Initial commit: URL Redirect Tracker application with comprehensive documentation

node_modules/express-rate-limit/lib/memory-store.js

@@ -0,0 +1,47 @@
+"use strict";
+
+function calculateNextResetTime(windowMs) {
+  const d = new Date();
+  d.setMilliseconds(d.getMilliseconds() + windowMs);
+  return d;
+}
+
+function MemoryStore(windowMs) {
+  let hits = {};
+  let resetTime = calculateNextResetTime(windowMs);
+
+  this.incr = function (key, cb) {
+    if (hits[key]) {
+      hits[key]++;
+    } else {
+      hits[key] = 1;
+    }
+
+    cb(null, hits[key], resetTime);
+  };
+
+  this.decrement = function (key) {
+    if (hits[key]) {
+      hits[key]--;
+    }
+  };
+
+  // export an API to allow hits all IPs to be reset
+  this.resetAll = function () {
+    hits = {};
+    resetTime = calculateNextResetTime(windowMs);
+  };
+
+  // export an API to allow hits from one IP to be reset
+  this.resetKey = function (key) {
+    delete hits[key];
+  };
+
+  // simply reset ALL hits every windowMs
+  const interval = setInterval(this.resetAll, windowMs);
+  if (interval.unref) {
+    interval.unref();
+  }
+}
+
+module.exports = MemoryStore;