      if (client.hour !== hour) {
+        client.hour = hour;
+        client.hourCount = 0;
+      }
+
+      if (state.global >= GLOBAL_DAY_LIMIT) {
+        throw new HttpError(429, 'Daily site upload budget reached. Try again tomorrow.');
+      }
+      if (client.hourCount >= HOUR_LIMIT) {
+        throw new HttpError(429, 'Upload limit reached: 5 images per hour.');
+      }
+      if (client.dayCount >= DAY_LIMIT) {
+        throw new HttpError(429, 'Upload limit reached: 10 images per day.');
+      }
+
+      state.global += 1;
+      client.hourCount += 1;
+      client.dayCount += 1;
+      state.clients[key] = client;
+      writeChain = writeChain.then(() => fs.writeFile(filePath, `${JSON.stringify(state, null, 2)}\n`));
+      await writeChain;
+
+      return {
+        remainingHour: Math.max(0, HOUR_LIMIT - client.hourCount),
+        remainingDay: Math.max(0, DAY_LIMIT - client.dayCount),
+        remainingGlobalDay: Math.max(0, GLOBAL_DAY_LIMIT - state.global)
+      };
+    }
+  };
+}
+
+async function loadState(filePath) {
+  try {
+    return JSON.parse(await fs.readFile(filePath, 'utf8'));
+  } catch {
+    return { day: new Date().toISOString().slice(0, 10), global: 0, clients: {} };
+  }
+}