Implemented FixedWindow throttling

analog-nico · Sep 28, 2015 · 84a2a20 · 84a2a20
1 parent 1eaf310
commit 84a2a20
Show file tree

Hide file tree

Showing 7 changed files with 375 additions and 30 deletions.
diff --git a/lib/server/core/presets/google-analytics.js b/lib/server/core/presets/google-analytics.js
@@ -1,6 +1,7 @@
 'use strict';
 
 var _ = require('lodash');
+var moment = require('moment');
 
 var Manager = require('../manager.js');
 var Rule = require('../rule.js');
@@ -27,7 +28,10 @@ var generalRuleQPD = null,
  */
 module.exports = function (options) {
 
-    // TODO: Note: Daily quotas refresh at midnight PST.
+    // Note: Daily quotas refresh at midnight PST.
+    function getStartOfNextWindow() {
+        return moment.utc().startOf('day').add(1, 'day').add(8, 'hours').valueOf();
+    }
 
     _.defaults(options, {
         api: '',
@@ -52,8 +56,10 @@ module.exports = function (options) {
     if (generalRuleQPD === null) {
         generalRuleQPD = new Rule({
             limit: options.dailyRequests,
-            window: 24*60*60*1000,
-            throttling: 'window-fixed',
+            throttling: {
+                type: 'window-fixed',
+                getStartOfNextWindow: getStartOfNextWindow
+            },
             resource: 'requests'
         });
     }
@@ -89,8 +95,10 @@ module.exports = function (options) {
         // 500 write requests per project per day – can be increased
         manager.addRule({
             limit: options.dailyWrites,
-            window: 24*60*60*1000,
-            throttling: 'window-fixed',
+            throttling: {
+                type: 'window-fixed',
+                getStartOfNextWindow: getStartOfNextWindow
+            },
             resource: 'writeRequests'
         });
 
@@ -123,8 +131,11 @@ module.exports = function (options) {
         // 50 upload operations per property per day
         manager.addRule({
             limit: 50,
-            window: 24*60*60*1000,
-            throttling: 'window-fixed',
+            getStartOfNextWindow: getStartOfNextWindow,
+            throttling: {
+                type: 'window-fixed',
+                getStartOfNextWindow: getStartOfNextWindow
+            },
             scope: ['userId', 'propertyId'],
             resource: 'writeRequests'
         });
@@ -141,8 +152,11 @@ module.exports = function (options) {
         // 100 unsampled reports per day per property
         manager.addRule({
             limit: 100,
-            window: 24*60*60*1000,
-            throttling: 'window-fixed',
+            getStartOfNextWindow: getStartOfNextWindow,
+            throttling: {
+                type: 'window-fixed',
+                getStartOfNextWindow: getStartOfNextWindow
+            },
             scope: ['userId', 'propertyId'],
             resource: 'unsampledReports'
         });
@@ -155,8 +169,10 @@ module.exports = function (options) {
         // 50 requests per project per day
         manager.addRule({
             limit: 50,
-            window: 24*60*60*1000,
-            throttling: 'window-fixed',
+            throttling: {
+                type: 'window-fixed',
+                getStartOfNextWindow: getStartOfNextWindow
+            },
             resource: 'writeRequests'
         });
 
@@ -169,8 +185,10 @@ module.exports = function (options) {
         // 10,000 requests per view (profile) per day
         manager.addRule({
             limit: 10000,
-            window: 24*60*60*1000,
-            throttling: 'window-fixed',
+            throttling: {
+                type: 'window-fixed',
+                getStartOfNextWindow: getStartOfNextWindow
+            },
             scope: 'viewId',
             resource: 'requests'
         });

diff --git a/lib/server/core/presets/google-plus.js b/lib/server/core/presets/google-plus.js
@@ -1,7 +1,10 @@
 'use strict';
 
-var Manager = require('../manager.js');
 var _ = require('lodash');
+var moment = require('moment');
+
+var Manager = require('../manager.js');
+
 
 /**
  * Quota Preset for Google+
@@ -18,7 +21,10 @@ var _ = require('lodash');
  */
 module.exports = function (options) {
 
-    // TODO: Note: Daily quotas refresh at midnight PST.
+    // Note: Daily quotas refresh at midnight PST.
+    function getStartOfNextWindow() {
+        return moment.utc().startOf('day').add(1, 'day').add(8, 'hours').valueOf();
+    }
 
     var manager = new Manager({
         backoff: 'timeout'
@@ -28,15 +34,17 @@ module.exports = function (options) {
 
     manager.addRule({
         limit: 20000000,
-        window: 24*60*60*1000,
-        throttling: 'window-fixed',
+        throttling: {
+            type: 'window-fixed',
+            getStartOfNextWindow: getStartOfNextWindow
+        },
         resource: 'signInRequests'
     });
 
     manager.addRule({
         limit: 5,
         window: 1000,
-        throttling: 'window-fixed',
+        throttling: 'window-sliding',
         queueing: 'fifo',
         scope: 'userId',
         resource: 'signInRequests'
@@ -46,15 +54,17 @@ module.exports = function (options) {
 
     manager.addRule({
         limit: 10000,
-        window: 24*60*60*1000,
-        throttling: 'window-fixed',
+        throttling: {
+            type: 'window-fixed',
+            getStartOfNextWindow: getStartOfNextWindow
+        },
         resource: 'requests'
     });
 
     manager.addRule({
         limit: 5,
         window: 1000,
-        throttling: 'window-fixed',
+        throttling: 'window-sliding',
         queueing: 'fifo',
         scope: 'userId',
         resource: 'requests'

diff --git a/lib/server/core/presets/twitter.js b/lib/server/core/presets/twitter.js
@@ -35,7 +35,7 @@ module.exports = function (options) {
         manager.addRule({
             limit: options.authenticated ? authQuota : noAuthQuota,
             window: 15*60*1000,
-            throttling: 'window-fixed', // TODO: Consider feeding back of X-Rate-Limit-Reset
+            throttling: 'window-sliding', // TODO: Consider feeding back of X-Rate-Limit-Reset
             queueing: 'fifo',
             scope: options.authenticated ? 'userId' : [],
             resource: resource

diff --git a/lib/server/core/presets/youtube.js b/lib/server/core/presets/youtube.js
@@ -1,7 +1,10 @@
 'use strict';
 
-var Manager = require('../manager.js');
 var _ = require('lodash');
+var moment = require('moment');
+
+var Manager = require('../manager.js');
+
 
 /**
  * Quota Preset for YouTube Analytics API
@@ -21,7 +24,10 @@ var _ = require('lodash');
  */
 module.exports = function (options) {
 
-    // TODO: Note: Daily quotas refresh at midnight PST.
+    // Note: Daily quotas refresh at midnight PST.
+    function getStartOfNextWindow() {
+        return moment.utc().startOf('day').add(1, 'day').add(8, 'hours').valueOf();
+    }
 
     _.defaults(options, {
         requestsPerSecondPerUser: 12
@@ -33,8 +39,10 @@ module.exports = function (options) {
 
     manager.addRule({
         limit: 100000,
-        window: 24*60*60*1000,
-        throttling: 'window-fixed',
+        throttling: {
+            type: 'window-fixed',
+            getStartOfNextWindow: getStartOfNextWindow
+        },
         resource: 'requests'
     });
 

diff --git a/lib/server/core/throttling/window-fixed.js b/lib/server/core/throttling/window-fixed.js
@@ -1,4 +1,74 @@
-// Strategies: cutoff, linear-remaining, twice-average-remaining
+'use strict';
 
-// TODO: Proper implementation
-module.exports = require('./window-sliding.js');
+// Possible strategies: cutoff, linear-remaining, twice-average-remaining
+// Currently implemented strategy: cuttoff
+// A more linear strategy can be produced by just dividing the limit by a certain factor and returning shorter intervals with getStartOfNextWindow.
+
+var _ = require('lodash');
+
+
+function FixedWindow(options, moreAvailableCb) {
+
+    if (_.isUndefined(options.limit)) {
+        throw new Error('Please pass the limit parameter to allow window-fixed throttling');
+    }
+
+    if (!_.isFunction(options.getStartOfNextWindow)) {
+        throw new Error('Please pass a function as the getStartOfNextWindow parameter to allow window-fixed throttling');
+    }
+
+    this._limit = options.limit;
+    this._used = _.isFinite(options.used) ? options.used : 0;
+    this._moreAvailableCb = moreAvailableCb;
+    this._getStartOfNextWindow = options.getStartOfNextWindow;
+
+    this._prepareNextWindow();
+
+}
+
+FixedWindow.prototype.isAvailable = function (resourceAmount, options) {
+    return this._used + resourceAmount <= this._limit;
+};
+
+FixedWindow.prototype.reserve = function (resourceAmount, options) {
+
+    this._used += resourceAmount;
+
+    var self = this;
+    return function (feedback) {
+
+        if (!_.isUndefined(feedback.limit)) {
+
+            if (!_.isFinite(feedback.limit) || feedback.limit <= 0) {
+                throw new Error('Please pass a positive number as the limit parameter');
+            }
+
+            var limitIncreased = feedback.limit > self._limit;
+
+            self._limit = feedback.limit;
+
+            if (limitIncreased && self._used < self._limit) {
+                self._moreAvailableCb();
+            }
+
+        }
+
+    };
+
+};
+
+FixedWindow.prototype._prepareNextWindow = function () {
+
+    var time = this._getStartOfNextWindow();
+
+    var self = this;
+    setTimeout(function () {
+        self._used = 0;
+        self._prepareNextWindow();
+        self._moreAvailableCb();
+    }, time - (new Date()).getTime()).unref();
+
+};
+
+
+module.exports = FixedWindow;
diff --git a/package.json b/package.json
@@ -27,7 +27,8 @@
   "dependencies": {
     "bluebird": "^2.10",
     "double-ended-queue": "2.1.0-0",
-    "lodash": "^3.10"
+    "lodash": "^3.10",
+    "moment": "^2.10.6"
   },
   "engines": {
     "node": ">=0.10.0"