opossum - npm Package Compare versions

Comparing version 1.0.0 to 1.1.0

CHANGELOG.md

@@ -5,2 +5,20 @@ # Change Log
 
+<a name="1.1.0"></a>
+# [1.1.0](https://github.com/bucharest-gold/opossum/compare/v1.0.0...v1.1.0) (2017-06-06)
+
+
+### Bug Fixes
+
+* don't let circuits get stuck half open ([5e1171c](https://github.com/bucharest-gold/opossum/commit/5e1171c))
+* fix logic around pendingClose ([4d89ae4](https://github.com/bucharest-gold/opossum/commit/4d89ae4))
+
+
+### Features
+
+* add ETIMEDOUT error code for timeout error ([#64](https://github.com/bucharest-gold/opossum/issues/64)) ([5df9f65](https://github.com/bucharest-gold/opossum/commit/5df9f65))
+* addition of rolling percentile latency's. GH-ISSUE [#38](https://github.com/bucharest-gold/opossum/issues/38) ([ce7b50d](https://github.com/bucharest-gold/opossum/commit/ce7b50d))
+* remove fidelity promises. ([3f5827a](https://github.com/bucharest-gold/opossum/commit/3f5827a))
+
+
+
 <a name="1.0.0"></a>
@@ -7,0 +25,0 @@ # [1.0.0](https://github.com/bucharest-gold/opossum/compare/v0.6.0...v1.0.0) (2017-04-06)

index.js

@@ -5,3 +5,2 @@ (() => {
   const CircuitBreaker = require('./lib/circuit');
-  const Fidelity = require('fidelity');
 
@@ -11,4 +10,3 @@ const defaults = {
     errorThresholdPercentage: 50,
-    resetTimeout: 30000, // 30 seconds
-    Promise: Fidelity
+    resetTimeout: 30000 // 30 seconds
   };
@@ -30,5 +28,2 @@
    * the breaker to `halfOpen` state, and trying the action again.
-   * @param options.Promise {Promise} Opossum uses Fidelity promises, but works
-   * fine with any Promise that follows the spec. You can specify your favored
-   * implementation by providing the constructor as an option.
    * @return a {@link CircuitBreaker} instance
@@ -35,0 +30,0 @@ */

lib/circuit.js

@@ -42,2 +42,5 @@ 'use strict';
  * @param options.name the name to use for this circuit when reporting stats
+ * @param options.rollingPercentilesEnabled {boolean} This property indicates whether execution latencies
+ *  should be tracked and calculated as percentiles.
+ *  If they are disabled, all summary statistics (mean, percentiles) are returned as -1.
  */
@@ -50,3 +53,3 @@ class CircuitBreaker extends EventEmitter {
     this.options.rollingCountBuckets = options.rollingCountBuckets || 10;
-    this.Promise = options.Promise;
+    this.options.rollingPercentilesEnabled = options.rollingPercentilesEnabled !== false;
 
@@ -61,3 +64,3 @@ this[STATUS] = new Status(this.options);
     if (typeof action !== 'function') {
-      this.action = _ => this.Promise.resolve(action);
+      this.action = _ => Promise.resolve(action);
     } else this.action = action;
@@ -67,3 +70,3 @@
 
-    const increment = property => _ => this[STATUS].increment(property);
+    const increment = property => (result, runTime) => this[STATUS].increment(property, runTime);
 
@@ -91,2 +94,3 @@ this.on('success', increment('successes'));
           circuit[STATE] = HALF_OPEN;
+          circuit[PENDING_CLOSE] = true;
           circuit.emit('halfOpen', circuit.options.resetTimeout);
@@ -101,3 +105,3 @@ }, circuit.options.resetTimeout);
     this.on('open', _startTimer(this));
-    this.on('success', () => this.close());
+    this.on('success', _ => this.close());
     if (this.options.cache) {
@@ -157,2 +161,6 @@ CACHE.set(this, undefined);
 
+  get pendingClose () {
+    return this[PENDING_CLOSE];
+  }
+
   /**
@@ -262,3 +270,3 @@ * True if the circuit is currently closed. False otherwise.
 
-    if (this.opened || (this.halfOpen && this[PENDING_CLOSE])) {
+    if (this.opened && !this.pendingClose) {
       /**
@@ -270,10 +278,11 @@ * Emitted when the circuit breaker is open and failing fast
 
-      return fallback(this, 'Breaker is open', args) ||
+      return fallback(this, 'Breaker is open', args, 0) ||
         Promise.reject(new Error('Breaker is open'));
     }
-    this[PENDING_CLOSE] = this.halfOpen;
+    this[PENDING_CLOSE] = false;
 
     let timeout;
     let timeoutError = false;
-    return new this.Promise((resolve, reject) => {
+    return new Promise((resolve, reject) => {
+      const latencyStartTime = Date.now();
       timeout = setTimeout(
@@ -283,2 +292,3 @@ () => {
           const error = new Error(`Timed out after ${this.options.timeout}ms`);
+          error.code = 'ETIMEDOUT';
           /**
@@ -288,4 +298,5 @@ * Emitted when the circuit breaker action takes longer than `options.timeout`
            */
-          this.emit('timeout', error);
-          resolve(fallback(this, error, args) || fail(this, error, args));
+          const latency = Date.now() - latencyStartTime;
+          this.emit('timeout', error, latency);
+          resolve(handleError(error, this, timeout, args, latency, resolve, reject));
         }, this.options.timeout);
@@ -297,23 +308,25 @@
           ? result
-          : this.Promise.resolve(result);
+          : Promise.resolve(result);
 
-        promise
-          .then((result) => {
-            if (!timeoutError) {
-              /**
-               * Emitted when the circuit breaker action succeeds
-               * @event CircuitBreaker#success
-               */
-              this.emit('success', result);
-              resolve(result);
-              if (this.options.cache) {
-                CACHE.set(this, promise);
-              }
-              clearTimeout(timeout);
+        promise.then((result) => {
+          if (!timeoutError) {
+            clearTimeout(timeout);
+            /**
+             * Emitted when the circuit breaker action succeeds
+             * @event CircuitBreaker#success
+             */
+            this.emit('success', result, (Date.now() - latencyStartTime));
+            resolve(result);
+            if (this.options.cache) {
+              CACHE.set(this, promise);
             }
-          })
-          .catch((error) =>
-            handleError(error, this, timeout, args, resolve, reject));
+          }
+        })
+        .catch((error) => {
+          const latencyEndTime = Date.now() - latencyStartTime;
+          handleError(error, this, timeout, args, latencyEndTime, resolve, reject);
+        });
       } catch (error) {
-        handleError(error, this, timeout, args, resolve, reject);
+        const latency = Date.now() - latencyStartTime;
+        handleError(error, this, timeout, args, latency, resolve, reject);
       }
@@ -331,6 +344,6 @@ });
 
-function handleError (error, circuit, timeout, args, resolve, reject) {
+function handleError (error, circuit, timeout, args, latency, resolve, reject) {
   clearTimeout(timeout);
-  fail(circuit, error, args);
-  const fb = fallback(circuit, error, args);
+  fail(circuit, error, args, latency);
+  const fb = fallback(circuit, error, args, latency);
   if (fb) resolve(fb);
@@ -342,3 +355,3 @@ else reject(error);
   if (circuit[FALLBACK_FUNCTION]) {
-    return new circuit.Promise((resolve, reject) => {
+    return new Promise((resolve, reject) => {
       const result = circuit[FALLBACK_FUNCTION].apply(circuit[FALLBACK_FUNCTION], args);
@@ -355,3 +368,3 @@ /**
 
-function fail (circuit, err, args) {
+function fail (circuit, err, args, latency) {
   /**
@@ -361,3 +374,3 @@ * Emitted when the circuit breaker action fails
    */
-  circuit.emit('failure', err);
+  circuit.emit('failure', err, latency);
 
@@ -371,4 +384,2 @@ // check stats to see if the circuit should be opened
   }
-
-  return circuit.Promise.reject.apply(null, [err]);
 }
@@ -375,0 +386,0 @@

lib/hystrix-formatter.js

@@ -34,16 +34,27 @@ 'use strict';
   // TODO: caluclate these latency values
-  json.latencyExecute_mean = 0;
+  json.latencyExecute_mean = stats.latencyMean || 0;
   json.latencyExecute = {
-    '0': 0,
-    '25': 0,
-    '50': 0,
-    '75': 0,
-    '90': 0,
-    '95': 0,
-    '99': 0,
-    '99.5': 0,
-    '100': 0
+    0: stats.percentiles['0'],
+    25: stats.percentiles['0.25'],
+    50: stats.percentiles['0.5'],
+    75: stats.percentiles['0.75'],
+    90: stats.percentiles['0.9'],
+    95: stats.percentiles['0.95'],
+    99: stats.percentiles['0.99'],
+    99.5: stats.percentiles['0.995'],
+    100: stats.percentiles['1']
   };
-  json.latencyTotal_mean = 0;
-  json.latencyTotal = { '0': 0, '25': 0, '50': 0, '75': 0, '90': 0, '95': 0, '99': 0, '99.5': 0, '100': 0 };
+  // Whats the difference between execute and total?
+  json.latencyTotal_mean = stats.latencyMean;
+  json.latencyTotal = {
+    0: stats.percentiles['0'],
+    25: stats.percentiles['0.25'],
+    50: stats.percentiles['0.5'],
+    75: stats.percentiles['0.75'],
+    90: stats.percentiles['0.9'],
+    95: stats.percentiles['0.95'],
+    99: stats.percentiles['0.99'],
+    99.5: stats.percentiles['0.995'],
+    100: stats.percentiles['1']
+  };
   json.propertyValue_circuitBreakerRequestVolumeThreshold = 5;
@@ -50,0 +61,0 @@ json.propertyValue_circuitBreakerSleepWindowInMilliseconds = stats.options.resetTimeout;

lib/promisify.js

 'use strict';
 
-const Fidelity = require('fidelity');
-
 module.exports = exports = function promisify (func) {
   return function promisifiedFunction () {
-    return new Fidelity((resolve, reject) => {
+    return new Promise((resolve, reject) => {
       const cb = (err, result) => {
@@ -9,0 +7,0 @@ if (err) reject(err);

lib/status.js

@@ -6,2 +6,3 @@ 'use strict';
 const TIMEOUT = Symbol('timeout');
+const PERCENTILES = Symbol('percentiles');
 
@@ -64,3 +65,7 @@ const EventEmitter = require('events').EventEmitter;
     this[WINDOW] = new Array(this[BUCKETS]);
+    this[PERCENTILES] = [0.0, 0.25, 0.5, 0.75, 0.9, 0.95, 0.99, 0.995, 1];
 
+    // Default this value to true
+    this.rollingPercentilesEnabled = options.rollingPercentilesEnabled;
+
     // prime the window with buckets
@@ -86,8 +91,41 @@ for (let i = 0; i < this[BUCKETS]; i++) this[WINDOW][i] = bucket();
   get stats () {
-    return this[WINDOW].reduce((acc, val) => {
+    const totals = this[WINDOW].reduce((acc, val) => {
       // the window starts with all but one bucket undefined
       if (!val) return acc;
-      Object.keys(acc).forEach(key => (acc[key] += val[key] || 0));
+      Object.keys(acc).forEach(key => {
+        if (key !== 'latencyTimes' && key !== 'percentiles') {
+          (acc[key] += val[key] || 0);
+        }
+      });
+
+      if (this.rollingPercentilesEnabled) {
+        acc.latencyTimes.push.apply(acc.latencyTimes, val.latencyTimes || []);
+      }
       return acc;
     }, bucket());
+
+    if (this.rollingPercentilesEnabled) {
+      // Sort the latencyTimess
+      totals.latencyTimes.sort((a, b) => a - b);
+
+      // Get the mean latency
+      // Mean = sum of all values in the array/length of array
+      if (totals.latencyTimes.length) {
+        totals.latencyMean = (totals.latencyTimes.reduce((a, b) => a + b, 0)) / totals.latencyTimes.length;
+      } else {
+        totals.latencyMean = 0;
+      }
+
+      // Calculate Percentiles
+      this[PERCENTILES].forEach(percentile => {
+        totals.percentiles[percentile] = calculatePercentile(percentile, totals.latencyTimes);
+      });
+    } else {
+      totals.latencyMean = -1;
+      this[PERCENTILES].forEach(percentile => {
+        totals.percentiles[percentile] = -1;
+      });
+    }
+
+    return totals;
   }
@@ -102,4 +140,7 @@
 
-  increment (property) {
+  increment (property, latencyRunTime) {
     this[WINDOW][0][property]++;
+    if (property === 'successes' || property === 'failures' || property === 'timeouts') {
+      this[WINDOW][0].latencyTimes.push(latencyRunTime || 0);
+    }
   }
@@ -129,5 +170,15 @@
   cacheHits: 0,
-  cacheMisses: 0
+  cacheMisses: 0,
+  percentiles: {},
+  latencyTimes: []
 });
 
+function calculatePercentile (percentile, arr) {
+  if (percentile === 0) {
+    return arr[0] || 0;
+  }
+  const idx = Math.ceil(percentile * arr.length);
+  return arr[idx - 1] || 0;
+}
+
 module.exports = exports = Status;

package.json

 {
   "name": "opossum",
-  "version": "1.0.0",
+  "version": "1.1.0",
   "author": "Red Hat, Inc.",
@@ -46,14 +46,16 @@ "license": "Apache-2.0",
     "babel-plugin-transform-mangle-names": "~2.1.2",
-    "babel-plugin-transform-merge-sibling-variables": "6.8.2",
+    "babel-plugin-transform-merge-sibling-variables": "6.8.3",
     "babel-plugin-transform-minify-booleans": "~6.8.0",
     "babel-plugin-transform-undefined-to-void": "~6.8.0",
-    "browserify": "~14.1.0",
+    "browserify": "~14.3.0",
     "escompress": "~0.5.0",
     "eslint": "~3.19.0",
-    "eslint-config-semistandard": "~7.0.0",
-    "eslint-config-standard": "~7.0.0",
-    "eslint-plugin-react": "~6.10.0",
+    "eslint-config-semistandard": "~11.0.0",
+    "eslint-config-standard": "~10.2.0",
+    "eslint-plugin-import": "^2.2.0",
+    "eslint-plugin-node": "^5.0.0",
     "eslint-plugin-promise": "~3.5.0",
-    "eslint-plugin-standard": "~2.1.0",
-    "http-server": "~0.9.0",
+    "eslint-plugin-react": "~7.0.0",
+    "eslint-plugin-standard": "~3.0.1",
+    "http-server": "~0.10.0",
     "ink-docstrap": "~1.3.0",
@@ -75,5 +77,3 @@ "istanbul": "~0.4.5",
   ],
-  "dependencies": {
-    "fidelity": "~4.2.0"
-  }
+  "dependencies": {}
 }

README.md

@@ -23,3 +23,3 @@ # opossum
 | Issue tracker:  | https://github.com/bucharest-gold/opossum/issues  |
-| Engines:        | Node.js 4.x, 5.x, 6.x, 7.x
+| Engines:        | Node.js 4.x, 6.x, 8.x
 
@@ -222,16 +222,2 @@ ## Usage
 
-### Promise Interoperability
-
-The `Promise` implementation used in `opossum` is compliant with both the
-ES6 `Promise` API as well as the `promises/A+` API. This means that it doesn't
-matter what flavor of promise your API uses, `opossum` should work fine with
-it. If you would like to control what `Promise` implementation used in
-`opossum`, provide a `Promise` constructor function in your options when
-you create the breaker. E.g.
-
-```javascript
-// Force opossum to use native JS promises
-const breaker = circuitBreaker(readFile, { Promise: Promise });
-```
-
 ### Hystrix Metrics
@@ -238,0 +224,0 @@

New alerts

License Policy Violation

License

This package is not allowed per your license policy. Review the package's license to ensure compliance.

Found 1 instance in 1 package

Fixed alerts

License Policy Violation

License

This package is not allowed per your license policy. Review the package's license to ensure compliance.

Found 1 instance in 1 package

Major refactor

Supply chain risk

Package has recently undergone a major refactor. It may be unstable or indicate significant internal changes. Use caution when updating to versions that include significant changes.

Found 1 instance in 1 package

Uses eval

Supply chain risk

Package uses dynamic code execution (e.g., eval()), which is a dangerous practice. This can prevent the code from running in certain environments and increases the risk that the code may contain exploits or malicious behavior.

Found 1 instance in 1 package

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

Improved metrics

Dependency count

0

decreased by-100%

Number of low supply chain risk alerts

5

decreased by-44.44%

Number of medium supply chain risk alerts

0

decreased by-100%

Worsened metrics

Total package byte prevSize

298946

decreased by-1.61%

Dev dependency count

26

increased by8.33%

Lines of code

6026

decreased by-2.19%

Number of lines in readme file

228

decreased by-5.79%

Dependency changes

• - Removedfidelity@~4.2.0

• - Removedfidelity@4.2.0(transitive)