afd - npm Package Compare versions

Comparing version 0.2.4 to 0.2.5

build/build.css

build/build.js

+/**
+ * Require the given path.
+ *
+ * @param {String} path
+ * @return {Object} exports
+ * @api public
+ */
+
+function require(p, parent, orig){
+  var path = require.resolve(p)
+    , mod = require.modules[path];
+
+  // lookup failed
+  if (null == path) {
+    orig = orig || p;
+    parent = parent || 'root';
+    throw new Error('failed to require "' + orig + '" from "' + parent + '"');
+  }
+
+  // perform real require()
+  // by invoking the module's
+  // registered function
+  if (!mod.exports) {
+    mod.exports = {};
+    mod.client = mod.component = true;
+    mod.call(this, mod, mod.exports, require.relative(path));
+  }
+
+  return mod.exports;
+}
+
+/**
+ * Registered modules.
+ */
+
+require.modules = {};
+
+/**
+ * Registered aliases.
+ */
+
+require.aliases = {};
+
+/**
+ * Resolve `path`.
+ *
+ * Lookup:
+ *
+ *   - PATH/index.js
+ *   - PATH.js
+ *   - PATH
+ *
+ * @param {String} path
+ * @return {String} path or null
+ * @api private
+ */
+
+require.resolve = function(path){
+  var orig = path
+    , reg = path + '.js'
+    , regJSON = path + '.json'
+    , index = path + '/index.js'
+    , indexJSON = path + '/index.json';
+
+  return require.modules[reg] && reg
+    || require.modules[regJSON] && regJSON
+    || require.modules[index] && index
+    || require.modules[indexJSON] && indexJSON
+    || require.modules[orig] && orig
+    || require.aliases[index];
+};
+
+/**
+ * Normalize `path` relative to the current path.
+ *
+ * @param {String} curr
+ * @param {String} path
+ * @return {String}
+ * @api private
+ */
+
+require.normalize = function(curr, path) {
+  var segs = [];
+
+  if ('.' != path.charAt(0)) return path;
+
+  curr = curr.split('/');
+  path = path.split('/');
+
+  for (var i = 0; i < path.length; ++i) {
+    if ('..' == path[i]) {
+      curr.pop();
+    } else if ('.' != path[i] && '' != path[i]) {
+      segs.push(path[i]);
+    }
+  }
+
+  return curr.concat(segs).join('/');
+};
+
+/**
+ * Register module at `path` with callback `fn`.
+ *
+ * @param {String} path
+ * @param {Function} fn
+ * @api private
+ */
+
+require.register = function(path, fn){
+  require.modules[path] = fn;
+};
+
+/**
+ * Alias a module definition.
+ *
+ * @param {String} from
+ * @param {String} to
+ * @api private
+ */
+
+require.alias = function(from, to){
+  var fn = require.modules[from];
+  if (!fn) throw new Error('failed to alias "' + from + '", it does not exist');
+  require.aliases[to] = from;
+};
+
+/**
+ * Return a require function relative to the `parent` path.
+ *
+ * @param {String} parent
+ * @return {Function}
+ * @api private
+ */
+
+require.relative = function(parent) {
+  var p = require.normalize(parent, '..');
+
+  /**
+   * lastIndexOf helper.
+   */
+
+  function lastIndexOf(arr, obj){
+    var i = arr.length;
+    while (i--) {
+      if (arr[i] === obj) return i;
+    }
+    return -1;
+  }
+
+  /**
+   * The relative require() itself.
+   */
+
+  function fn(path){
+    var orig = path;
+    path = fn.resolve(path);
+    return require(path, parent, orig);
+  }
+
+  /**
+   * Resolve relative to the parent.
+   */
+
+  fn.resolve = function(path){
+    // resolve deps by returning
+    // the dep in the nearest "deps"
+    // directory
+    if ('.' != path.charAt(0)) {
+      var segs = parent.split('/');
+      var i = lastIndexOf(segs, 'deps') + 1;
+      if (!i) i = 0;
+      path = segs.slice(0, i + 1).join('/') + '/deps/' + path;
+      return path;
+    }
+    return require.normalize(p, path);
+  };
+
+  /**
+   * Check if module is defined at `path`.
+   */
+
+  fn.exists = function(path){
+    return !! require.modules[fn.resolve(path)];
+  };
+
+  return fn;
+};require.register("afd/lib/afd.js", function(module, exports, require){
+/**
+ * Accrual Failure Detector
+ * @module afd
+ */
+
+
+/**
+ * @constructor
+ * @param {Number} {ws=100} How many heartbeat intervals we keep track of (window size)
+ * @param {Number} {last=Date.now()} Last report timestamp
+ */
+var afd = function (ws, last) {
+  if(!exists(last)) last = Date.now()
+  if(!exists(ws)) ws = 100
+  
+  this._ws = ws
+  this._last = last
+  this._intervals = Array()
+  this._variance = -1
+  this._mean = -1
+}
+
+/**
+ * Report a received heartbeat
+ * @param {Number} when
+ */
+afd.prototype.report = function (when) {
+  if(this._intervals.length > this._ws) this.intervals.shift()
+  if(!when) when = Date.now()
+
+  var interval = when - this._last
+  this._intervals.push(interval)
+  this._last = when
+  
+  if(!this._intervals.length) return
+  
+  this._variance = this.variance()
+  this._mean = this.mean()
+}
+
+/**
+ * Get the current phi to determine failure
+ * See {@link https://issues.apache.org/jira/browse/CASSANDRA-2597 CASSANDRA-2597} for an explanation of the math at work here.
+ * Using 1 as a threshold means the likeliness of mistaken failure is 10%
+ * Using 2 as a threshold means the likeliness of mistaken failure is 1%
+ * Using 3 as a threshold means the likeliness of mistaken failure is 0.1%
+ *
+ * @param {Number} when
+ */
+afd.prototype.phi = function (when) {
+  // We haven't yet got any data via report.
+  if(this._mean === -1) return -1
+  if(!when) when = Date.now()
+  
+  var interval = when - this._last
+  
+  // If it's only 5 seconds from the start - let's give the system some
+  // slack and allow it to fuck up.
+  if((this._intervals.length < 3) && (interval < 5000)) return 0
+  
+  var probability = Math.pow(Math.E, -1 * interval / this._mean)
+
+  return (-1) * (Math.log(probability) / Math.LN10)
+}
+
+/**
+ * Get the mean interval
+ * @returns mean
+ */
+afd.prototype.mean = function () {
+  return this._intervals.reduce(function (prev, curr) {
+    return prev + curr
+  }) / this._intervals.length
+}
+
+/**
+ * Get the variance
+ * @returns variance
+ */
+afd.prototype.variance = function () {
+  var mean = this._mean
+  
+  return this._intervals.reduce(function (prev, curr) {
+    var x = curr - mean
+    return prev + (x * x)
+  }) / this._intervals.length
+}
+
+
+/**
+ * Exports the afd constructor
+ */
+module.exports = function (ws, last) {
+  return new afd(ws, last)
+}
+
+var exists = function (e) {
+  return !((typeof e === 'undefined') || (e === null))
+}
+});
+require.alias("afd/lib/afd.js", "afd/index.js");

component.json

@@ -5,3 +5,3 @@ {
   "description": "Accrual Failure Detector",
-  "version": "0.2.4",
+  "version": "0.2.5",
   "keywords": [
@@ -8,0 +8,0 @@ "accrual",

lib/afd.js

@@ -34,7 +34,2 @@ /**
   this._last = when
-  
-  if(!this._intervals.length) return
-  
-  this._variance = this.variance()
-  this._mean = this.mean()
 }
@@ -52,4 +47,2 @@
 afd.prototype.phi = function (when) {
-  // We haven't yet got any data via report.
-  if(this._mean === -1) return -1
   if(!when) when = Date.now()
@@ -63,2 +56,5 @@
   
+  this._variance = this.variance()
+  this._mean = this.mean()
+  
   var probability = Math.pow(Math.E, -1 * interval / this._mean)
@@ -65,0 +61,0 @@

package.json

 {
   "name": "afd",
-  "version": "0.2.4",
+  "version": "0.2.5",
   "description": "Accrual Failure Detector",
@@ -58,10 +58,24 @@ "keywords": [
     "jscoverage": "0.3.x",
+    "component": "0.16.x",
     "coveralls": "2.0.x",
     "mocha": "1.10.x",
-    "chai": "1.6.x",
-    "component": "~0.16.2"
+    "chai": "1.6.x"
   },
   "engines": {
     "node": ">=0.8"
+  },
+  "testling": {
+    "harness" : "mocha",
+    "files": "test/*.js",
+    "browsers": {
+      "ie": [8, 9, 10, 11],
+      "chrome": [20, 21, 22, 23, 24, 25, "canary"],
+      "firefox": [26, 17, 18, 19, "nightly"],
+      "safari": [4.0, 5.1, 6.0],
+      "opera": [10, 11, 12, "next"],
+      "iphone": [6.0],
+      "ipad": [6.0],
+      "android-browser": [4.2]
+    }
   }
-}
+}

readme.md

@@ -8,2 +8,5 @@ # Accrual Failure Detector
 
+
+[![browser support](https://ci.testling.com/kordon/afd.png)](https://ci.testling.com/kordon/afd)
+
 ## install
@@ -10,0 +13,0 @@

test/cassandra.js

@@ -15,2 +15,3 @@ var afd = process.env.AFD_COVERAGE ? require('../lib-cov/afd.js') : require('..'),
   var actual = peer.phi(666);
+
   assert.ok(expected - 0.01 <= actual && actual <= expected + 0.01);
@@ -17,0 +18,0 @@

test/obvious.js

@@ -11,2 +11,4 @@ var afd = process.env.AFD_COVERAGE ? require('../lib-cov/afd.js') : require('..'),
     }
+    
+    peer.phi()
   })
@@ -13,0 +15,0 @@

New alerts

Dynamic require

Supply chain risk

Dynamic require can indicate the package is performing dangerous or unsafe dynamic code execution.

Found 1 instance in 1 package

Environment variable access

Supply chain risk

Package accesses environment variables, which may be a sign of credential stuffing or data theft.

Found 1 instance in 1 package

Long strings

Supply chain risk

Contains long string literals, which may be a sign of obfuscated or packed code.

Found 1 instance in 1 package

URL strings

Supply chain risk

Package contains fragments of external URLs or IP addresses, which the package may be accessing at runtime.

Found 1 instance in 1 package

Fixed alerts

Environment variable access

Supply chain risk

Package accesses environment variables, which may be a sign of credential stuffing or data theft.

Found 1 instance in 1 package

Improved metrics

Total package byte prevSize

39671

19.15%

Number of package files

18

12.5%

Lines of code

386

157.33%

Number of lines in readme file

47

6.82%

Worsened metrics

Number of low supply chain risk alerts

8

300%

No dependency changes