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// Copyright 2010 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package http
import (
"bufio"
"bytes"
"errors"
"fmt"
"io"
"net"
"net/url"
"strings"
"testing"
"testing/iotest"
"time"
)
type reqWriteTest struct {
Req Request
Body any // optional []byte or func() io.ReadCloser to populate Req.Body
// Any of these three may be empty to skip that test.
WantWrite string // Request.Write
WantProxy string // Request.WriteProxy
WantError error // wanted error from Request.Write
}
var reqWriteTests = []reqWriteTest{
// HTTP/1.1 => chunked coding; no body; no trailer
0: {
Req: Request{
Method: "GET",
URL: &url.URL{
Scheme: "http",
Host: "www.techcrunch.com",
Path: "/",
},
Proto: "HTTP/1.1",
ProtoMajor: 1,
ProtoMinor: 1,
Header: Header{
"Accept": {"text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8"},
"Accept-Charset": {"ISO-8859-1,utf-8;q=0.7,*;q=0.7"},
"Accept-Encoding": {"gzip,deflate"},
"Accept-Language": {"en-us,en;q=0.5"},
"Keep-Alive": {"300"},
"Proxy-Connection": {"keep-alive"},
"User-Agent": {"Fake"},
},
Body: nil,
Close: false,
Host: "www.techcrunch.com",
Form: map[string][]string{},
},
WantWrite: "GET / HTTP/1.1\r\n" +
"Host: www.techcrunch.com\r\n" +
"User-Agent: Fake\r\n" +
"Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8\r\n" +
"Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7\r\n" +
"Accept-Encoding: gzip,deflate\r\n" +
"Accept-Language: en-us,en;q=0.5\r\n" +
"Keep-Alive: 300\r\n" +
"Proxy-Connection: keep-alive\r\n\r\n",
WantProxy: "GET http://www.techcrunch.com/ HTTP/1.1\r\n" +
"Host: www.techcrunch.com\r\n" +
"User-Agent: Fake\r\n" +
"Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8\r\n" +
"Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7\r\n" +
"Accept-Encoding: gzip,deflate\r\n" +
"Accept-Language: en-us,en;q=0.5\r\n" +
"Keep-Alive: 300\r\n" +
"Proxy-Connection: keep-alive\r\n\r\n",
},
// HTTP/1.1 => chunked coding; body; empty trailer
1: {
Req: Request{
Method: "GET",
URL: &url.URL{
Scheme: "http",
Host: "www.google.com",
Path: "/search",
},
ProtoMajor: 1,
ProtoMinor: 1,
Header: Header{},
TransferEncoding: []string{"chunked"},
},
Body: []byte("abcdef"),
WantWrite: "GET /search HTTP/1.1\r\n" +
"Host: www.google.com\r\n" +
"User-Agent: Go-http-client/1.1\r\n" +
"Transfer-Encoding: chunked\r\n\r\n" +
chunk("abcdef") + chunk(""),
WantProxy: "GET http://www.google.com/search HTTP/1.1\r\n" +
"Host: www.google.com\r\n" +
"User-Agent: Go-http-client/1.1\r\n" +
"Transfer-Encoding: chunked\r\n\r\n" +
chunk("abcdef") + chunk(""),
},
// HTTP/1.1 POST => chunked coding; body; empty trailer
2: {
Req: Request{
Method: "POST",
URL: &url.URL{
Scheme: "http",
Host: "www.google.com",
Path: "/search",
},
ProtoMajor: 1,
ProtoMinor: 1,
Header: Header{},
Close: true,
TransferEncoding: []string{"chunked"},
},
Body: []byte("abcdef"),
WantWrite: "POST /search HTTP/1.1\r\n" +
"Host: www.google.com\r\n" +
"User-Agent: Go-http-client/1.1\r\n" +
"Connection: close\r\n" +
"Transfer-Encoding: chunked\r\n\r\n" +
chunk("abcdef") + chunk(""),
WantProxy: "POST http://www.google.com/search HTTP/1.1\r\n" +
"Host: www.google.com\r\n" +
"User-Agent: Go-http-client/1.1\r\n" +
"Connection: close\r\n" +
"Transfer-Encoding: chunked\r\n\r\n" +
chunk("abcdef") + chunk(""),
},
// HTTP/1.1 POST with Content-Length, no chunking
3: {
Req: Request{
Method: "POST",
URL: &url.URL{
Scheme: "http",
Host: "www.google.com",
Path: "/search",
},
ProtoMajor: 1,
ProtoMinor: 1,
Header: Header{},
Close: true,
ContentLength: 6,
},
Body: []byte("abcdef"),
WantWrite: "POST /search HTTP/1.1\r\n" +
"Host: www.google.com\r\n" +
"User-Agent: Go-http-client/1.1\r\n" +
"Connection: close\r\n" +
"Content-Length: 6\r\n" +
"\r\n" +
"abcdef",
WantProxy: "POST http://www.google.com/search HTTP/1.1\r\n" +
"Host: www.google.com\r\n" +
"User-Agent: Go-http-client/1.1\r\n" +
"Connection: close\r\n" +
"Content-Length: 6\r\n" +
"\r\n" +
"abcdef",
},
// HTTP/1.1 POST with Content-Length in headers
4: {
Req: Request{
Method: "POST",
URL: mustParseURL("http://example.com/"),
Host: "example.com",
Header: Header{
"Content-Length": []string{"10"}, // ignored
},
ContentLength: 6,
},
Body: []byte("abcdef"),
WantWrite: "POST / HTTP/1.1\r\n" +
"Host: example.com\r\n" +
"User-Agent: Go-http-client/1.1\r\n" +
"Content-Length: 6\r\n" +
"\r\n" +
"abcdef",
WantProxy: "POST http://example.com/ HTTP/1.1\r\n" +
"Host: example.com\r\n" +
"User-Agent: Go-http-client/1.1\r\n" +
"Content-Length: 6\r\n" +
"\r\n" +
"abcdef",
},
// default to HTTP/1.1
5: {
Req: Request{
Method: "GET",
URL: mustParseURL("/search"),
Host: "www.google.com",
},
WantWrite: "GET /search HTTP/1.1\r\n" +
"Host: www.google.com\r\n" +
"User-Agent: Go-http-client/1.1\r\n" +
"\r\n",
},
// Request with a 0 ContentLength and a 0 byte body.
6: {
Req: Request{
Method: "POST",
URL: mustParseURL("/"),
Host: "example.com",
ProtoMajor: 1,
ProtoMinor: 1,
ContentLength: 0, // as if unset by user
},
Body: func() io.ReadCloser { return io.NopCloser(io.LimitReader(strings.NewReader("xx"), 0)) },
WantWrite: "POST / HTTP/1.1\r\n" +
"Host: example.com\r\n" +
"User-Agent: Go-http-client/1.1\r\n" +
"Transfer-Encoding: chunked\r\n" +
"\r\n0\r\n\r\n",
WantProxy: "POST / HTTP/1.1\r\n" +
"Host: example.com\r\n" +
"User-Agent: Go-http-client/1.1\r\n" +
"Transfer-Encoding: chunked\r\n" +
"\r\n0\r\n\r\n",
},
// Request with a 0 ContentLength and a nil body.
7: {
Req: Request{
Method: "POST",
URL: mustParseURL("/"),
Host: "example.com",
ProtoMajor: 1,
ProtoMinor: 1,
ContentLength: 0, // as if unset by user
},
Body: func() io.ReadCloser { return nil },
WantWrite: "POST / HTTP/1.1\r\n" +
"Host: example.com\r\n" +
"User-Agent: Go-http-client/1.1\r\n" +
"Content-Length: 0\r\n" +
"\r\n",
WantProxy: "POST / HTTP/1.1\r\n" +
"Host: example.com\r\n" +
"User-Agent: Go-http-client/1.1\r\n" +
"Content-Length: 0\r\n" +
"\r\n",
},
// Request with a 0 ContentLength and a 1 byte body.
8: {
Req: Request{
Method: "POST",
URL: mustParseURL("/"),
Host: "example.com",
ProtoMajor: 1,
ProtoMinor: 1,
ContentLength: 0, // as if unset by user
},
Body: func() io.ReadCloser { return io.NopCloser(io.LimitReader(strings.NewReader("xx"), 1)) },
WantWrite: "POST / HTTP/1.1\r\n" +
"Host: example.com\r\n" +
"User-Agent: Go-http-client/1.1\r\n" +
"Transfer-Encoding: chunked\r\n\r\n" +
chunk("x") + chunk(""),
WantProxy: "POST / HTTP/1.1\r\n" +
"Host: example.com\r\n" +
"User-Agent: Go-http-client/1.1\r\n" +
"Transfer-Encoding: chunked\r\n\r\n" +
chunk("x") + chunk(""),
},
// Request with a ContentLength of 10 but a 5 byte body.
9: {
Req: Request{
Method: "POST",
URL: mustParseURL("/"),
Host: "example.com",
ProtoMajor: 1,
ProtoMinor: 1,
ContentLength: 10, // but we're going to send only 5 bytes
},
Body: []byte("12345"),
WantError: errors.New("http: ContentLength=10 with Body length 5"),
},
// Request with a ContentLength of 4 but an 8 byte body.
10: {
Req: Request{
Method: "POST",
URL: mustParseURL("/"),
Host: "example.com",
ProtoMajor: 1,
ProtoMinor: 1,
ContentLength: 4, // but we're going to try to send 8 bytes
},
Body: []byte("12345678"),
WantError: errors.New("http: ContentLength=4 with Body length 8"),
},
// Request with a 5 ContentLength and nil body.
11: {
Req: Request{
Method: "POST",
URL: mustParseURL("/"),
Host: "example.com",
ProtoMajor: 1,
ProtoMinor: 1,
ContentLength: 5, // but we'll omit the body
},
WantError: errors.New("http: Request.ContentLength=5 with nil Body"),
},
// Request with a 0 ContentLength and a body with 1 byte content and an error.
12: {
Req: Request{
Method: "POST",
URL: mustParseURL("/"),
Host: "example.com",
ProtoMajor: 1,
ProtoMinor: 1,
ContentLength: 0, // as if unset by user
},
Body: func() io.ReadCloser {
err := errors.New("Custom reader error")
errReader := iotest.ErrReader(err)
return io.NopCloser(io.MultiReader(strings.NewReader("x"), errReader))
},
WantError: errors.New("Custom reader error"),
},
// Request with a 0 ContentLength and a body without content and an error.
13: {
Req: Request{
Method: "POST",
URL: mustParseURL("/"),
Host: "example.com",
ProtoMajor: 1,
ProtoMinor: 1,
ContentLength: 0, // as if unset by user
},
Body: func() io.ReadCloser {
err := errors.New("Custom reader error")
errReader := iotest.ErrReader(err)
return io.NopCloser(errReader)
},
WantError: errors.New("Custom reader error"),
},
// Verify that DumpRequest preserves the HTTP version number, doesn't add a Host,
// and doesn't add a User-Agent.
14: {
Req: Request{
Method: "GET",
URL: mustParseURL("/foo"),
ProtoMajor: 1,
ProtoMinor: 0,
Header: Header{
"X-Foo": []string{"X-Bar"},
},
},
WantWrite: "GET /foo HTTP/1.1\r\n" +
"Host: \r\n" +
"User-Agent: Go-http-client/1.1\r\n" +
"X-Foo: X-Bar\r\n\r\n",
},
// If no Request.Host and no Request.URL.Host, we send
// an empty Host header, and don't use
// Request.Header["Host"]. This is just testing that
// we don't change Go 1.0 behavior.
15: {
Req: Request{
Method: "GET",
Host: "",
URL: &url.URL{
Scheme: "http",
Host: "",
Path: "/search",
},
ProtoMajor: 1,
ProtoMinor: 1,
Header: Header{
"Host": []string{"bad.example.com"},
},
},
WantWrite: "GET /search HTTP/1.1\r\n" +
"Host: \r\n" +
"User-Agent: Go-http-client/1.1\r\n\r\n",
},
// Opaque test #1 from golang.org/issue/4860
16: {
Req: Request{
Method: "GET",
URL: &url.URL{
Scheme: "http",
Host: "www.google.com",
Opaque: "/%2F/%2F/",
},
ProtoMajor: 1,
ProtoMinor: 1,
Header: Header{},
},
WantWrite: "GET /%2F/%2F/ HTTP/1.1\r\n" +
"Host: www.google.com\r\n" +
"User-Agent: Go-http-client/1.1\r\n\r\n",
},
// Opaque test #2 from golang.org/issue/4860
17: {
Req: Request{
Method: "GET",
URL: &url.URL{
Scheme: "http",
Host: "x.google.com",
Opaque: "//y.google.com/%2F/%2F/",
},
ProtoMajor: 1,
ProtoMinor: 1,
Header: Header{},
},
WantWrite: "GET http://y.google.com/%2F/%2F/ HTTP/1.1\r\n" +
"Host: x.google.com\r\n" +
"User-Agent: Go-http-client/1.1\r\n\r\n",
},
// Testing custom case in header keys. Issue 5022.
18: {
Req: Request{
Method: "GET",
URL: &url.URL{
Scheme: "http",
Host: "www.google.com",
Path: "/",
},
Proto: "HTTP/1.1",
ProtoMajor: 1,
ProtoMinor: 1,
Header: Header{
"ALL-CAPS": {"x"},
},
},
WantWrite: "GET / HTTP/1.1\r\n" +
"Host: www.google.com\r\n" +
"User-Agent: Go-http-client/1.1\r\n" +
"ALL-CAPS: x\r\n" +
"\r\n",
},
// Request with host header field; IPv6 address with zone identifier
19: {
Req: Request{
Method: "GET",
URL: &url.URL{
Host: "[fe80::1%en0]",
},
},
WantWrite: "GET / HTTP/1.1\r\n" +
"Host: [fe80::1]\r\n" +
"User-Agent: Go-http-client/1.1\r\n" +
"\r\n",
},
// Request with optional host header field; IPv6 address with zone identifier
20: {
Req: Request{
Method: "GET",
URL: &url.URL{
Host: "www.example.com",
},
Host: "[fe80::1%en0]:8080",
},
WantWrite: "GET / HTTP/1.1\r\n" +
"Host: [fe80::1]:8080\r\n" +
"User-Agent: Go-http-client/1.1\r\n" +
"\r\n",
},
// CONNECT without Opaque
21: {
Req: Request{
Method: "CONNECT",
URL: &url.URL{
Scheme: "https", // of proxy.com
Host: "proxy.com",
},
},
// What we used to do, locking that behavior in:
WantWrite: "CONNECT proxy.com HTTP/1.1\r\n" +
"Host: proxy.com\r\n" +
"User-Agent: Go-http-client/1.1\r\n" +
"\r\n",
},
// CONNECT with Opaque
22: {
Req: Request{
Method: "CONNECT",
URL: &url.URL{
Scheme: "https", // of proxy.com
Host: "proxy.com",
Opaque: "backend:443",
},
},
WantWrite: "CONNECT backend:443 HTTP/1.1\r\n" +
"Host: proxy.com\r\n" +
"User-Agent: Go-http-client/1.1\r\n" +
"\r\n",
},
// Verify that a nil header value doesn't get written.
23: {
Req: Request{
Method: "GET",
URL: mustParseURL("/foo"),
Header: Header{
"X-Foo": []string{"X-Bar"},
"X-Idempotency-Key": nil,
},
},
WantWrite: "GET /foo HTTP/1.1\r\n" +
"Host: \r\n" +
"User-Agent: Go-http-client/1.1\r\n" +
"X-Foo: X-Bar\r\n\r\n",
},
24: {
Req: Request{
Method: "GET",
URL: mustParseURL("/foo"),
Header: Header{
"X-Foo": []string{"X-Bar"},
"X-Idempotency-Key": []string{},
},
},
WantWrite: "GET /foo HTTP/1.1\r\n" +
"Host: \r\n" +
"User-Agent: Go-http-client/1.1\r\n" +
"X-Foo: X-Bar\r\n\r\n",
},
25: {
Req: Request{
Method: "GET",
URL: &url.URL{
Host: "www.example.com",
RawQuery: "new\nline", // or any CTL
},
},
WantError: errors.New("net/http: can't write control character in Request.URL"),
},
26: { // Request with nil body and PATCH method. Issue #40978
Req: Request{
Method: "PATCH",
URL: mustParseURL("/"),
Host: "example.com",
ProtoMajor: 1,
ProtoMinor: 1,
ContentLength: 0, // as if unset by user
},
Body: nil,
WantWrite: "PATCH / HTTP/1.1\r\n" +
"Host: example.com\r\n" +
"User-Agent: Go-http-client/1.1\r\n" +
"Content-Length: 0\r\n\r\n",
WantProxy: "PATCH / HTTP/1.1\r\n" +
"Host: example.com\r\n" +
"User-Agent: Go-http-client/1.1\r\n" +
"Content-Length: 0\r\n\r\n",
},
}
func TestRequestWrite(t *testing.T) {
for i := range reqWriteTests {
tt := &reqWriteTests[i]
setBody := func() {
if tt.Body == nil {
return
}
switch b := tt.Body.(type) {
case []byte:
tt.Req.Body = io.NopCloser(bytes.NewReader(b))
case func() io.ReadCloser:
tt.Req.Body = b()
}
}
setBody()
if tt.Req.Header == nil {
tt.Req.Header = make(Header)
}
var braw strings.Builder
err := tt.Req.Write(&braw)
if g, e := fmt.Sprintf("%v", err), fmt.Sprintf("%v", tt.WantError); g != e {
t.Errorf("writing #%d, err = %q, want %q", i, g, e)
continue
}
if err != nil {
continue
}
if tt.WantWrite != "" {
sraw := braw.String()
if sraw != tt.WantWrite {
t.Errorf("Test %d, expecting:\n%s\nGot:\n%s\n", i, tt.WantWrite, sraw)
continue
}
}
if tt.WantProxy != "" {
setBody()
var praw strings.Builder
err = tt.Req.WriteProxy(&praw)
if err != nil {
t.Errorf("WriteProxy #%d: %s", i, err)
continue
}
sraw := praw.String()
if sraw != tt.WantProxy {
t.Errorf("Test Proxy %d, expecting:\n%s\nGot:\n%s\n", i, tt.WantProxy, sraw)
continue
}
}
}
}
func TestRequestWriteTransport(t *testing.T) {
t.Parallel()
matchSubstr := func(substr string) func(string) error {
return func(written string) error {
if !strings.Contains(written, substr) {
return fmt.Errorf("expected substring %q in request: %s", substr, written)
}
return nil
}
}
noContentLengthOrTransferEncoding := func(req string) error {
if strings.Contains(req, "Content-Length: ") {
return fmt.Errorf("unexpected Content-Length in request: %s", req)
}
if strings.Contains(req, "Transfer-Encoding: ") {
return fmt.Errorf("unexpected Transfer-Encoding in request: %s", req)
}
return nil
}
all := func(checks ...func(string) error) func(string) error {
return func(req string) error {
for _, c := range checks {
if err := c(req); err != nil {
return err
}
}
return nil
}
}
type testCase struct {
method string
clen int64 // ContentLength
body io.ReadCloser
want func(string) error
// optional:
init func(*testCase)
afterReqRead func()
}
tests := []testCase{
{
method: "GET",
want: noContentLengthOrTransferEncoding,
},
{
method: "GET",
body: io.NopCloser(strings.NewReader("")),
want: noContentLengthOrTransferEncoding,
},
{
method: "GET",
clen: -1,
body: io.NopCloser(strings.NewReader("")),
want: noContentLengthOrTransferEncoding,
},
// A GET with a body, with explicit content length:
{
method: "GET",
clen: 7,
body: io.NopCloser(strings.NewReader("foobody")),
want: all(matchSubstr("Content-Length: 7"),
matchSubstr("foobody")),
},
// A GET with a body, sniffing the leading "f" from "foobody".
{
method: "GET",
clen: -1,
body: io.NopCloser(strings.NewReader("foobody")),
want: all(matchSubstr("Transfer-Encoding: chunked"),
matchSubstr("\r\n1\r\nf\r\n"),
matchSubstr("oobody")),
},
// But a POST request is expected to have a body, so
// no sniffing happens:
{
method: "POST",
clen: -1,
body: io.NopCloser(strings.NewReader("foobody")),
want: all(matchSubstr("Transfer-Encoding: chunked"),
matchSubstr("foobody")),
},
{
method: "POST",
clen: -1,
body: io.NopCloser(strings.NewReader("")),
want: all(matchSubstr("Transfer-Encoding: chunked")),
},
// Verify that a blocking Request.Body doesn't block forever.
{
method: "GET",
clen: -1,
init: func(tt *testCase) {
pr, pw := io.Pipe()
tt.afterReqRead = func() {
pw.Close()
}
tt.body = io.NopCloser(pr)
},
want: matchSubstr("Transfer-Encoding: chunked"),
},
}
for i, tt := range tests {
if tt.init != nil {
tt.init(&tt)
}
req := &Request{
Method: tt.method,
URL: &url.URL{
Scheme: "http",
Host: "example.com",
},
Header: make(Header),
ContentLength: tt.clen,
Body: tt.body,
}
got, err := dumpRequestOut(req, tt.afterReqRead)
if err != nil {
t.Errorf("test[%d]: %v", i, err)
continue
}
if err := tt.want(string(got)); err != nil {
t.Errorf("test[%d]: %v", i, err)
}
}
}
type closeChecker struct {
io.Reader
closed bool
}
func (rc *closeChecker) Close() error {
rc.closed = true
return nil
}
// TestRequestWriteClosesBody tests that Request.Write closes its request.Body.
// It also indirectly tests NewRequest and that it doesn't wrap an existing Closer
// inside a NopCloser, and that it serializes it correctly.
func TestRequestWriteClosesBody(t *testing.T) {
rc := &closeChecker{Reader: strings.NewReader("my body")}
req, err := NewRequest("POST", "http://foo.com/", rc)
if err != nil {
t.Fatal(err)
}
buf := new(strings.Builder)
if err := req.Write(buf); err != nil {
t.Error(err)
}
if !rc.closed {
t.Error("body not closed after write")
}
expected := "POST / HTTP/1.1\r\n" +
"Host: foo.com\r\n" +
"User-Agent: Go-http-client/1.1\r\n" +
"Transfer-Encoding: chunked\r\n\r\n" +
chunk("my body") +
chunk("")
if buf.String() != expected {
t.Errorf("write:\n got: %s\nwant: %s", buf.String(), expected)
}
}
func chunk(s string) string {
return fmt.Sprintf("%x\r\n%s\r\n", len(s), s)
}
func mustParseURL(s string) *url.URL {
u, err := url.Parse(s)
if err != nil {
panic(fmt.Sprintf("Error parsing URL %q: %v", s, err))
}
return u
}
type writerFunc func([]byte) (int, error)
func (f writerFunc) Write(p []byte) (int, error) { return f(p) }
// TestRequestWriteError tests the Write err != nil checks in (*Request).write.
func TestRequestWriteError(t *testing.T) {
failAfter, writeCount := 0, 0
errFail := errors.New("fake write failure")
// w is the buffered io.Writer to write the request to. It
// fails exactly once on its Nth Write call, as controlled by
// failAfter. It also tracks the number of calls in
// writeCount.
w := struct {
io.ByteWriter // to avoid being wrapped by a bufio.Writer
io.Writer
}{
nil,
writerFunc(func(p []byte) (n int, err error) {
writeCount++
if failAfter == 0 {
err = errFail
}
failAfter--
return len(p), err
}),
}
req, _ := NewRequest("GET", "http://example.com/", nil)
const writeCalls = 4 // number of Write calls in current implementation
sawGood := false
for n := 0; n <= writeCalls+2; n++ {
failAfter = n
writeCount = 0
err := req.Write(w)
var wantErr error
if n < writeCalls {
wantErr = errFail
}
if err != wantErr {
t.Errorf("for fail-after %d Writes, err = %v; want %v", n, err, wantErr)
continue
}
if err == nil {
sawGood = true
if writeCount != writeCalls {
t.Fatalf("writeCalls constant is outdated in test")
}
}
if writeCount > writeCalls || writeCount > n+1 {
t.Errorf("for fail-after %d, saw unexpectedly high (%d) write calls", n, writeCount)
}
}
if !sawGood {
t.Fatalf("writeCalls constant is outdated in test")
}
}
// dumpRequestOut is a modified copy of net/http/httputil.DumpRequestOut.
// Unlike the original, this version doesn't mutate the req.Body and
// try to restore it. It always dumps the whole body.
// And it doesn't support https.
func dumpRequestOut(req *Request, onReadHeaders func()) ([]byte, error) {
// Use the actual Transport code to record what we would send
// on the wire, but not using TCP. Use a Transport with a
// custom dialer that returns a fake net.Conn that waits
// for the full input (and recording it), and then responds
// with a dummy response.
var buf bytes.Buffer // records the output
pr, pw := io.Pipe()
defer pr.Close()
defer pw.Close()
dr := &delegateReader{c: make(chan io.Reader)}
t := &Transport{
Dial: func(net, addr string) (net.Conn, error) {
return &dumpConn{io.MultiWriter(&buf, pw), dr}, nil
},
}
defer t.CloseIdleConnections()
// Wait for the request before replying with a dummy response:
go func() {
req, err := ReadRequest(bufio.NewReader(pr))
if err == nil {
if onReadHeaders != nil {
onReadHeaders()
}
// Ensure all the body is read; otherwise
// we'll get a partial dump.
io.Copy(io.Discard, req.Body)
req.Body.Close()
}
dr.c <- strings.NewReader("HTTP/1.1 204 No Content\r\nConnection: close\r\n\r\n")
}()
_, err := t.RoundTrip(req)
if err != nil {
return nil, err
}
return buf.Bytes(), nil
}
// delegateReader is a reader that delegates to another reader,
// once it arrives on a channel.
type delegateReader struct {
c chan io.Reader
r io.Reader // nil until received from c
}
func (r *delegateReader) Read(p []byte) (int, error) {
if r.r == nil {
r.r = <-r.c
}
return r.r.Read(p)
}
// dumpConn is a net.Conn that writes to Writer and reads from Reader.
type dumpConn struct {
io.Writer
io.Reader
}
func (c *dumpConn) Close() error { return nil }
func (c *dumpConn) LocalAddr() net.Addr { return nil }
func (c *dumpConn) RemoteAddr() net.Addr { return nil }
func (c *dumpConn) SetDeadline(t time.Time) error { return nil }
func (c *dumpConn) SetReadDeadline(t time.Time) error { return nil }
func (c *dumpConn) SetWriteDeadline(t time.Time) error { return nil }