From 3ddb51b5ef40064fa1ae1b859540d1a9b35021ef Mon Sep 17 00:00:00 2001
From: Simone Busoli <simone.busoli@nearform.com>
Date: Wed, 2 Dec 2020 23:38:34 +0100
Subject: [PATCH 1/2] fix: cache

---
 SerializerManager.js | 9 ++++++++-
 index.js             | 4 ++++
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/SerializerManager.js b/SerializerManager.js
index 892f4b0..306dc19 100644
--- a/SerializerManager.js
+++ b/SerializerManager.js
@@ -14,15 +14,21 @@ class Serializer {
 class SerializerManager {
   constructor (configuration) {
     this.serializers = configuration.serializers
+    this.cache = configuration.cache
   }
 
   findSerializer (types) {
+    const cacheValue = this.cache[types]
+
+    if (cacheValue) return cacheValue
+
     for (let i = 0; i < types.length; i++) {
       const type = types[i]
 
       for (let j = 0; j < this.serializers.length; j++) {
         const serializer = this.serializers[j]
         if (serializer.isAble(type)) {
+          this.cache[types] = { serializer, type }
           return { serializer, type }
         }
       }
@@ -45,7 +51,8 @@ SerializerManager.expand = function (options, fallbackSerializer) {
 
   const serializers = options.serializers.map(c => new Serializer(c))
   return new SerializerManager({
-    serializers: serializers.concat(fallbackSerializer.serializers)
+    serializers: serializers.concat(fallbackSerializer.serializers),
+    cache: options.cache
   })
 }
 
diff --git a/index.js b/index.js
index 6ec398e..5e7ef29 100644
--- a/index.js
+++ b/index.js
@@ -6,6 +6,9 @@ const SerializerManager = require('./SerializerManager')
 const FASTIFY_DEFAULT_SERIALIZE_MIME_TYPE = 'application/json'
 
 function acceptsSerializerPlugin (fastify, options, next) {
+  const serializerCache = {}
+  options.cache = serializerCache
+
   const globalSerializerManager = SerializerManager.build(options)
 
   const defaultSerializer = globalSerializerManager.findSerializer([options.default])
@@ -17,6 +20,7 @@ function acceptsSerializerPlugin (fastify, options, next) {
     let serializer
     let type
 
+    reply.serializer.cache = serializerCache
     reply.serializer.serializerManager = SerializerManager.expand(reply.serializer, globalSerializerManager)
 
     const serializerManager = reply.serializer.serializerManager

From 7c93c8ad1c9b5baa3f9e68911eb49c31e97054f5 Mon Sep 17 00:00:00 2001
From: Simone Busoli <simone.busoli@nearform.com>
Date: Fri, 4 Dec 2020 10:39:40 +0100
Subject: [PATCH 2/2] test: add cache test

---
 test/test.js | 51 +++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 51 insertions(+)

diff --git a/test/test.js b/test/test.js
index e3ec9c5..c2c5bb2 100644
--- a/test/test.js
+++ b/test/test.js
@@ -365,3 +365,54 @@ test('serializer without conf', t => {
     })
   })
 })
+
+test('serializer cache', t => {
+  t.plan(1)
+
+  const fastify = Fastify()
+
+  fastify.register(plugin, {
+    serializers: [
+      {
+        regex: /^application\/cache$/,
+        serializer: (body) => body
+      }
+    ]
+  })
+
+  t.test('it shoud populate cache', t => {
+    t.plan(8)
+
+    fastify.get('/request', function (req, reply) {
+      t.strictDeepEqual(Object.keys(reply.serializer.cache), ['application/cache'])
+
+      reply.send('cache')
+    })
+
+    fastify.inject({
+      method: 'GET',
+      url: '/request',
+      payload: {},
+      headers: {
+        accept: 'application/cache'
+      }
+    }, (err, res) => {
+      t.error(err)
+      t.strictDeepEqual(res.headers['content-type'], 'application/cache')
+      t.strictDeepEqual(res.payload, 'cache')
+    })
+
+    fastify.inject({
+      method: 'GET',
+      url: '/request',
+      payload: {},
+      headers: {
+        accept: 'application/cache'
+      }
+    }, (err, res) => {
+      t.error(err)
+      t.strictDeepEqual(res.headers['content-type'], 'application/cache')
+      t.strictDeepEqual(res.payload, 'cache')
+    })
+  })
+})