fix: spwan pool on request when use agent

lib/request.js

@@ -112,6 +112,7 @@ function buildRequest (opts) {
 
   function handleUndici (opts, done) {
     const req = {
+      origin: baseUrl || opts.url.origin,
       path: opts.url.pathname + opts.qs,
       method: opts.method,
       headers: Object.assign({}, opts.headers),
@@ -128,9 +129,7 @@ function buildRequest (opts) {
       done(new Error('unix socket not supported with undici yet'))
       return
     } else {
-      const options = getUndiciOptions(undiciOpts)
-      options.dispatcher = undiciAgent
-      pool = new undici.Pool(baseUrl || opts.url.origin, options)
+      pool = undiciAgent
     }
 
     // remove forbidden headers

test/undici-agent.js

@@ -0,0 +1,77 @@
+'use strict'
+
+const t = require('tap')
+const Fastify = require('fastify')
+const proxyquire = require('proxyquire')
+const http = require('http')
+const get = require('simple-get').concat
+const undici = require('undici')
+const { getUndiciOptions } = require('../lib/request')
+
+t.plan(10)
+
+const instance = Fastify()
+t.teardown(instance.close.bind(instance))
+
+const target = http.createServer((req, res) => {
+  res.statusCode = 200
+  res.end('hello world')
+})
+
+instance.get('/', (request, reply) => {
+  reply.from()
+})
+
+t.teardown(target.close.bind(target))
+
+target.listen(0, err => {
+  t.error(err)
+  let poolCreation = 0
+
+  const From = proxyquire('..', {
+    './lib/request.js': proxyquire('../lib/request.js', {
+      undici: proxyquire('undici', {
+        './lib/agent': proxyquire('undici/lib/agent.js', {
+          './pool': class Pool extends undici.Pool {
+            constructor (url, options) {
+              super(url, options)
+              poolCreation++
+            }
+          }
+        })
+      })
+    })
+  })
+
+  instance.register(From, {
+    base: `http://localhost:${target.address().port}`,
+    undici: buildUndiciOptions()
+  })
+
+  instance.listen(0, err => {
+    t.error(err)
+
+    get(`http://localhost:${instance.server.address().port}`, (err, res, data) => {
+      t.error(err)
+      t.equal(res.statusCode, 200)
+      t.equal(data.toString(), 'hello world')
+      t.equal(poolCreation, 1)
+
+      get(`http://localhost:${instance.server.address().port}`, (err, res, data) => {
+        t.error(err)
+        t.equal(res.statusCode, 200)
+        t.equal(data.toString(), 'hello world')
+        t.equal(poolCreation, 1)
+      })
+    })
+  })
+})
+
+function buildUndiciOptions () {
+  return getUndiciOptions({
+    connections: 42,
+    pipelining: 24,
+    keepAliveTimeout: 4242,
+    strictContentLength: false
+  })
+}

test/undici-options.js

@@ -10,7 +10,7 @@ const { getUndiciOptions } = require('../lib/request')
 
 const instance = Fastify()
 
-t.plan(7)
+t.plan(6)
 t.teardown(instance.close.bind(instance))
 
 const target = http.createServer((req, res) => {