func Logf(ctx netcontext.Context, level int64, format string, args ...interface{}) {
if f, ok := ctx.Value(&logOverrideKey).(logOverrideFunc); ok {
f(level, format, args...)
return
}
logf(fromContext(ctx), level, format, args...)
}
// NewClientStream creates a new Stream for the client side. This is called
// by generated code.
func NewClientStream(ctx context.Context, desc *StreamDesc, cc *ClientConn, method string, opts ...CallOption) (ClientStream, error) {
var (
t transport.ClientTransport
err error
)
t, err = cc.dopts.picker.Pick(ctx)
if err != nil {
return nil, toRPCErr(err)
}
// TODO(zhaoq): CallOption is omitted. Add support when it is needed.
callHdr := &transport.CallHdr{
Host: cc.authority,
Method: method,
Flush: desc.ServerStreams && desc.ClientStreams,
}
if cc.dopts.cp != nil {
callHdr.SendCompress = cc.dopts.cp.Type()
}
cs := &clientStream{
desc: desc,
codec: cc.dopts.codec,
cp: cc.dopts.cp,
dc: cc.dopts.dc,
tracing: EnableTracing,
}
if cc.dopts.cp != nil {
callHdr.SendCompress = cc.dopts.cp.Type()
cs.cbuf = new(bytes.Buffer)
}
if cs.tracing {
cs.trInfo.tr = trace.New("grpc.Sent."+methodFamily(method), method)
cs.trInfo.firstLine.client = true
if deadline, ok := ctx.Deadline(); ok {
cs.trInfo.firstLine.deadline = deadline.Sub(time.Now())
}
cs.trInfo.tr.LazyLog(&cs.trInfo.firstLine, false)
ctx = trace.NewContext(ctx, cs.trInfo.tr)
}
s, err := t.NewStream(ctx, callHdr)
if err != nil {
cs.finish(err)
return nil, toRPCErr(err)
}
cs.t = t
cs.s = s
cs.p = &parser{s: s}
// Listen on ctx.Done() to detect cancellation when there is no pending
// I/O operations on this stream.
go func() {
select {
case <-t.Error():
// Incur transport error, simply exit.
case <-s.Context().Done():
err := s.Context().Err()
cs.finish(err)
cs.closeTransportStream(transport.ContextErr(err))
}
}()
return cs, nil
}
// WaitForStateChange blocks until the state changes to something other than the sourceState.
func (cc *Conn) WaitForStateChange(ctx context.Context, sourceState ConnectivityState) (ConnectivityState, error) {
cc.mu.Lock()
defer cc.mu.Unlock()
if sourceState != cc.state {
return cc.state, nil
}
done := make(chan struct{})
var err error
go func() {
select {
case <-ctx.Done():
cc.mu.Lock()
err = ctx.Err()
cc.stateCV.Broadcast()
cc.mu.Unlock()
case <-done:
}
}()
defer close(done)
for sourceState == cc.state {
cc.stateCV.Wait()
if err != nil {
return cc.state, err
}
}
return cc.state, nil
}
// Wait blocks until i) the new transport is up or ii) ctx is done or iii) cc is closed.
func (cc *Conn) Wait(ctx context.Context) (transport.ClientTransport, error) {
for {
cc.mu.Lock()
switch {
case cc.state == Shutdown:
cc.mu.Unlock()
return nil, ErrClientConnClosing
case cc.state == Ready:
cc.mu.Unlock()
return cc.transport, nil
default:
ready := cc.ready
if ready == nil {
ready = make(chan struct{})
cc.ready = ready
}
cc.mu.Unlock()
select {
case <-ctx.Done():
return nil, transport.ContextErr(ctx.Err())
// Wait until the new transport is ready or failed.
case <-ready:
}
}
}
}
func contextDone(ctx context.Context) bool {
select {
case <-ctx.Done():
return true
default:
return false
}
}
func WithCallOverride(ctx netcontext.Context, f CallOverrideFunc) netcontext.Context {
// We avoid appending to any existing call override
// so we don't risk overwriting a popped stack below.
var cofs []CallOverrideFunc
if uf, ok := ctx.Value(&callOverrideKey).([]CallOverrideFunc); ok {
cofs = append(cofs, uf...)
}
cofs = append(cofs, f)
return netcontext.WithValue(ctx, &callOverrideKey, cofs)
}
// wait blocks until it can receive from ctx.Done, closing, or proceed.
// If it receives from ctx.Done, it returns 0, the StreamError for ctx.Err.
// If it receives from closing, it returns 0, ErrConnClosing.
// If it receives from proceed, it returns the received integer, nil.
func wait(ctx context.Context, closing <-chan struct{}, proceed <-chan int) (int, error) {
select {
case <-ctx.Done():
return 0, ContextErr(ctx.Err())
case <-closing:
return 0, ErrConnClosing
case i := <-proceed:
return i, nil
}
}
func callOverrideFromContext(ctx netcontext.Context) (CallOverrideFunc, netcontext.Context, bool) {
cofs, _ := ctx.Value(&callOverrideKey).([]CallOverrideFunc)
if len(cofs) == 0 {
return nil, nil, false
}
// We found a list of overrides; grab the last, and reconstitute a
// context that will hide it.
f := cofs[len(cofs)-1]
ctx = netcontext.WithValue(ctx, &callOverrideKey, cofs[:len(cofs)-1])
return f, ctx, true
}
func (c *ProtoClient) Call(ctx context.Context, method string, req, resp proto.Message) error {
payload, err := proto.Marshal(req)
if err != nil {
return err
}
httpReq, err := http.NewRequest("POST", c.endpoint+method, bytes.NewReader(payload))
if err != nil {
return err
}
httpReq.Header.Set("Content-Type", "application/x-protobuf")
if ua := c.userAgent; ua != "" {
httpReq.Header.Set("User-Agent", ua)
}
errc := make(chan error, 1)
cancel := makeReqCancel(httpReq)
go func() {
r, err := c.client.Do(httpReq)
if err != nil {
errc <- err
return
}
defer r.Body.Close()
body, err := ioutil.ReadAll(r.Body)
if r.StatusCode != http.StatusOK {
err = &ErrHTTP{
StatusCode: r.StatusCode,
Body: body,
err: err,
}
}
if err != nil {
errc <- err
return
}
errc <- proto.Unmarshal(body, resp)
}()
select {
case <-ctx.Done():
cancel(c.client.Transport) // Cancel the HTTP request.
return ctx.Err()
case err := <-errc:
return err
}
}
func ContextClient(ctx context.Context) (*http.Client, error) {
if ctx != nil {
if hc, ok := ctx.Value(HTTPClient).(*http.Client); ok {
return hc, nil
}
}
for _, fn := range contextClientFuncs {
c, err := fn(ctx)
if err != nil {
return nil, err
}
if c != nil {
return c, nil
}
}
return http.DefaultClient, nil
}
// Do sends an HTTP request with the provided http.Client and returns an HTTP response.
// If the client is nil, http.DefaultClient is used.
// If the context is canceled or times out, ctx.Err() will be returned.
func Do(ctx context.Context, client *http.Client, req *http.Request) (*http.Response, error) {
if client == nil {
client = http.DefaultClient
}
// Request cancelation changed in Go 1.5, see cancelreq.go and cancelreq_go14.go.
cancel := canceler(client, req)
type responseAndError struct {
resp *http.Response
err error
}
result := make(chan responseAndError, 1)
go func() {
resp, err := client.Do(req)
testHookDoReturned()
result <- responseAndError{resp, err}
}()
var resp *http.Response
select {
case <-ctx.Done():
testHookContextDoneBeforeHeaders()
cancel()
// Clean up after the goroutine calling client.Do:
go func() {
if r := <-result; r.resp != nil {
testHookDidBodyClose()
r.resp.Body.Close()
}
}()
return nil, ctx.Err()
case r := <-result:
var err error
resp, err = r.resp, r.err
if err != nil {
return resp, err
}
}
c := make(chan struct{})
go func() {
select {
case <-ctx.Done():
cancel()
case <-c:
// The response's Body is closed.
}
}()
resp.Body = ¬ifyingReader{resp.Body, c}
return resp, nil
}
func Call(ctx netcontext.Context, service, method string, in, out proto.Message) error {
if f, ctx, ok := callOverrideFromContext(ctx); ok {
return f(ctx, service, method, in, out)
}
// Handle already-done contexts quickly.
select {
case <-ctx.Done():
return ctx.Err()
default:
}
c := fromContext(ctx)
if c == nil {
// Give a good error message rather than a panic lower down.
return errors.New("not an App Engine context")
}
// Apply transaction modifications if we're in a transaction.
if t := transactionFromContext(ctx); t != nil {
if t.finished {
return errors.New("transaction context has expired")
}
applyTransaction(in, &t.transaction)
}
var opts *appengine_internal.CallOptions
if d, ok := ctx.Deadline(); ok {
opts = &appengine_internal.CallOptions{
Timeout: d.Sub(time.Now()),
}
}
err := c.Call(service, method, in, out, opts)
switch v := err.(type) {
case *appengine_internal.APIError:
return &APIError{
Service: v.Service,
Detail: v.Detail,
Code: v.Code,
}
case *appengine_internal.CallError:
return &CallError{
Detail: v.Detail,
Code: v.Code,
Timeout: v.Timeout,
}
}
return err
}
// Upload starts the process of a resumable upload with a cancellable context.
// It retries using the provided back off strategy until cancelled or the
// strategy indicates to stop retrying.
// It is called from the auto-generated API code and is not visible to the user.
// rx is private to the auto-generated API code.
// Exactly one of resp or err will be nil. If resp is non-nil, the caller must call resp.Body.Close.
func (rx *ResumableUpload) Upload(ctx context.Context) (resp *http.Response, err error) {
var pause time.Duration
backoff := rx.Backoff
if backoff == nil {
backoff = DefaultBackoffStrategy()
}
for {
// Ensure that we return in the case of cancelled context, even if pause is 0.
if contextDone(ctx) {
return nil, ctx.Err()
}
select {
case <-ctx.Done():
return nil, ctx.Err()
case <-time.After(pause):
}
resp, err = rx.transferChunk(ctx)
// It's possible for err and resp to both be non-nil here, but we expose a simpler
// contract to our callers: exactly one of resp and err will be non-nil. This means
// that any response body must be closed here before returning a non-nil error.
if err != nil {
if resp != nil && resp.Body != nil {
resp.Body.Close()
}
return nil, err
}
if resp.StatusCode == http.StatusCreated || resp.StatusCode == http.StatusOK {
return resp, nil
}
if resp.StatusCode == statusResumeIncomplete {
pause = 0
backoff.Reset()
} else {
var retry bool
pause, retry = backoff.Pause()
if !retry {
// Return the last response with its failing HTTP code.
return resp, nil
}
}
resp.Body.Close()
}
}
func transactionFromContext(ctx netcontext.Context) *transaction {
t, _ := ctx.Value(&transactionKey).(*transaction)
return t
}
func fromContext(ctx netcontext.Context) appengine.Context {
c, _ := ctx.Value(&contextKey).(appengine.Context)
return c
}
// ctxNamespace returns the active namespace for a context.
// It defaults to "" if no namespace was specified.
func ctxNamespace(ctx context.Context) string {
v, _ := ctx.Value(nsKey{}).(string)
return v
}
// FromContext returns the peer information in ctx if it exists.
func FromContext(ctx context.Context) (p *Peer, ok bool) {
p, ok = ctx.Value(peerKey{}).(*Peer)
return
}
func Call(ctx netcontext.Context, service, method string, in, out proto.Message) error {
if f, ctx, ok := callOverrideFromContext(ctx); ok {
return f(ctx, service, method, in, out)
}
// Handle already-done contexts quickly.
select {
case <-ctx.Done():
return ctx.Err()
default:
}
c := fromContext(ctx)
if c == nil {
// Give a good error message rather than a panic lower down.
return errors.New("not an App Engine context")
}
// Apply transaction modifications if we're in a transaction.
if t := transactionFromContext(ctx); t != nil {
if t.finished {
return errors.New("transaction context has expired")
}
applyTransaction(in, &t.transaction)
}
// Default RPC timeout is 60s.
timeout := 60 * time.Second
if deadline, ok := ctx.Deadline(); ok {
timeout = deadline.Sub(time.Now())
}
data, err := proto.Marshal(in)
if err != nil {
return err
}
ticket := c.req.Header.Get(ticketHeader)
req := &remotepb.Request{
ServiceName: &service,
Method: &method,
Request: data,
RequestId: &ticket,
}
hreqBody, err := proto.Marshal(req)
if err != nil {
return err
}
hrespBody, err := c.post(hreqBody, timeout)
if err != nil {
return err
}
res := &remotepb.Response{}
if err := proto.Unmarshal(hrespBody, res); err != nil {
return err
}
if res.RpcError != nil {
ce := &CallError{
Detail: res.RpcError.GetDetail(),
Code: *res.RpcError.Code,
}
switch remotepb.RpcError_ErrorCode(ce.Code) {
case remotepb.RpcError_CANCELLED, remotepb.RpcError_DEADLINE_EXCEEDED:
ce.Timeout = true
}
return ce
}
if res.ApplicationError != nil {
return &APIError{
Service: *req.ServiceName,
Detail: res.ApplicationError.GetDetail(),
Code: *res.ApplicationError.Code,
}
}
if res.Exception != nil || res.JavaException != nil {
// This shouldn't happen, but let's be defensive.
return &CallError{
Detail: "service bridge returned exception",
Code: int32(remotepb.RpcError_UNKNOWN),
}
}
return proto.Unmarshal(res.Response, out)
}
// FromContext returns the Trace bound to the context, if any.
func FromContext(ctx context.Context) (tr Trace, ok bool) {
tr, ok = ctx.Value(contextKey).(Trace)
return
}
// cc returns the internal *cloudContext (cc) state for a context.Context.
// It panics if the user did it wrong.
func cc(ctx context.Context) *cloudContext {
if c, ok := ctx.Value(contextKey{}).(*cloudContext); ok {
return c
}
panic("invalid context.Context type; it should be created with cloud.NewContext")
}
func NamespaceFromContext(ctx netcontext.Context) string {
// If there's no namespace, return the empty string.
ns, _ := ctx.Value(&namespaceKey).(string)
return ns
}
// Invoke is called by the generated code. It sends the RPC request on the
// wire and returns after response is received.
func Invoke(ctx context.Context, method string, args, reply interface{}, cc *ClientConn, opts ...CallOption) (err error) {
var c callInfo
for _, o := range opts {
if err := o.before(&c); err != nil {
return toRPCErr(err)
}
}
defer func() {
for _, o := range opts {
o.after(&c)
}
}()
if EnableTracing {
c.traceInfo.tr = trace.New("grpc.Sent."+methodFamily(method), method)
defer c.traceInfo.tr.Finish()
c.traceInfo.firstLine.client = true
if deadline, ok := ctx.Deadline(); ok {
c.traceInfo.firstLine.deadline = deadline.Sub(time.Now())
}
c.traceInfo.tr.LazyLog(&c.traceInfo.firstLine, false)
// TODO(dsymonds): Arrange for c.traceInfo.firstLine.remoteAddr to be set.
defer func() {
if err != nil {
c.traceInfo.tr.LazyLog(&fmtStringer{"%v", []interface{}{err}}, true)
c.traceInfo.tr.SetError()
}
}()
}
topts := &transport.Options{
Last: true,
Delay: false,
}
var (
lastErr error // record the error that happened
)
for {
var (
err error
t transport.ClientTransport
stream *transport.Stream
)
// TODO(zhaoq): Need a formal spec of retry strategy for non-failfast rpcs.
if lastErr != nil && c.failFast {
return toRPCErr(lastErr)
}
callHdr := &transport.CallHdr{
Host: cc.authority,
Method: method,
}
if cc.dopts.cp != nil {
callHdr.SendCompress = cc.dopts.cp.Type()
}
t, err = cc.dopts.picker.Pick(ctx)
if err != nil {
if lastErr != nil {
// This was a retry; return the error from the last attempt.
return toRPCErr(lastErr)
}
return toRPCErr(err)
}
if c.traceInfo.tr != nil {
c.traceInfo.tr.LazyLog(&payload{sent: true, msg: args}, true)
}
stream, err = sendRequest(ctx, cc.dopts.codec, cc.dopts.cp, callHdr, t, args, topts)
if err != nil {
if _, ok := err.(transport.ConnectionError); ok {
lastErr = err
continue
}
if lastErr != nil {
return toRPCErr(lastErr)
}
return toRPCErr(err)
}
// Receive the response
lastErr = recvResponse(cc.dopts, t, &c, stream, reply)
if _, ok := lastErr.(transport.ConnectionError); ok {
continue
}
if c.traceInfo.tr != nil {
c.traceInfo.tr.LazyLog(&payload{sent: false, msg: reply}, true)
}
t.CloseStream(stream, lastErr)
if lastErr != nil {
return toRPCErr(lastErr)
}
return Errorf(stream.StatusCode(), stream.StatusDesc())
}
}
// NewStream creates a stream and register it into the transport as "active"
// streams.
func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (_ *Stream, err error) {
// Record the timeout value on the context.
var timeout time.Duration
if dl, ok := ctx.Deadline(); ok {
timeout = dl.Sub(time.Now())
if timeout <= 0 {
return nil, ContextErr(context.DeadlineExceeded)
}
}
pr := &peer.Peer{
Addr: t.conn.RemoteAddr(),
}
// Attach Auth info if there is any.
if t.authInfo != nil {
pr.AuthInfo = t.authInfo
}
ctx = peer.NewContext(ctx, pr)
authData := make(map[string]string)
for _, c := range t.authCreds {
// Construct URI required to get auth request metadata.
var port string
if pos := strings.LastIndex(t.target, ":"); pos != -1 {
// Omit port if it is the default one.
if t.target[pos+1:] != "443" {
port = ":" + t.target[pos+1:]
}
}
pos := strings.LastIndex(callHdr.Method, "/")
if pos == -1 {
return nil, StreamErrorf(codes.InvalidArgument, "transport: malformed method name: %q", callHdr.Method)
}
audience := "https://" + callHdr.Host + port + callHdr.Method[:pos]
data, err := c.GetRequestMetadata(ctx, audience)
if err != nil {
return nil, StreamErrorf(codes.InvalidArgument, "transport: %v", err)
}
for k, v := range data {
authData[k] = v
}
}
t.mu.Lock()
if t.state != reachable {
t.mu.Unlock()
return nil, ErrConnClosing
}
checkStreamsQuota := t.streamsQuota != nil
t.mu.Unlock()
if checkStreamsQuota {
sq, err := wait(ctx, t.shutdownChan, t.streamsQuota.acquire())
if err != nil {
return nil, err
}
// Returns the quota balance back.
if sq > 1 {
t.streamsQuota.add(sq - 1)
}
}
if _, err := wait(ctx, t.shutdownChan, t.writableChan); err != nil {
// t.streamsQuota will be updated when t.CloseStream is invoked.
return nil, err
}
t.mu.Lock()
if t.state != reachable {
t.mu.Unlock()
return nil, ErrConnClosing
}
s := t.newStream(ctx, callHdr)
t.activeStreams[s.id] = s
// This stream is not counted when applySetings(...) initialize t.streamsQuota.
// Reset t.streamsQuota to the right value.
var reset bool
if !checkStreamsQuota && t.streamsQuota != nil {
reset = true
}
t.mu.Unlock()
if reset {
t.streamsQuota.reset(-1)
}
// HPACK encodes various headers. Note that once WriteField(...) is
// called, the corresponding headers/continuation frame has to be sent
// because hpack.Encoder is stateful.
t.hBuf.Reset()
t.hEnc.WriteField(hpack.HeaderField{Name: ":method", Value: "POST"})
t.hEnc.WriteField(hpack.HeaderField{Name: ":scheme", Value: t.scheme})
t.hEnc.WriteField(hpack.HeaderField{Name: ":path", Value: callHdr.Method})
t.hEnc.WriteField(hpack.HeaderField{Name: ":authority", Value: callHdr.Host})
t.hEnc.WriteField(hpack.HeaderField{Name: "content-type", Value: "application/grpc"})
t.hEnc.WriteField(hpack.HeaderField{Name: "user-agent", Value: t.userAgent})
t.hEnc.WriteField(hpack.HeaderField{Name: "te", Value: "trailers"})
if callHdr.SendCompress != "" {
t.hEnc.WriteField(hpack.HeaderField{Name: "grpc-encoding", Value: callHdr.SendCompress})
}
if timeout > 0 {
t.hEnc.WriteField(hpack.HeaderField{Name: "grpc-timeout", Value: timeoutEncode(timeout)})
}
for k, v := range authData {
t.hEnc.WriteField(hpack.HeaderField{Name: k, Value: v})
}
var (
hasMD bool
endHeaders bool
)
if md, ok := metadata.FromContext(ctx); ok {
hasMD = true
for k, v := range md {
for _, entry := range v {
t.hEnc.WriteField(hpack.HeaderField{Name: k, Value: entry})
}
}
}
first := true
// Sends the headers in a single batch even when they span multiple frames.
for !endHeaders {
size := t.hBuf.Len()
if size > http2MaxFrameLen {
size = http2MaxFrameLen
} else {
endHeaders = true
}
var flush bool
if endHeaders && (hasMD || callHdr.Flush) {
flush = true
}
if first {
// Sends a HeadersFrame to server to start a new stream.
p := http2.HeadersFrameParam{
StreamID: s.id,
BlockFragment: t.hBuf.Next(size),
EndStream: false,
EndHeaders: endHeaders,
}
// Do a force flush for the buffered frames iff it is the last headers frame
// and there is header metadata to be sent. Otherwise, there is flushing until
// the corresponding data frame is written.
err = t.framer.writeHeaders(flush, p)
first = false
} else {
// Sends Continuation frames for the leftover headers.
err = t.framer.writeContinuation(flush, s.id, endHeaders, t.hBuf.Next(size))
}
if err != nil {
t.notifyError(err)
return nil, ConnectionErrorf("transport: %v", err)
}
}
t.writableChan <- 0
return s, nil
}
// FullyQualifiedAppID returns the fully-qualified application ID.
// This may contain a partition prefix (e.g. "s~" for High Replication apps),
// or a domain prefix (e.g. "example.com:").
func FullyQualifiedAppID(ctx netcontext.Context) string {
if id, ok := ctx.Value(&appIDOverrideKey).(string); ok {
return id
}
return fullyQualifiedAppID(ctx)
}
// FromContext returns the MD in ctx if it exists.
func FromContext(ctx context.Context) (md MD, ok bool) {
md, ok = ctx.Value(mdKey{}).(MD)
return
}
func fromContext(ctx netcontext.Context) *context {
c, _ := ctx.Value(&contextKey).(*context)
return c
}
// StreamFromContext returns the stream saved in ctx.
func StreamFromContext(ctx context.Context) (s *Stream, ok bool) {
s, ok = ctx.Value(streamKey).(*Stream)
return
}