open-consul/vendor/golang.org/x/net/http2/transport.go
Matt Keeler 2ab8af4093
Add a test for go routine leaks
This is in its own separate package so that it will be a separate test binary that runs thus isolating the go runtime from other tests and allowing accurate go routine leak checking.

This test would ideally use goleak.VerifyTestMain but that will fail 100% of the time due to some architectural things (blocking queries and net/rpc uncancellability).

This test is not comprehensive. We should enable/exercise more features and more cluster configurations. However its a start.
2020-06-24 17:09:50 -04:00

2668 lines
74 KiB
Go

// Copyright 2015 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Transport code.
package http2
import (
"bufio"
"bytes"
"compress/gzip"
"context"
"crypto/rand"
"crypto/tls"
"errors"
"fmt"
"io"
"io/ioutil"
"log"
"math"
mathrand "math/rand"
"net"
"net/http"
"net/http/httptrace"
"net/textproto"
"sort"
"strconv"
"strings"
"sync"
"sync/atomic"
"time"
"golang.org/x/net/http/httpguts"
"golang.org/x/net/http2/hpack"
"golang.org/x/net/idna"
)
const (
// transportDefaultConnFlow is how many connection-level flow control
// tokens we give the server at start-up, past the default 64k.
transportDefaultConnFlow = 1 << 30
// transportDefaultStreamFlow is how many stream-level flow
// control tokens we announce to the peer, and how many bytes
// we buffer per stream.
transportDefaultStreamFlow = 4 << 20
// transportDefaultStreamMinRefresh is the minimum number of bytes we'll send
// a stream-level WINDOW_UPDATE for at a time.
transportDefaultStreamMinRefresh = 4 << 10
defaultUserAgent = "Go-http-client/2.0"
)
// Transport is an HTTP/2 Transport.
//
// A Transport internally caches connections to servers. It is safe
// for concurrent use by multiple goroutines.
type Transport struct {
// DialTLS specifies an optional dial function for creating
// TLS connections for requests.
//
// If DialTLS is nil, tls.Dial is used.
//
// If the returned net.Conn has a ConnectionState method like tls.Conn,
// it will be used to set http.Response.TLS.
DialTLS func(network, addr string, cfg *tls.Config) (net.Conn, error)
// TLSClientConfig specifies the TLS configuration to use with
// tls.Client. If nil, the default configuration is used.
TLSClientConfig *tls.Config
// ConnPool optionally specifies an alternate connection pool to use.
// If nil, the default is used.
ConnPool ClientConnPool
// DisableCompression, if true, prevents the Transport from
// requesting compression with an "Accept-Encoding: gzip"
// request header when the Request contains no existing
// Accept-Encoding value. If the Transport requests gzip on
// its own and gets a gzipped response, it's transparently
// decoded in the Response.Body. However, if the user
// explicitly requested gzip it is not automatically
// uncompressed.
DisableCompression bool
// AllowHTTP, if true, permits HTTP/2 requests using the insecure,
// plain-text "http" scheme. Note that this does not enable h2c support.
AllowHTTP bool
// MaxHeaderListSize is the http2 SETTINGS_MAX_HEADER_LIST_SIZE to
// send in the initial settings frame. It is how many bytes
// of response headers are allowed. Unlike the http2 spec, zero here
// means to use a default limit (currently 10MB). If you actually
// want to advertise an unlimited value to the peer, Transport
// interprets the highest possible value here (0xffffffff or 1<<32-1)
// to mean no limit.
MaxHeaderListSize uint32
// StrictMaxConcurrentStreams controls whether the server's
// SETTINGS_MAX_CONCURRENT_STREAMS should be respected
// globally. If false, new TCP connections are created to the
// server as needed to keep each under the per-connection
// SETTINGS_MAX_CONCURRENT_STREAMS limit. If true, the
// server's SETTINGS_MAX_CONCURRENT_STREAMS is interpreted as
// a global limit and callers of RoundTrip block when needed,
// waiting for their turn.
StrictMaxConcurrentStreams bool
// t1, if non-nil, is the standard library Transport using
// this transport. Its settings are used (but not its
// RoundTrip method, etc).
t1 *http.Transport
connPoolOnce sync.Once
connPoolOrDef ClientConnPool // non-nil version of ConnPool
}
func (t *Transport) maxHeaderListSize() uint32 {
if t.MaxHeaderListSize == 0 {
return 10 << 20
}
if t.MaxHeaderListSize == 0xffffffff {
return 0
}
return t.MaxHeaderListSize
}
func (t *Transport) disableCompression() bool {
return t.DisableCompression || (t.t1 != nil && t.t1.DisableCompression)
}
// ConfigureTransport configures a net/http HTTP/1 Transport to use HTTP/2.
// It returns an error if t1 has already been HTTP/2-enabled.
func ConfigureTransport(t1 *http.Transport) error {
_, err := configureTransport(t1)
return err
}
func configureTransport(t1 *http.Transport) (*Transport, error) {
connPool := new(clientConnPool)
t2 := &Transport{
ConnPool: noDialClientConnPool{connPool},
t1: t1,
}
connPool.t = t2
if err := registerHTTPSProtocol(t1, noDialH2RoundTripper{t2}); err != nil {
return nil, err
}
if t1.TLSClientConfig == nil {
t1.TLSClientConfig = new(tls.Config)
}
if !strSliceContains(t1.TLSClientConfig.NextProtos, "h2") {
t1.TLSClientConfig.NextProtos = append([]string{"h2"}, t1.TLSClientConfig.NextProtos...)
}
if !strSliceContains(t1.TLSClientConfig.NextProtos, "http/1.1") {
t1.TLSClientConfig.NextProtos = append(t1.TLSClientConfig.NextProtos, "http/1.1")
}
upgradeFn := func(authority string, c *tls.Conn) http.RoundTripper {
addr := authorityAddr("https", authority)
if used, err := connPool.addConnIfNeeded(addr, t2, c); err != nil {
go c.Close()
return erringRoundTripper{err}
} else if !used {
// Turns out we don't need this c.
// For example, two goroutines made requests to the same host
// at the same time, both kicking off TCP dials. (since protocol
// was unknown)
go c.Close()
}
return t2
}
if m := t1.TLSNextProto; len(m) == 0 {
t1.TLSNextProto = map[string]func(string, *tls.Conn) http.RoundTripper{
"h2": upgradeFn,
}
} else {
m["h2"] = upgradeFn
}
return t2, nil
}
func (t *Transport) connPool() ClientConnPool {
t.connPoolOnce.Do(t.initConnPool)
return t.connPoolOrDef
}
func (t *Transport) initConnPool() {
if t.ConnPool != nil {
t.connPoolOrDef = t.ConnPool
} else {
t.connPoolOrDef = &clientConnPool{t: t}
}
}
// ClientConn is the state of a single HTTP/2 client connection to an
// HTTP/2 server.
type ClientConn struct {
t *Transport
tconn net.Conn // usually *tls.Conn, except specialized impls
tlsState *tls.ConnectionState // nil only for specialized impls
reused uint32 // whether conn is being reused; atomic
singleUse bool // whether being used for a single http.Request
// readLoop goroutine fields:
readerDone chan struct{} // closed on error
readerErr error // set before readerDone is closed
idleTimeout time.Duration // or 0 for never
idleTimer *time.Timer
mu sync.Mutex // guards following
cond *sync.Cond // hold mu; broadcast on flow/closed changes
flow flow // our conn-level flow control quota (cs.flow is per stream)
inflow flow // peer's conn-level flow control
closing bool
closed bool
wantSettingsAck bool // we sent a SETTINGS frame and haven't heard back
goAway *GoAwayFrame // if non-nil, the GoAwayFrame we received
goAwayDebug string // goAway frame's debug data, retained as a string
streams map[uint32]*clientStream // client-initiated
nextStreamID uint32
pendingRequests int // requests blocked and waiting to be sent because len(streams) == maxConcurrentStreams
pings map[[8]byte]chan struct{} // in flight ping data to notification channel
bw *bufio.Writer
br *bufio.Reader
fr *Framer
lastActive time.Time
lastIdle time.Time // time last idle
// Settings from peer: (also guarded by mu)
maxFrameSize uint32
maxConcurrentStreams uint32
peerMaxHeaderListSize uint64
initialWindowSize uint32
hbuf bytes.Buffer // HPACK encoder writes into this
henc *hpack.Encoder
freeBuf [][]byte
wmu sync.Mutex // held while writing; acquire AFTER mu if holding both
werr error // first write error that has occurred
}
// clientStream is the state for a single HTTP/2 stream. One of these
// is created for each Transport.RoundTrip call.
type clientStream struct {
cc *ClientConn
req *http.Request
trace *httptrace.ClientTrace // or nil
ID uint32
resc chan resAndError
bufPipe pipe // buffered pipe with the flow-controlled response payload
startedWrite bool // started request body write; guarded by cc.mu
requestedGzip bool
on100 func() // optional code to run if get a 100 continue response
flow flow // guarded by cc.mu
inflow flow // guarded by cc.mu
bytesRemain int64 // -1 means unknown; owned by transportResponseBody.Read
readErr error // sticky read error; owned by transportResponseBody.Read
stopReqBody error // if non-nil, stop writing req body; guarded by cc.mu
didReset bool // whether we sent a RST_STREAM to the server; guarded by cc.mu
peerReset chan struct{} // closed on peer reset
resetErr error // populated before peerReset is closed
done chan struct{} // closed when stream remove from cc.streams map; close calls guarded by cc.mu
// owned by clientConnReadLoop:
firstByte bool // got the first response byte
pastHeaders bool // got first MetaHeadersFrame (actual headers)
pastTrailers bool // got optional second MetaHeadersFrame (trailers)
num1xx uint8 // number of 1xx responses seen
trailer http.Header // accumulated trailers
resTrailer *http.Header // client's Response.Trailer
}
// awaitRequestCancel waits for the user to cancel a request or for the done
// channel to be signaled. A non-nil error is returned only if the request was
// canceled.
func awaitRequestCancel(req *http.Request, done <-chan struct{}) error {
ctx := req.Context()
if req.Cancel == nil && ctx.Done() == nil {
return nil
}
select {
case <-req.Cancel:
return errRequestCanceled
case <-ctx.Done():
return ctx.Err()
case <-done:
return nil
}
}
var got1xxFuncForTests func(int, textproto.MIMEHeader) error
// get1xxTraceFunc returns the value of request's httptrace.ClientTrace.Got1xxResponse func,
// if any. It returns nil if not set or if the Go version is too old.
func (cs *clientStream) get1xxTraceFunc() func(int, textproto.MIMEHeader) error {
if fn := got1xxFuncForTests; fn != nil {
return fn
}
return traceGot1xxResponseFunc(cs.trace)
}
// awaitRequestCancel waits for the user to cancel a request, its context to
// expire, or for the request to be done (any way it might be removed from the
// cc.streams map: peer reset, successful completion, TCP connection breakage,
// etc). If the request is canceled, then cs will be canceled and closed.
func (cs *clientStream) awaitRequestCancel(req *http.Request) {
if err := awaitRequestCancel(req, cs.done); err != nil {
cs.cancelStream()
cs.bufPipe.CloseWithError(err)
}
}
func (cs *clientStream) cancelStream() {
cc := cs.cc
cc.mu.Lock()
didReset := cs.didReset
cs.didReset = true
cc.mu.Unlock()
if !didReset {
cc.writeStreamReset(cs.ID, ErrCodeCancel, nil)
cc.forgetStreamID(cs.ID)
}
}
// checkResetOrDone reports any error sent in a RST_STREAM frame by the
// server, or errStreamClosed if the stream is complete.
func (cs *clientStream) checkResetOrDone() error {
select {
case <-cs.peerReset:
return cs.resetErr
case <-cs.done:
return errStreamClosed
default:
return nil
}
}
func (cs *clientStream) getStartedWrite() bool {
cc := cs.cc
cc.mu.Lock()
defer cc.mu.Unlock()
return cs.startedWrite
}
func (cs *clientStream) abortRequestBodyWrite(err error) {
if err == nil {
panic("nil error")
}
cc := cs.cc
cc.mu.Lock()
cs.stopReqBody = err
cc.cond.Broadcast()
cc.mu.Unlock()
}
type stickyErrWriter struct {
w io.Writer
err *error
}
func (sew stickyErrWriter) Write(p []byte) (n int, err error) {
if *sew.err != nil {
return 0, *sew.err
}
n, err = sew.w.Write(p)
*sew.err = err
return
}
// noCachedConnError is the concrete type of ErrNoCachedConn, which
// needs to be detected by net/http regardless of whether it's its
// bundled version (in h2_bundle.go with a rewritten type name) or
// from a user's x/net/http2. As such, as it has a unique method name
// (IsHTTP2NoCachedConnError) that net/http sniffs for via func
// isNoCachedConnError.
type noCachedConnError struct{}
func (noCachedConnError) IsHTTP2NoCachedConnError() {}
func (noCachedConnError) Error() string { return "http2: no cached connection was available" }
// isNoCachedConnError reports whether err is of type noCachedConnError
// or its equivalent renamed type in net/http2's h2_bundle.go. Both types
// may coexist in the same running program.
func isNoCachedConnError(err error) bool {
_, ok := err.(interface{ IsHTTP2NoCachedConnError() })
return ok
}
var ErrNoCachedConn error = noCachedConnError{}
// RoundTripOpt are options for the Transport.RoundTripOpt method.
type RoundTripOpt struct {
// OnlyCachedConn controls whether RoundTripOpt may
// create a new TCP connection. If set true and
// no cached connection is available, RoundTripOpt
// will return ErrNoCachedConn.
OnlyCachedConn bool
}
func (t *Transport) RoundTrip(req *http.Request) (*http.Response, error) {
return t.RoundTripOpt(req, RoundTripOpt{})
}
// authorityAddr returns a given authority (a host/IP, or host:port / ip:port)
// and returns a host:port. The port 443 is added if needed.
func authorityAddr(scheme string, authority string) (addr string) {
host, port, err := net.SplitHostPort(authority)
if err != nil { // authority didn't have a port
port = "443"
if scheme == "http" {
port = "80"
}
host = authority
}
if a, err := idna.ToASCII(host); err == nil {
host = a
}
// IPv6 address literal, without a port:
if strings.HasPrefix(host, "[") && strings.HasSuffix(host, "]") {
return host + ":" + port
}
return net.JoinHostPort(host, port)
}
// RoundTripOpt is like RoundTrip, but takes options.
func (t *Transport) RoundTripOpt(req *http.Request, opt RoundTripOpt) (*http.Response, error) {
if !(req.URL.Scheme == "https" || (req.URL.Scheme == "http" && t.AllowHTTP)) {
return nil, errors.New("http2: unsupported scheme")
}
addr := authorityAddr(req.URL.Scheme, req.URL.Host)
for retry := 0; ; retry++ {
cc, err := t.connPool().GetClientConn(req, addr)
if err != nil {
t.vlogf("http2: Transport failed to get client conn for %s: %v", addr, err)
return nil, err
}
reused := !atomic.CompareAndSwapUint32(&cc.reused, 0, 1)
traceGotConn(req, cc, reused)
res, gotErrAfterReqBodyWrite, err := cc.roundTrip(req)
if err != nil && retry <= 6 {
if req, err = shouldRetryRequest(req, err, gotErrAfterReqBodyWrite); err == nil {
// After the first retry, do exponential backoff with 10% jitter.
if retry == 0 {
continue
}
backoff := float64(uint(1) << (uint(retry) - 1))
backoff += backoff * (0.1 * mathrand.Float64())
select {
case <-time.After(time.Second * time.Duration(backoff)):
continue
case <-req.Context().Done():
return nil, req.Context().Err()
}
}
}
if err != nil {
t.vlogf("RoundTrip failure: %v", err)
return nil, err
}
return res, nil
}
}
// CloseIdleConnections closes any connections which were previously
// connected from previous requests but are now sitting idle.
// It does not interrupt any connections currently in use.
func (t *Transport) CloseIdleConnections() {
if cp, ok := t.connPool().(clientConnPoolIdleCloser); ok {
cp.closeIdleConnections()
}
}
var (
errClientConnClosed = errors.New("http2: client conn is closed")
errClientConnUnusable = errors.New("http2: client conn not usable")
errClientConnGotGoAway = errors.New("http2: Transport received Server's graceful shutdown GOAWAY")
)
// shouldRetryRequest is called by RoundTrip when a request fails to get
// response headers. It is always called with a non-nil error.
// It returns either a request to retry (either the same request, or a
// modified clone), or an error if the request can't be replayed.
func shouldRetryRequest(req *http.Request, err error, afterBodyWrite bool) (*http.Request, error) {
if !canRetryError(err) {
return nil, err
}
// If the Body is nil (or http.NoBody), it's safe to reuse
// this request and its Body.
if req.Body == nil || req.Body == http.NoBody {
return req, nil
}
// If the request body can be reset back to its original
// state via the optional req.GetBody, do that.
if req.GetBody != nil {
// TODO: consider a req.Body.Close here? or audit that all caller paths do?
body, err := req.GetBody()
if err != nil {
return nil, err
}
newReq := *req
newReq.Body = body
return &newReq, nil
}
// The Request.Body can't reset back to the beginning, but we
// don't seem to have started to read from it yet, so reuse
// the request directly. The "afterBodyWrite" means the
// bodyWrite process has started, which becomes true before
// the first Read.
if !afterBodyWrite {
return req, nil
}
return nil, fmt.Errorf("http2: Transport: cannot retry err [%v] after Request.Body was written; define Request.GetBody to avoid this error", err)
}
func canRetryError(err error) bool {
if err == errClientConnUnusable || err == errClientConnGotGoAway {
return true
}
if se, ok := err.(StreamError); ok {
return se.Code == ErrCodeRefusedStream
}
return false
}
func (t *Transport) dialClientConn(addr string, singleUse bool) (*ClientConn, error) {
host, _, err := net.SplitHostPort(addr)
if err != nil {
return nil, err
}
tconn, err := t.dialTLS()("tcp", addr, t.newTLSConfig(host))
if err != nil {
return nil, err
}
return t.newClientConn(tconn, singleUse)
}
func (t *Transport) newTLSConfig(host string) *tls.Config {
cfg := new(tls.Config)
if t.TLSClientConfig != nil {
*cfg = *t.TLSClientConfig.Clone()
}
if !strSliceContains(cfg.NextProtos, NextProtoTLS) {
cfg.NextProtos = append([]string{NextProtoTLS}, cfg.NextProtos...)
}
if cfg.ServerName == "" {
cfg.ServerName = host
}
return cfg
}
func (t *Transport) dialTLS() func(string, string, *tls.Config) (net.Conn, error) {
if t.DialTLS != nil {
return t.DialTLS
}
return t.dialTLSDefault
}
func (t *Transport) dialTLSDefault(network, addr string, cfg *tls.Config) (net.Conn, error) {
cn, err := tls.Dial(network, addr, cfg)
if err != nil {
return nil, err
}
if err := cn.Handshake(); err != nil {
return nil, err
}
if !cfg.InsecureSkipVerify {
if err := cn.VerifyHostname(cfg.ServerName); err != nil {
return nil, err
}
}
state := cn.ConnectionState()
if p := state.NegotiatedProtocol; p != NextProtoTLS {
return nil, fmt.Errorf("http2: unexpected ALPN protocol %q; want %q", p, NextProtoTLS)
}
if !state.NegotiatedProtocolIsMutual {
return nil, errors.New("http2: could not negotiate protocol mutually")
}
return cn, nil
}
// disableKeepAlives reports whether connections should be closed as
// soon as possible after handling the first request.
func (t *Transport) disableKeepAlives() bool {
return t.t1 != nil && t.t1.DisableKeepAlives
}
func (t *Transport) expectContinueTimeout() time.Duration {
if t.t1 == nil {
return 0
}
return t.t1.ExpectContinueTimeout
}
func (t *Transport) NewClientConn(c net.Conn) (*ClientConn, error) {
return t.newClientConn(c, t.disableKeepAlives())
}
func (t *Transport) newClientConn(c net.Conn, singleUse bool) (*ClientConn, error) {
cc := &ClientConn{
t: t,
tconn: c,
readerDone: make(chan struct{}),
nextStreamID: 1,
maxFrameSize: 16 << 10, // spec default
initialWindowSize: 65535, // spec default
maxConcurrentStreams: 1000, // "infinite", per spec. 1000 seems good enough.
peerMaxHeaderListSize: 0xffffffffffffffff, // "infinite", per spec. Use 2^64-1 instead.
streams: make(map[uint32]*clientStream),
singleUse: singleUse,
wantSettingsAck: true,
pings: make(map[[8]byte]chan struct{}),
}
if d := t.idleConnTimeout(); d != 0 {
cc.idleTimeout = d
cc.idleTimer = time.AfterFunc(d, cc.onIdleTimeout)
}
if VerboseLogs {
t.vlogf("http2: Transport creating client conn %p to %v", cc, c.RemoteAddr())
}
cc.cond = sync.NewCond(&cc.mu)
cc.flow.add(int32(initialWindowSize))
// TODO: adjust this writer size to account for frame size +
// MTU + crypto/tls record padding.
cc.bw = bufio.NewWriter(stickyErrWriter{c, &cc.werr})
cc.br = bufio.NewReader(c)
cc.fr = NewFramer(cc.bw, cc.br)
cc.fr.ReadMetaHeaders = hpack.NewDecoder(initialHeaderTableSize, nil)
cc.fr.MaxHeaderListSize = t.maxHeaderListSize()
// TODO: SetMaxDynamicTableSize, SetMaxDynamicTableSizeLimit on
// henc in response to SETTINGS frames?
cc.henc = hpack.NewEncoder(&cc.hbuf)
if t.AllowHTTP {
cc.nextStreamID = 3
}
if cs, ok := c.(connectionStater); ok {
state := cs.ConnectionState()
cc.tlsState = &state
}
initialSettings := []Setting{
{ID: SettingEnablePush, Val: 0},
{ID: SettingInitialWindowSize, Val: transportDefaultStreamFlow},
}
if max := t.maxHeaderListSize(); max != 0 {
initialSettings = append(initialSettings, Setting{ID: SettingMaxHeaderListSize, Val: max})
}
cc.bw.Write(clientPreface)
cc.fr.WriteSettings(initialSettings...)
cc.fr.WriteWindowUpdate(0, transportDefaultConnFlow)
cc.inflow.add(transportDefaultConnFlow + initialWindowSize)
cc.bw.Flush()
if cc.werr != nil {
return nil, cc.werr
}
go cc.readLoop()
return cc, nil
}
func (cc *ClientConn) setGoAway(f *GoAwayFrame) {
cc.mu.Lock()
defer cc.mu.Unlock()
old := cc.goAway
cc.goAway = f
// Merge the previous and current GoAway error frames.
if cc.goAwayDebug == "" {
cc.goAwayDebug = string(f.DebugData())
}
if old != nil && old.ErrCode != ErrCodeNo {
cc.goAway.ErrCode = old.ErrCode
}
last := f.LastStreamID
for streamID, cs := range cc.streams {
if streamID > last {
select {
case cs.resc <- resAndError{err: errClientConnGotGoAway}:
default:
}
}
}
}
// CanTakeNewRequest reports whether the connection can take a new request,
// meaning it has not been closed or received or sent a GOAWAY.
func (cc *ClientConn) CanTakeNewRequest() bool {
cc.mu.Lock()
defer cc.mu.Unlock()
return cc.canTakeNewRequestLocked()
}
// clientConnIdleState describes the suitability of a client
// connection to initiate a new RoundTrip request.
type clientConnIdleState struct {
canTakeNewRequest bool
freshConn bool // whether it's unused by any previous request
}
func (cc *ClientConn) idleState() clientConnIdleState {
cc.mu.Lock()
defer cc.mu.Unlock()
return cc.idleStateLocked()
}
func (cc *ClientConn) idleStateLocked() (st clientConnIdleState) {
if cc.singleUse && cc.nextStreamID > 1 {
return
}
var maxConcurrentOkay bool
if cc.t.StrictMaxConcurrentStreams {
// We'll tell the caller we can take a new request to
// prevent the caller from dialing a new TCP
// connection, but then we'll block later before
// writing it.
maxConcurrentOkay = true
} else {
maxConcurrentOkay = int64(len(cc.streams)+1) < int64(cc.maxConcurrentStreams)
}
st.canTakeNewRequest = cc.goAway == nil && !cc.closed && !cc.closing && maxConcurrentOkay &&
int64(cc.nextStreamID)+2*int64(cc.pendingRequests) < math.MaxInt32 &&
!cc.tooIdleLocked()
st.freshConn = cc.nextStreamID == 1 && st.canTakeNewRequest
return
}
func (cc *ClientConn) canTakeNewRequestLocked() bool {
st := cc.idleStateLocked()
return st.canTakeNewRequest
}
// tooIdleLocked reports whether this connection has been been sitting idle
// for too much wall time.
func (cc *ClientConn) tooIdleLocked() bool {
// The Round(0) strips the monontonic clock reading so the
// times are compared based on their wall time. We don't want
// to reuse a connection that's been sitting idle during
// VM/laptop suspend if monotonic time was also frozen.
return cc.idleTimeout != 0 && !cc.lastIdle.IsZero() && time.Since(cc.lastIdle.Round(0)) > cc.idleTimeout
}
// onIdleTimeout is called from a time.AfterFunc goroutine. It will
// only be called when we're idle, but because we're coming from a new
// goroutine, there could be a new request coming in at the same time,
// so this simply calls the synchronized closeIfIdle to shut down this
// connection. The timer could just call closeIfIdle, but this is more
// clear.
func (cc *ClientConn) onIdleTimeout() {
cc.closeIfIdle()
}
func (cc *ClientConn) closeIfIdle() {
cc.mu.Lock()
if len(cc.streams) > 0 {
cc.mu.Unlock()
return
}
cc.closed = true
nextID := cc.nextStreamID
// TODO: do clients send GOAWAY too? maybe? Just Close:
cc.mu.Unlock()
if VerboseLogs {
cc.vlogf("http2: Transport closing idle conn %p (forSingleUse=%v, maxStream=%v)", cc, cc.singleUse, nextID-2)
}
cc.tconn.Close()
}
var shutdownEnterWaitStateHook = func() {}
// Shutdown gracefully close the client connection, waiting for running streams to complete.
func (cc *ClientConn) Shutdown(ctx context.Context) error {
if err := cc.sendGoAway(); err != nil {
return err
}
// Wait for all in-flight streams to complete or connection to close
done := make(chan error, 1)
cancelled := false // guarded by cc.mu
go func() {
cc.mu.Lock()
defer cc.mu.Unlock()
for {
if len(cc.streams) == 0 || cc.closed {
cc.closed = true
done <- cc.tconn.Close()
break
}
if cancelled {
break
}
cc.cond.Wait()
}
}()
shutdownEnterWaitStateHook()
select {
case err := <-done:
return err
case <-ctx.Done():
cc.mu.Lock()
// Free the goroutine above
cancelled = true
cc.cond.Broadcast()
cc.mu.Unlock()
return ctx.Err()
}
}
func (cc *ClientConn) sendGoAway() error {
cc.mu.Lock()
defer cc.mu.Unlock()
cc.wmu.Lock()
defer cc.wmu.Unlock()
if cc.closing {
// GOAWAY sent already
return nil
}
// Send a graceful shutdown frame to server
maxStreamID := cc.nextStreamID
if err := cc.fr.WriteGoAway(maxStreamID, ErrCodeNo, nil); err != nil {
return err
}
if err := cc.bw.Flush(); err != nil {
return err
}
// Prevent new requests
cc.closing = true
return nil
}
// Close closes the client connection immediately.
//
// In-flight requests are interrupted. For a graceful shutdown, use Shutdown instead.
func (cc *ClientConn) Close() error {
cc.mu.Lock()
defer cc.cond.Broadcast()
defer cc.mu.Unlock()
err := errors.New("http2: client connection force closed via ClientConn.Close")
for id, cs := range cc.streams {
select {
case cs.resc <- resAndError{err: err}:
default:
}
cs.bufPipe.CloseWithError(err)
delete(cc.streams, id)
}
cc.closed = true
return cc.tconn.Close()
}
const maxAllocFrameSize = 512 << 10
// frameBuffer returns a scratch buffer suitable for writing DATA frames.
// They're capped at the min of the peer's max frame size or 512KB
// (kinda arbitrarily), but definitely capped so we don't allocate 4GB
// bufers.
func (cc *ClientConn) frameScratchBuffer() []byte {
cc.mu.Lock()
size := cc.maxFrameSize
if size > maxAllocFrameSize {
size = maxAllocFrameSize
}
for i, buf := range cc.freeBuf {
if len(buf) >= int(size) {
cc.freeBuf[i] = nil
cc.mu.Unlock()
return buf[:size]
}
}
cc.mu.Unlock()
return make([]byte, size)
}
func (cc *ClientConn) putFrameScratchBuffer(buf []byte) {
cc.mu.Lock()
defer cc.mu.Unlock()
const maxBufs = 4 // arbitrary; 4 concurrent requests per conn? investigate.
if len(cc.freeBuf) < maxBufs {
cc.freeBuf = append(cc.freeBuf, buf)
return
}
for i, old := range cc.freeBuf {
if old == nil {
cc.freeBuf[i] = buf
return
}
}
// forget about it.
}
// errRequestCanceled is a copy of net/http's errRequestCanceled because it's not
// exported. At least they'll be DeepEqual for h1-vs-h2 comparisons tests.
var errRequestCanceled = errors.New("net/http: request canceled")
func commaSeparatedTrailers(req *http.Request) (string, error) {
keys := make([]string, 0, len(req.Trailer))
for k := range req.Trailer {
k = http.CanonicalHeaderKey(k)
switch k {
case "Transfer-Encoding", "Trailer", "Content-Length":
return "", &badStringError{"invalid Trailer key", k}
}
keys = append(keys, k)
}
if len(keys) > 0 {
sort.Strings(keys)
return strings.Join(keys, ","), nil
}
return "", nil
}
func (cc *ClientConn) responseHeaderTimeout() time.Duration {
if cc.t.t1 != nil {
return cc.t.t1.ResponseHeaderTimeout
}
// No way to do this (yet?) with just an http2.Transport. Probably
// no need. Request.Cancel this is the new way. We only need to support
// this for compatibility with the old http.Transport fields when
// we're doing transparent http2.
return 0
}
// checkConnHeaders checks whether req has any invalid connection-level headers.
// per RFC 7540 section 8.1.2.2: Connection-Specific Header Fields.
// Certain headers are special-cased as okay but not transmitted later.
func checkConnHeaders(req *http.Request) error {
if v := req.Header.Get("Upgrade"); v != "" {
return fmt.Errorf("http2: invalid Upgrade request header: %q", req.Header["Upgrade"])
}
if vv := req.Header["Transfer-Encoding"]; len(vv) > 0 && (len(vv) > 1 || vv[0] != "" && vv[0] != "chunked") {
return fmt.Errorf("http2: invalid Transfer-Encoding request header: %q", vv)
}
if vv := req.Header["Connection"]; len(vv) > 0 && (len(vv) > 1 || vv[0] != "" && !strings.EqualFold(vv[0], "close") && !strings.EqualFold(vv[0], "keep-alive")) {
return fmt.Errorf("http2: invalid Connection request header: %q", vv)
}
return nil
}
// actualContentLength returns a sanitized version of
// req.ContentLength, where 0 actually means zero (not unknown) and -1
// means unknown.
func actualContentLength(req *http.Request) int64 {
if req.Body == nil || req.Body == http.NoBody {
return 0
}
if req.ContentLength != 0 {
return req.ContentLength
}
return -1
}
func (cc *ClientConn) RoundTrip(req *http.Request) (*http.Response, error) {
resp, _, err := cc.roundTrip(req)
return resp, err
}
func (cc *ClientConn) roundTrip(req *http.Request) (res *http.Response, gotErrAfterReqBodyWrite bool, err error) {
if err := checkConnHeaders(req); err != nil {
return nil, false, err
}
if cc.idleTimer != nil {
cc.idleTimer.Stop()
}
trailers, err := commaSeparatedTrailers(req)
if err != nil {
return nil, false, err
}
hasTrailers := trailers != ""
cc.mu.Lock()
if err := cc.awaitOpenSlotForRequest(req); err != nil {
cc.mu.Unlock()
return nil, false, err
}
body := req.Body
contentLen := actualContentLength(req)
hasBody := contentLen != 0
// TODO(bradfitz): this is a copy of the logic in net/http. Unify somewhere?
var requestedGzip bool
if !cc.t.disableCompression() &&
req.Header.Get("Accept-Encoding") == "" &&
req.Header.Get("Range") == "" &&
req.Method != "HEAD" {
// Request gzip only, not deflate. Deflate is ambiguous and
// not as universally supported anyway.
// See: https://zlib.net/zlib_faq.html#faq39
//
// Note that we don't request this for HEAD requests,
// due to a bug in nginx:
// http://trac.nginx.org/nginx/ticket/358
// https://golang.org/issue/5522
//
// We don't request gzip if the request is for a range, since
// auto-decoding a portion of a gzipped document will just fail
// anyway. See https://golang.org/issue/8923
requestedGzip = true
}
// we send: HEADERS{1}, CONTINUATION{0,} + DATA{0,} (DATA is
// sent by writeRequestBody below, along with any Trailers,
// again in form HEADERS{1}, CONTINUATION{0,})
hdrs, err := cc.encodeHeaders(req, requestedGzip, trailers, contentLen)
if err != nil {
cc.mu.Unlock()
return nil, false, err
}
cs := cc.newStream()
cs.req = req
cs.trace = httptrace.ContextClientTrace(req.Context())
cs.requestedGzip = requestedGzip
bodyWriter := cc.t.getBodyWriterState(cs, body)
cs.on100 = bodyWriter.on100
cc.wmu.Lock()
endStream := !hasBody && !hasTrailers
werr := cc.writeHeaders(cs.ID, endStream, int(cc.maxFrameSize), hdrs)
cc.wmu.Unlock()
traceWroteHeaders(cs.trace)
cc.mu.Unlock()
if werr != nil {
if hasBody {
req.Body.Close() // per RoundTripper contract
bodyWriter.cancel()
}
cc.forgetStreamID(cs.ID)
// Don't bother sending a RST_STREAM (our write already failed;
// no need to keep writing)
traceWroteRequest(cs.trace, werr)
return nil, false, werr
}
var respHeaderTimer <-chan time.Time
if hasBody {
bodyWriter.scheduleBodyWrite()
} else {
traceWroteRequest(cs.trace, nil)
if d := cc.responseHeaderTimeout(); d != 0 {
timer := time.NewTimer(d)
defer timer.Stop()
respHeaderTimer = timer.C
}
}
readLoopResCh := cs.resc
bodyWritten := false
ctx := req.Context()
handleReadLoopResponse := func(re resAndError) (*http.Response, bool, error) {
res := re.res
if re.err != nil || res.StatusCode > 299 {
// On error or status code 3xx, 4xx, 5xx, etc abort any
// ongoing write, assuming that the server doesn't care
// about our request body. If the server replied with 1xx or
// 2xx, however, then assume the server DOES potentially
// want our body (e.g. full-duplex streaming:
// golang.org/issue/13444). If it turns out the server
// doesn't, they'll RST_STREAM us soon enough. This is a
// heuristic to avoid adding knobs to Transport. Hopefully
// we can keep it.
bodyWriter.cancel()
cs.abortRequestBodyWrite(errStopReqBodyWrite)
}
if re.err != nil {
cc.forgetStreamID(cs.ID)
return nil, cs.getStartedWrite(), re.err
}
res.Request = req
res.TLS = cc.tlsState
return res, false, nil
}
for {
select {
case re := <-readLoopResCh:
return handleReadLoopResponse(re)
case <-respHeaderTimer:
if !hasBody || bodyWritten {
cc.writeStreamReset(cs.ID, ErrCodeCancel, nil)
} else {
bodyWriter.cancel()
cs.abortRequestBodyWrite(errStopReqBodyWriteAndCancel)
}
cc.forgetStreamID(cs.ID)
return nil, cs.getStartedWrite(), errTimeout
case <-ctx.Done():
if !hasBody || bodyWritten {
cc.writeStreamReset(cs.ID, ErrCodeCancel, nil)
} else {
bodyWriter.cancel()
cs.abortRequestBodyWrite(errStopReqBodyWriteAndCancel)
}
cc.forgetStreamID(cs.ID)
return nil, cs.getStartedWrite(), ctx.Err()
case <-req.Cancel:
if !hasBody || bodyWritten {
cc.writeStreamReset(cs.ID, ErrCodeCancel, nil)
} else {
bodyWriter.cancel()
cs.abortRequestBodyWrite(errStopReqBodyWriteAndCancel)
}
cc.forgetStreamID(cs.ID)
return nil, cs.getStartedWrite(), errRequestCanceled
case <-cs.peerReset:
// processResetStream already removed the
// stream from the streams map; no need for
// forgetStreamID.
return nil, cs.getStartedWrite(), cs.resetErr
case err := <-bodyWriter.resc:
// Prefer the read loop's response, if available. Issue 16102.
select {
case re := <-readLoopResCh:
return handleReadLoopResponse(re)
default:
}
if err != nil {
cc.forgetStreamID(cs.ID)
return nil, cs.getStartedWrite(), err
}
bodyWritten = true
if d := cc.responseHeaderTimeout(); d != 0 {
timer := time.NewTimer(d)
defer timer.Stop()
respHeaderTimer = timer.C
}
}
}
}
// awaitOpenSlotForRequest waits until len(streams) < maxConcurrentStreams.
// Must hold cc.mu.
func (cc *ClientConn) awaitOpenSlotForRequest(req *http.Request) error {
var waitingForConn chan struct{}
var waitingForConnErr error // guarded by cc.mu
for {
cc.lastActive = time.Now()
if cc.closed || !cc.canTakeNewRequestLocked() {
if waitingForConn != nil {
close(waitingForConn)
}
return errClientConnUnusable
}
cc.lastIdle = time.Time{}
if int64(len(cc.streams))+1 <= int64(cc.maxConcurrentStreams) {
if waitingForConn != nil {
close(waitingForConn)
}
return nil
}
// Unfortunately, we cannot wait on a condition variable and channel at
// the same time, so instead, we spin up a goroutine to check if the
// request is canceled while we wait for a slot to open in the connection.
if waitingForConn == nil {
waitingForConn = make(chan struct{})
go func() {
if err := awaitRequestCancel(req, waitingForConn); err != nil {
cc.mu.Lock()
waitingForConnErr = err
cc.cond.Broadcast()
cc.mu.Unlock()
}
}()
}
cc.pendingRequests++
cc.cond.Wait()
cc.pendingRequests--
if waitingForConnErr != nil {
return waitingForConnErr
}
}
}
// requires cc.wmu be held
func (cc *ClientConn) writeHeaders(streamID uint32, endStream bool, maxFrameSize int, hdrs []byte) error {
first := true // first frame written (HEADERS is first, then CONTINUATION)
for len(hdrs) > 0 && cc.werr == nil {
chunk := hdrs
if len(chunk) > maxFrameSize {
chunk = chunk[:maxFrameSize]
}
hdrs = hdrs[len(chunk):]
endHeaders := len(hdrs) == 0
if first {
cc.fr.WriteHeaders(HeadersFrameParam{
StreamID: streamID,
BlockFragment: chunk,
EndStream: endStream,
EndHeaders: endHeaders,
})
first = false
} else {
cc.fr.WriteContinuation(streamID, endHeaders, chunk)
}
}
// TODO(bradfitz): this Flush could potentially block (as
// could the WriteHeaders call(s) above), which means they
// wouldn't respond to Request.Cancel being readable. That's
// rare, but this should probably be in a goroutine.
cc.bw.Flush()
return cc.werr
}
// internal error values; they don't escape to callers
var (
// abort request body write; don't send cancel
errStopReqBodyWrite = errors.New("http2: aborting request body write")
// abort request body write, but send stream reset of cancel.
errStopReqBodyWriteAndCancel = errors.New("http2: canceling request")
errReqBodyTooLong = errors.New("http2: request body larger than specified content length")
)
func (cs *clientStream) writeRequestBody(body io.Reader, bodyCloser io.Closer) (err error) {
cc := cs.cc
sentEnd := false // whether we sent the final DATA frame w/ END_STREAM
buf := cc.frameScratchBuffer()
defer cc.putFrameScratchBuffer(buf)
defer func() {
traceWroteRequest(cs.trace, err)
// TODO: write h12Compare test showing whether
// Request.Body is closed by the Transport,
// and in multiple cases: server replies <=299 and >299
// while still writing request body
cerr := bodyCloser.Close()
if err == nil {
err = cerr
}
}()
req := cs.req
hasTrailers := req.Trailer != nil
remainLen := actualContentLength(req)
hasContentLen := remainLen != -1
var sawEOF bool
for !sawEOF {
n, err := body.Read(buf[:len(buf)-1])
if hasContentLen {
remainLen -= int64(n)
if remainLen == 0 && err == nil {
// The request body's Content-Length was predeclared and
// we just finished reading it all, but the underlying io.Reader
// returned the final chunk with a nil error (which is one of
// the two valid things a Reader can do at EOF). Because we'd prefer
// to send the END_STREAM bit early, double-check that we're actually
// at EOF. Subsequent reads should return (0, EOF) at this point.
// If either value is different, we return an error in one of two ways below.
var n1 int
n1, err = body.Read(buf[n:])
remainLen -= int64(n1)
}
if remainLen < 0 {
err = errReqBodyTooLong
cc.writeStreamReset(cs.ID, ErrCodeCancel, err)
return err
}
}
if err == io.EOF {
sawEOF = true
err = nil
} else if err != nil {
cc.writeStreamReset(cs.ID, ErrCodeCancel, err)
return err
}
remain := buf[:n]
for len(remain) > 0 && err == nil {
var allowed int32
allowed, err = cs.awaitFlowControl(len(remain))
switch {
case err == errStopReqBodyWrite:
return err
case err == errStopReqBodyWriteAndCancel:
cc.writeStreamReset(cs.ID, ErrCodeCancel, nil)
return err
case err != nil:
return err
}
cc.wmu.Lock()
data := remain[:allowed]
remain = remain[allowed:]
sentEnd = sawEOF && len(remain) == 0 && !hasTrailers
err = cc.fr.WriteData(cs.ID, sentEnd, data)
if err == nil {
// TODO(bradfitz): this flush is for latency, not bandwidth.
// Most requests won't need this. Make this opt-in or
// opt-out? Use some heuristic on the body type? Nagel-like
// timers? Based on 'n'? Only last chunk of this for loop,
// unless flow control tokens are low? For now, always.
// If we change this, see comment below.
err = cc.bw.Flush()
}
cc.wmu.Unlock()
}
if err != nil {
return err
}
}
if sentEnd {
// Already sent END_STREAM (which implies we have no
// trailers) and flushed, because currently all
// WriteData frames above get a flush. So we're done.
return nil
}
var trls []byte
if hasTrailers {
cc.mu.Lock()
trls, err = cc.encodeTrailers(req)
cc.mu.Unlock()
if err != nil {
cc.writeStreamReset(cs.ID, ErrCodeInternal, err)
cc.forgetStreamID(cs.ID)
return err
}
}
cc.mu.Lock()
maxFrameSize := int(cc.maxFrameSize)
cc.mu.Unlock()
cc.wmu.Lock()
defer cc.wmu.Unlock()
// Two ways to send END_STREAM: either with trailers, or
// with an empty DATA frame.
if len(trls) > 0 {
err = cc.writeHeaders(cs.ID, true, maxFrameSize, trls)
} else {
err = cc.fr.WriteData(cs.ID, true, nil)
}
if ferr := cc.bw.Flush(); ferr != nil && err == nil {
err = ferr
}
return err
}
// awaitFlowControl waits for [1, min(maxBytes, cc.cs.maxFrameSize)] flow
// control tokens from the server.
// It returns either the non-zero number of tokens taken or an error
// if the stream is dead.
func (cs *clientStream) awaitFlowControl(maxBytes int) (taken int32, err error) {
cc := cs.cc
cc.mu.Lock()
defer cc.mu.Unlock()
for {
if cc.closed {
return 0, errClientConnClosed
}
if cs.stopReqBody != nil {
return 0, cs.stopReqBody
}
if err := cs.checkResetOrDone(); err != nil {
return 0, err
}
if a := cs.flow.available(); a > 0 {
take := a
if int(take) > maxBytes {
take = int32(maxBytes) // can't truncate int; take is int32
}
if take > int32(cc.maxFrameSize) {
take = int32(cc.maxFrameSize)
}
cs.flow.take(take)
return take, nil
}
cc.cond.Wait()
}
}
type badStringError struct {
what string
str string
}
func (e *badStringError) Error() string { return fmt.Sprintf("%s %q", e.what, e.str) }
// requires cc.mu be held.
func (cc *ClientConn) encodeHeaders(req *http.Request, addGzipHeader bool, trailers string, contentLength int64) ([]byte, error) {
cc.hbuf.Reset()
host := req.Host
if host == "" {
host = req.URL.Host
}
host, err := httpguts.PunycodeHostPort(host)
if err != nil {
return nil, err
}
var path string
if req.Method != "CONNECT" {
path = req.URL.RequestURI()
if !validPseudoPath(path) {
orig := path
path = strings.TrimPrefix(path, req.URL.Scheme+"://"+host)
if !validPseudoPath(path) {
if req.URL.Opaque != "" {
return nil, fmt.Errorf("invalid request :path %q from URL.Opaque = %q", orig, req.URL.Opaque)
} else {
return nil, fmt.Errorf("invalid request :path %q", orig)
}
}
}
}
// Check for any invalid headers and return an error before we
// potentially pollute our hpack state. (We want to be able to
// continue to reuse the hpack encoder for future requests)
for k, vv := range req.Header {
if !httpguts.ValidHeaderFieldName(k) {
return nil, fmt.Errorf("invalid HTTP header name %q", k)
}
for _, v := range vv {
if !httpguts.ValidHeaderFieldValue(v) {
return nil, fmt.Errorf("invalid HTTP header value %q for header %q", v, k)
}
}
}
enumerateHeaders := func(f func(name, value string)) {
// 8.1.2.3 Request Pseudo-Header Fields
// The :path pseudo-header field includes the path and query parts of the
// target URI (the path-absolute production and optionally a '?' character
// followed by the query production (see Sections 3.3 and 3.4 of
// [RFC3986]).
f(":authority", host)
m := req.Method
if m == "" {
m = http.MethodGet
}
f(":method", m)
if req.Method != "CONNECT" {
f(":path", path)
f(":scheme", req.URL.Scheme)
}
if trailers != "" {
f("trailer", trailers)
}
var didUA bool
for k, vv := range req.Header {
if strings.EqualFold(k, "host") || strings.EqualFold(k, "content-length") {
// Host is :authority, already sent.
// Content-Length is automatic, set below.
continue
} else if strings.EqualFold(k, "connection") || strings.EqualFold(k, "proxy-connection") ||
strings.EqualFold(k, "transfer-encoding") || strings.EqualFold(k, "upgrade") ||
strings.EqualFold(k, "keep-alive") {
// Per 8.1.2.2 Connection-Specific Header
// Fields, don't send connection-specific
// fields. We have already checked if any
// are error-worthy so just ignore the rest.
continue
} else if strings.EqualFold(k, "user-agent") {
// Match Go's http1 behavior: at most one
// User-Agent. If set to nil or empty string,
// then omit it. Otherwise if not mentioned,
// include the default (below).
didUA = true
if len(vv) < 1 {
continue
}
vv = vv[:1]
if vv[0] == "" {
continue
}
} else if strings.EqualFold(k, "cookie") {
// Per 8.1.2.5 To allow for better compression efficiency, the
// Cookie header field MAY be split into separate header fields,
// each with one or more cookie-pairs.
for _, v := range vv {
for {
p := strings.IndexByte(v, ';')
if p < 0 {
break
}
f("cookie", v[:p])
p++
// strip space after semicolon if any.
for p+1 <= len(v) && v[p] == ' ' {
p++
}
v = v[p:]
}
if len(v) > 0 {
f("cookie", v)
}
}
continue
}
for _, v := range vv {
f(k, v)
}
}
if shouldSendReqContentLength(req.Method, contentLength) {
f("content-length", strconv.FormatInt(contentLength, 10))
}
if addGzipHeader {
f("accept-encoding", "gzip")
}
if !didUA {
f("user-agent", defaultUserAgent)
}
}
// Do a first pass over the headers counting bytes to ensure
// we don't exceed cc.peerMaxHeaderListSize. This is done as a
// separate pass before encoding the headers to prevent
// modifying the hpack state.
hlSize := uint64(0)
enumerateHeaders(func(name, value string) {
hf := hpack.HeaderField{Name: name, Value: value}
hlSize += uint64(hf.Size())
})
if hlSize > cc.peerMaxHeaderListSize {
return nil, errRequestHeaderListSize
}
trace := httptrace.ContextClientTrace(req.Context())
traceHeaders := traceHasWroteHeaderField(trace)
// Header list size is ok. Write the headers.
enumerateHeaders(func(name, value string) {
name = strings.ToLower(name)
cc.writeHeader(name, value)
if traceHeaders {
traceWroteHeaderField(trace, name, value)
}
})
return cc.hbuf.Bytes(), nil
}
// shouldSendReqContentLength reports whether the http2.Transport should send
// a "content-length" request header. This logic is basically a copy of the net/http
// transferWriter.shouldSendContentLength.
// The contentLength is the corrected contentLength (so 0 means actually 0, not unknown).
// -1 means unknown.
func shouldSendReqContentLength(method string, contentLength int64) bool {
if contentLength > 0 {
return true
}
if contentLength < 0 {
return false
}
// For zero bodies, whether we send a content-length depends on the method.
// It also kinda doesn't matter for http2 either way, with END_STREAM.
switch method {
case "POST", "PUT", "PATCH":
return true
default:
return false
}
}
// requires cc.mu be held.
func (cc *ClientConn) encodeTrailers(req *http.Request) ([]byte, error) {
cc.hbuf.Reset()
hlSize := uint64(0)
for k, vv := range req.Trailer {
for _, v := range vv {
hf := hpack.HeaderField{Name: k, Value: v}
hlSize += uint64(hf.Size())
}
}
if hlSize > cc.peerMaxHeaderListSize {
return nil, errRequestHeaderListSize
}
for k, vv := range req.Trailer {
// Transfer-Encoding, etc.. have already been filtered at the
// start of RoundTrip
lowKey := strings.ToLower(k)
for _, v := range vv {
cc.writeHeader(lowKey, v)
}
}
return cc.hbuf.Bytes(), nil
}
func (cc *ClientConn) writeHeader(name, value string) {
if VerboseLogs {
log.Printf("http2: Transport encoding header %q = %q", name, value)
}
cc.henc.WriteField(hpack.HeaderField{Name: name, Value: value})
}
type resAndError struct {
res *http.Response
err error
}
// requires cc.mu be held.
func (cc *ClientConn) newStream() *clientStream {
cs := &clientStream{
cc: cc,
ID: cc.nextStreamID,
resc: make(chan resAndError, 1),
peerReset: make(chan struct{}),
done: make(chan struct{}),
}
cs.flow.add(int32(cc.initialWindowSize))
cs.flow.setConnFlow(&cc.flow)
cs.inflow.add(transportDefaultStreamFlow)
cs.inflow.setConnFlow(&cc.inflow)
cc.nextStreamID += 2
cc.streams[cs.ID] = cs
return cs
}
func (cc *ClientConn) forgetStreamID(id uint32) {
cc.streamByID(id, true)
}
func (cc *ClientConn) streamByID(id uint32, andRemove bool) *clientStream {
cc.mu.Lock()
defer cc.mu.Unlock()
cs := cc.streams[id]
if andRemove && cs != nil && !cc.closed {
cc.lastActive = time.Now()
delete(cc.streams, id)
if len(cc.streams) == 0 && cc.idleTimer != nil {
cc.idleTimer.Reset(cc.idleTimeout)
cc.lastIdle = time.Now()
}
close(cs.done)
// Wake up checkResetOrDone via clientStream.awaitFlowControl and
// wake up RoundTrip if there is a pending request.
cc.cond.Broadcast()
}
return cs
}
// clientConnReadLoop is the state owned by the clientConn's frame-reading readLoop.
type clientConnReadLoop struct {
cc *ClientConn
closeWhenIdle bool
}
// readLoop runs in its own goroutine and reads and dispatches frames.
func (cc *ClientConn) readLoop() {
rl := &clientConnReadLoop{cc: cc}
defer rl.cleanup()
cc.readerErr = rl.run()
if ce, ok := cc.readerErr.(ConnectionError); ok {
cc.wmu.Lock()
cc.fr.WriteGoAway(0, ErrCode(ce), nil)
cc.wmu.Unlock()
}
}
// GoAwayError is returned by the Transport when the server closes the
// TCP connection after sending a GOAWAY frame.
type GoAwayError struct {
LastStreamID uint32
ErrCode ErrCode
DebugData string
}
func (e GoAwayError) Error() string {
return fmt.Sprintf("http2: server sent GOAWAY and closed the connection; LastStreamID=%v, ErrCode=%v, debug=%q",
e.LastStreamID, e.ErrCode, e.DebugData)
}
func isEOFOrNetReadError(err error) bool {
if err == io.EOF {
return true
}
ne, ok := err.(*net.OpError)
return ok && ne.Op == "read"
}
func (rl *clientConnReadLoop) cleanup() {
cc := rl.cc
defer cc.tconn.Close()
defer cc.t.connPool().MarkDead(cc)
defer close(cc.readerDone)
if cc.idleTimer != nil {
cc.idleTimer.Stop()
}
// Close any response bodies if the server closes prematurely.
// TODO: also do this if we've written the headers but not
// gotten a response yet.
err := cc.readerErr
cc.mu.Lock()
if cc.goAway != nil && isEOFOrNetReadError(err) {
err = GoAwayError{
LastStreamID: cc.goAway.LastStreamID,
ErrCode: cc.goAway.ErrCode,
DebugData: cc.goAwayDebug,
}
} else if err == io.EOF {
err = io.ErrUnexpectedEOF
}
for _, cs := range cc.streams {
cs.bufPipe.CloseWithError(err) // no-op if already closed
select {
case cs.resc <- resAndError{err: err}:
default:
}
close(cs.done)
}
cc.closed = true
cc.cond.Broadcast()
cc.mu.Unlock()
}
func (rl *clientConnReadLoop) run() error {
cc := rl.cc
rl.closeWhenIdle = cc.t.disableKeepAlives() || cc.singleUse
gotReply := false // ever saw a HEADERS reply
gotSettings := false
for {
f, err := cc.fr.ReadFrame()
if err != nil {
cc.vlogf("http2: Transport readFrame error on conn %p: (%T) %v", cc, err, err)
}
if se, ok := err.(StreamError); ok {
if cs := cc.streamByID(se.StreamID, false); cs != nil {
cs.cc.writeStreamReset(cs.ID, se.Code, err)
cs.cc.forgetStreamID(cs.ID)
if se.Cause == nil {
se.Cause = cc.fr.errDetail
}
rl.endStreamError(cs, se)
}
continue
} else if err != nil {
return err
}
if VerboseLogs {
cc.vlogf("http2: Transport received %s", summarizeFrame(f))
}
if !gotSettings {
if _, ok := f.(*SettingsFrame); !ok {
cc.logf("protocol error: received %T before a SETTINGS frame", f)
return ConnectionError(ErrCodeProtocol)
}
gotSettings = true
}
maybeIdle := false // whether frame might transition us to idle
switch f := f.(type) {
case *MetaHeadersFrame:
err = rl.processHeaders(f)
maybeIdle = true
gotReply = true
case *DataFrame:
err = rl.processData(f)
maybeIdle = true
case *GoAwayFrame:
err = rl.processGoAway(f)
maybeIdle = true
case *RSTStreamFrame:
err = rl.processResetStream(f)
maybeIdle = true
case *SettingsFrame:
err = rl.processSettings(f)
case *PushPromiseFrame:
err = rl.processPushPromise(f)
case *WindowUpdateFrame:
err = rl.processWindowUpdate(f)
case *PingFrame:
err = rl.processPing(f)
default:
cc.logf("Transport: unhandled response frame type %T", f)
}
if err != nil {
if VerboseLogs {
cc.vlogf("http2: Transport conn %p received error from processing frame %v: %v", cc, summarizeFrame(f), err)
}
return err
}
if rl.closeWhenIdle && gotReply && maybeIdle {
cc.closeIfIdle()
}
}
}
func (rl *clientConnReadLoop) processHeaders(f *MetaHeadersFrame) error {
cc := rl.cc
cs := cc.streamByID(f.StreamID, false)
if cs == nil {
// We'd get here if we canceled a request while the
// server had its response still in flight. So if this
// was just something we canceled, ignore it.
return nil
}
if f.StreamEnded() {
// Issue 20521: If the stream has ended, streamByID() causes
// clientStream.done to be closed, which causes the request's bodyWriter
// to be closed with an errStreamClosed, which may be received by
// clientConn.RoundTrip before the result of processing these headers.
// Deferring stream closure allows the header processing to occur first.
// clientConn.RoundTrip may still receive the bodyWriter error first, but
// the fix for issue 16102 prioritises any response.
//
// Issue 22413: If there is no request body, we should close the
// stream before writing to cs.resc so that the stream is closed
// immediately once RoundTrip returns.
if cs.req.Body != nil {
defer cc.forgetStreamID(f.StreamID)
} else {
cc.forgetStreamID(f.StreamID)
}
}
if !cs.firstByte {
if cs.trace != nil {
// TODO(bradfitz): move first response byte earlier,
// when we first read the 9 byte header, not waiting
// until all the HEADERS+CONTINUATION frames have been
// merged. This works for now.
traceFirstResponseByte(cs.trace)
}
cs.firstByte = true
}
if !cs.pastHeaders {
cs.pastHeaders = true
} else {
return rl.processTrailers(cs, f)
}
res, err := rl.handleResponse(cs, f)
if err != nil {
if _, ok := err.(ConnectionError); ok {
return err
}
// Any other error type is a stream error.
cs.cc.writeStreamReset(f.StreamID, ErrCodeProtocol, err)
cc.forgetStreamID(cs.ID)
cs.resc <- resAndError{err: err}
return nil // return nil from process* funcs to keep conn alive
}
if res == nil {
// (nil, nil) special case. See handleResponse docs.
return nil
}
cs.resTrailer = &res.Trailer
cs.resc <- resAndError{res: res}
return nil
}
// may return error types nil, or ConnectionError. Any other error value
// is a StreamError of type ErrCodeProtocol. The returned error in that case
// is the detail.
//
// As a special case, handleResponse may return (nil, nil) to skip the
// frame (currently only used for 1xx responses).
func (rl *clientConnReadLoop) handleResponse(cs *clientStream, f *MetaHeadersFrame) (*http.Response, error) {
if f.Truncated {
return nil, errResponseHeaderListSize
}
status := f.PseudoValue("status")
if status == "" {
return nil, errors.New("malformed response from server: missing status pseudo header")
}
statusCode, err := strconv.Atoi(status)
if err != nil {
return nil, errors.New("malformed response from server: malformed non-numeric status pseudo header")
}
header := make(http.Header)
res := &http.Response{
Proto: "HTTP/2.0",
ProtoMajor: 2,
Header: header,
StatusCode: statusCode,
Status: status + " " + http.StatusText(statusCode),
}
for _, hf := range f.RegularFields() {
key := http.CanonicalHeaderKey(hf.Name)
if key == "Trailer" {
t := res.Trailer
if t == nil {
t = make(http.Header)
res.Trailer = t
}
foreachHeaderElement(hf.Value, func(v string) {
t[http.CanonicalHeaderKey(v)] = nil
})
} else {
header[key] = append(header[key], hf.Value)
}
}
if statusCode >= 100 && statusCode <= 199 {
cs.num1xx++
const max1xxResponses = 5 // arbitrary bound on number of informational responses, same as net/http
if cs.num1xx > max1xxResponses {
return nil, errors.New("http2: too many 1xx informational responses")
}
if fn := cs.get1xxTraceFunc(); fn != nil {
if err := fn(statusCode, textproto.MIMEHeader(header)); err != nil {
return nil, err
}
}
if statusCode == 100 {
traceGot100Continue(cs.trace)
if cs.on100 != nil {
cs.on100() // forces any write delay timer to fire
}
}
cs.pastHeaders = false // do it all again
return nil, nil
}
streamEnded := f.StreamEnded()
isHead := cs.req.Method == "HEAD"
if !streamEnded || isHead {
res.ContentLength = -1
if clens := res.Header["Content-Length"]; len(clens) == 1 {
if clen64, err := strconv.ParseInt(clens[0], 10, 64); err == nil {
res.ContentLength = clen64
} else {
// TODO: care? unlike http/1, it won't mess up our framing, so it's
// more safe smuggling-wise to ignore.
}
} else if len(clens) > 1 {
// TODO: care? unlike http/1, it won't mess up our framing, so it's
// more safe smuggling-wise to ignore.
}
}
if streamEnded || isHead {
res.Body = noBody
return res, nil
}
cs.bufPipe = pipe{b: &dataBuffer{expected: res.ContentLength}}
cs.bytesRemain = res.ContentLength
res.Body = transportResponseBody{cs}
go cs.awaitRequestCancel(cs.req)
if cs.requestedGzip && res.Header.Get("Content-Encoding") == "gzip" {
res.Header.Del("Content-Encoding")
res.Header.Del("Content-Length")
res.ContentLength = -1
res.Body = &gzipReader{body: res.Body}
res.Uncompressed = true
}
return res, nil
}
func (rl *clientConnReadLoop) processTrailers(cs *clientStream, f *MetaHeadersFrame) error {
if cs.pastTrailers {
// Too many HEADERS frames for this stream.
return ConnectionError(ErrCodeProtocol)
}
cs.pastTrailers = true
if !f.StreamEnded() {
// We expect that any headers for trailers also
// has END_STREAM.
return ConnectionError(ErrCodeProtocol)
}
if len(f.PseudoFields()) > 0 {
// No pseudo header fields are defined for trailers.
// TODO: ConnectionError might be overly harsh? Check.
return ConnectionError(ErrCodeProtocol)
}
trailer := make(http.Header)
for _, hf := range f.RegularFields() {
key := http.CanonicalHeaderKey(hf.Name)
trailer[key] = append(trailer[key], hf.Value)
}
cs.trailer = trailer
rl.endStream(cs)
return nil
}
// transportResponseBody is the concrete type of Transport.RoundTrip's
// Response.Body. It is an io.ReadCloser. On Read, it reads from cs.body.
// On Close it sends RST_STREAM if EOF wasn't already seen.
type transportResponseBody struct {
cs *clientStream
}
func (b transportResponseBody) Read(p []byte) (n int, err error) {
cs := b.cs
cc := cs.cc
if cs.readErr != nil {
return 0, cs.readErr
}
n, err = b.cs.bufPipe.Read(p)
if cs.bytesRemain != -1 {
if int64(n) > cs.bytesRemain {
n = int(cs.bytesRemain)
if err == nil {
err = errors.New("net/http: server replied with more than declared Content-Length; truncated")
cc.writeStreamReset(cs.ID, ErrCodeProtocol, err)
}
cs.readErr = err
return int(cs.bytesRemain), err
}
cs.bytesRemain -= int64(n)
if err == io.EOF && cs.bytesRemain > 0 {
err = io.ErrUnexpectedEOF
cs.readErr = err
return n, err
}
}
if n == 0 {
// No flow control tokens to send back.
return
}
cc.mu.Lock()
defer cc.mu.Unlock()
var connAdd, streamAdd int32
// Check the conn-level first, before the stream-level.
if v := cc.inflow.available(); v < transportDefaultConnFlow/2 {
connAdd = transportDefaultConnFlow - v
cc.inflow.add(connAdd)
}
if err == nil { // No need to refresh if the stream is over or failed.
// Consider any buffered body data (read from the conn but not
// consumed by the client) when computing flow control for this
// stream.
v := int(cs.inflow.available()) + cs.bufPipe.Len()
if v < transportDefaultStreamFlow-transportDefaultStreamMinRefresh {
streamAdd = int32(transportDefaultStreamFlow - v)
cs.inflow.add(streamAdd)
}
}
if connAdd != 0 || streamAdd != 0 {
cc.wmu.Lock()
defer cc.wmu.Unlock()
if connAdd != 0 {
cc.fr.WriteWindowUpdate(0, mustUint31(connAdd))
}
if streamAdd != 0 {
cc.fr.WriteWindowUpdate(cs.ID, mustUint31(streamAdd))
}
cc.bw.Flush()
}
return
}
var errClosedResponseBody = errors.New("http2: response body closed")
func (b transportResponseBody) Close() error {
cs := b.cs
cc := cs.cc
serverSentStreamEnd := cs.bufPipe.Err() == io.EOF
unread := cs.bufPipe.Len()
if unread > 0 || !serverSentStreamEnd {
cc.mu.Lock()
cc.wmu.Lock()
if !serverSentStreamEnd {
cc.fr.WriteRSTStream(cs.ID, ErrCodeCancel)
cs.didReset = true
}
// Return connection-level flow control.
if unread > 0 {
cc.inflow.add(int32(unread))
cc.fr.WriteWindowUpdate(0, uint32(unread))
}
cc.bw.Flush()
cc.wmu.Unlock()
cc.mu.Unlock()
}
cs.bufPipe.BreakWithError(errClosedResponseBody)
cc.forgetStreamID(cs.ID)
return nil
}
func (rl *clientConnReadLoop) processData(f *DataFrame) error {
cc := rl.cc
cs := cc.streamByID(f.StreamID, f.StreamEnded())
data := f.Data()
if cs == nil {
cc.mu.Lock()
neverSent := cc.nextStreamID
cc.mu.Unlock()
if f.StreamID >= neverSent {
// We never asked for this.
cc.logf("http2: Transport received unsolicited DATA frame; closing connection")
return ConnectionError(ErrCodeProtocol)
}
// We probably did ask for this, but canceled. Just ignore it.
// TODO: be stricter here? only silently ignore things which
// we canceled, but not things which were closed normally
// by the peer? Tough without accumulating too much state.
// But at least return their flow control:
if f.Length > 0 {
cc.mu.Lock()
cc.inflow.add(int32(f.Length))
cc.mu.Unlock()
cc.wmu.Lock()
cc.fr.WriteWindowUpdate(0, uint32(f.Length))
cc.bw.Flush()
cc.wmu.Unlock()
}
return nil
}
if !cs.firstByte {
cc.logf("protocol error: received DATA before a HEADERS frame")
rl.endStreamError(cs, StreamError{
StreamID: f.StreamID,
Code: ErrCodeProtocol,
})
return nil
}
if f.Length > 0 {
if cs.req.Method == "HEAD" && len(data) > 0 {
cc.logf("protocol error: received DATA on a HEAD request")
rl.endStreamError(cs, StreamError{
StreamID: f.StreamID,
Code: ErrCodeProtocol,
})
return nil
}
// Check connection-level flow control.
cc.mu.Lock()
if cs.inflow.available() >= int32(f.Length) {
cs.inflow.take(int32(f.Length))
} else {
cc.mu.Unlock()
return ConnectionError(ErrCodeFlowControl)
}
// Return any padded flow control now, since we won't
// refund it later on body reads.
var refund int
if pad := int(f.Length) - len(data); pad > 0 {
refund += pad
}
// Return len(data) now if the stream is already closed,
// since data will never be read.
didReset := cs.didReset
if didReset {
refund += len(data)
}
if refund > 0 {
cc.inflow.add(int32(refund))
cc.wmu.Lock()
cc.fr.WriteWindowUpdate(0, uint32(refund))
if !didReset {
cs.inflow.add(int32(refund))
cc.fr.WriteWindowUpdate(cs.ID, uint32(refund))
}
cc.bw.Flush()
cc.wmu.Unlock()
}
cc.mu.Unlock()
if len(data) > 0 && !didReset {
if _, err := cs.bufPipe.Write(data); err != nil {
rl.endStreamError(cs, err)
return err
}
}
}
if f.StreamEnded() {
rl.endStream(cs)
}
return nil
}
func (rl *clientConnReadLoop) endStream(cs *clientStream) {
// TODO: check that any declared content-length matches, like
// server.go's (*stream).endStream method.
rl.endStreamError(cs, nil)
}
func (rl *clientConnReadLoop) endStreamError(cs *clientStream, err error) {
var code func()
if err == nil {
err = io.EOF
code = cs.copyTrailers
}
if isConnectionCloseRequest(cs.req) {
rl.closeWhenIdle = true
}
cs.bufPipe.closeWithErrorAndCode(err, code)
select {
case cs.resc <- resAndError{err: err}:
default:
}
}
func (cs *clientStream) copyTrailers() {
for k, vv := range cs.trailer {
t := cs.resTrailer
if *t == nil {
*t = make(http.Header)
}
(*t)[k] = vv
}
}
func (rl *clientConnReadLoop) processGoAway(f *GoAwayFrame) error {
cc := rl.cc
cc.t.connPool().MarkDead(cc)
if f.ErrCode != 0 {
// TODO: deal with GOAWAY more. particularly the error code
cc.vlogf("transport got GOAWAY with error code = %v", f.ErrCode)
}
cc.setGoAway(f)
return nil
}
func (rl *clientConnReadLoop) processSettings(f *SettingsFrame) error {
cc := rl.cc
cc.mu.Lock()
defer cc.mu.Unlock()
if f.IsAck() {
if cc.wantSettingsAck {
cc.wantSettingsAck = false
return nil
}
return ConnectionError(ErrCodeProtocol)
}
err := f.ForeachSetting(func(s Setting) error {
switch s.ID {
case SettingMaxFrameSize:
cc.maxFrameSize = s.Val
case SettingMaxConcurrentStreams:
cc.maxConcurrentStreams = s.Val
case SettingMaxHeaderListSize:
cc.peerMaxHeaderListSize = uint64(s.Val)
case SettingInitialWindowSize:
// Values above the maximum flow-control
// window size of 2^31-1 MUST be treated as a
// connection error (Section 5.4.1) of type
// FLOW_CONTROL_ERROR.
if s.Val > math.MaxInt32 {
return ConnectionError(ErrCodeFlowControl)
}
// Adjust flow control of currently-open
// frames by the difference of the old initial
// window size and this one.
delta := int32(s.Val) - int32(cc.initialWindowSize)
for _, cs := range cc.streams {
cs.flow.add(delta)
}
cc.cond.Broadcast()
cc.initialWindowSize = s.Val
default:
// TODO(bradfitz): handle more settings? SETTINGS_HEADER_TABLE_SIZE probably.
cc.vlogf("Unhandled Setting: %v", s)
}
return nil
})
if err != nil {
return err
}
cc.wmu.Lock()
defer cc.wmu.Unlock()
cc.fr.WriteSettingsAck()
cc.bw.Flush()
return cc.werr
}
func (rl *clientConnReadLoop) processWindowUpdate(f *WindowUpdateFrame) error {
cc := rl.cc
cs := cc.streamByID(f.StreamID, false)
if f.StreamID != 0 && cs == nil {
return nil
}
cc.mu.Lock()
defer cc.mu.Unlock()
fl := &cc.flow
if cs != nil {
fl = &cs.flow
}
if !fl.add(int32(f.Increment)) {
return ConnectionError(ErrCodeFlowControl)
}
cc.cond.Broadcast()
return nil
}
func (rl *clientConnReadLoop) processResetStream(f *RSTStreamFrame) error {
cs := rl.cc.streamByID(f.StreamID, true)
if cs == nil {
// TODO: return error if server tries to RST_STEAM an idle stream
return nil
}
select {
case <-cs.peerReset:
// Already reset.
// This is the only goroutine
// which closes this, so there
// isn't a race.
default:
err := streamError(cs.ID, f.ErrCode)
cs.resetErr = err
close(cs.peerReset)
cs.bufPipe.CloseWithError(err)
cs.cc.cond.Broadcast() // wake up checkResetOrDone via clientStream.awaitFlowControl
}
return nil
}
// Ping sends a PING frame to the server and waits for the ack.
func (cc *ClientConn) Ping(ctx context.Context) error {
c := make(chan struct{})
// Generate a random payload
var p [8]byte
for {
if _, err := rand.Read(p[:]); err != nil {
return err
}
cc.mu.Lock()
// check for dup before insert
if _, found := cc.pings[p]; !found {
cc.pings[p] = c
cc.mu.Unlock()
break
}
cc.mu.Unlock()
}
cc.wmu.Lock()
if err := cc.fr.WritePing(false, p); err != nil {
cc.wmu.Unlock()
return err
}
if err := cc.bw.Flush(); err != nil {
cc.wmu.Unlock()
return err
}
cc.wmu.Unlock()
select {
case <-c:
return nil
case <-ctx.Done():
return ctx.Err()
case <-cc.readerDone:
// connection closed
return cc.readerErr
}
}
func (rl *clientConnReadLoop) processPing(f *PingFrame) error {
if f.IsAck() {
cc := rl.cc
cc.mu.Lock()
defer cc.mu.Unlock()
// If ack, notify listener if any
if c, ok := cc.pings[f.Data]; ok {
close(c)
delete(cc.pings, f.Data)
}
return nil
}
cc := rl.cc
cc.wmu.Lock()
defer cc.wmu.Unlock()
if err := cc.fr.WritePing(true, f.Data); err != nil {
return err
}
return cc.bw.Flush()
}
func (rl *clientConnReadLoop) processPushPromise(f *PushPromiseFrame) error {
// We told the peer we don't want them.
// Spec says:
// "PUSH_PROMISE MUST NOT be sent if the SETTINGS_ENABLE_PUSH
// setting of the peer endpoint is set to 0. An endpoint that
// has set this setting and has received acknowledgement MUST
// treat the receipt of a PUSH_PROMISE frame as a connection
// error (Section 5.4.1) of type PROTOCOL_ERROR."
return ConnectionError(ErrCodeProtocol)
}
func (cc *ClientConn) writeStreamReset(streamID uint32, code ErrCode, err error) {
// TODO: map err to more interesting error codes, once the
// HTTP community comes up with some. But currently for
// RST_STREAM there's no equivalent to GOAWAY frame's debug
// data, and the error codes are all pretty vague ("cancel").
cc.wmu.Lock()
cc.fr.WriteRSTStream(streamID, code)
cc.bw.Flush()
cc.wmu.Unlock()
}
var (
errResponseHeaderListSize = errors.New("http2: response header list larger than advertised limit")
errRequestHeaderListSize = errors.New("http2: request header list larger than peer's advertised limit")
)
func (cc *ClientConn) logf(format string, args ...interface{}) {
cc.t.logf(format, args...)
}
func (cc *ClientConn) vlogf(format string, args ...interface{}) {
cc.t.vlogf(format, args...)
}
func (t *Transport) vlogf(format string, args ...interface{}) {
if VerboseLogs {
t.logf(format, args...)
}
}
func (t *Transport) logf(format string, args ...interface{}) {
log.Printf(format, args...)
}
var noBody io.ReadCloser = ioutil.NopCloser(bytes.NewReader(nil))
func strSliceContains(ss []string, s string) bool {
for _, v := range ss {
if v == s {
return true
}
}
return false
}
type erringRoundTripper struct{ err error }
func (rt erringRoundTripper) RoundTrip(*http.Request) (*http.Response, error) { return nil, rt.err }
// gzipReader wraps a response body so it can lazily
// call gzip.NewReader on the first call to Read
type gzipReader struct {
body io.ReadCloser // underlying Response.Body
zr *gzip.Reader // lazily-initialized gzip reader
zerr error // sticky error
}
func (gz *gzipReader) Read(p []byte) (n int, err error) {
if gz.zerr != nil {
return 0, gz.zerr
}
if gz.zr == nil {
gz.zr, err = gzip.NewReader(gz.body)
if err != nil {
gz.zerr = err
return 0, err
}
}
return gz.zr.Read(p)
}
func (gz *gzipReader) Close() error {
return gz.body.Close()
}
type errorReader struct{ err error }
func (r errorReader) Read(p []byte) (int, error) { return 0, r.err }
// bodyWriterState encapsulates various state around the Transport's writing
// of the request body, particularly regarding doing delayed writes of the body
// when the request contains "Expect: 100-continue".
type bodyWriterState struct {
cs *clientStream
timer *time.Timer // if non-nil, we're doing a delayed write
fnonce *sync.Once // to call fn with
fn func() // the code to run in the goroutine, writing the body
resc chan error // result of fn's execution
delay time.Duration // how long we should delay a delayed write for
}
func (t *Transport) getBodyWriterState(cs *clientStream, body io.Reader) (s bodyWriterState) {
s.cs = cs
if body == nil {
return
}
resc := make(chan error, 1)
s.resc = resc
s.fn = func() {
cs.cc.mu.Lock()
cs.startedWrite = true
cs.cc.mu.Unlock()
resc <- cs.writeRequestBody(body, cs.req.Body)
}
s.delay = t.expectContinueTimeout()
if s.delay == 0 ||
!httpguts.HeaderValuesContainsToken(
cs.req.Header["Expect"],
"100-continue") {
return
}
s.fnonce = new(sync.Once)
// Arm the timer with a very large duration, which we'll
// intentionally lower later. It has to be large now because
// we need a handle to it before writing the headers, but the
// s.delay value is defined to not start until after the
// request headers were written.
const hugeDuration = 365 * 24 * time.Hour
s.timer = time.AfterFunc(hugeDuration, func() {
s.fnonce.Do(s.fn)
})
return
}
func (s bodyWriterState) cancel() {
if s.timer != nil {
s.timer.Stop()
}
}
func (s bodyWriterState) on100() {
if s.timer == nil {
// If we didn't do a delayed write, ignore the server's
// bogus 100 continue response.
return
}
s.timer.Stop()
go func() { s.fnonce.Do(s.fn) }()
}
// scheduleBodyWrite starts writing the body, either immediately (in
// the common case) or after the delay timeout. It should not be
// called until after the headers have been written.
func (s bodyWriterState) scheduleBodyWrite() {
if s.timer == nil {
// We're not doing a delayed write (see
// getBodyWriterState), so just start the writing
// goroutine immediately.
go s.fn()
return
}
traceWait100Continue(s.cs.trace)
if s.timer.Stop() {
s.timer.Reset(s.delay)
}
}
// isConnectionCloseRequest reports whether req should use its own
// connection for a single request and then close the connection.
func isConnectionCloseRequest(req *http.Request) bool {
return req.Close || httpguts.HeaderValuesContainsToken(req.Header["Connection"], "close")
}
// registerHTTPSProtocol calls Transport.RegisterProtocol but
// converting panics into errors.
func registerHTTPSProtocol(t *http.Transport, rt noDialH2RoundTripper) (err error) {
defer func() {
if e := recover(); e != nil {
err = fmt.Errorf("%v", e)
}
}()
t.RegisterProtocol("https", rt)
return nil
}
// noDialH2RoundTripper is a RoundTripper which only tries to complete the request
// if there's already has a cached connection to the host.
// (The field is exported so it can be accessed via reflect from net/http; tested
// by TestNoDialH2RoundTripperType)
type noDialH2RoundTripper struct{ *Transport }
func (rt noDialH2RoundTripper) RoundTrip(req *http.Request) (*http.Response, error) {
res, err := rt.Transport.RoundTrip(req)
if isNoCachedConnError(err) {
return nil, http.ErrSkipAltProtocol
}
return res, err
}
func (t *Transport) idleConnTimeout() time.Duration {
if t.t1 != nil {
return t.t1.IdleConnTimeout
}
return 0
}
func traceGetConn(req *http.Request, hostPort string) {
trace := httptrace.ContextClientTrace(req.Context())
if trace == nil || trace.GetConn == nil {
return
}
trace.GetConn(hostPort)
}
func traceGotConn(req *http.Request, cc *ClientConn, reused bool) {
trace := httptrace.ContextClientTrace(req.Context())
if trace == nil || trace.GotConn == nil {
return
}
ci := httptrace.GotConnInfo{Conn: cc.tconn}
ci.Reused = reused
cc.mu.Lock()
ci.WasIdle = len(cc.streams) == 0 && reused
if ci.WasIdle && !cc.lastActive.IsZero() {
ci.IdleTime = time.Now().Sub(cc.lastActive)
}
cc.mu.Unlock()
trace.GotConn(ci)
}
func traceWroteHeaders(trace *httptrace.ClientTrace) {
if trace != nil && trace.WroteHeaders != nil {
trace.WroteHeaders()
}
}
func traceGot100Continue(trace *httptrace.ClientTrace) {
if trace != nil && trace.Got100Continue != nil {
trace.Got100Continue()
}
}
func traceWait100Continue(trace *httptrace.ClientTrace) {
if trace != nil && trace.Wait100Continue != nil {
trace.Wait100Continue()
}
}
func traceWroteRequest(trace *httptrace.ClientTrace, err error) {
if trace != nil && trace.WroteRequest != nil {
trace.WroteRequest(httptrace.WroteRequestInfo{Err: err})
}
}
func traceFirstResponseByte(trace *httptrace.ClientTrace) {
if trace != nil && trace.GotFirstResponseByte != nil {
trace.GotFirstResponseByte()
}
}