feat: request and reply reference type encapsulated

docs/Reference/Warnings.md

@@ -9,7 +9,6 @@
     - [FSTWRN002](#FSTWRN002)
   - [Fastify Deprecation Codes](#fastify-deprecation-codes)
     - [FSTDEP005](#FSTDEP005)
-    - [FSTDEP006](#FSTDEP006)
     - [FSTDEP007](#FSTDEP007)
     - [FSTDEP008](#FSTDEP008)
     - [FSTDEP009](#FSTDEP009)
@@ -73,7 +72,6 @@ Deprecation codes are further supported by the Node.js CLI options:
 | Code | Description | How to solve | Discussion |
 | ---- | ----------- | ------------ | ---------- |
 | <a id="FSTDEP005">FSTDEP005</a> | You are accessing the deprecated `request.connection` property. | Use `request.socket`. | [#2594](https://github.com/fastify/fastify/pull/2594) |
-| <a id="FSTDEP006">FSTDEP006</a> | You are decorating Request/Reply with a reference type. This reference is shared amongst all requests. | Do not use Arrays/Objects as values when decorating Request/Reply. | [#2688](https://github.com/fastify/fastify/pull/2688) |
 | <a id="FSTDEP007">FSTDEP007</a> | You are trying to set a HEAD route using `exposeHeadRoute` route flag when a sibling route is already set. | Remove `exposeHeadRoutes` or explicitly set `exposeHeadRoutes` to `false` | [#2700](https://github.com/fastify/fastify/pull/2700) |
 | <a id="FSTDEP008">FSTDEP008</a> | You are using route constraints via the route `{version: "..."}` option.  |  Use `{constraints: {version: "..."}}` option.  | [#2682](https://github.com/fastify/fastify/pull/2682) |
 | <a id="FSTDEP009">FSTDEP009</a> | You are using a custom route versioning strategy via the server `{versioning: "..."}` option. |  Use `{constraints: {version: "..."}}` option.  | [#2682](https://github.com/fastify/fastify/pull/2682) |

lib/decorate.js

@@ -1,5 +1,7 @@
 'use strict'
 
+const deepClone = require('rfdc')({ circles: true, proto: false })
+
 /* eslint no-prototype-builtins: 0 */
 
 const {
@@ -16,8 +18,6 @@ const {
   FST_ERR_DEC_DEPENDENCY_INVALID_TYPE
 } = require('./errors')
 
-const { FSTDEP006 } = require('./warnings')
-
 function decorate (instance, name, fn, dependencies) {
   if (Object.prototype.hasOwnProperty.call(instance, name)) {
     throw new FST_ERR_DEC_ALREADY_PRESENT(name)
@@ -56,9 +56,19 @@ function decorateConstructor (konstructor, name, fn, dependencies) {
   }
 }
 
-function checkReferenceType (name, fn) {
+function encapsulateReferenceType (name, fn) {
   if (typeof fn === 'object' && fn && !(typeof fn.getter === 'function' || typeof fn.setter === 'function')) {
-    FSTDEP006(name)
+    return encapsulatedDecorator(fn)
+  }
+
+  return fn
+}
+
+function encapsulatedDecorator (originalValue) {
+  return {
+    getter: function getter () {
+      return deepClone(originalValue)
+    }
   }
 }
 
@@ -112,15 +122,15 @@ function checkDependencies (instance, name, deps) {
 
 function decorateReply (name, fn, dependencies) {
   assertNotStarted(this, name)
-  checkReferenceType(name, fn)
-  decorateConstructor(this[kReply], name, fn, dependencies)
+  const decorator = encapsulateReferenceType(name, fn)
+  decorateConstructor(this[kReply], name, decorator, dependencies)
   return this
 }
 
 function decorateRequest (name, fn, dependencies) {
   assertNotStarted(this, name)
-  checkReferenceType(name, fn)
-  decorateConstructor(this[kRequest], name, fn, dependencies)
+  const decorator = encapsulateReferenceType(name, fn)
+  decorateConstructor(this[kRequest], name, decorator, dependencies)
   return this
 }
 

lib/warnings.js

@@ -5,7 +5,6 @@ const { createDeprecation, createWarning } = require('process-warning')
 /**
  * Deprecation codes:
  *   - FSTDEP005
- *   - FSTDEP006
  *   - FSTDEP007
  *   - FSTDEP008
  *   - FSTDEP009
@@ -26,11 +25,6 @@ const FSTDEP005 = createDeprecation({
   message: 'You are accessing the deprecated "request.connection" property. Use "request.socket" instead.'
 })
 
-const FSTDEP006 = createDeprecation({
-  code: 'FSTDEP006',
-  message: 'You are decorating Request/Reply with a reference type. This reference is shared amongst all requests. Use onRequest hook instead. Property: %s'
-})
-
 const FSTDEP007 = createDeprecation({
   code: 'FSTDEP007',
   message: 'You are trying to set a HEAD route using "exposeHeadRoute" route flag when a sibling route is already set. See documentation for more info.'
@@ -107,7 +101,6 @@ const FSTSEC001 = createWarning({
 
 module.exports = {
   FSTDEP005,
-  FSTDEP006,
   FSTDEP007,
   FSTDEP008,
   FSTDEP009,

test/decorator.test.js

@@ -789,36 +789,64 @@ test('decorate* should throw if called after ready', async t => {
   await fastify.close()
 })
 
-test('decorate* should emit warning if an array is passed', t => {
-  t.plan(1)
+test('decorate* should encapsulate the value if an array is passed', async t => {
+  t.plan(6)
 
-  function onWarning (name) {
-    t.equal(name, 'test_array')
-  }
+  const fastify = Fastify()
+  fastify.decorateRequest('test_array', [])
+  fastify.decorateReply('test_array', [])
 
-  const decorate = proxyquire('../lib/decorate', {
-    './warnings': {
-      FSTDEP006: onWarning
-    }
+  fastify.get('/', async function (req, reply) {
+    t.same(req.test_array, [])
+    t.same(reply.test_array, [])
+
+    req.test_array.push(1)
+    reply.test_array.push(2)
   })
-  const fastify = proxyquire('..', { './lib/decorate.js': decorate })()
-  fastify.decorateRequest('test_array', [])
+
+  await fastify.inject('/')
+  await fastify.inject('/')
+  await fastify.inject('/')
 })
 
-test('decorate* should emit warning if object type is passed', t => {
-  t.plan(1)
+test('decorate* should encapsulate the value if an array is passed (deep clone)', async t => {
+  t.plan(6)
 
-  function onWarning (name) {
-    t.equal(name, 'test_object')
-  }
+  const fastify = Fastify()
+  fastify.decorateRequest('test_array', [{ a: { b: { c: 1 } } }])
+  fastify.decorateReply('test_array', [{ a: { b: { c: 1 } } }])
 
-  const decorate = proxyquire('../lib/decorate', {
-    './warnings': {
-      FSTDEP006: onWarning
-    }
+  fastify.get('/', async function (req, reply) {
+    t.same(req.test_array, [{ a: { b: { c: 1 } } }])
+    t.same(reply.test_array, [{ a: { b: { c: 1 } } }])
+
+    req.test_array[0].a.b.c = 99
+    reply.test_array[0].a.b.c = 99
   })
-  const fastify = proxyquire('..', { './lib/decorate.js': decorate })()
+
+  await fastify.inject('/')
+  await fastify.inject('/')
+  await fastify.inject('/')
+})
+
+test('decorate* should encapsulate the value if object type is passed', { only: true }, async t => {
+  t.plan(6)
+
+  const fastify = Fastify()
   fastify.decorateRequest('test_object', { foo: 'bar' })
+  fastify.decorateReply('test_object', { foo: 'bar' })
+
+  fastify.get('/', async function (req, reply) {
+    t.same(req.test_object, { foo: 'bar' })
+    t.same(reply.test_object, { foo: 'bar' })
+
+    req.test_object.user = 'user'
+    reply.test_array.user = 'user'
+  })
+
+  await fastify.inject('/')
+  await fastify.inject('/')
+  await fastify.inject('/')
 })
 
 test('decorate* should not emit warning if object with getter/setter is passed', t => {