new/http: add request file upload benchmarks

This adds a couple of benchmarks to test file uploads using PUT
requests.

It's designed to complement changes https://golang.org/cl/163599 and
https://golang.org/cl/163737, allowing an easy comparison of
performance before and after these changes are applied.

Updates #30377.

Author: vancluever

src/net/http/request_test.go

@@ -8,12 +8,15 @@ import (
 	"bufio"
 	"bytes"
 	"context"
+	"crypto/rand"
+	"crypto/tls"
 	"encoding/base64"
 	"fmt"
 	"io"
 	"io/ioutil"
 	"mime/multipart"
 	. "net/http"
+	"net/http/httptest"
 	"net/url"
 	"os"
 	"reflect"
@@ -1046,3 +1049,94 @@ func BenchmarkReadRequestWrk(b *testing.B) {
 Host: localhost:8080
 `)
 }
+
+const benchmarkRequestWriteFileSize = 10240000
+
+func benchmarkRequestFileAndServer(useTLS bool) (*os.File, func(), *httptest.Server, func(), error) {
+	tf, err := ioutil.TempFile("", "go-bench-http")
+	if err != nil {
+		return nil, nil, nil, nil, err
+	}
+
+	if _, err = io.Copy(tf, io.LimitReader(rand.Reader, benchmarkRequestWriteFileSize)); err != nil {
+		return nil, nil, nil, nil, err
+	}
+
+	tf.Close()
+	tf, err = os.Open(tf.Name())
+	if err != nil {
+		return nil, nil, nil, nil, err
+	}
+
+	var ts *httptest.Server
+	hf := HandlerFunc(func(w ResponseWriter, r *Request) {
+		n, err := io.Copy(ioutil.Discard, r.Body)
+		if err != nil {
+			panic(err)
+		}
+
+		if n != benchmarkRequestWriteFileSize {
+			panic(fmt.Errorf("expected %d bytes read, got %d", benchmarkRequestWriteFileSize, n))
+		}
+
+		r.Body.Close()
+		w.WriteHeader(200)
+	})
+
+	if useTLS {
+		ts = httptest.NewTLSServer(hf)
+	} else {
+		ts = httptest.NewServer(hf)
+	}
+
+	return tf, func() { tf.Close(); os.Remove(tf.Name()) }, ts, func() { ts.Close() }, nil
+}
+
+func runBenchmarkRequestWriteFile(b *testing.B, useTLS bool) {
+	tf, tfClose, ts, tsClose, err := benchmarkRequestFileAndServer(useTLS)
+	if err != nil {
+		b.Fatal(err)
+	}
+
+	defer tsClose()
+	defer tfClose()
+
+	tr := new(Transport)
+	if useTLS {
+		tr.TLSClientConfig = &tls.Config{
+			InsecureSkipVerify: true,
+		}
+	}
+
+	c := &Client{Transport: tr}
+	r := ioutil.NopCloser(tf)
+
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		req, err := NewRequest("PUT", ts.URL, r)
+		if err != nil {
+			b.Fatal(err)
+		}
+
+		req.ContentLength = benchmarkRequestWriteFileSize
+		req.Header.Add("Content-Type", "application/octet-stream")
+		_, err = c.Do(req)
+		if err != nil {
+			b.Fatal(err)
+		}
+
+		b.SetBytes(benchmarkRequestWriteFileSize)
+
+		if _, err := tf.Seek(0, 0); err != nil {
+			b.Fatal(err)
+		}
+	}
+}
+
+func BenchmarkRequestWriteFileNoTLS(b *testing.B) {
+	runBenchmarkRequestWriteFile(b, false)
+}
+
+func BenchmarkRequestWriteFileWithTLS(b *testing.B) {
+	runBenchmarkRequestWriteFile(b, true)
+}