feat(instrumentations): possibility to disable them

Author: gergelyke

README.md

@@ -63,6 +63,9 @@ module.exports = {
   ],
   ignoreOutgoingHosts: [
     'google.com'
+  ],
+  disableInstrumentations: [
+    'mongodb'
   ]
 }
 ```

lib/index.js

@@ -36,7 +36,8 @@ function Trace () {
   })
 
   Instrumentation.create({
-    agent: this.agent
+    agent: this.agent,
+    config: this.config
   })
 }
 

lib/index.spec.js

@@ -45,7 +45,8 @@ describe('The trace module', function () {
       config: fakeConfig
     })
     expect(instrumentationCreateStub).to.be.calledWith({
-      agent: fakeAgent
+      agent: fakeAgent,
+      config: fakeConfig
     })
     expect(configCreateStub).to.be.calledOnce
   })

lib/instrumentations/index.js

@@ -1,6 +1,7 @@
 var Module = require('module')
 var path = require('path')
 var fs = require('fs')
+var remove = require('lodash.remove')
 var debug = require('debug')('risingstack/trace:instrumentations')
 
 var shimmer = require('../utils/shimmer')
@@ -81,6 +82,16 @@ module.exports.create = function (options) {
     }
   })
 
+  options.config.disableInstrumentations.forEach(function (instrumentation) {
+    remove(INSTRUMENTED_LIBS, function (lib) {
+      return instrumentation === lib
+    })
+
+    remove(CORE_LIBS, function (lib) {
+      return instrumentation === lib
+    })
+  })
+
   CORE_LIBS.forEach(function (core) {
     var fileName = core + '.js'
     var filePath = path.join(__dirname, 'core', fileName)
@@ -93,3 +104,6 @@ module.exports.create = function (options) {
     }
   })
 }
+
+module.exports.INSTRUMENTED_LIBS = INSTRUMENTED_LIBS
+module.exports.CORE_LIBS = CORE_LIBS

lib/instrumentations/index.spec.js

@@ -0,0 +1,18 @@
+var expect = require('chai').expect
+var instrumentor = require('./index')
+var Shimmer = require('../utils/shimmer')
+
+describe('The instrumentor module', function () {
+  it('can be created', function () {
+    var shimmerStub = this.sandbox.stub(Shimmer, 'wrap')
+
+    instrumentor.create({
+      config: {
+        disableInstrumentations: ['mongodb', 'http']
+      }
+    })
+
+    expect(instrumentor.CORE_LIBS.indexOf('http')).to.eql(-1)
+    expect(instrumentor.INSTRUMENTED_LIBS.indexOf('mongodb')).to.eql(-1)
+  })
+})

lib/utils/configReader.js

@@ -57,7 +57,10 @@ ConfigReader.prototype._getEnvVarConfig = function () {
     collectorLanguage: process.env.TRACE_COLLECTOR_LANGUAGE,
     serviceName: process.env.TRACE_SERVICE_NAME,
     configPath: process.env.TRACE_CONFIG_PATH,
-    apiKey: process.env.TRACE_API_KEY
+    apiKey: process.env.TRACE_API_KEY,
+    disableInstrumentations: process.env.TRACE_DISABLE_INSTRUMENTATIONS
+      ? process.env.TRACE_DISABLE_INSTRUMENTATIONS.split(',')
+      : []
   }
 
   var ignoreHeaders

package.json

@@ -47,6 +47,7 @@
     "lodash.defaults": "4.0.1",
     "lodash.flatmap": "4.3.0",
     "lodash.isnumber": "3.0.3",
+    "lodash.remove": "4.5.0",
     "node-uuid": "1.4.7",
     "qs": "6.2.0",
     "semver": "5.1.0",