src/net/http/client_test.go

   1 // Copyright 2009 The Go Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style
   3 // license that can be found in the LICENSE file.
   4
   5 // Tests for client.go
   6
   7 package http_test
   8
   9 import (
  10         "bytes"
  11         "context"
  12         "crypto/tls"
  13         "encoding/base64"
  14         "errors"
  15         "fmt"
  16         "internal/testenv"
  17         "io"
  18         "log"
  19         "net"
  20         . "net/http"
  21         "net/http/cookiejar"
  22         "net/http/httptest"
  23         "net/url"
  24         "reflect"
  25         "runtime"
  26         "strconv"
  27         "strings"
  28         "sync"
  29         "sync/atomic"
  30         "testing"
  31         "time"
  32 )
  33
  34 var robotsTxtHandler = HandlerFunc(func(w ResponseWriter, r *Request) {
  35         w.Header().Set("Last-Modified", "sometime")
  36         fmt.Fprintf(w, "User-agent: go\nDisallow: /something/")
  37 })
  38
  39 // pedanticReadAll works like io.ReadAll but additionally
  40 // verifies that r obeys the documented io.Reader contract.
  41 func pedanticReadAll(r io.Reader) (b []byte, err error) {
  42         var bufa [64]byte
  43         buf := bufa[:]
  44         for {
  45                 n, err := r.Read(buf)
  46                 if n == 0 && err == nil {
  47                         return nil, fmt.Errorf("Read: n=0 with err=nil")
  48                 }
  49                 b = append(b, buf[:n]...)
  50                 if err == io.EOF {
  51                         n, err := r.Read(buf)
  52                         if n != 0 || err != io.EOF {
  53                                 return nil, fmt.Errorf("Read: n=%d err=%#v after EOF", n, err)
  54                         }
  55                         return b, nil
  56                 }
  57                 if err != nil {
  58                         return b, err
  59                 }
  60         }
  61 }
  62
  63 type chanWriter chan string
  64
  65 func (w chanWriter) Write(p []byte) (n int, err error) {
  66         w <- string(p)
  67         return len(p), nil
  68 }
  69
  70 func TestClient(t *testing.T) {
  71         setParallel(t)
  72         defer afterTest(t)
  73         ts := httptest.NewServer(robotsTxtHandler)
  74         defer ts.Close()
  75
  76         c := ts.Client()
  77         r, err := c.Get(ts.URL)
  78         var b []byte
  79         if err == nil {
  80                 b, err = pedanticReadAll(r.Body)
  81                 r.Body.Close()
  82         }
  83         if err != nil {
  84                 t.Error(err)
  85         } else if s := string(b); !strings.HasPrefix(s, "User-agent:") {
  86                 t.Errorf("Incorrect page body (did not begin with User-agent): %q", s)
  87         }
  88 }
  89
  90 func TestClientHead_h1(t *testing.T) { testClientHead(t, h1Mode) }
  91 func TestClientHead_h2(t *testing.T) { testClientHead(t, h2Mode) }
  92
  93 func testClientHead(t *testing.T, h2 bool) {
  94         defer afterTest(t)
  95         cst := newClientServerTest(t, h2, robotsTxtHandler)
  96         defer cst.close()
  97
  98         r, err := cst.c.Head(cst.ts.URL)
  99         if err != nil {
 100                 t.Fatal(err)
 101         }
 102         if _, ok := r.Header["Last-Modified"]; !ok {
 103                 t.Error("Last-Modified header not found.")
 104         }
 105 }
 106
 107 type recordingTransport struct {
 108         req *Request
 109 }
 110
 111 func (t *recordingTransport) RoundTrip(req *Request) (resp *Response, err error) {
 112         t.req = req
 113         return nil, errors.New("dummy impl")
 114 }
 115
 116 func TestGetRequestFormat(t *testing.T) {
 117         setParallel(t)
 118         defer afterTest(t)
 119         tr := &recordingTransport{}
 120         client := &Client{Transport: tr}
 121         url := "http://dummy.faketld/"
 122         client.Get(url) // Note: doesn't hit network
 123         if tr.req.Method != "GET" {
 124                 t.Errorf("expected method %q; got %q", "GET", tr.req.Method)
 125         }
 126         if tr.req.URL.String() != url {
 127                 t.Errorf("expected URL %q; got %q", url, tr.req.URL.String())
 128         }
 129         if tr.req.Header == nil {
 130                 t.Errorf("expected non-nil request Header")
 131         }
 132 }
 133
 134 func TestPostRequestFormat(t *testing.T) {
 135         defer afterTest(t)
 136         tr := &recordingTransport{}
 137         client := &Client{Transport: tr}
 138
 139         url := "http://dummy.faketld/"
 140         json := `{"key":"value"}`
 141         b := strings.NewReader(json)
 142         client.Post(url, "application/json", b) // Note: doesn't hit network
 143
 144         if tr.req.Method != "POST" {
 145                 t.Errorf("got method %q, want %q", tr.req.Method, "POST")
 146         }
 147         if tr.req.URL.String() != url {
 148                 t.Errorf("got URL %q, want %q", tr.req.URL.String(), url)
 149         }
 150         if tr.req.Header == nil {
 151                 t.Fatalf("expected non-nil request Header")
 152         }
 153         if tr.req.Close {
 154                 t.Error("got Close true, want false")
 155         }
 156         if g, e := tr.req.ContentLength, int64(len(json)); g != e {
 157                 t.Errorf("got ContentLength %d, want %d", g, e)
 158         }
 159 }
 160
 161 func TestPostFormRequestFormat(t *testing.T) {
 162         defer afterTest(t)
 163         tr := &recordingTransport{}
 164         client := &Client{Transport: tr}
 165
 166         urlStr := "http://dummy.faketld/"
 167         form := make(url.Values)
 168         form.Set("foo", "bar")
 169         form.Add("foo", "bar2")
 170         form.Set("bar", "baz")
 171         client.PostForm(urlStr, form) // Note: doesn't hit network
 172
 173         if tr.req.Method != "POST" {
 174                 t.Errorf("got method %q, want %q", tr.req.Method, "POST")
 175         }
 176         if tr.req.URL.String() != urlStr {
 177                 t.Errorf("got URL %q, want %q", tr.req.URL.String(), urlStr)
 178         }
 179         if tr.req.Header == nil {
 180                 t.Fatalf("expected non-nil request Header")
 181         }
 182         if g, e := tr.req.Header.Get("Content-Type"), "application/x-www-form-urlencoded"; g != e {
 183                 t.Errorf("got Content-Type %q, want %q", g, e)
 184         }
 185         if tr.req.Close {
 186                 t.Error("got Close true, want false")
 187         }
 188         // Depending on map iteration, body can be either of these.
 189         expectedBody := "foo=bar&foo=bar2&bar=baz"
 190         expectedBody1 := "bar=baz&foo=bar&foo=bar2"
 191         if g, e := tr.req.ContentLength, int64(len(expectedBody)); g != e {
 192                 t.Errorf("got ContentLength %d, want %d", g, e)
 193         }
 194         bodyb, err := io.ReadAll(tr.req.Body)
 195         if err != nil {
 196                 t.Fatalf("ReadAll on req.Body: %v", err)
 197         }
 198         if g := string(bodyb); g != expectedBody && g != expectedBody1 {
 199                 t.Errorf("got body %q, want %q or %q", g, expectedBody, expectedBody1)
 200         }
 201 }
 202
 203 func TestClientRedirects(t *testing.T) {
 204         setParallel(t)
 205         defer afterTest(t)
 206         var ts *httptest.Server
 207         ts = httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
 208                 n, _ := strconv.Atoi(r.FormValue("n"))
 209                 // Test Referer header. (7 is arbitrary position to test at)
 210                 if n == 7 {
 211                         if g, e := r.Referer(), ts.URL+"/?n=6"; e != g {
 212                                 t.Errorf("on request ?n=7, expected referer of %q; got %q", e, g)
 213                         }
 214                 }
 215                 if n < 15 {
 216                         Redirect(w, r, fmt.Sprintf("/?n=%d", n+1), StatusTemporaryRedirect)
 217                         return
 218                 }
 219                 fmt.Fprintf(w, "n=%d", n)
 220         }))
 221         defer ts.Close()
 222
 223         c := ts.Client()
 224         _, err := c.Get(ts.URL)
 225         if e, g := `Get "/?n=10": stopped after 10 redirects`, fmt.Sprintf("%v", err); e != g {
 226                 t.Errorf("with default client Get, expected error %q, got %q", e, g)
 227         }
 228
 229         // HEAD request should also have the ability to follow redirects.
 230         _, err = c.Head(ts.URL)
 231         if e, g := `Head "/?n=10": stopped after 10 redirects`, fmt.Sprintf("%v", err); e != g {
 232                 t.Errorf("with default client Head, expected error %q, got %q", e, g)
 233         }
 234
 235         // Do should also follow redirects.
 236         greq, _ := NewRequest("GET", ts.URL, nil)
 237         _, err = c.Do(greq)
 238         if e, g := `Get "/?n=10": stopped after 10 redirects`, fmt.Sprintf("%v", err); e != g {
 239                 t.Errorf("with default client Do, expected error %q, got %q", e, g)
 240         }
 241
 242         // Requests with an empty Method should also redirect (Issue 12705)
 243         greq.Method = ""
 244         _, err = c.Do(greq)
 245         if e, g := `Get "/?n=10": stopped after 10 redirects`, fmt.Sprintf("%v", err); e != g {
 246                 t.Errorf("with default client Do and empty Method, expected error %q, got %q", e, g)
 247         }
 248
 249         var checkErr error
 250         var lastVia []*Request
 251         var lastReq *Request
 252         c.CheckRedirect = func(req *Request, via []*Request) error {
 253                 lastReq = req
 254                 lastVia = via
 255                 return checkErr
 256         }
 257         res, err := c.Get(ts.URL)
 258         if err != nil {
 259                 t.Fatalf("Get error: %v", err)
 260         }
 261         res.Body.Close()
 262         finalURL := res.Request.URL.String()
 263         if e, g := "<nil>", fmt.Sprintf("%v", err); e != g {
 264                 t.Errorf("with custom client, expected error %q, got %q", e, g)
 265         }
 266         if !strings.HasSuffix(finalURL, "/?n=15") {
 267                 t.Errorf("expected final url to end in /?n=15; got url %q", finalURL)
 268         }
 269         if e, g := 15, len(lastVia); e != g {
 270                 t.Errorf("expected lastVia to have contained %d elements; got %d", e, g)
 271         }
 272
 273         // Test that Request.Cancel is propagated between requests (Issue 14053)
 274         creq, _ := NewRequest("HEAD", ts.URL, nil)
 275         cancel := make(chan struct{})
 276         creq.Cancel = cancel
 277         if _, err := c.Do(creq); err != nil {
 278                 t.Fatal(err)
 279         }
 280         if lastReq == nil {
 281                 t.Fatal("didn't see redirect")
 282         }
 283         if lastReq.Cancel != cancel {
 284                 t.Errorf("expected lastReq to have the cancel channel set on the initial req")
 285         }
 286
 287         checkErr = errors.New("no redirects allowed")
 288         res, err = c.Get(ts.URL)
 289         if urlError, ok := err.(*url.Error); !ok || urlError.Err != checkErr {
 290                 t.Errorf("with redirects forbidden, expected a *url.Error with our 'no redirects allowed' error inside; got %#v (%q)", err, err)
 291         }
 292         if res == nil {
 293                 t.Fatalf("Expected a non-nil Response on CheckRedirect failure (https://golang.org/issue/3795)")
 294         }
 295         res.Body.Close()
 296         if res.Header.Get("Location") == "" {
 297                 t.Errorf("no Location header in Response")
 298         }
 299 }
 300
 301 // Tests that Client redirects' contexts are derived from the original request's context.
 302 func TestClientRedirectContext(t *testing.T) {
 303         setParallel(t)
 304         defer afterTest(t)
 305         ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
 306                 Redirect(w, r, "/", StatusTemporaryRedirect)
 307         }))
 308         defer ts.Close()
 309
 310         ctx, cancel := context.WithCancel(context.Background())
 311         c := ts.Client()
 312         c.CheckRedirect = func(req *Request, via []*Request) error {
 313                 cancel()
 314                 select {
 315                 case <-req.Context().Done():
 316                         return nil
 317                 case <-time.After(5 * time.Second):
 318                         return errors.New("redirected request's context never expired after root request canceled")
 319                 }
 320         }
 321         req, _ := NewRequestWithContext(ctx, "GET", ts.URL, nil)
 322         _, err := c.Do(req)
 323         ue, ok := err.(*url.Error)
 324         if !ok {
 325                 t.Fatalf("got error %T; want *url.Error", err)
 326         }
 327         if ue.Err != context.Canceled {
 328                 t.Errorf("url.Error.Err = %v; want %v", ue.Err, context.Canceled)
 329         }
 330 }
 331
 332 type redirectTest struct {
 333         suffix       string
 334         want         int // response code
 335         redirectBody string
 336 }
 337
 338 func TestPostRedirects(t *testing.T) {
 339         postRedirectTests := []redirectTest{
 340                 {"/", 200, "first"},
 341                 {"/?code=301&next=302", 200, "c301"},
 342                 {"/?code=302&next=302", 200, "c302"},
 343                 {"/?code=303&next=301", 200, "c303wc301"}, // Issue 9348
 344                 {"/?code=304", 304, "c304"},
 345                 {"/?code=305", 305, "c305"},
 346                 {"/?code=307&next=303,308,302", 200, "c307"},
 347                 {"/?code=308&next=302,301", 200, "c308"},
 348                 {"/?code=404", 404, "c404"},
 349         }
 350
 351         wantSegments := []string{
 352                 `POST / "first"`,
 353                 `POST /?code=301&next=302 "c301"`,
 354                 `GET /?code=302 ""`,
 355                 `GET / ""`,
 356                 `POST /?code=302&next=302 "c302"`,
 357                 `GET /?code=302 ""`,
 358                 `GET / ""`,
 359                 `POST /?code=303&next=301 "c303wc301"`,
 360                 `GET /?code=301 ""`,
 361                 `GET / ""`,
 362                 `POST /?code=304 "c304"`,
 363                 `POST /?code=305 "c305"`,
 364                 `POST /?code=307&next=303,308,302 "c307"`,
 365                 `POST /?code=303&next=308,302 "c307"`,
 366                 `GET /?code=308&next=302 ""`,
 367                 `GET /?code=302 "c307"`,
 368                 `GET / ""`,
 369                 `POST /?code=308&next=302,301 "c308"`,
 370                 `POST /?code=302&next=301 "c308"`,
 371                 `GET /?code=301 ""`,
 372                 `GET / ""`,
 373                 `POST /?code=404 "c404"`,
 374         }
 375         want := strings.Join(wantSegments, "\n")
 376         testRedirectsByMethod(t, "POST", postRedirectTests, want)
 377 }
 378
 379 func TestDeleteRedirects(t *testing.T) {
 380         deleteRedirectTests := []redirectTest{
 381                 {"/", 200, "first"},
 382                 {"/?code=301&next=302,308", 200, "c301"},
 383                 {"/?code=302&next=302", 200, "c302"},
 384                 {"/?code=303", 200, "c303"},
 385                 {"/?code=307&next=301,308,303,302,304", 304, "c307"},
 386                 {"/?code=308&next=307", 200, "c308"},
 387                 {"/?code=404", 404, "c404"},
 388         }
 389
 390         wantSegments := []string{
 391                 `DELETE / "first"`,
 392                 `DELETE /?code=301&next=302,308 "c301"`,
 393                 `GET /?code=302&next=308 ""`,
 394                 `GET /?code=308 ""`,
 395                 `GET / "c301"`,
 396                 `DELETE /?code=302&next=302 "c302"`,
 397                 `GET /?code=302 ""`,
 398                 `GET / ""`,
 399                 `DELETE /?code=303 "c303"`,
 400                 `GET / ""`,
 401                 `DELETE /?code=307&next=301,308,303,302,304 "c307"`,
 402                 `DELETE /?code=301&next=308,303,302,304 "c307"`,
 403                 `GET /?code=308&next=303,302,304 ""`,
 404                 `GET /?code=303&next=302,304 "c307"`,
 405                 `GET /?code=302&next=304 ""`,
 406                 `GET /?code=304 ""`,
 407                 `DELETE /?code=308&next=307 "c308"`,
 408                 `DELETE /?code=307 "c308"`,
 409                 `DELETE / "c308"`,
 410                 `DELETE /?code=404 "c404"`,
 411         }
 412         want := strings.Join(wantSegments, "\n")
 413         testRedirectsByMethod(t, "DELETE", deleteRedirectTests, want)
 414 }
 415
 416 func testRedirectsByMethod(t *testing.T, method string, table []redirectTest, want string) {
 417         defer afterTest(t)
 418         var log struct {
 419                 sync.Mutex
 420                 bytes.Buffer
 421         }
 422         var ts *httptest.Server
 423         ts = httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
 424                 log.Lock()
 425                 slurp, _ := io.ReadAll(r.Body)
 426                 fmt.Fprintf(&log.Buffer, "%s %s %q", r.Method, r.RequestURI, slurp)
 427                 if cl := r.Header.Get("Content-Length"); r.Method == "GET" && len(slurp) == 0 && (r.ContentLength != 0 || cl != "") {
 428                         fmt.Fprintf(&log.Buffer, " (but with body=%T, content-length = %v, %q)", r.Body, r.ContentLength, cl)
 429                 }
 430                 log.WriteByte('\n')
 431                 log.Unlock()
 432                 urlQuery := r.URL.Query()
 433                 if v := urlQuery.Get("code"); v != "" {
 434                         location := ts.URL
 435                         if final := urlQuery.Get("next"); final != "" {
 436                                 first, rest, _ := strings.Cut(final, ",")
 437                                 location = fmt.Sprintf("%s?code=%s", location, first)
 438                                 if rest != "" {
 439                                         location = fmt.Sprintf("%s&next=%s", location, rest)
 440                                 }
 441                         }
 442                         code, _ := strconv.Atoi(v)
 443                         if code/100 == 3 {
 444                                 w.Header().Set("Location", location)
 445                         }
 446                         w.WriteHeader(code)
 447                 }
 448         }))
 449         defer ts.Close()
 450
 451         c := ts.Client()
 452         for _, tt := range table {
 453                 content := tt.redirectBody
 454                 req, _ := NewRequest(method, ts.URL+tt.suffix, strings.NewReader(content))
 455                 req.GetBody = func() (io.ReadCloser, error) { return io.NopCloser(strings.NewReader(content)), nil }
 456                 res, err := c.Do(req)
 457
 458                 if err != nil {
 459                         t.Fatal(err)
 460                 }
 461                 if res.StatusCode != tt.want {
 462                         t.Errorf("POST %s: status code = %d; want %d", tt.suffix, res.StatusCode, tt.want)
 463                 }
 464         }
 465         log.Lock()
 466         got := log.String()
 467         log.Unlock()
 468
 469         got = strings.TrimSpace(got)
 470         want = strings.TrimSpace(want)
 471
 472         if got != want {
 473                 got, want, lines := removeCommonLines(got, want)
 474                 t.Errorf("Log differs after %d common lines.\n\nGot:\n%s\n\nWant:\n%s\n", lines, got, want)
 475         }
 476 }
 477
 478 func removeCommonLines(a, b string) (asuffix, bsuffix string, commonLines int) {
 479         for {
 480                 nl := strings.IndexByte(a, '\n')
 481                 if nl < 0 {
 482                         return a, b, commonLines
 483                 }
 484                 line := a[:nl+1]
 485                 if !strings.HasPrefix(b, line) {
 486                         return a, b, commonLines
 487                 }
 488                 commonLines++
 489                 a = a[len(line):]
 490                 b = b[len(line):]
 491         }
 492 }
 493
 494 func TestClientRedirectUseResponse(t *testing.T) {
 495         setParallel(t)
 496         defer afterTest(t)
 497         const body = "Hello, world."
 498         var ts *httptest.Server
 499         ts = httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
 500                 if strings.Contains(r.URL.Path, "/other") {
 501                         io.WriteString(w, "wrong body")
 502                 } else {
 503                         w.Header().Set("Location", ts.URL+"/other")
 504                         w.WriteHeader(StatusFound)
 505                         io.WriteString(w, body)
 506                 }
 507         }))
 508         defer ts.Close()
 509
 510         c := ts.Client()
 511         c.CheckRedirect = func(req *Request, via []*Request) error {
 512                 if req.Response == nil {
 513                         t.Error("expected non-nil Request.Response")
 514                 }
 515                 return ErrUseLastResponse
 516         }
 517         res, err := c.Get(ts.URL)
 518         if err != nil {
 519                 t.Fatal(err)
 520         }
 521         if res.StatusCode != StatusFound {
 522                 t.Errorf("status = %d; want %d", res.StatusCode, StatusFound)
 523         }
 524         defer res.Body.Close()
 525         slurp, err := io.ReadAll(res.Body)
 526         if err != nil {
 527                 t.Fatal(err)
 528         }
 529         if string(slurp) != body {
 530                 t.Errorf("body = %q; want %q", slurp, body)
 531         }
 532 }
 533
 534 // Issues 17773 and 49281: don't follow a 3xx if the response doesn't
 535 // have a Location header.
 536 func TestClientRedirectNoLocation(t *testing.T) {
 537         for _, code := range []int{301, 308} {
 538                 t.Run(fmt.Sprint(code), func(t *testing.T) {
 539                         setParallel(t)
 540                         defer afterTest(t)
 541                         ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
 542                                 w.Header().Set("Foo", "Bar")
 543                                 w.WriteHeader(code)
 544                         }))
 545                         defer ts.Close()
 546                         c := ts.Client()
 547                         res, err := c.Get(ts.URL)
 548                         if err != nil {
 549                                 t.Fatal(err)
 550                         }
 551                         res.Body.Close()
 552                         if res.StatusCode != code {
 553                                 t.Errorf("status = %d; want %d", res.StatusCode, code)
 554                         }
 555                         if got := res.Header.Get("Foo"); got != "Bar" {
 556                                 t.Errorf("Foo header = %q; want Bar", got)
 557                         }
 558                 })
 559         }
 560 }
 561
 562 // Don't follow a 307/308 if we can't resent the request body.
 563 func TestClientRedirect308NoGetBody(t *testing.T) {
 564         setParallel(t)
 565         defer afterTest(t)
 566         const fakeURL = "https://localhost:1234/" // won't be hit
 567         ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
 568                 w.Header().Set("Location", fakeURL)
 569                 w.WriteHeader(308)
 570         }))
 571         defer ts.Close()
 572         req, err := NewRequest("POST", ts.URL, strings.NewReader("some body"))
 573         if err != nil {
 574                 t.Fatal(err)
 575         }
 576         c := ts.Client()
 577         req.GetBody = nil // so it can't rewind.
 578         res, err := c.Do(req)
 579         if err != nil {
 580                 t.Fatal(err)
 581         }
 582         res.Body.Close()
 583         if res.StatusCode != 308 {
 584                 t.Errorf("status = %d; want %d", res.StatusCode, 308)
 585         }
 586         if got := res.Header.Get("Location"); got != fakeURL {
 587                 t.Errorf("Location header = %q; want %q", got, fakeURL)
 588         }
 589 }
 590
 591 var expectedCookies = []*Cookie{
 592         {Name: "ChocolateChip", Value: "tasty"},
 593         {Name: "First", Value: "Hit"},
 594         {Name: "Second", Value: "Hit"},
 595 }
 596
 597 var echoCookiesRedirectHandler = HandlerFunc(func(w ResponseWriter, r *Request) {
 598         for _, cookie := range r.Cookies() {
 599                 SetCookie(w, cookie)
 600         }
 601         if r.URL.Path == "/" {
 602                 SetCookie(w, expectedCookies[1])
 603                 Redirect(w, r, "/second", StatusMovedPermanently)
 604         } else {
 605                 SetCookie(w, expectedCookies[2])
 606                 w.Write([]byte("hello"))
 607         }
 608 })
 609
 610 func TestClientSendsCookieFromJar(t *testing.T) {
 611         defer afterTest(t)
 612         tr := &recordingTransport{}
 613         client := &Client{Transport: tr}
 614         client.Jar = &TestJar{perURL: make(map[string][]*Cookie)}
 615         us := "http://dummy.faketld/"
 616         u, _ := url.Parse(us)
 617         client.Jar.SetCookies(u, expectedCookies)
 618
 619         client.Get(us) // Note: doesn't hit network
 620         matchReturnedCookies(t, expectedCookies, tr.req.Cookies())
 621
 622         client.Head(us) // Note: doesn't hit network
 623         matchReturnedCookies(t, expectedCookies, tr.req.Cookies())
 624
 625         client.Post(us, "text/plain", strings.NewReader("body")) // Note: doesn't hit network
 626         matchReturnedCookies(t, expectedCookies, tr.req.Cookies())
 627
 628         client.PostForm(us, url.Values{}) // Note: doesn't hit network
 629         matchReturnedCookies(t, expectedCookies, tr.req.Cookies())
 630
 631         req, _ := NewRequest("GET", us, nil)
 632         client.Do(req) // Note: doesn't hit network
 633         matchReturnedCookies(t, expectedCookies, tr.req.Cookies())
 634
 635         req, _ = NewRequest("POST", us, nil)
 636         client.Do(req) // Note: doesn't hit network
 637         matchReturnedCookies(t, expectedCookies, tr.req.Cookies())
 638 }
 639
 640 // Just enough correctness for our redirect tests. Uses the URL.Host as the
 641 // scope of all cookies.
 642 type TestJar struct {
 643         m      sync.Mutex
 644         perURL map[string][]*Cookie
 645 }
 646
 647 func (j *TestJar) SetCookies(u *url.URL, cookies []*Cookie) {
 648         j.m.Lock()
 649         defer j.m.Unlock()
 650         if j.perURL == nil {
 651                 j.perURL = make(map[string][]*Cookie)
 652         }
 653         j.perURL[u.Host] = cookies
 654 }
 655
 656 func (j *TestJar) Cookies(u *url.URL) []*Cookie {
 657         j.m.Lock()
 658         defer j.m.Unlock()
 659         return j.perURL[u.Host]
 660 }
 661
 662 func TestRedirectCookiesJar(t *testing.T) {
 663         setParallel(t)
 664         defer afterTest(t)
 665         var ts *httptest.Server
 666         ts = httptest.NewServer(echoCookiesRedirectHandler)
 667         defer ts.Close()
 668         c := ts.Client()
 669         c.Jar = new(TestJar)
 670         u, _ := url.Parse(ts.URL)
 671         c.Jar.SetCookies(u, []*Cookie{expectedCookies[0]})
 672         resp, err := c.Get(ts.URL)
 673         if err != nil {
 674                 t.Fatalf("Get: %v", err)
 675         }
 676         resp.Body.Close()
 677         matchReturnedCookies(t, expectedCookies, resp.Cookies())
 678 }
 679
 680 func matchReturnedCookies(t *testing.T, expected, given []*Cookie) {
 681         if len(given) != len(expected) {
 682                 t.Logf("Received cookies: %v", given)
 683                 t.Errorf("Expected %d cookies, got %d", len(expected), len(given))
 684         }
 685         for _, ec := range expected {
 686                 foundC := false
 687                 for _, c := range given {
 688                         if ec.Name == c.Name && ec.Value == c.Value {
 689                                 foundC = true
 690                                 break
 691                         }
 692                 }
 693                 if !foundC {
 694                         t.Errorf("Missing cookie %v", ec)
 695                 }
 696         }
 697 }
 698
 699 func TestJarCalls(t *testing.T) {
 700         defer afterTest(t)
 701         ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
 702                 pathSuffix := r.RequestURI[1:]
 703                 if r.RequestURI == "/nosetcookie" {
 704                         return // don't set cookies for this path
 705                 }
 706                 SetCookie(w, &Cookie{Name: "name" + pathSuffix, Value: "val" + pathSuffix})
 707                 if r.RequestURI == "/" {
 708                         Redirect(w, r, "http://secondhost.fake/secondpath", 302)
 709                 }
 710         }))
 711         defer ts.Close()
 712         jar := new(RecordingJar)
 713         c := ts.Client()
 714         c.Jar = jar
 715         c.Transport.(*Transport).Dial = func(_ string, _ string) (net.Conn, error) {
 716                 return net.Dial("tcp", ts.Listener.Addr().String())
 717         }
 718         _, err := c.Get("http://firsthost.fake/")
 719         if err != nil {
 720                 t.Fatal(err)
 721         }
 722         _, err = c.Get("http://firsthost.fake/nosetcookie")
 723         if err != nil {
 724                 t.Fatal(err)
 725         }
 726         got := jar.log.String()
 727         want := `Cookies("http://firsthost.fake/")
 728 SetCookie("http://firsthost.fake/", [name=val])
 729 Cookies("http://secondhost.fake/secondpath")
 730 SetCookie("http://secondhost.fake/secondpath", [namesecondpath=valsecondpath])
 731 Cookies("http://firsthost.fake/nosetcookie")
 732 `
 733         if got != want {
 734                 t.Errorf("Got Jar calls:\n%s\nWant:\n%s", got, want)
 735         }
 736 }
 737
 738 // RecordingJar keeps a log of calls made to it, without
 739 // tracking any cookies.
 740 type RecordingJar struct {
 741         mu  sync.Mutex
 742         log bytes.Buffer
 743 }
 744
 745 func (j *RecordingJar) SetCookies(u *url.URL, cookies []*Cookie) {
 746         j.logf("SetCookie(%q, %v)\n", u, cookies)
 747 }
 748
 749 func (j *RecordingJar) Cookies(u *url.URL) []*Cookie {
 750         j.logf("Cookies(%q)\n", u)
 751         return nil
 752 }
 753
 754 func (j *RecordingJar) logf(format string, args ...any) {
 755         j.mu.Lock()
 756         defer j.mu.Unlock()
 757         fmt.Fprintf(&j.log, format, args...)
 758 }
 759
 760 func TestStreamingGet_h1(t *testing.T) { testStreamingGet(t, h1Mode) }
 761 func TestStreamingGet_h2(t *testing.T) { testStreamingGet(t, h2Mode) }
 762
 763 func testStreamingGet(t *testing.T, h2 bool) {
 764         defer afterTest(t)
 765         say := make(chan string)
 766         cst := newClientServerTest(t, h2, HandlerFunc(func(w ResponseWriter, r *Request) {
 767                 w.(Flusher).Flush()
 768                 for str := range say {
 769                         w.Write([]byte(str))
 770                         w.(Flusher).Flush()
 771                 }
 772         }))
 773         defer cst.close()
 774
 775         c := cst.c
 776         res, err := c.Get(cst.ts.URL)
 777         if err != nil {
 778                 t.Fatal(err)
 779         }
 780         var buf [10]byte
 781         for _, str := range []string{"i", "am", "also", "known", "as", "comet"} {
 782                 say <- str
 783                 n, err := io.ReadFull(res.Body, buf[0:len(str)])
 784                 if err != nil {
 785                         t.Fatalf("ReadFull on %q: %v", str, err)
 786                 }
 787                 if n != len(str) {
 788                         t.Fatalf("Receiving %q, only read %d bytes", str, n)
 789                 }
 790                 got := string(buf[0:n])
 791                 if got != str {
 792                         t.Fatalf("Expected %q, got %q", str, got)
 793                 }
 794         }
 795         close(say)
 796         _, err = io.ReadFull(res.Body, buf[0:1])
 797         if err != io.EOF {
 798                 t.Fatalf("at end expected EOF, got %v", err)
 799         }
 800 }
 801
 802 type writeCountingConn struct {
 803         net.Conn
 804         count *int
 805 }
 806
 807 func (c *writeCountingConn) Write(p []byte) (int, error) {
 808         *c.count++
 809         return c.Conn.Write(p)
 810 }
 811
 812 // TestClientWrites verifies that client requests are buffered and we
 813 // don't send a TCP packet per line of the http request + body.
 814 func TestClientWrites(t *testing.T) {
 815         defer afterTest(t)
 816         ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
 817         }))
 818         defer ts.Close()
 819
 820         writes := 0
 821         dialer := func(netz string, addr string) (net.Conn, error) {
 822                 c, err := net.Dial(netz, addr)
 823                 if err == nil {
 824                         c = &writeCountingConn{c, &writes}
 825                 }
 826                 return c, err
 827         }
 828         c := ts.Client()
 829         c.Transport.(*Transport).Dial = dialer
 830
 831         _, err := c.Get(ts.URL)
 832         if err != nil {
 833                 t.Fatal(err)
 834         }
 835         if writes != 1 {
 836                 t.Errorf("Get request did %d Write calls, want 1", writes)
 837         }
 838
 839         writes = 0
 840         _, err = c.PostForm(ts.URL, url.Values{"foo": {"bar"}})
 841         if err != nil {
 842                 t.Fatal(err)
 843         }
 844         if writes != 1 {
 845                 t.Errorf("Post request did %d Write calls, want 1", writes)
 846         }
 847 }
 848
 849 func TestClientInsecureTransport(t *testing.T) {
 850         setParallel(t)
 851         defer afterTest(t)
 852         ts := httptest.NewTLSServer(HandlerFunc(func(w ResponseWriter, r *Request) {
 853                 w.Write([]byte("Hello"))
 854         }))
 855         errc := make(chanWriter, 10) // but only expecting 1
 856         ts.Config.ErrorLog = log.New(errc, "", 0)
 857         defer ts.Close()
 858
 859         // TODO(bradfitz): add tests for skipping hostname checks too?
 860         // would require a new cert for testing, and probably
 861         // redundant with these tests.
 862         c := ts.Client()
 863         for _, insecure := range []bool{true, false} {
 864                 c.Transport.(*Transport).TLSClientConfig = &tls.Config{
 865                         InsecureSkipVerify: insecure,
 866                 }
 867                 res, err := c.Get(ts.URL)
 868                 if (err == nil) != insecure {
 869                         t.Errorf("insecure=%v: got unexpected err=%v", insecure, err)
 870                 }
 871                 if res != nil {
 872                         res.Body.Close()
 873                 }
 874         }
 875
 876         select {
 877         case v := <-errc:
 878                 if !strings.Contains(v, "TLS handshake error") {
 879                         t.Errorf("expected an error log message containing 'TLS handshake error'; got %q", v)
 880                 }
 881         case <-time.After(5 * time.Second):
 882                 t.Errorf("timeout waiting for logged error")
 883         }
 884
 885 }
 886
 887 func TestClientErrorWithRequestURI(t *testing.T) {
 888         defer afterTest(t)
 889         req, _ := NewRequest("GET", "http://localhost:1234/", nil)
 890         req.RequestURI = "/this/field/is/illegal/and/should/error/"
 891         _, err := DefaultClient.Do(req)
 892         if err == nil {
 893                 t.Fatalf("expected an error")
 894         }
 895         if !strings.Contains(err.Error(), "RequestURI") {
 896                 t.Errorf("wanted error mentioning RequestURI; got error: %v", err)
 897         }
 898 }
 899
 900 func TestClientWithCorrectTLSServerName(t *testing.T) {
 901         defer afterTest(t)
 902
 903         const serverName = "example.com"
 904         ts := httptest.NewTLSServer(HandlerFunc(func(w ResponseWriter, r *Request) {
 905                 if r.TLS.ServerName != serverName {
 906                         t.Errorf("expected client to set ServerName %q, got: %q", serverName, r.TLS.ServerName)
 907                 }
 908         }))
 909         defer ts.Close()
 910
 911         c := ts.Client()
 912         c.Transport.(*Transport).TLSClientConfig.ServerName = serverName
 913         if _, err := c.Get(ts.URL); err != nil {
 914                 t.Fatalf("expected successful TLS connection, got error: %v", err)
 915         }
 916 }
 917
 918 func TestClientWithIncorrectTLSServerName(t *testing.T) {
 919         defer afterTest(t)
 920         ts := httptest.NewTLSServer(HandlerFunc(func(w ResponseWriter, r *Request) {}))
 921         defer ts.Close()
 922         errc := make(chanWriter, 10) // but only expecting 1
 923         ts.Config.ErrorLog = log.New(errc, "", 0)
 924
 925         c := ts.Client()
 926         c.Transport.(*Transport).TLSClientConfig.ServerName = "badserver"
 927         _, err := c.Get(ts.URL)
 928         if err == nil {
 929                 t.Fatalf("expected an error")
 930         }
 931         if !strings.Contains(err.Error(), "127.0.0.1") || !strings.Contains(err.Error(), "badserver") {
 932                 t.Errorf("wanted error mentioning 127.0.0.1 and badserver; got error: %v", err)
 933         }
 934         select {
 935         case v := <-errc:
 936                 if !strings.Contains(v, "TLS handshake error") {
 937                         t.Errorf("expected an error log message containing 'TLS handshake error'; got %q", v)
 938                 }
 939         case <-time.After(5 * time.Second):
 940                 t.Errorf("timeout waiting for logged error")
 941         }
 942 }
 943
 944 // Test for golang.org/issue/5829; the Transport should respect TLSClientConfig.ServerName
 945 // when not empty.
 946 //
 947 // tls.Config.ServerName (non-empty, set to "example.com") takes
 948 // precedence over "some-other-host.tld" which previously incorrectly
 949 // took precedence. We don't actually connect to (or even resolve)
 950 // "some-other-host.tld", though, because of the Transport.Dial hook.
 951 //
 952 // The httptest.Server has a cert with "example.com" as its name.
 953 func TestTransportUsesTLSConfigServerName(t *testing.T) {
 954         defer afterTest(t)
 955         ts := httptest.NewTLSServer(HandlerFunc(func(w ResponseWriter, r *Request) {
 956                 w.Write([]byte("Hello"))
 957         }))
 958         defer ts.Close()
 959
 960         c := ts.Client()
 961         tr := c.Transport.(*Transport)
 962         tr.TLSClientConfig.ServerName = "example.com" // one of httptest's Server cert names
 963         tr.Dial = func(netw, addr string) (net.Conn, error) {
 964                 return net.Dial(netw, ts.Listener.Addr().String())
 965         }
 966         res, err := c.Get("https://some-other-host.tld/")
 967         if err != nil {
 968                 t.Fatal(err)
 969         }
 970         res.Body.Close()
 971 }
 972
 973 func TestResponseSetsTLSConnectionState(t *testing.T) {
 974         defer afterTest(t)
 975         ts := httptest.NewTLSServer(HandlerFunc(func(w ResponseWriter, r *Request) {
 976                 w.Write([]byte("Hello"))
 977         }))
 978         defer ts.Close()
 979
 980         c := ts.Client()
 981         tr := c.Transport.(*Transport)
 982         tr.TLSClientConfig.CipherSuites = []uint16{tls.TLS_RSA_WITH_3DES_EDE_CBC_SHA}
 983         tr.TLSClientConfig.MaxVersion = tls.VersionTLS12 // to get to pick the cipher suite
 984         tr.Dial = func(netw, addr string) (net.Conn, error) {
 985                 return net.Dial(netw, ts.Listener.Addr().String())
 986         }
 987         res, err := c.Get("https://example.com/")
 988         if err != nil {
 989                 t.Fatal(err)
 990         }
 991         defer res.Body.Close()
 992         if res.TLS == nil {
 993                 t.Fatal("Response didn't set TLS Connection State.")
 994         }
 995         if got, want := res.TLS.CipherSuite, tls.TLS_RSA_WITH_3DES_EDE_CBC_SHA; got != want {
 996                 t.Errorf("TLS Cipher Suite = %d; want %d", got, want)
 997         }
 998 }
 999
1000 // Check that an HTTPS client can interpret a particular TLS error
1001 // to determine that the server is speaking HTTP.
1002 // See golang.org/issue/11111.
1003 func TestHTTPSClientDetectsHTTPServer(t *testing.T) {
1004         defer afterTest(t)
1005         ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {}))
1006         ts.Config.ErrorLog = quietLog
1007         defer ts.Close()
1008
1009         _, err := Get(strings.Replace(ts.URL, "http", "https", 1))
1010         if got := err.Error(); !strings.Contains(got, "HTTP response to HTTPS client") {
1011                 t.Fatalf("error = %q; want error indicating HTTP response to HTTPS request", got)
1012         }
1013 }
1014
1015 // Verify Response.ContentLength is populated. https://golang.org/issue/4126
1016 func TestClientHeadContentLength_h1(t *testing.T) {
1017         testClientHeadContentLength(t, h1Mode)
1018 }
1019
1020 func TestClientHeadContentLength_h2(t *testing.T) {
1021         testClientHeadContentLength(t, h2Mode)
1022 }
1023
1024 func testClientHeadContentLength(t *testing.T, h2 bool) {
1025         defer afterTest(t)
1026         cst := newClientServerTest(t, h2, HandlerFunc(func(w ResponseWriter, r *Request) {
1027                 if v := r.FormValue("cl"); v != "" {
1028                         w.Header().Set("Content-Length", v)
1029                 }
1030         }))
1031         defer cst.close()
1032         tests := []struct {
1033                 suffix string
1034                 want   int64
1035         }{
1036                 {"/?cl=1234", 1234},
1037                 {"/?cl=0", 0},
1038                 {"", -1},
1039         }
1040         for _, tt := range tests {
1041                 req, _ := NewRequest("HEAD", cst.ts.URL+tt.suffix, nil)
1042                 res, err := cst.c.Do(req)
1043                 if err != nil {
1044                         t.Fatal(err)
1045                 }
1046                 if res.ContentLength != tt.want {
1047                         t.Errorf("Content-Length = %d; want %d", res.ContentLength, tt.want)
1048                 }
1049                 bs, err := io.ReadAll(res.Body)
1050                 if err != nil {
1051                         t.Fatal(err)
1052                 }
1053                 if len(bs) != 0 {
1054                         t.Errorf("Unexpected content: %q", bs)
1055                 }
1056         }
1057 }
1058
1059 func TestEmptyPasswordAuth(t *testing.T) {
1060         setParallel(t)
1061         defer afterTest(t)
1062         gopher := "gopher"
1063         ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
1064                 auth := r.Header.Get("Authorization")
1065                 if strings.HasPrefix(auth, "Basic ") {
1066                         encoded := auth[6:]
1067                         decoded, err := base64.StdEncoding.DecodeString(encoded)
1068                         if err != nil {
1069                                 t.Fatal(err)
1070                         }
1071                         expected := gopher + ":"
1072                         s := string(decoded)
1073                         if expected != s {
1074                                 t.Errorf("Invalid Authorization header. Got %q, wanted %q", s, expected)
1075                         }
1076                 } else {
1077                         t.Errorf("Invalid auth %q", auth)
1078                 }
1079         }))
1080         defer ts.Close()
1081         req, err := NewRequest("GET", ts.URL, nil)
1082         if err != nil {
1083                 t.Fatal(err)
1084         }
1085         req.URL.User = url.User(gopher)
1086         c := ts.Client()
1087         resp, err := c.Do(req)
1088         if err != nil {
1089                 t.Fatal(err)
1090         }
1091         defer resp.Body.Close()
1092 }
1093
1094 func TestBasicAuth(t *testing.T) {
1095         defer afterTest(t)
1096         tr := &recordingTransport{}
1097         client := &Client{Transport: tr}
1098
1099         url := "http://My%20User:My%20Pass@dummy.faketld/"
1100         expected := "My User:My Pass"
1101         client.Get(url)
1102
1103         if tr.req.Method != "GET" {
1104                 t.Errorf("got method %q, want %q", tr.req.Method, "GET")
1105         }
1106         if tr.req.URL.String() != url {
1107                 t.Errorf("got URL %q, want %q", tr.req.URL.String(), url)
1108         }
1109         if tr.req.Header == nil {
1110                 t.Fatalf("expected non-nil request Header")
1111         }
1112         auth := tr.req.Header.Get("Authorization")
1113         if strings.HasPrefix(auth, "Basic ") {
1114                 encoded := auth[6:]
1115                 decoded, err := base64.StdEncoding.DecodeString(encoded)
1116                 if err != nil {
1117                         t.Fatal(err)
1118                 }
1119                 s := string(decoded)
1120                 if expected != s {
1121                         t.Errorf("Invalid Authorization header. Got %q, wanted %q", s, expected)
1122                 }
1123         } else {
1124                 t.Errorf("Invalid auth %q", auth)
1125         }
1126 }
1127
1128 func TestBasicAuthHeadersPreserved(t *testing.T) {
1129         defer afterTest(t)
1130         tr := &recordingTransport{}
1131         client := &Client{Transport: tr}
1132
1133         // If Authorization header is provided, username in URL should not override it
1134         url := "http://My%20User@dummy.faketld/"
1135         req, err := NewRequest("GET", url, nil)
1136         if err != nil {
1137                 t.Fatal(err)
1138         }
1139         req.SetBasicAuth("My User", "My Pass")
1140         expected := "My User:My Pass"
1141         client.Do(req)
1142
1143         if tr.req.Method != "GET" {
1144                 t.Errorf("got method %q, want %q", tr.req.Method, "GET")
1145         }
1146         if tr.req.URL.String() != url {
1147                 t.Errorf("got URL %q, want %q", tr.req.URL.String(), url)
1148         }
1149         if tr.req.Header == nil {
1150                 t.Fatalf("expected non-nil request Header")
1151         }
1152         auth := tr.req.Header.Get("Authorization")
1153         if strings.HasPrefix(auth, "Basic ") {
1154                 encoded := auth[6:]
1155                 decoded, err := base64.StdEncoding.DecodeString(encoded)
1156                 if err != nil {
1157                         t.Fatal(err)
1158                 }
1159                 s := string(decoded)
1160                 if expected != s {
1161                         t.Errorf("Invalid Authorization header. Got %q, wanted %q", s, expected)
1162                 }
1163         } else {
1164                 t.Errorf("Invalid auth %q", auth)
1165         }
1166
1167 }
1168
1169 func TestStripPasswordFromError(t *testing.T) {
1170         client := &Client{Transport: &recordingTransport{}}
1171         testCases := []struct {
1172                 desc string
1173                 in   string
1174                 out  string
1175         }{
1176                 {
1177                         desc: "Strip password from error message",
1178                         in:   "http://user:password@dummy.faketld/",
1179                         out:  `Get "http://user:***@dummy.faketld/": dummy impl`,
1180                 },
1181                 {
1182                         desc: "Don't Strip password from domain name",
1183                         in:   "http://user:password@password.faketld/",
1184                         out:  `Get "http://user:***@password.faketld/": dummy impl`,
1185                 },
1186                 {
1187                         desc: "Don't Strip password from path",
1188                         in:   "http://user:password@dummy.faketld/password",
1189                         out:  `Get "http://user:***@dummy.faketld/password": dummy impl`,
1190                 },
1191                 {
1192                         desc: "Strip escaped password",
1193                         in:   "http://user:pa%2Fssword@dummy.faketld/",
1194                         out:  `Get "http://user:***@dummy.faketld/": dummy impl`,
1195                 },
1196         }
1197         for _, tC := range testCases {
1198                 t.Run(tC.desc, func(t *testing.T) {
1199                         _, err := client.Get(tC.in)
1200                         if err.Error() != tC.out {
1201                                 t.Errorf("Unexpected output for %q: expected %q, actual %q",
1202                                         tC.in, tC.out, err.Error())
1203                         }
1204                 })
1205         }
1206 }
1207
1208 func TestClientTimeout_h1(t *testing.T) { testClientTimeout(t, h1Mode) }
1209 func TestClientTimeout_h2(t *testing.T) { testClientTimeout(t, h2Mode) }
1210
1211 func testClientTimeout(t *testing.T, h2 bool) {
1212         setParallel(t)
1213         defer afterTest(t)
1214
1215         var (
1216                 mu           sync.Mutex
1217                 nonce        string // a unique per-request string
1218                 sawSlowNonce bool   // true if the handler saw /slow?nonce=<nonce>
1219         )
1220         cst := newClientServerTest(t, h2, HandlerFunc(func(w ResponseWriter, r *Request) {
1221                 _ = r.ParseForm()
1222                 if r.URL.Path == "/" {
1223                         Redirect(w, r, "/slow?nonce="+r.Form.Get("nonce"), StatusFound)
1224                         return
1225                 }
1226                 if r.URL.Path == "/slow" {
1227                         mu.Lock()
1228                         if r.Form.Get("nonce") == nonce {
1229                                 sawSlowNonce = true
1230                         } else {
1231                                 t.Logf("mismatched nonce: received %s, want %s", r.Form.Get("nonce"), nonce)
1232                         }
1233                         mu.Unlock()
1234
1235                         w.Write([]byte("Hello"))
1236                         w.(Flusher).Flush()
1237                         <-r.Context().Done()
1238                         return
1239                 }
1240         }))
1241         defer cst.close()
1242
1243         // Try to trigger a timeout after reading part of the response body.
1244         // The initial timeout is emprically usually long enough on a decently fast
1245         // machine, but if we undershoot we'll retry with exponentially longer
1246         // timeouts until the test either passes or times out completely.
1247         // This keeps the test reasonably fast in the typical case but allows it to
1248         // also eventually succeed on arbitrarily slow machines.
1249         timeout := 10 * time.Millisecond
1250         nextNonce := 0
1251         for ; ; timeout *= 2 {
1252                 if timeout <= 0 {
1253                         // The only way we can feasibly hit this while the test is running is if
1254                         // the request fails without actually waiting for the timeout to occur.
1255                         t.Fatalf("timeout overflow")
1256                 }
1257                 if deadline, ok := t.Deadline(); ok && !time.Now().Add(timeout).Before(deadline) {
1258                         t.Fatalf("failed to produce expected timeout before test deadline")
1259                 }
1260                 t.Logf("attempting test with timeout %v", timeout)
1261                 cst.c.Timeout = timeout
1262
1263                 mu.Lock()
1264                 nonce = fmt.Sprint(nextNonce)
1265                 nextNonce++
1266                 sawSlowNonce = false
1267                 mu.Unlock()
1268                 res, err := cst.c.Get(cst.ts.URL + "/?nonce=" + nonce)
1269                 if err != nil {
1270                         if strings.Contains(err.Error(), "Client.Timeout") {
1271                                 // Timed out before handler could respond.
1272                                 t.Logf("timeout before response received")
1273                                 continue
1274                         }
1275                         if runtime.GOOS == "windows" && strings.HasPrefix(runtime.GOARCH, "arm") {
1276                                 testenv.SkipFlaky(t, 43120)
1277                         }
1278                         t.Fatal(err)
1279                 }
1280
1281                 mu.Lock()
1282                 ok := sawSlowNonce
1283                 mu.Unlock()
1284                 if !ok {
1285                         t.Fatal("handler never got /slow request, but client returned response")
1286                 }
1287
1288                 _, err = io.ReadAll(res.Body)
1289                 res.Body.Close()
1290
1291                 if err == nil {
1292                         t.Fatal("expected error from ReadAll")
1293                 }
1294                 ne, ok := err.(net.Error)
1295                 if !ok {
1296                         t.Errorf("error value from ReadAll was %T; expected some net.Error", err)
1297                 } else if !ne.Timeout() {
1298                         t.Errorf("net.Error.Timeout = false; want true")
1299                 }
1300                 if got := ne.Error(); !strings.Contains(got, "(Client.Timeout") {
1301                         if runtime.GOOS == "windows" && strings.HasPrefix(runtime.GOARCH, "arm") {
1302                                 testenv.SkipFlaky(t, 43120)
1303                         }
1304                         t.Errorf("error string = %q; missing timeout substring", got)
1305                 }
1306
1307                 break
1308         }
1309 }
1310
1311 func TestClientTimeout_Headers_h1(t *testing.T) { testClientTimeout_Headers(t, h1Mode) }
1312 func TestClientTimeout_Headers_h2(t *testing.T) { testClientTimeout_Headers(t, h2Mode) }
1313
1314 // Client.Timeout firing before getting to the body
1315 func testClientTimeout_Headers(t *testing.T, h2 bool) {
1316         setParallel(t)
1317         defer afterTest(t)
1318         donec := make(chan bool, 1)
1319         cst := newClientServerTest(t, h2, HandlerFunc(func(w ResponseWriter, r *Request) {
1320                 <-donec
1321         }), optQuietLog)
1322         defer cst.close()
1323         // Note that we use a channel send here and not a close.
1324         // The race detector doesn't know that we're waiting for a timeout
1325         // and thinks that the waitgroup inside httptest.Server is added to concurrently
1326         // with us closing it. If we timed out immediately, we could close the testserver
1327         // before we entered the handler. We're not timing out immediately and there's
1328         // no way we would be done before we entered the handler, but the race detector
1329         // doesn't know this, so synchronize explicitly.
1330         defer func() { donec <- true }()
1331
1332         cst.c.Timeout = 5 * time.Millisecond
1333         res, err := cst.c.Get(cst.ts.URL)
1334         if err == nil {
1335                 res.Body.Close()
1336                 t.Fatal("got response from Get; expected error")
1337         }
1338         if _, ok := err.(*url.Error); !ok {
1339                 t.Fatalf("Got error of type %T; want *url.Error", err)
1340         }
1341         ne, ok := err.(net.Error)
1342         if !ok {
1343                 t.Fatalf("Got error of type %T; want some net.Error", err)
1344         }
1345         if !ne.Timeout() {
1346                 t.Error("net.Error.Timeout = false; want true")
1347         }
1348         if got := ne.Error(); !strings.Contains(got, "Client.Timeout exceeded") {
1349                 if runtime.GOOS == "windows" && strings.HasPrefix(runtime.GOARCH, "arm") {
1350                         testenv.SkipFlaky(t, 43120)
1351                 }
1352                 t.Errorf("error string = %q; missing timeout substring", got)
1353         }
1354 }
1355
1356 // Issue 16094: if Client.Timeout is set but not hit, a Timeout error shouldn't be
1357 // returned.
1358 func TestClientTimeoutCancel(t *testing.T) {
1359         setParallel(t)
1360         defer afterTest(t)
1361
1362         testDone := make(chan struct{})
1363         ctx, cancel := context.WithCancel(context.Background())
1364
1365         cst := newClientServerTest(t, h1Mode, HandlerFunc(func(w ResponseWriter, r *Request) {
1366                 w.(Flusher).Flush()
1367                 <-testDone
1368         }))
1369         defer cst.close()
1370         defer close(testDone)
1371
1372         cst.c.Timeout = 1 * time.Hour
1373         req, _ := NewRequest("GET", cst.ts.URL, nil)
1374         req.Cancel = ctx.Done()
1375         res, err := cst.c.Do(req)
1376         if err != nil {
1377                 t.Fatal(err)
1378         }
1379         cancel()
1380         _, err = io.Copy(io.Discard, res.Body)
1381         if err != ExportErrRequestCanceled {
1382                 t.Fatalf("error = %v; want errRequestCanceled", err)
1383         }
1384 }
1385
1386 func TestClientTimeoutDoesNotExpire_h1(t *testing.T) { testClientTimeoutDoesNotExpire(t, h1Mode) }
1387 func TestClientTimeoutDoesNotExpire_h2(t *testing.T) { testClientTimeoutDoesNotExpire(t, h2Mode) }
1388
1389 // Issue 49366: if Client.Timeout is set but not hit, no error should be returned.
1390 func testClientTimeoutDoesNotExpire(t *testing.T, h2 bool) {
1391         setParallel(t)
1392         defer afterTest(t)
1393
1394         cst := newClientServerTest(t, h2, HandlerFunc(func(w ResponseWriter, r *Request) {
1395                 w.Write([]byte("body"))
1396         }))
1397         defer cst.close()
1398
1399         cst.c.Timeout = 1 * time.Hour
1400         req, _ := NewRequest("GET", cst.ts.URL, nil)
1401         res, err := cst.c.Do(req)
1402         if err != nil {
1403                 t.Fatal(err)
1404         }
1405         if _, err = io.Copy(io.Discard, res.Body); err != nil {
1406                 t.Fatalf("io.Copy(io.Discard, res.Body) = %v, want nil", err)
1407         }
1408         if err = res.Body.Close(); err != nil {
1409                 t.Fatalf("res.Body.Close() = %v, want nil", err)
1410         }
1411 }
1412
1413 func TestClientRedirectEatsBody_h1(t *testing.T) { testClientRedirectEatsBody(t, h1Mode) }
1414 func TestClientRedirectEatsBody_h2(t *testing.T) { testClientRedirectEatsBody(t, h2Mode) }
1415 func testClientRedirectEatsBody(t *testing.T, h2 bool) {
1416         setParallel(t)
1417         defer afterTest(t)
1418         saw := make(chan string, 2)
1419         cst := newClientServerTest(t, h2, HandlerFunc(func(w ResponseWriter, r *Request) {
1420                 saw <- r.RemoteAddr
1421                 if r.URL.Path == "/" {
1422                         Redirect(w, r, "/foo", StatusFound) // which includes a body
1423                 }
1424         }))
1425         defer cst.close()
1426
1427         res, err := cst.c.Get(cst.ts.URL)
1428         if err != nil {
1429                 t.Fatal(err)
1430         }
1431         _, err = io.ReadAll(res.Body)
1432         res.Body.Close()
1433         if err != nil {
1434                 t.Fatal(err)
1435         }
1436
1437         var first string
1438         select {
1439         case first = <-saw:
1440         default:
1441                 t.Fatal("server didn't see a request")
1442         }
1443
1444         var second string
1445         select {
1446         case second = <-saw:
1447         default:
1448                 t.Fatal("server didn't see a second request")
1449         }
1450
1451         if first != second {
1452                 t.Fatal("server saw different client ports before & after the redirect")
1453         }
1454 }
1455
1456 // eofReaderFunc is an io.Reader that runs itself, and then returns io.EOF.
1457 type eofReaderFunc func()
1458
1459 func (f eofReaderFunc) Read(p []byte) (n int, err error) {
1460         f()
1461         return 0, io.EOF
1462 }
1463
1464 func TestReferer(t *testing.T) {
1465         tests := []struct {
1466                 lastReq, newReq string // from -> to URLs
1467                 want            string
1468         }{
1469                 // don't send user:
1470                 {"http://gopher@test.com", "http://link.com", "http://test.com"},
1471                 {"https://gopher@test.com", "https://link.com", "https://test.com"},
1472
1473                 // don't send a user and password:
1474                 {"http://gopher:go@test.com", "http://link.com", "http://test.com"},
1475                 {"https://gopher:go@test.com", "https://link.com", "https://test.com"},
1476
1477                 // nothing to do:
1478                 {"http://test.com", "http://link.com", "http://test.com"},
1479                 {"https://test.com", "https://link.com", "https://test.com"},
1480
1481                 // https to http doesn't send a referer:
1482                 {"https://test.com", "http://link.com", ""},
1483                 {"https://gopher:go@test.com", "http://link.com", ""},
1484         }
1485         for _, tt := range tests {
1486                 l, err := url.Parse(tt.lastReq)
1487                 if err != nil {
1488                         t.Fatal(err)
1489                 }
1490                 n, err := url.Parse(tt.newReq)
1491                 if err != nil {
1492                         t.Fatal(err)
1493                 }
1494                 r := ExportRefererForURL(l, n)
1495                 if r != tt.want {
1496                         t.Errorf("refererForURL(%q, %q) = %q; want %q", tt.lastReq, tt.newReq, r, tt.want)
1497                 }
1498         }
1499 }
1500
1501 // issue15577Tripper returns a Response with a redirect response
1502 // header and doesn't populate its Response.Request field.
1503 type issue15577Tripper struct{}
1504
1505 func (issue15577Tripper) RoundTrip(*Request) (*Response, error) {
1506         resp := &Response{
1507                 StatusCode: 303,
1508                 Header:     map[string][]string{"Location": {"http://www.example.com/"}},
1509                 Body:       io.NopCloser(strings.NewReader("")),
1510         }
1511         return resp, nil
1512 }
1513
1514 // Issue 15577: don't assume the roundtripper's response populates its Request field.
1515 func TestClientRedirectResponseWithoutRequest(t *testing.T) {
1516         c := &Client{
1517                 CheckRedirect: func(*Request, []*Request) error { return fmt.Errorf("no redirects!") },
1518                 Transport:     issue15577Tripper{},
1519         }
1520         // Check that this doesn't crash:
1521         c.Get("http://dummy.tld")
1522 }
1523
1524 // Issue 4800: copy (some) headers when Client follows a redirect.
1525 func TestClientCopyHeadersOnRedirect(t *testing.T) {
1526         const (
1527                 ua   = "some-agent/1.2"
1528                 xfoo = "foo-val"
1529         )
1530         var ts2URL string
1531         ts1 := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
1532                 want := Header{
1533                         "User-Agent":      []string{ua},
1534                         "X-Foo":           []string{xfoo},
1535                         "Referer":         []string{ts2URL},
1536                         "Accept-Encoding": []string{"gzip"},
1537                 }
1538                 if !reflect.DeepEqual(r.Header, want) {
1539                         t.Errorf("Request.Header = %#v; want %#v", r.Header, want)
1540                 }
1541                 if t.Failed() {
1542                         w.Header().Set("Result", "got errors")
1543                 } else {
1544                         w.Header().Set("Result", "ok")
1545                 }
1546         }))
1547         defer ts1.Close()
1548         ts2 := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
1549                 Redirect(w, r, ts1.URL, StatusFound)
1550         }))
1551         defer ts2.Close()
1552         ts2URL = ts2.URL
1553
1554         c := ts1.Client()
1555         c.CheckRedirect = func(r *Request, via []*Request) error {
1556                 want := Header{
1557                         "User-Agent": []string{ua},
1558                         "X-Foo":      []string{xfoo},
1559                         "Referer":    []string{ts2URL},
1560                 }
1561                 if !reflect.DeepEqual(r.Header, want) {
1562                         t.Errorf("CheckRedirect Request.Header = %#v; want %#v", r.Header, want)
1563                 }
1564                 return nil
1565         }
1566
1567         req, _ := NewRequest("GET", ts2.URL, nil)
1568         req.Header.Add("User-Agent", ua)
1569         req.Header.Add("X-Foo", xfoo)
1570         req.Header.Add("Cookie", "foo=bar")
1571         req.Header.Add("Authorization", "secretpassword")
1572         res, err := c.Do(req)
1573         if err != nil {
1574                 t.Fatal(err)
1575         }
1576         defer res.Body.Close()
1577         if res.StatusCode != 200 {
1578                 t.Fatal(res.Status)
1579         }
1580         if got := res.Header.Get("Result"); got != "ok" {
1581                 t.Errorf("result = %q; want ok", got)
1582         }
1583 }
1584
1585 // Issue 22233: copy host when Client follows a relative redirect.
1586 func TestClientCopyHostOnRedirect(t *testing.T) {
1587         // Virtual hostname: should not receive any request.
1588         virtual := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
1589                 t.Errorf("Virtual host received request %v", r.URL)
1590                 w.WriteHeader(403)
1591                 io.WriteString(w, "should not see this response")
1592         }))
1593         defer virtual.Close()
1594         virtualHost := strings.TrimPrefix(virtual.URL, "http://")
1595         t.Logf("Virtual host is %v", virtualHost)
1596
1597         // Actual hostname: should not receive any request.
1598         const wantBody = "response body"
1599         var tsURL string
1600         var tsHost string
1601         ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
1602                 switch r.URL.Path {
1603                 case "/":
1604                         // Relative redirect.
1605                         if r.Host != virtualHost {
1606                                 t.Errorf("Serving /: Request.Host = %#v; want %#v", r.Host, virtualHost)
1607                                 w.WriteHeader(404)
1608                                 return
1609                         }
1610                         w.Header().Set("Location", "/hop")
1611                         w.WriteHeader(302)
1612                 case "/hop":
1613                         // Absolute redirect.
1614                         if r.Host != virtualHost {
1615                                 t.Errorf("Serving /hop: Request.Host = %#v; want %#v", r.Host, virtualHost)
1616                                 w.WriteHeader(404)
1617                                 return
1618                         }
1619                         w.Header().Set("Location", tsURL+"/final")
1620                         w.WriteHeader(302)
1621                 case "/final":
1622                         if r.Host != tsHost {
1623                                 t.Errorf("Serving /final: Request.Host = %#v; want %#v", r.Host, tsHost)
1624                                 w.WriteHeader(404)
1625                                 return
1626                         }
1627                         w.WriteHeader(200)
1628                         io.WriteString(w, wantBody)
1629                 default:
1630                         t.Errorf("Serving unexpected path %q", r.URL.Path)
1631                         w.WriteHeader(404)
1632                 }
1633         }))
1634         defer ts.Close()
1635         tsURL = ts.URL
1636         tsHost = strings.TrimPrefix(ts.URL, "http://")
1637         t.Logf("Server host is %v", tsHost)
1638
1639         c := ts.Client()
1640         req, _ := NewRequest("GET", ts.URL, nil)
1641         req.Host = virtualHost
1642         resp, err := c.Do(req)
1643         if err != nil {
1644                 t.Fatal(err)
1645         }
1646         defer resp.Body.Close()
1647         if resp.StatusCode != 200 {
1648                 t.Fatal(resp.Status)
1649         }
1650         if got, err := io.ReadAll(resp.Body); err != nil || string(got) != wantBody {
1651                 t.Errorf("body = %q; want %q", got, wantBody)
1652         }
1653 }
1654
1655 // Issue 17494: cookies should be altered when Client follows redirects.
1656 func TestClientAltersCookiesOnRedirect(t *testing.T) {
1657         cookieMap := func(cs []*Cookie) map[string][]string {
1658                 m := make(map[string][]string)
1659                 for _, c := range cs {
1660                         m[c.Name] = append(m[c.Name], c.Value)
1661                 }
1662                 return m
1663         }
1664
1665         ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
1666                 var want map[string][]string
1667                 got := cookieMap(r.Cookies())
1668
1669                 c, _ := r.Cookie("Cycle")
1670                 switch c.Value {
1671                 case "0":
1672                         want = map[string][]string{
1673                                 "Cookie1": {"OldValue1a", "OldValue1b"},
1674                                 "Cookie2": {"OldValue2"},
1675                                 "Cookie3": {"OldValue3a", "OldValue3b"},
1676                                 "Cookie4": {"OldValue4"},
1677                                 "Cycle":   {"0"},
1678                         }
1679                         SetCookie(w, &Cookie{Name: "Cycle", Value: "1", Path: "/"})
1680                         SetCookie(w, &Cookie{Name: "Cookie2", Path: "/", MaxAge: -1}) // Delete cookie from Header
1681                         Redirect(w, r, "/", StatusFound)
1682                 case "1":
1683                         want = map[string][]string{
1684                                 "Cookie1": {"OldValue1a", "OldValue1b"},
1685                                 "Cookie3": {"OldValue3a", "OldValue3b"},
1686                                 "Cookie4": {"OldValue4"},
1687                                 "Cycle":   {"1"},
1688                         }
1689                         SetCookie(w, &Cookie{Name: "Cycle", Value: "2", Path: "/"})
1690                         SetCookie(w, &Cookie{Name: "Cookie3", Value: "NewValue3", Path: "/"}) // Modify cookie in Header
1691                         SetCookie(w, &Cookie{Name: "Cookie4", Value: "NewValue4", Path: "/"}) // Modify cookie in Jar
1692                         Redirect(w, r, "/", StatusFound)
1693                 case "2":
1694                         want = map[string][]string{
1695                                 "Cookie1": {"OldValue1a", "OldValue1b"},
1696                                 "Cookie3": {"NewValue3"},
1697                                 "Cookie4": {"NewValue4"},
1698                                 "Cycle":   {"2"},
1699                         }
1700                         SetCookie(w, &Cookie{Name: "Cycle", Value: "3", Path: "/"})
1701                         SetCookie(w, &Cookie{Name: "Cookie5", Value: "NewValue5", Path: "/"}) // Insert cookie into Jar
1702                         Redirect(w, r, "/", StatusFound)
1703                 case "3":
1704                         want = map[string][]string{
1705                                 "Cookie1": {"OldValue1a", "OldValue1b"},
1706                                 "Cookie3": {"NewValue3"},
1707                                 "Cookie4": {"NewValue4"},
1708                                 "Cookie5": {"NewValue5"},
1709                                 "Cycle":   {"3"},
1710                         }
1711                         // Don't redirect to ensure the loop ends.
1712                 default:
1713                         t.Errorf("unexpected redirect cycle")
1714                         return
1715                 }
1716
1717                 if !reflect.DeepEqual(got, want) {
1718                         t.Errorf("redirect %s, Cookie = %v, want %v", c.Value, got, want)
1719                 }
1720         }))
1721         defer ts.Close()
1722
1723         jar, _ := cookiejar.New(nil)
1724         c := ts.Client()
1725         c.Jar = jar
1726
1727         u, _ := url.Parse(ts.URL)
1728         req, _ := NewRequest("GET", ts.URL, nil)
1729         req.AddCookie(&Cookie{Name: "Cookie1", Value: "OldValue1a"})
1730         req.AddCookie(&Cookie{Name: "Cookie1", Value: "OldValue1b"})
1731         req.AddCookie(&Cookie{Name: "Cookie2", Value: "OldValue2"})
1732         req.AddCookie(&Cookie{Name: "Cookie3", Value: "OldValue3a"})
1733         req.AddCookie(&Cookie{Name: "Cookie3", Value: "OldValue3b"})
1734         jar.SetCookies(u, []*Cookie{{Name: "Cookie4", Value: "OldValue4", Path: "/"}})
1735         jar.SetCookies(u, []*Cookie{{Name: "Cycle", Value: "0", Path: "/"}})
1736         res, err := c.Do(req)
1737         if err != nil {
1738                 t.Fatal(err)
1739         }
1740         defer res.Body.Close()
1741         if res.StatusCode != 200 {
1742                 t.Fatal(res.Status)
1743         }
1744 }
1745
1746 // Part of Issue 4800
1747 func TestShouldCopyHeaderOnRedirect(t *testing.T) {
1748         tests := []struct {
1749                 header     string
1750                 initialURL string
1751                 destURL    string
1752                 want       bool
1753         }{
1754                 {"User-Agent", "http://foo.com/", "http://bar.com/", true},
1755                 {"X-Foo", "http://foo.com/", "http://bar.com/", true},
1756
1757                 // Sensitive headers:
1758                 {"cookie", "http://foo.com/", "http://bar.com/", false},
1759                 {"cookie2", "http://foo.com/", "http://bar.com/", false},
1760                 {"authorization", "http://foo.com/", "http://bar.com/", false},
1761                 {"www-authenticate", "http://foo.com/", "http://bar.com/", false},
1762
1763                 // But subdomains should work:
1764                 {"www-authenticate", "http://foo.com/", "http://foo.com/", true},
1765                 {"www-authenticate", "http://foo.com/", "http://sub.foo.com/", true},
1766                 {"www-authenticate", "http://foo.com/", "http://notfoo.com/", false},
1767                 {"www-authenticate", "http://foo.com/", "https://foo.com/", false},
1768                 {"www-authenticate", "http://foo.com:80/", "http://foo.com/", true},
1769                 {"www-authenticate", "http://foo.com:80/", "http://sub.foo.com/", true},
1770                 {"www-authenticate", "http://foo.com:443/", "https://foo.com/", true},
1771                 {"www-authenticate", "http://foo.com:443/", "https://sub.foo.com/", true},
1772                 {"www-authenticate", "http://foo.com:1234/", "http://foo.com/", false},
1773         }
1774         for i, tt := range tests {
1775                 u0, err := url.Parse(tt.initialURL)
1776                 if err != nil {
1777                         t.Errorf("%d. initial URL %q parse error: %v", i, tt.initialURL, err)
1778                         continue
1779                 }
1780                 u1, err := url.Parse(tt.destURL)
1781                 if err != nil {
1782                         t.Errorf("%d. dest URL %q parse error: %v", i, tt.destURL, err)
1783                         continue
1784                 }
1785                 got := Export_shouldCopyHeaderOnRedirect(tt.header, u0, u1)
1786                 if got != tt.want {
1787                         t.Errorf("%d. shouldCopyHeaderOnRedirect(%q, %q => %q) = %v; want %v",
1788                                 i, tt.header, tt.initialURL, tt.destURL, got, tt.want)
1789                 }
1790         }
1791 }
1792
1793 func TestClientRedirectTypes(t *testing.T) {
1794         setParallel(t)
1795         defer afterTest(t)
1796
1797         tests := [...]struct {
1798                 method       string
1799                 serverStatus int
1800                 wantMethod   string // desired subsequent client method
1801         }{
1802                 0: {method: "POST", serverStatus: 301, wantMethod: "GET"},
1803                 1: {method: "POST", serverStatus: 302, wantMethod: "GET"},
1804                 2: {method: "POST", serverStatus: 303, wantMethod: "GET"},
1805                 3: {method: "POST", serverStatus: 307, wantMethod: "POST"},
1806                 4: {method: "POST", serverStatus: 308, wantMethod: "POST"},
1807
1808                 5: {method: "HEAD", serverStatus: 301, wantMethod: "HEAD"},
1809                 6: {method: "HEAD", serverStatus: 302, wantMethod: "HEAD"},
1810                 7: {method: "HEAD", serverStatus: 303, wantMethod: "HEAD"},
1811                 8: {method: "HEAD", serverStatus: 307, wantMethod: "HEAD"},
1812                 9: {method: "HEAD", serverStatus: 308, wantMethod: "HEAD"},
1813
1814                 10: {method: "GET", serverStatus: 301, wantMethod: "GET"},
1815                 11: {method: "GET", serverStatus: 302, wantMethod: "GET"},
1816                 12: {method: "GET", serverStatus: 303, wantMethod: "GET"},
1817                 13: {method: "GET", serverStatus: 307, wantMethod: "GET"},
1818                 14: {method: "GET", serverStatus: 308, wantMethod: "GET"},
1819
1820                 15: {method: "DELETE", serverStatus: 301, wantMethod: "GET"},
1821                 16: {method: "DELETE", serverStatus: 302, wantMethod: "GET"},
1822                 17: {method: "DELETE", serverStatus: 303, wantMethod: "GET"},
1823                 18: {method: "DELETE", serverStatus: 307, wantMethod: "DELETE"},
1824                 19: {method: "DELETE", serverStatus: 308, wantMethod: "DELETE"},
1825
1826                 20: {method: "PUT", serverStatus: 301, wantMethod: "GET"},
1827                 21: {method: "PUT", serverStatus: 302, wantMethod: "GET"},
1828                 22: {method: "PUT", serverStatus: 303, wantMethod: "GET"},
1829                 23: {method: "PUT", serverStatus: 307, wantMethod: "PUT"},
1830                 24: {method: "PUT", serverStatus: 308, wantMethod: "PUT"},
1831
1832                 25: {method: "MADEUPMETHOD", serverStatus: 301, wantMethod: "GET"},
1833                 26: {method: "MADEUPMETHOD", serverStatus: 302, wantMethod: "GET"},
1834                 27: {method: "MADEUPMETHOD", serverStatus: 303, wantMethod: "GET"},
1835                 28: {method: "MADEUPMETHOD", serverStatus: 307, wantMethod: "MADEUPMETHOD"},
1836                 29: {method: "MADEUPMETHOD", serverStatus: 308, wantMethod: "MADEUPMETHOD"},
1837         }
1838
1839         handlerc := make(chan HandlerFunc, 1)
1840
1841         ts := httptest.NewServer(HandlerFunc(func(rw ResponseWriter, req *Request) {
1842                 h := <-handlerc
1843                 h(rw, req)
1844         }))
1845         defer ts.Close()
1846
1847         c := ts.Client()
1848         for i, tt := range tests {
1849                 handlerc <- func(w ResponseWriter, r *Request) {
1850                         w.Header().Set("Location", ts.URL)
1851                         w.WriteHeader(tt.serverStatus)
1852                 }
1853
1854                 req, err := NewRequest(tt.method, ts.URL, nil)
1855                 if err != nil {
1856                         t.Errorf("#%d: NewRequest: %v", i, err)
1857                         continue
1858                 }
1859
1860                 c.CheckRedirect = func(req *Request, via []*Request) error {
1861                         if got, want := req.Method, tt.wantMethod; got != want {
1862                                 return fmt.Errorf("#%d: got next method %q; want %q", i, got, want)
1863                         }
1864                         handlerc <- func(rw ResponseWriter, req *Request) {
1865                                 // TODO: Check that the body is valid when we do 307 and 308 support
1866                         }
1867                         return nil
1868                 }
1869
1870                 res, err := c.Do(req)
1871                 if err != nil {
1872                         t.Errorf("#%d: Response: %v", i, err)
1873                         continue
1874                 }
1875
1876                 res.Body.Close()
1877         }
1878 }
1879
1880 // issue18239Body is an io.ReadCloser for TestTransportBodyReadError.
1881 // Its Read returns readErr and increments *readCalls atomically.
1882 // Its Close returns nil and increments *closeCalls atomically.
1883 type issue18239Body struct {
1884         readCalls  *int32
1885         closeCalls *int32
1886         readErr    error
1887 }
1888
1889 func (b issue18239Body) Read([]byte) (int, error) {
1890         atomic.AddInt32(b.readCalls, 1)
1891         return 0, b.readErr
1892 }
1893
1894 func (b issue18239Body) Close() error {
1895         atomic.AddInt32(b.closeCalls, 1)
1896         return nil
1897 }
1898
1899 // Issue 18239: make sure the Transport doesn't retry requests with bodies
1900 // if Request.GetBody is not defined.
1901 func TestTransportBodyReadError(t *testing.T) {
1902         setParallel(t)
1903         defer afterTest(t)
1904         ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
1905                 if r.URL.Path == "/ping" {
1906                         return
1907                 }
1908                 buf := make([]byte, 1)
1909                 n, err := r.Body.Read(buf)
1910                 w.Header().Set("X-Body-Read", fmt.Sprintf("%v, %v", n, err))
1911         }))
1912         defer ts.Close()
1913         c := ts.Client()
1914         tr := c.Transport.(*Transport)
1915
1916         // Do one initial successful request to create an idle TCP connection
1917         // for the subsequent request to reuse. (The Transport only retries
1918         // requests on reused connections.)
1919         res, err := c.Get(ts.URL + "/ping")
1920         if err != nil {
1921                 t.Fatal(err)
1922         }
1923         res.Body.Close()
1924
1925         var readCallsAtomic int32
1926         var closeCallsAtomic int32 // atomic
1927         someErr := errors.New("some body read error")
1928         body := issue18239Body{&readCallsAtomic, &closeCallsAtomic, someErr}
1929
1930         req, err := NewRequest("POST", ts.URL, body)
1931         if err != nil {
1932                 t.Fatal(err)
1933         }
1934         req = req.WithT(t)
1935         _, err = tr.RoundTrip(req)
1936         if err != someErr {
1937                 t.Errorf("Got error: %v; want Request.Body read error: %v", err, someErr)
1938         }
1939
1940         // And verify that our Body wasn't used multiple times, which
1941         // would indicate retries. (as it buggily was during part of
1942         // Go 1.8's dev cycle)
1943         readCalls := atomic.LoadInt32(&readCallsAtomic)
1944         closeCalls := atomic.LoadInt32(&closeCallsAtomic)
1945         if readCalls != 1 {
1946                 t.Errorf("read calls = %d; want 1", readCalls)
1947         }
1948         if closeCalls != 1 {
1949                 t.Errorf("close calls = %d; want 1", closeCalls)
1950         }
1951 }
1952
1953 type roundTripperWithoutCloseIdle struct{}
1954
1955 func (roundTripperWithoutCloseIdle) RoundTrip(*Request) (*Response, error) { panic("unused") }
1956
1957 type roundTripperWithCloseIdle func() // underlying func is CloseIdleConnections func
1958
1959 func (roundTripperWithCloseIdle) RoundTrip(*Request) (*Response, error) { panic("unused") }
1960 func (f roundTripperWithCloseIdle) CloseIdleConnections()               { f() }
1961
1962 func TestClientCloseIdleConnections(t *testing.T) {
1963         c := &Client{Transport: roundTripperWithoutCloseIdle{}}
1964         c.CloseIdleConnections() // verify we don't crash at least
1965
1966         closed := false
1967         var tr RoundTripper = roundTripperWithCloseIdle(func() {
1968                 closed = true
1969         })
1970         c = &Client{Transport: tr}
1971         c.CloseIdleConnections()
1972         if !closed {
1973                 t.Error("not closed")
1974         }
1975 }
1976
1977 func TestClientPropagatesTimeoutToContext(t *testing.T) {
1978         errDial := errors.New("not actually dialing")
1979         c := &Client{
1980                 Timeout: 5 * time.Second,
1981                 Transport: &Transport{
1982                         DialContext: func(ctx context.Context, netw, addr string) (net.Conn, error) {
1983                                 deadline, ok := ctx.Deadline()
1984                                 if !ok {
1985                                         t.Error("no deadline")
1986                                 } else {
1987                                         t.Logf("deadline in %v", deadline.Sub(time.Now()).Round(time.Second/10))
1988                                 }
1989                                 return nil, errDial
1990                         },
1991                 },
1992         }
1993         c.Get("https://example.tld/")
1994 }
1995
1996 func TestClientDoCanceledVsTimeout_h1(t *testing.T) {
1997         testClientDoCanceledVsTimeout(t, h1Mode)
1998 }
1999
2000 func TestClientDoCanceledVsTimeout_h2(t *testing.T) {
2001         testClientDoCanceledVsTimeout(t, h2Mode)
2002 }
2003
2004 // Issue 33545: lock-in the behavior promised by Client.Do's
2005 // docs about request cancellation vs timing out.
2006 func testClientDoCanceledVsTimeout(t *testing.T, h2 bool) {
2007         defer afterTest(t)
2008         cst := newClientServerTest(t, h2, HandlerFunc(func(w ResponseWriter, r *Request) {
2009                 w.Write([]byte("Hello, World!"))
2010         }))
2011         defer cst.close()
2012
2013         cases := []string{"timeout", "canceled"}
2014
2015         for _, name := range cases {
2016                 t.Run(name, func(t *testing.T) {
2017                         var ctx context.Context
2018                         var cancel func()
2019                         if name == "timeout" {
2020                                 ctx, cancel = context.WithTimeout(context.Background(), -time.Nanosecond)
2021                         } else {
2022                                 ctx, cancel = context.WithCancel(context.Background())
2023                                 cancel()
2024                         }
2025                         defer cancel()
2026
2027                         req, _ := NewRequestWithContext(ctx, "GET", cst.ts.URL, nil)
2028                         _, err := cst.c.Do(req)
2029                         if err == nil {
2030                                 t.Fatal("Unexpectedly got a nil error")
2031                         }
2032
2033                         ue := err.(*url.Error)
2034
2035                         var wantIsTimeout bool
2036                         var wantErr error = context.Canceled
2037                         if name == "timeout" {
2038                                 wantErr = context.DeadlineExceeded
2039                                 wantIsTimeout = true
2040                         }
2041                         if g, w := ue.Timeout(), wantIsTimeout; g != w {
2042                                 t.Fatalf("url.Timeout() = %t, want %t", g, w)
2043                         }
2044                         if g, w := ue.Err, wantErr; g != w {
2045                                 t.Errorf("url.Error.Err = %v; want %v", g, w)
2046                         }
2047                 })
2048         }
2049 }
2050
2051 type nilBodyRoundTripper struct{}
2052
2053 func (nilBodyRoundTripper) RoundTrip(req *Request) (*Response, error) {
2054         return &Response{
2055                 StatusCode: StatusOK,
2056                 Status:     StatusText(StatusOK),
2057                 Body:       nil,
2058                 Request:    req,
2059         }, nil
2060 }
2061
2062 func TestClientPopulatesNilResponseBody(t *testing.T) {
2063         c := &Client{Transport: nilBodyRoundTripper{}}
2064
2065         resp, err := c.Get("http://localhost/anything")
2066         if err != nil {
2067                 t.Fatalf("Client.Get rejected Response with nil Body: %v", err)
2068         }
2069
2070         if resp.Body == nil {
2071                 t.Fatalf("Client failed to provide a non-nil Body as documented")
2072         }
2073         defer func() {
2074                 if err := resp.Body.Close(); err != nil {
2075                         t.Fatalf("error from Close on substitute Response.Body: %v", err)
2076                 }
2077         }()
2078
2079         if b, err := io.ReadAll(resp.Body); err != nil {
2080                 t.Errorf("read error from substitute Response.Body: %v", err)
2081         } else if len(b) != 0 {
2082                 t.Errorf("substitute Response.Body was unexpectedly non-empty: %q", b)
2083         }
2084 }
2085
2086 // Issue 40382: Client calls Close multiple times on Request.Body.
2087 func TestClientCallsCloseOnlyOnce(t *testing.T) {
2088         setParallel(t)
2089         defer afterTest(t)
2090         cst := newClientServerTest(t, h1Mode, HandlerFunc(func(w ResponseWriter, r *Request) {
2091                 w.WriteHeader(StatusNoContent)
2092         }))
2093         defer cst.close()
2094
2095         // Issue occurred non-deterministically: needed to occur after a successful
2096         // write (into TCP buffer) but before end of body.
2097         for i := 0; i < 50 && !t.Failed(); i++ {
2098                 body := &issue40382Body{t: t, n: 300000}
2099                 req, err := NewRequest(MethodPost, cst.ts.URL, body)
2100                 if err != nil {
2101                         t.Fatal(err)
2102                 }
2103                 resp, err := cst.tr.RoundTrip(req)
2104                 if err != nil {
2105                         t.Fatal(err)
2106                 }
2107                 resp.Body.Close()
2108         }
2109 }
2110
2111 // issue40382Body is an io.ReadCloser for TestClientCallsCloseOnlyOnce.
2112 // Its Read reads n bytes before returning io.EOF.
2113 // Its Close returns nil but fails the test if called more than once.
2114 type issue40382Body struct {
2115         t                *testing.T
2116         n                int
2117         closeCallsAtomic int32
2118 }
2119
2120 func (b *issue40382Body) Read(p []byte) (int, error) {
2121         switch {
2122         case b.n == 0:
2123                 return 0, io.EOF
2124         case b.n < len(p):
2125                 p = p[:b.n]
2126                 fallthrough
2127         default:
2128                 for i := range p {
2129                         p[i] = 'x'
2130                 }
2131                 b.n -= len(p)
2132                 return len(p), nil
2133         }
2134 }
2135
2136 func (b *issue40382Body) Close() error {
2137         if atomic.AddInt32(&b.closeCallsAtomic, 1) == 2 {
2138                 b.t.Error("Body closed more than once")
2139         }
2140         return nil
2141 }
2142
2143 func TestProbeZeroLengthBody(t *testing.T) {
2144         setParallel(t)
2145         defer afterTest(t)
2146         reqc := make(chan struct{})
2147         cst := newClientServerTest(t, false, HandlerFunc(func(w ResponseWriter, r *Request) {
2148                 close(reqc)
2149                 if _, err := io.Copy(w, r.Body); err != nil {
2150                         t.Errorf("error copying request body: %v", err)
2151                 }
2152         }))
2153         defer cst.close()
2154
2155         bodyr, bodyw := io.Pipe()
2156         var gotBody string
2157         var wg sync.WaitGroup
2158         wg.Add(1)
2159         go func() {
2160                 defer wg.Done()
2161                 req, _ := NewRequest("GET", cst.ts.URL, bodyr)
2162                 res, err := cst.c.Do(req)
2163                 b, err := io.ReadAll(res.Body)
2164                 if err != nil {
2165                         t.Error(err)
2166                 }
2167                 gotBody = string(b)
2168         }()
2169
2170         select {
2171         case <-reqc:
2172                 // Request should be sent after trying to probe the request body for 200ms.
2173         case <-time.After(60 * time.Second):
2174                 t.Errorf("request not sent after 60s")
2175         }
2176
2177         // Write the request body and wait for the request to complete.
2178         const content = "body"
2179         bodyw.Write([]byte(content))
2180         bodyw.Close()
2181         wg.Wait()
2182         if gotBody != content {
2183                 t.Fatalf("server got body %q, want %q", gotBody, content)
2184         }
2185 }