standardize a way to configure feature toggles

api/v1/helpers/nouns/perspectives.js

@@ -12,15 +12,8 @@
 'use strict'; // eslint-disable-line strict
 
 const Perspective = require('../../../../db/index').Perspective;
-const config = require('../../../../config');
-
+const featureToggles = require('feature-toggles');
 const m = 'perspective';
-let cacheEnabled = false;
-
-if (config.enableCachePerspective === 'true' ||
- config.enableCachePerspective === true) {
-  cacheEnabled = true;
-}
 
 module.exports = {
   apiLinks: {
@@ -36,5 +29,5 @@ module.exports = {
   },
   model: Perspective,
   modelName: 'Perspective',
-  cacheEnabled,
+  cacheEnabled: featureToggles.isFeatureEnabled('enableCachePerspective'),
 }; // exports

api/v1/helpers/verbs/findUtils.js

@@ -10,14 +10,11 @@
  * api/v1/helpers/verbs/findUtils.js
  */
 'use strict';
-
+const featureToggles = require('feature-toggles');
 const u = require('./utils');
 const constants = require('../../constants');
 const defaults = require('../../../../config').api.defaults;
-const conf = require('../../../../config');
-
-const env = conf.environment[conf.nodeEnv];
-const filterSubjByTags = env.filterSubjByTags;
+const filterSubjByTags = featureToggles.isFeatureEnabled('filterSubjByTags');
 
 /**
  * Escapes all percent literals so they're not treated as wildcards.

clock/index.js

@@ -13,12 +13,12 @@
  * use "npm run start-clock". To start both the web and the clock process
  * locally, use "heroku local"
  */
+const featureToggles = require('feature-toggles');
 const conf = require('../config');
 const env = conf.environment[conf.nodeEnv];
 
 const dbSample = require('../db/index').Sample;
 
-if (conf.enableClockDyno) {
+if (featureToggles.isFeatureEnabled('enableClockDyno')) {
   setInterval(() => dbSample.doTimeout(), env.checkTimeoutIntervalMillis);
 }
-

config.js

@@ -12,7 +12,7 @@
  * Configuration Settings
  */
 'use strict'; // eslint-disable-line strict
-
+require('./config/toggles'); // Loads the feature toggles
 const configUtil = require('./config/configUtil');
 const defaultPort = 3000;
 const defaultPostgresPort = 5432;
@@ -39,23 +39,12 @@ const iplist = configUtil.parseIPlist(ipWhitelist);
 
 // Check for timed-out samples every 30 seconds if not specified in env var
 const DEFAULT_CHECK_TIMEOUT_INTERVAL_MILLIS = 30000;
-const enableClockDyno = pe.HEROKU_CLOCK_DYNO === 'true' ||
-                            pe.HEROKU_CLOCK_DYNO === true || false;
 
 // audit level values can be one of these: API, DB, ALL, NONE
 const auditSubjects = pe.AUDIT_SUBJECTS || 'NONE';
 const auditSamples = pe.AUDIT_SAMPLES || 'NONE';
 const auditAspects = pe.AUDIT_ASPECTS || 'NONE';
 
-const optimizeUpsert = pe.OPTIMIZE_UPSERT === 'true' ||
- pe.OPTIMIZE_UPSERT === true || false;
-
-// env variable to enable caching for /GET /v1/perspectives/{key}
-const enableCachePerspective = pe.ENABLE_CACHE_PERSPECTIVE || false;
-
-const filterSubjByTags = pe.FILTER_SUBJ_BY_TAGS === 'true' ||
- pe.FILTER_SUBJ_BY_TAGS === true || false;
-
 module.exports = {
 
   api: {
@@ -114,7 +103,6 @@ module.exports = {
       useAccessToken: pe.USE_ACCESS_TOKEN || false,
       tokenSecret:
        '7265666f637573726f636b7377697468677265656e6f776c7373616e6672616e',
-      filterSubjByTags,
     },
     development: {
       checkTimeoutIntervalMillis: pe.CHECK_TIMEOUT_INTERVAL_MILLIS ||
@@ -134,7 +122,6 @@ module.exports = {
       useAccessToken: pe.USE_ACCESS_TOKEN || false,
       tokenSecret:
        '7265666f637573726f636b7377697468677265656e6f776c7373616e6672616e',
-      filterSubjByTags,
     },
     production: {
       checkTimeoutIntervalMillis: pe.CHECK_TIMEOUT_INTERVAL_MILLIS ||
@@ -153,7 +140,6 @@ module.exports = {
       useAccessToken: pe.USE_ACCESS_TOKEN || false,
       tokenSecret: pe.SECRET_TOKEN ||
        '7265666f637573726f636b7377697468677265656e6f776c7373616e6672616e',
-      filterSubjByTags,
     },
     test: {
       checkTimeoutIntervalMillis: pe.CHECK_TIMEOUT_INTERVAL_MILLIS ||
@@ -172,7 +158,6 @@ module.exports = {
       useAccessToken: pe.USE_ACCESS_TOKEN || false,
       tokenSecret: pe.SECRET_TOKEN ||
        '7265666f637573726f636b7377697468677265656e6f776c7373616e6672616e',
-      filterSubjByTags,
     },
     testDisableHttp: {
       checkTimeoutIntervalMillis: pe.CHECK_TIMEOUT_INTERVAL_MILLIS ||
@@ -186,7 +171,6 @@ module.exports = {
       useAccessToken: 'true',
       tokenSecret:
        '7265666f637573726f636b7377697468677265656e6f776c7373616e6672616e',
-      filterSubjByTags,
     },
     testWhitelistLocalhost: {
       checkTimeoutIntervalMillis: pe.CHECK_TIMEOUT_INTERVAL_MILLIS ||
@@ -200,7 +184,6 @@ module.exports = {
       ipWhitelist: iplist,
       tokenSecret:
        '7265666f637573726f636b7377697468677265656e6f776c7373616e6672616e',
-      filterSubjByTags,
     },
     testBlockAllhosts: {
       checkTimeoutIntervalMillis: pe.CHECK_TIMEOUT_INTERVAL_MILLIS ||
@@ -214,7 +197,6 @@ module.exports = {
       ipWhitelist: [''],
       tokenSecret:
        '7265666f637573726f636b7377697468677265656e6f776c7373616e6672616e',
-      filterSubjByTags,
     },
     testTokenReq: {
       checkTimeoutIntervalMillis: pe.CHECK_TIMEOUT_INTERVAL_MILLIS ||
@@ -228,7 +210,6 @@ module.exports = {
       useAccessToken: 'true',
       tokenSecret:
        '7265666f637573726f636b7377697468677265656e6f776c7373616e6672616e',
-      filterSubjByTags,
     },
     testTokenNotReq: {
       checkTimeoutIntervalMillis: pe.CHECK_TIMEOUT_INTERVAL_MILLIS ||
@@ -242,22 +223,7 @@ module.exports = {
       useAccessToken: false,
       tokenSecret:
        '7265666f637573726f636b7377697468677265656e6f776c7373616e6672616e',
-      filterSubjByTags,
     },
-    testSubjTagFilter: {
-      checkTimeoutIntervalMillis: pe.CHECK_TIMEOUT_INTERVAL_MILLIS ||
-        DEFAULT_CHECK_TIMEOUT_INTERVAL_MILLIS,
-      dbLogging: false, // console.log | false | ...
-      dbUrl: defaultDbUrl,
-      disableHttp,
-      redisUrl: '//127.0.0.1:6379',
-      defaultNodePort: defaultPort,
-      host: '127.0.0.1',
-      useAccessToken: false,
-      tokenSecret:
-       '7265666f637573726f636b7377697468677265656e6f776c7373616e6672616e',
-      filterSubjByTags: true,
-    }
   },
 
   nodeEnv,
@@ -269,7 +235,4 @@ module.exports = {
   auditSubjects,
   auditSamples,
   auditAspects,
-  optimizeUpsert,
-  enableCachePerspective,
-  enableClockDyno,
 };

config/toggles.js

@@ -0,0 +1,61 @@
+/**
+ * Copyright (c) 2016, salesforce.com, inc.
+ * All rights reserved.
+ * Licensed under the BSD 3-Clause license.
+ * For full license text, see LICENSE.txt file in the repo root or
+ * https://opensource.org/licenses/BSD-3-Clause
+ */
+
+/**
+ * /config/toggles.js
+ *
+ * Configure feature toggles.
+ *
+ * Usage: wherever you need to check whether a feature is enabled, just
+ * add require('feature-toggles') to the top of the module then use
+ * featureToggles.isFeatureEnabled('MY_FEATURE_NAME') or
+ * featureToggles.isFeatureEnabled('MY_FEATURE_NAME', 'myarg', 'anotherarg').
+ * (All the args after the feature name are passed to the function if the
+ * feature is defined using a function.)
+ */
+'use strict'; // eslint-disable-line strict
+const featureToggles = require('feature-toggles');
+const pe = process.env; // eslint-disable-line no-process-env
+
+/**
+ * Return boolean true if the named environment variable is boolean true or
+ * case-insensitive string 'true'.
+ *
+ * @param {String} environmentVariableName - The name of the environment var.
+ * @returns {Boolean} true if the named environment variable is boolean true or
+ *  case-insensitive string 'true'.
+ */
+function environmentVariableTrue(processEnv, environmentVariableName) {
+  const x = processEnv[environmentVariableName];
+  return typeof x !== 'undefined' && x !== null &&
+    x.toString().toLowerCase() === 'true';
+} // environmentVariableTrue
+
+/*
+ * Add a new feature flag by adding an attribute here.
+ */
+const toggles = {
+  // Enable caching for GET /v1/perspectives/{key}?
+  enableCachePerspective: environmentVariableTrue(pe,
+    'ENABLE_CACHE_PERSPECTIVE'),
+
+  // Enable heroku clock dyno
+  enableClockDyno: environmentVariableTrue(pe, 'HEROKU_CLOCK_DYNO'),
+
+  // Enable GET /v1/subjects?tags=...
+  filterSubjByTags: environmentVariableTrue(pe, 'FILTER_SUBJ_BY_TAGS'),
+
+  // Enable bulk upsert optimization
+  optimizeUpsert: environmentVariableTrue(pe, 'OPTIMIZE_UPSERT'),
+};
+
+featureToggles.load(toggles);
+
+module.exports = {
+  environmentVariableTrue, // exporting to make it easy to test
+};

db/model/sample.js

@@ -10,6 +10,7 @@
  * db/model/sample.js
  */
 'use strict'; // eslint-disable-line strict
+const featureToggles = require('feature-toggles');
 const constants = require('../constants');
 const u = require('../helpers/sampleUtils');
 const common = require('../helpers/common');
@@ -173,7 +174,7 @@ module.exports = function sample(seq, dataTypes) {
        *  encountered while performing the sample upsert operation itself.
        */
       upsertByName(toUpsert, isBulk) {
-        if (config.optimizeUpsert) {
+        if (featureToggles.isFeatureEnabled('optimizeUpsert')) {
           let sampleExists = true;
           return new seq.Promise((resolve, reject) => {
             // get sample by name
@@ -219,39 +220,40 @@ module.exports = function sample(seq, dataTypes) {
               isBulk ? resolve(err) : reject(err);
             });
           });
-        } else {
-          let subjasp;
-          return new seq.Promise((resolve, reject) => {
-            u.getSubjectAndAspectBySampleName(seq, toUpsert.name, isBulk)
-            .then((sa) => {
-              subjasp = sa;
-              toUpsert.subjectId = sa.subject.id;
-              toUpsert.aspectId = sa.aspect.id;
-            })
-            .then(() => Sample.findOne({
-              where: {
-                subjectId: subjasp.subject.id,
-                aspectId: subjasp.aspect.id,
-                isDeleted: NO,
-              },
-            }))
-            .then((o) => {
-              if (o === null) {
-                return Sample.create(toUpsert);
-              }
+        }
 
-              // set value changed to true, during updates to avoid timeouts
-              // Adding this to the before update hook does
-              // give the needed effect; so adding it here!!!.
-              o.changed('value', true);
-              return o.update(toUpsert);
-            })
-            .then((o) => resolve(o))
-            .catch((err) => {
-              isBulk ? resolve(err) : reject(err);
-            });
+        // 'optimizeUpsert' is not enabled
+        let subjasp;
+        return new seq.Promise((resolve, reject) => {
+          u.getSubjectAndAspectBySampleName(seq, toUpsert.name, isBulk)
+          .then((sa) => {
+            subjasp = sa;
+            toUpsert.subjectId = sa.subject.id;
+            toUpsert.aspectId = sa.aspect.id;
+          })
+          .then(() => Sample.findOne({
+            where: {
+              subjectId: subjasp.subject.id,
+              aspectId: subjasp.aspect.id,
+              isDeleted: NO,
+            },
+          }))
+          .then((o) => {
+            if (o === null) {
+              return Sample.create(toUpsert);
+            }
+
+            // set value changed to true, during updates to avoid timeouts
+            // Adding this to the before update hook does
+            // give the needed effect; so adding it here!!!.
+            o.changed('value', true);
+            return o.update(toUpsert);
+          })
+          .then((o) => resolve(o))
+          .catch((err) => {
+            isBulk ? resolve(err) : reject(err);
           });
-        }
+        });
       }, // upsertByName
 
       bulkUpsertByName(toUpsert) {

index.js

@@ -9,7 +9,7 @@
 /**
  * ./index.js
  *
- * Main module to start the express server(web process). To just start the
+ * Main module to start the express server (web process). To just start the
  * web process use "node index.js". To start both the web and the clock process
  * use "heroku local"
  */
@@ -20,6 +20,7 @@ const WORKERS = process.env.WEB_CONCURRENCY || 1;
  * Entry point for each newly clustered process
  */
 function start() { // eslint-disable-line max-statements
+  const featureToggles = require('feature-toggles');
   const conf = require('./config');
 
   /*
@@ -123,11 +124,12 @@ function start() { // eslint-disable-line max-statements
   }
 
   // if the clock dyno is not enabled run the Sample timeout query here.
-  if (!conf.enableClockDyno) {
+  if (!featureToggles.isFeatureEnabled('enableClockDyno')) {
     // require the sample model only if we want to run the timeout query here
     const dbSample = require('./db/index').Sample;
     setInterval(() => dbSample.doTimeout(), env.checkTimeoutIntervalMillis);
   }
+
   // View engine setup
   app.set('views', path.join(__dirname, 'view'));
   app.set('view engine', 'pug');

package.json

@@ -34,9 +34,9 @@
     "test-token-notreq": "NODE_ENV=testTokenNotReq mocha -R dot --recursive tests/tokenNotReq",
     "test-db": "npm run resetdb && mocha -R dot --recursive tests/db",
     "test-realtime": "mocha -R dot --recursive tests/realtime",
-    "test-subj-tag-filter": "NODE_ENV=testSubjTagFilter mocha -R dot --recursive tests/subjectTagFilter",
+    "test-subj-tag-filter": "FILTER_SUBJ_BY_TAGS=true mocha -R dot --recursive tests/subjectTagFilter",
     "test-view": "NODE_ENV=test mocha -R dot --recursive --compilers js:babel-core/register --require ./tests/view/setup.js tests/view",
-    "test": "istanbul cover ./node_modules/mocha/bin/_mocha --report lcovonly -- -R dot --recursive tests/api tests/db && cat ./coverage/lcov.info | ./node_modules/coveralls/bin/coveralls.js && rm -rf ./coverage && npm run test-view && npm run test-realtime && npm run test-token-req && npm run test-token-notreq && npm run test-disablehttp && npm run test-subj-tag-filter",
+    "test": "istanbul cover ./node_modules/mocha/bin/_mocha --report lcovonly -- -R dot --recursive tests/api tests/db tests/config && cat ./coverage/lcov.info | ./node_modules/coveralls/bin/coveralls.js && rm -rf ./coverage && npm run test-view && npm run test-realtime && npm run test-token-req && npm run test-token-notreq && npm run test-disablehttp && npm run test-subj-tag-filter",
     "postinstall": "NODE_ENV=production gulp browserifyViews && gulp movecss && gulp movesocket && gulp movelensutil && npm run checkdb",
     "prestart": "npm run checkprivatedb"
   },
@@ -72,6 +72,7 @@
     "express-ipfilter": "^0.0.24",
     "express-session": "^1.13.0",
     "extract-text-webpack-plugin": "^0.8.2",
+    "feature-toggles": "^1.4.0",
     "fs": "0.0.2",
     "gulp": "^3.9.0",
     "gulp-chmod": "^1.3.0",
@@ -87,6 +88,7 @@
     "multer": "^1.0.3",
     "newrelic": "^1.28.1",
     "nock": "^3.6.0",
+    "npm": "^3.10.9",
     "npm-watch": "^0.1.3",
     "passport": "^0.3.2",
     "passport-local": "^1.0.0",