Black Lives Matter. Support the Equal Justice Initiative.

Source file src/net/http/httptest/recorder_test.go

Documentation: net/http/httptest

     1  // Copyright 2012 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  package httptest
     6  
     7  import (
     8  	"fmt"
     9  	"io"
    10  	"net/http"
    11  	"testing"
    12  )
    13  
    14  func TestRecorder(t *testing.T) {
    15  	type checkFunc func(*ResponseRecorder) error
    16  	check := func(fns ...checkFunc) []checkFunc { return fns }
    17  
    18  	hasStatus := func(wantCode int) checkFunc {
    19  		return func(rec *ResponseRecorder) error {
    20  			if rec.Code != wantCode {
    21  				return fmt.Errorf("Status = %d; want %d", rec.Code, wantCode)
    22  			}
    23  			return nil
    24  		}
    25  	}
    26  	hasResultStatus := func(want string) checkFunc {
    27  		return func(rec *ResponseRecorder) error {
    28  			if rec.Result().Status != want {
    29  				return fmt.Errorf("Result().Status = %q; want %q", rec.Result().Status, want)
    30  			}
    31  			return nil
    32  		}
    33  	}
    34  	hasResultStatusCode := func(wantCode int) checkFunc {
    35  		return func(rec *ResponseRecorder) error {
    36  			if rec.Result().StatusCode != wantCode {
    37  				return fmt.Errorf("Result().StatusCode = %d; want %d", rec.Result().StatusCode, wantCode)
    38  			}
    39  			return nil
    40  		}
    41  	}
    42  	hasResultContents := func(want string) checkFunc {
    43  		return func(rec *ResponseRecorder) error {
    44  			contentBytes, err := io.ReadAll(rec.Result().Body)
    45  			if err != nil {
    46  				return err
    47  			}
    48  			contents := string(contentBytes)
    49  			if contents != want {
    50  				return fmt.Errorf("Result().Body = %s; want %s", contents, want)
    51  			}
    52  			return nil
    53  		}
    54  	}
    55  	hasContents := func(want string) checkFunc {
    56  		return func(rec *ResponseRecorder) error {
    57  			if rec.Body.String() != want {
    58  				return fmt.Errorf("wrote = %q; want %q", rec.Body.String(), want)
    59  			}
    60  			return nil
    61  		}
    62  	}
    63  	hasFlush := func(want bool) checkFunc {
    64  		return func(rec *ResponseRecorder) error {
    65  			if rec.Flushed != want {
    66  				return fmt.Errorf("Flushed = %v; want %v", rec.Flushed, want)
    67  			}
    68  			return nil
    69  		}
    70  	}
    71  	hasOldHeader := func(key, want string) checkFunc {
    72  		return func(rec *ResponseRecorder) error {
    73  			if got := rec.HeaderMap.Get(key); got != want {
    74  				return fmt.Errorf("HeaderMap header %s = %q; want %q", key, got, want)
    75  			}
    76  			return nil
    77  		}
    78  	}
    79  	hasHeader := func(key, want string) checkFunc {
    80  		return func(rec *ResponseRecorder) error {
    81  			if got := rec.Result().Header.Get(key); got != want {
    82  				return fmt.Errorf("final header %s = %q; want %q", key, got, want)
    83  			}
    84  			return nil
    85  		}
    86  	}
    87  	hasNotHeaders := func(keys ...string) checkFunc {
    88  		return func(rec *ResponseRecorder) error {
    89  			for _, k := range keys {
    90  				v, ok := rec.Result().Header[http.CanonicalHeaderKey(k)]
    91  				if ok {
    92  					return fmt.Errorf("unexpected header %s with value %q", k, v)
    93  				}
    94  			}
    95  			return nil
    96  		}
    97  	}
    98  	hasTrailer := func(key, want string) checkFunc {
    99  		return func(rec *ResponseRecorder) error {
   100  			if got := rec.Result().Trailer.Get(key); got != want {
   101  				return fmt.Errorf("trailer %s = %q; want %q", key, got, want)
   102  			}
   103  			return nil
   104  		}
   105  	}
   106  	hasNotTrailers := func(keys ...string) checkFunc {
   107  		return func(rec *ResponseRecorder) error {
   108  			trailers := rec.Result().Trailer
   109  			for _, k := range keys {
   110  				_, ok := trailers[http.CanonicalHeaderKey(k)]
   111  				if ok {
   112  					return fmt.Errorf("unexpected trailer %s", k)
   113  				}
   114  			}
   115  			return nil
   116  		}
   117  	}
   118  	hasContentLength := func(length int64) checkFunc {
   119  		return func(rec *ResponseRecorder) error {
   120  			if got := rec.Result().ContentLength; got != length {
   121  				return fmt.Errorf("ContentLength = %d; want %d", got, length)
   122  			}
   123  			return nil
   124  		}
   125  	}
   126  
   127  	for _, tt := range [...]struct {
   128  		name   string
   129  		h      func(w http.ResponseWriter, r *http.Request)
   130  		checks []checkFunc
   131  	}{
   132  		{
   133  			"200 default",
   134  			func(w http.ResponseWriter, r *http.Request) {},
   135  			check(hasStatus(200), hasContents("")),
   136  		},
   137  		{
   138  			"first code only",
   139  			func(w http.ResponseWriter, r *http.Request) {
   140  				w.WriteHeader(201)
   141  				w.WriteHeader(202)
   142  				w.Write([]byte("hi"))
   143  			},
   144  			check(hasStatus(201), hasContents("hi")),
   145  		},
   146  		{
   147  			"write sends 200",
   148  			func(w http.ResponseWriter, r *http.Request) {
   149  				w.Write([]byte("hi first"))
   150  				w.WriteHeader(201)
   151  				w.WriteHeader(202)
   152  			},
   153  			check(hasStatus(200), hasContents("hi first"), hasFlush(false)),
   154  		},
   155  		{
   156  			"write string",
   157  			func(w http.ResponseWriter, r *http.Request) {
   158  				io.WriteString(w, "hi first")
   159  			},
   160  			check(
   161  				hasStatus(200),
   162  				hasContents("hi first"),
   163  				hasFlush(false),
   164  				hasHeader("Content-Type", "text/plain; charset=utf-8"),
   165  			),
   166  		},
   167  		{
   168  			"flush",
   169  			func(w http.ResponseWriter, r *http.Request) {
   170  				w.(http.Flusher).Flush() // also sends a 200
   171  				w.WriteHeader(201)
   172  			},
   173  			check(hasStatus(200), hasFlush(true), hasContentLength(-1)),
   174  		},
   175  		{
   176  			"Content-Type detection",
   177  			func(w http.ResponseWriter, r *http.Request) {
   178  				io.WriteString(w, "<html>")
   179  			},
   180  			check(hasHeader("Content-Type", "text/html; charset=utf-8")),
   181  		},
   182  		{
   183  			"no Content-Type detection with Transfer-Encoding",
   184  			func(w http.ResponseWriter, r *http.Request) {
   185  				w.Header().Set("Transfer-Encoding", "some encoding")
   186  				io.WriteString(w, "<html>")
   187  			},
   188  			check(hasHeader("Content-Type", "")), // no header
   189  		},
   190  		{
   191  			"no Content-Type detection if set explicitly",
   192  			func(w http.ResponseWriter, r *http.Request) {
   193  				w.Header().Set("Content-Type", "some/type")
   194  				io.WriteString(w, "<html>")
   195  			},
   196  			check(hasHeader("Content-Type", "some/type")),
   197  		},
   198  		{
   199  			"Content-Type detection doesn't crash if HeaderMap is nil",
   200  			func(w http.ResponseWriter, r *http.Request) {
   201  				// Act as if the user wrote new(httptest.ResponseRecorder)
   202  				// rather than using NewRecorder (which initializes
   203  				// HeaderMap)
   204  				w.(*ResponseRecorder).HeaderMap = nil
   205  				io.WriteString(w, "<html>")
   206  			},
   207  			check(hasHeader("Content-Type", "text/html; charset=utf-8")),
   208  		},
   209  		{
   210  			"Header is not changed after write",
   211  			func(w http.ResponseWriter, r *http.Request) {
   212  				hdr := w.Header()
   213  				hdr.Set("Key", "correct")
   214  				w.WriteHeader(200)
   215  				hdr.Set("Key", "incorrect")
   216  			},
   217  			check(hasHeader("Key", "correct")),
   218  		},
   219  		{
   220  			"Trailer headers are correctly recorded",
   221  			func(w http.ResponseWriter, r *http.Request) {
   222  				w.Header().Set("Non-Trailer", "correct")
   223  				w.Header().Set("Trailer", "Trailer-A")
   224  				w.Header().Add("Trailer", "Trailer-B")
   225  				w.Header().Add("Trailer", "Trailer-C")
   226  				io.WriteString(w, "<html>")
   227  				w.Header().Set("Non-Trailer", "incorrect")
   228  				w.Header().Set("Trailer-A", "valuea")
   229  				w.Header().Set("Trailer-C", "valuec")
   230  				w.Header().Set("Trailer-NotDeclared", "should be omitted")
   231  				w.Header().Set("Trailer:Trailer-D", "with prefix")
   232  			},
   233  			check(
   234  				hasStatus(200),
   235  				hasHeader("Content-Type", "text/html; charset=utf-8"),
   236  				hasHeader("Non-Trailer", "correct"),
   237  				hasNotHeaders("Trailer-A", "Trailer-B", "Trailer-C", "Trailer-NotDeclared"),
   238  				hasTrailer("Trailer-A", "valuea"),
   239  				hasTrailer("Trailer-C", "valuec"),
   240  				hasNotTrailers("Non-Trailer", "Trailer-B", "Trailer-NotDeclared"),
   241  				hasTrailer("Trailer-D", "with prefix"),
   242  			),
   243  		},
   244  		{
   245  			"Header set without any write", // Issue 15560
   246  			func(w http.ResponseWriter, r *http.Request) {
   247  				w.Header().Set("X-Foo", "1")
   248  
   249  				// Simulate somebody using
   250  				// new(ResponseRecorder) instead of
   251  				// using the constructor which sets
   252  				// this to 200
   253  				w.(*ResponseRecorder).Code = 0
   254  			},
   255  			check(
   256  				hasOldHeader("X-Foo", "1"),
   257  				hasStatus(0),
   258  				hasHeader("X-Foo", "1"),
   259  				hasResultStatus("200 OK"),
   260  				hasResultStatusCode(200),
   261  			),
   262  		},
   263  		{
   264  			"HeaderMap vs FinalHeaders", // more for Issue 15560
   265  			func(w http.ResponseWriter, r *http.Request) {
   266  				h := w.Header()
   267  				h.Set("X-Foo", "1")
   268  				w.Write([]byte("hi"))
   269  				h.Set("X-Foo", "2")
   270  				h.Set("X-Bar", "2")
   271  			},
   272  			check(
   273  				hasOldHeader("X-Foo", "2"),
   274  				hasOldHeader("X-Bar", "2"),
   275  				hasHeader("X-Foo", "1"),
   276  				hasNotHeaders("X-Bar"),
   277  			),
   278  		},
   279  		{
   280  			"setting Content-Length header",
   281  			func(w http.ResponseWriter, r *http.Request) {
   282  				body := "Some body"
   283  				contentLength := fmt.Sprintf("%d", len(body))
   284  				w.Header().Set("Content-Length", contentLength)
   285  				io.WriteString(w, body)
   286  			},
   287  			check(hasStatus(200), hasContents("Some body"), hasContentLength(9)),
   288  		},
   289  		{
   290  			"nil ResponseRecorder.Body", // Issue 26642
   291  			func(w http.ResponseWriter, r *http.Request) {
   292  				w.(*ResponseRecorder).Body = nil
   293  				io.WriteString(w, "hi")
   294  			},
   295  			check(hasResultContents("")), // check we don't crash reading the body
   296  
   297  		},
   298  	} {
   299  		t.Run(tt.name, func(t *testing.T) {
   300  			r, _ := http.NewRequest("GET", "http://foo.com/", nil)
   301  			h := http.HandlerFunc(tt.h)
   302  			rec := NewRecorder()
   303  			h.ServeHTTP(rec, r)
   304  			for _, check := range tt.checks {
   305  				if err := check(rec); err != nil {
   306  					t.Error(err)
   307  				}
   308  			}
   309  		})
   310  	}
   311  }
   312  
   313  // issue 39017 - disallow Content-Length values such as "+3"
   314  func TestParseContentLength(t *testing.T) {
   315  	tests := []struct {
   316  		cl   string
   317  		want int64
   318  	}{
   319  		{
   320  			cl:   "3",
   321  			want: 3,
   322  		},
   323  		{
   324  			cl:   "+3",
   325  			want: -1,
   326  		},
   327  		{
   328  			cl:   "-3",
   329  			want: -1,
   330  		},
   331  		{
   332  			// max int64, for safe conversion before returning
   333  			cl:   "9223372036854775807",
   334  			want: 9223372036854775807,
   335  		},
   336  		{
   337  			cl:   "9223372036854775808",
   338  			want: -1,
   339  		},
   340  	}
   341  
   342  	for _, tt := range tests {
   343  		if got := parseContentLength(tt.cl); got != tt.want {
   344  			t.Errorf("%q:\n\tgot=%d\n\twant=%d", tt.cl, got, tt.want)
   345  		}
   346  	}
   347  }
   348  
   349  // Ensure that httptest.Recorder panics when given a non-3 digit (XXX)
   350  // status HTTP code. See https://golang.org/issues/45353
   351  func TestRecorderPanicsOnNonXXXStatusCode(t *testing.T) {
   352  	badCodes := []int{
   353  		-100, 0, 99, 1000, 20000,
   354  	}
   355  	for _, badCode := range badCodes {
   356  		badCode := badCode
   357  		t.Run(fmt.Sprintf("Code=%d", badCode), func(t *testing.T) {
   358  			defer func() {
   359  				if r := recover(); r == nil {
   360  					t.Fatal("Expected a panic")
   361  				}
   362  			}()
   363  
   364  			handler := func(rw http.ResponseWriter, _ *http.Request) {
   365  				rw.WriteHeader(badCode)
   366  			}
   367  			r, _ := http.NewRequest("GET", "http://example.org/", nil)
   368  			rw := NewRecorder()
   369  			handler(rw, r)
   370  		})
   371  	}
   372  }
   373  

View as plain text