mirror of
https://github.com/golang/go
synced 2024-11-23 05:00:07 -07:00
net/http: add a Request.Cancel channel.
This allows for "race free" cancellation, in the sense discussed in issue #11013: in contrast to Transport.CancelRequest, the cancellation will not be lost if the user cancels before the request is put into the transport's internal map. Fixes #11013. Change-Id: I0b5e7181231bdd65d900e343f764b4d1d7c422cd Reviewed-on: https://go-review.googlesource.com/11601 Run-TryBot: David Symonds <dsymonds@golang.org> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
This commit is contained in:
parent
1122836b5f
commit
8b4278ffb7
@ -224,6 +224,13 @@ type Request struct {
|
||||
// otherwise it leaves the field nil.
|
||||
// This field is ignored by the HTTP client.
|
||||
TLS *tls.ConnectionState
|
||||
|
||||
// Cancel is an optional channel whose closure indicates that the client
|
||||
// request should be regarded as canceled. Not all implementations of
|
||||
// RoundTripper may support Cancel.
|
||||
//
|
||||
// For server requests, this field is not applicable.
|
||||
Cancel <-chan struct{}
|
||||
}
|
||||
|
||||
// ProtoAtLeast reports whether the HTTP protocol used
|
||||
|
@ -274,8 +274,8 @@ func (t *Transport) CloseIdleConnections() {
|
||||
}
|
||||
}
|
||||
|
||||
// CancelRequest cancels an in-flight request by closing its
|
||||
// connection.
|
||||
// CancelRequest cancels an in-flight request by closing its connection.
|
||||
// CancelRequest should only be called after RoundTrip has returned.
|
||||
func (t *Transport) CancelRequest(req *Request) {
|
||||
t.reqMu.Lock()
|
||||
cancel := t.reqCanceler[req]
|
||||
@ -563,6 +563,9 @@ func (t *Transport) getConn(req *Request, cm connectMethod) (*persistConn, error
|
||||
// when it finishes:
|
||||
handlePendingDial()
|
||||
return pc, nil
|
||||
case <-req.Cancel:
|
||||
handlePendingDial()
|
||||
return nil, errors.New("net/http: request canceled while waiting for connection")
|
||||
case <-cancelc:
|
||||
handlePendingDial()
|
||||
return nil, errors.New("net/http: request canceled while waiting for connection")
|
||||
@ -971,6 +974,8 @@ func (pc *persistConn) readLoop() {
|
||||
// response body to be fully consumed before peek on
|
||||
// the underlying bufio reader.
|
||||
select {
|
||||
case <-rc.req.Cancel:
|
||||
pc.t.CancelRequest(rc.req)
|
||||
case bodyEOF := <-waitForBodyRead:
|
||||
pc.t.setReqCanceler(rc.req, nil) // before pc might return to idle pool
|
||||
alive = alive &&
|
||||
@ -1153,6 +1158,7 @@ func (pc *persistConn) roundTrip(req *transportRequest) (resp *Response, err err
|
||||
|
||||
var re responseAndError
|
||||
var respHeaderTimer <-chan time.Time
|
||||
cancelChan := req.Request.Cancel
|
||||
WaitResponse:
|
||||
for {
|
||||
select {
|
||||
@ -1193,6 +1199,9 @@ WaitResponse:
|
||||
break WaitResponse
|
||||
case re = <-resc:
|
||||
break WaitResponse
|
||||
case <-cancelChan:
|
||||
pc.t.CancelRequest(req.Request)
|
||||
cancelChan = nil
|
||||
}
|
||||
}
|
||||
|
||||
|
@ -1466,6 +1466,93 @@ Get = Get http://something.no-network.tld/: net/http: request canceled while wai
|
||||
}
|
||||
}
|
||||
|
||||
func TestCancelRequestWithChannel(t *testing.T) {
|
||||
defer afterTest(t)
|
||||
if testing.Short() {
|
||||
t.Skip("skipping test in -short mode")
|
||||
}
|
||||
unblockc := make(chan bool)
|
||||
ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
|
||||
fmt.Fprintf(w, "Hello")
|
||||
w.(Flusher).Flush() // send headers and some body
|
||||
<-unblockc
|
||||
}))
|
||||
defer ts.Close()
|
||||
defer close(unblockc)
|
||||
|
||||
tr := &Transport{}
|
||||
defer tr.CloseIdleConnections()
|
||||
c := &Client{Transport: tr}
|
||||
|
||||
req, _ := NewRequest("GET", ts.URL, nil)
|
||||
ch := make(chan struct{})
|
||||
req.Cancel = ch
|
||||
|
||||
res, err := c.Do(req)
|
||||
if err != nil {
|
||||
t.Fatal(err)
|
||||
}
|
||||
go func() {
|
||||
time.Sleep(1 * time.Second)
|
||||
close(ch)
|
||||
}()
|
||||
t0 := time.Now()
|
||||
body, err := ioutil.ReadAll(res.Body)
|
||||
d := time.Since(t0)
|
||||
|
||||
if err != ExportErrRequestCanceled {
|
||||
t.Errorf("Body.Read error = %v; want errRequestCanceled", err)
|
||||
}
|
||||
if string(body) != "Hello" {
|
||||
t.Errorf("Body = %q; want Hello", body)
|
||||
}
|
||||
if d < 500*time.Millisecond {
|
||||
t.Errorf("expected ~1 second delay; got %v", d)
|
||||
}
|
||||
// Verify no outstanding requests after readLoop/writeLoop
|
||||
// goroutines shut down.
|
||||
for tries := 5; tries > 0; tries-- {
|
||||
n := tr.NumPendingRequestsForTesting()
|
||||
if n == 0 {
|
||||
break
|
||||
}
|
||||
time.Sleep(100 * time.Millisecond)
|
||||
if tries == 1 {
|
||||
t.Errorf("pending requests = %d; want 0", n)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func TestCancelRequestWithChannelBeforeDo(t *testing.T) {
|
||||
defer afterTest(t)
|
||||
unblockc := make(chan bool)
|
||||
ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
|
||||
<-unblockc
|
||||
}))
|
||||
defer ts.Close()
|
||||
defer close(unblockc)
|
||||
|
||||
// Don't interfere with the next test on plan9.
|
||||
// Cf. http://golang.org/issues/11476
|
||||
if runtime.GOOS == "plan9" {
|
||||
defer time.Sleep(500 * time.Millisecond)
|
||||
}
|
||||
|
||||
tr := &Transport{}
|
||||
defer tr.CloseIdleConnections()
|
||||
c := &Client{Transport: tr}
|
||||
|
||||
req, _ := NewRequest("GET", ts.URL, nil)
|
||||
ch := make(chan struct{})
|
||||
req.Cancel = ch
|
||||
close(ch)
|
||||
|
||||
_, err := c.Do(req)
|
||||
if err == nil || !strings.Contains(err.Error(), "canceled") {
|
||||
t.Errorf("Do error = %v; want cancelation", err)
|
||||
}
|
||||
}
|
||||
|
||||
// golang.org/issue/3672 -- Client can't close HTTP stream
|
||||
// Calling Close on a Response.Body used to just read until EOF.
|
||||
// Now it actually closes the TCP connection.
|
||||
|
Loading…
Reference in New Issue
Block a user