chore: Removed repetitive cache busting (#2160)

Author: jsumners-nr

test/lib/agent_helper.js

@@ -17,6 +17,7 @@ const { EventEmitter } = require('events')
 const Transaction = require('../../lib/transaction')
 const symbols = require('../../lib/symbols')
 const InstrumentationTracker = require('../../lib/instrumentation-tracker')
+const { removeModules } = require('./cache-buster')
 const http = require('http')
 const https = require('https')
 const semver = require('semver')
@@ -220,11 +221,7 @@ helper.maybeLoadSecurityAgent = function maybeLoadSecurityAgent(agent) {
  */
 helper.maybeUnloadSecurityAgent = function maybeUnloadSecurityAgent(agent) {
   if (helper.isSecurityAgentEnabled(agent)) {
-    Object.keys(require.cache).forEach((key) => {
-      if (key.includes('@newrelic/security-agent')) {
-        delete require.cache[key]
-      }
-    })
+    removeModules(['@newrelic/security-agent'])
   }
 }
 

test/lib/cache-buster.js

@@ -0,0 +1,55 @@
+/*
+ * Copyright 2024 New Relic Corporation. All rights reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+'use strict'
+
+/**
+ * Utility method to remove a set of modules from the require cache.
+ *
+ * @param {string[]} modules The set of module names to remove from the cache.
+ */
+module.exports = {
+  /**
+   * Removes explicitly named modules from the require cache.
+   *
+   * @param {string[]} modules
+   *
+   * @returns {number} The number of cache entries removed.
+   */
+  removeModules(modules = []) {
+    let removed = 0
+    const keys = Object.keys(require.cache)
+    for (const mod of modules) {
+      for (const key of keys) {
+        if (key.includes(mod) === false) {
+          continue
+        }
+        delete require.cache[key]
+        removed += 1
+      }
+    }
+    return removed
+  },
+
+  /**
+   * Removes modules from the require cache that are identified by a matcher.
+   *
+   * @param {RegExp} matcher
+   *
+   * @returns {number} The number of cache entries removed.
+   */
+  removeMatchedModules(matcher) {
+    let removed = 0
+    const keys = Object.keys(require.cache)
+    for (const key of keys) {
+      if (matcher.test(key) === false) {
+        continue
+      }
+      delete require.cache[key]
+      removed += 1
+    }
+    return removed
+  }
+}

test/unit/config/config-location.test.js

@@ -11,6 +11,7 @@ const fs = require('fs')
 const fsPromises = require('fs/promises')
 const sinon = require('sinon')
 
+const { removeMatchedModules } = require('../../lib/cache-buster')
 const Config = require('../../../lib/config')
 
 tap.test('when overriding the config file location via NEW_RELIC_HOME', (t) => {
@@ -153,11 +154,7 @@ tap.test('Selecting config file path', (t) => {
     process.chdir(originalWorkingDirectory)
 
     const mainModuleRegex = new RegExp(MAIN_MODULE_DIR)
-    Object.keys(require.cache).forEach((key) => {
-      if (mainModuleRegex.test(key)) {
-        delete require.cache[key]
-      }
-    })
+    removeMatchedModules(mainModuleRegex)
   })
 
   t.test('should load the default newrelic.js config file', (t) => {

test/unit/instrumentation/koa/koa.test.js

@@ -7,6 +7,7 @@
 
 const tap = require('tap')
 const helper = require('../../../lib/agent_helper')
+const { removeModules } = require('../../../lib/cache-buster')
 const InstrumentationDescriptor = require('../../../../lib/instrumentation-descriptor')
 
 tap.beforeEach((t) => {
@@ -23,11 +24,7 @@ tap.beforeEach((t) => {
 
 tap.afterEach((t) => {
   helper.unloadAgent(t.context.agent)
-  Object.keys(require.cache).forEach((key) => {
-    if (key.includes('koa')) {
-      delete require.cache[key]
-    }
-  })
+  removeModules(['koa'])
 })
 
 tap.test('Koa instrumentation', async (t) => {

test/unit/instrumentation/koa/route.test.js

@@ -8,6 +8,7 @@
 const tap = require('tap')
 const { METHODS } = require('../../../../lib/instrumentation/http-methods')
 const helper = require('../../../lib/agent_helper')
+const { removeModules } = require('../../../lib/cache-buster')
 const InstrumentationDescriptor = require('../../../../lib/instrumentation-descriptor')
 
 tap.beforeEach((t) => {
@@ -24,11 +25,7 @@ tap.beforeEach((t) => {
 
 tap.afterEach((t) => {
   helper.unloadAgent(t.context.agent)
-  Object.keys(require.cache).forEach((key) => {
-    if (key.includes('koa-route')) {
-      delete require.cache[key]
-    }
-  })
+  removeModules(['koa-route'])
 })
 
 tap.test('methods', function (t) {

test/unit/instrumentation/koa/router.test.js

@@ -10,6 +10,7 @@ const tap = require('tap')
 const instrumentation = require('../../../../lib/instrumentation/koa/router-instrumentation')
 const { METHODS } = require('../../../../lib/instrumentation/http-methods')
 const helper = require('../../../lib/agent_helper')
+const { removeModules } = require('../../../lib/cache-buster')
 const InstrumentationDescriptor = require('../../../../lib/instrumentation-descriptor')
 const WRAPPED_METHODS = ['param', 'register', 'routes', 'middleware', 'allowedMethods']
 const UNWRAPPED_METHODS = METHODS.concat([
@@ -45,11 +46,7 @@ tap.test('koa-router', (t) => {
 
   t.afterEach((t) => {
     helper.unloadAgent(t.context.agent)
-    Object.keys(require.cache).forEach((key) => {
-      if (key.includes(koaRouterMod)) {
-        delete require.cache[key]
-      }
-    })
+    removeModules([koaRouterMod])
   })
 
   t.test('mounting paramware', async (t) => {
@@ -99,11 +96,7 @@ tap.test('koa-router', (t) => {
 
   t.afterEach((t) => {
     helper.unloadAgent(t.context.agent)
-    Object.keys(require.cache).forEach((key) => {
-      if (key.includes(koaRouterMod)) {
-        delete require.cache[key]
-      }
-    })
+    removeModules([koaRouterMod])
   })
 
   t.test('mounting paramware', async (t) => {

test/versioned/amqplib/callback.tap.js

@@ -8,6 +8,7 @@
 const amqpUtils = require('./amqp-utils')
 const API = require('../../../api')
 const helper = require('../../lib/agent_helper')
+const { removeMatchedModules } = require('../../lib/cache-buster')
 const tap = require('tap')
 
 /*
@@ -64,11 +65,7 @@ tap.test('amqplib callback instrumentation', function (t) {
 
   t.afterEach(function () {
     helper.unloadAgent(agent)
-    Object.keys(require.cache).forEach(function (key) {
-      if (/amqplib/.test(key)) {
-        delete require.cache[key]
-      }
-    })
+    removeMatchedModules(/amqplib/)
 
     if (!conn) {
       return

test/versioned/amqplib/promises.tap.js

@@ -8,6 +8,7 @@
 const amqpUtils = require('./amqp-utils')
 const API = require('../../../api')
 const helper = require('../../lib/agent_helper')
+const { removeMatchedModules } = require('../../lib/cache-buster')
 const tap = require('tap')
 
 /*
@@ -37,11 +38,7 @@ tap.test('amqplib promise instrumentation', function (t) {
     // which the test itself re-requires, but second-order modules (deps of
     // instrumented methods) are not reloaded and thus not re-instrumented. To
     // resolve this we just delete everything. Kill it all.
-    Object.keys(require.cache).forEach(function (key) {
-      if (/amqplib|bluebird/.test(key)) {
-        delete require.cache[key]
-      }
-    })
+    removeMatchedModules(/amqplib|bluebird/)
 
     agent = helper.instrumentMockedAgent({
       attributes: {

test/versioned/bunyan/bunyan.tap.js

@@ -7,6 +7,7 @@
 
 const tap = require('tap')
 const helper = require('../../lib/agent_helper')
+const { removeMatchedModules } = require('../../lib/cache-buster')
 require('../../lib/logging-helper')
 const { LOGGING } = require('../../../lib/metrics/names')
 const { makeSink, logStuff, originalMsgAssertion, logForwardingMsgAssertion } = require('./helpers')
@@ -28,11 +29,7 @@ tap.test('bunyan instrumentation', (t) => {
     bunyan = null
     // must purge require cache of bunyan related instrumentation
     // to ensure it re-registers on subsequent test runs
-    Object.keys(require.cache).forEach((key) => {
-      if (/bunyan/.test(key)) {
-        delete require.cache[key]
-      }
-    })
+    removeMatchedModules(/bunyan/)
   })
 
   t.test('logging disabled', (t) => {

test/versioned/grpc/client-bidi-streaming.tap.js

@@ -7,6 +7,7 @@
 
 const tap = require('tap')
 const helper = require('../../lib/agent_helper')
+const { removeModules } = require('../../lib/cache-buster')
 const { ERR_CODE, ERR_MSG } = require('./constants.cjs')
 
 const {
@@ -41,11 +42,7 @@ tap.test('gRPC Client: Bidi Streaming', (t) => {
     client.close()
     grpc = null
     proto = null
-    Object.keys(require.cache).forEach((key) => {
-      if (key.includes('@grpc/grpc-js')) {
-        delete require.cache[key]
-      }
-    })
+    removeModules(['@grpc/grpc-js'])
   })
 
   t.test(