initial add - go fmt on grpc
Change-Id: Ib0afadd2fe5571d1456a091f94f5644458f7d3f4
diff --git a/vendor/google.golang.org/grpc/picker_wrapper.go b/vendor/google.golang.org/grpc/picker_wrapper.go
new file mode 100644
index 0000000..45baa2a
--- /dev/null
+++ b/vendor/google.golang.org/grpc/picker_wrapper.go
@@ -0,0 +1,197 @@
+/*
+ *
+ * Copyright 2017 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package grpc
+
+import (
+ "context"
+ "io"
+ "sync"
+
+ "google.golang.org/grpc/balancer"
+ "google.golang.org/grpc/codes"
+ "google.golang.org/grpc/grpclog"
+ "google.golang.org/grpc/internal/channelz"
+ "google.golang.org/grpc/internal/transport"
+ "google.golang.org/grpc/status"
+)
+
+// pickerWrapper is a wrapper of balancer.Picker. It blocks on certain pick
+// actions and unblock when there's a picker update.
+type pickerWrapper struct {
+ mu sync.Mutex
+ done bool
+ blockingCh chan struct{}
+ picker balancer.Picker
+
+ // The latest connection happened.
+ connErrMu sync.Mutex
+ connErr error
+}
+
+func newPickerWrapper() *pickerWrapper {
+ bp := &pickerWrapper{blockingCh: make(chan struct{})}
+ return bp
+}
+
+func (bp *pickerWrapper) updateConnectionError(err error) {
+ bp.connErrMu.Lock()
+ bp.connErr = err
+ bp.connErrMu.Unlock()
+}
+
+func (bp *pickerWrapper) connectionError() error {
+ bp.connErrMu.Lock()
+ err := bp.connErr
+ bp.connErrMu.Unlock()
+ return err
+}
+
+// updatePicker is called by UpdateBalancerState. It unblocks all blocked pick.
+func (bp *pickerWrapper) updatePicker(p balancer.Picker) {
+ bp.mu.Lock()
+ if bp.done {
+ bp.mu.Unlock()
+ return
+ }
+ bp.picker = p
+ // bp.blockingCh should never be nil.
+ close(bp.blockingCh)
+ bp.blockingCh = make(chan struct{})
+ bp.mu.Unlock()
+}
+
+func doneChannelzWrapper(acw *acBalancerWrapper, done func(balancer.DoneInfo)) func(balancer.DoneInfo) {
+ acw.mu.Lock()
+ ac := acw.ac
+ acw.mu.Unlock()
+ ac.incrCallsStarted()
+ return func(b balancer.DoneInfo) {
+ if b.Err != nil && b.Err != io.EOF {
+ ac.incrCallsFailed()
+ } else {
+ ac.incrCallsSucceeded()
+ }
+ if done != nil {
+ done(b)
+ }
+ }
+}
+
+// pick returns the transport that will be used for the RPC.
+// It may block in the following cases:
+// - there's no picker
+// - the current picker returns ErrNoSubConnAvailable
+// - the current picker returns other errors and failfast is false.
+// - the subConn returned by the current picker is not READY
+// When one of these situations happens, pick blocks until the picker gets updated.
+func (bp *pickerWrapper) pick(ctx context.Context, failfast bool, opts balancer.PickOptions) (transport.ClientTransport, func(balancer.DoneInfo), error) {
+ var ch chan struct{}
+
+ for {
+ bp.mu.Lock()
+ if bp.done {
+ bp.mu.Unlock()
+ return nil, nil, ErrClientConnClosing
+ }
+
+ if bp.picker == nil {
+ ch = bp.blockingCh
+ }
+ if ch == bp.blockingCh {
+ // This could happen when either:
+ // - bp.picker is nil (the previous if condition), or
+ // - has called pick on the current picker.
+ bp.mu.Unlock()
+ select {
+ case <-ctx.Done():
+ if connectionErr := bp.connectionError(); connectionErr != nil {
+ switch ctx.Err() {
+ case context.DeadlineExceeded:
+ return nil, nil, status.Errorf(codes.DeadlineExceeded, "latest connection error: %v", connectionErr)
+ case context.Canceled:
+ return nil, nil, status.Errorf(codes.Canceled, "latest connection error: %v", connectionErr)
+ }
+ }
+ return nil, nil, ctx.Err()
+ case <-ch:
+ }
+ continue
+ }
+
+ ch = bp.blockingCh
+ p := bp.picker
+ bp.mu.Unlock()
+
+ subConn, done, err := p.Pick(ctx, opts)
+
+ if err != nil {
+ switch err {
+ case balancer.ErrNoSubConnAvailable:
+ continue
+ case balancer.ErrTransientFailure:
+ if !failfast {
+ continue
+ }
+ return nil, nil, status.Errorf(codes.Unavailable, "%v, latest connection error: %v", err, bp.connectionError())
+ case context.DeadlineExceeded:
+ return nil, nil, status.Error(codes.DeadlineExceeded, err.Error())
+ case context.Canceled:
+ return nil, nil, status.Error(codes.Canceled, err.Error())
+ default:
+ if _, ok := status.FromError(err); ok {
+ return nil, nil, err
+ }
+ // err is some other error.
+ return nil, nil, status.Error(codes.Unknown, err.Error())
+ }
+ }
+
+ acw, ok := subConn.(*acBalancerWrapper)
+ if !ok {
+ grpclog.Error("subconn returned from pick is not *acBalancerWrapper")
+ continue
+ }
+ if t, ok := acw.getAddrConn().getReadyTransport(); ok {
+ if channelz.IsOn() {
+ return t, doneChannelzWrapper(acw, done), nil
+ }
+ return t, done, nil
+ }
+ if done != nil {
+ // Calling done with nil error, no bytes sent and no bytes received.
+ // DoneInfo with default value works.
+ done(balancer.DoneInfo{})
+ }
+ grpclog.Infof("blockingPicker: the picked transport is not ready, loop back to repick")
+ // If ok == false, ac.state is not READY.
+ // A valid picker always returns READY subConn. This means the state of ac
+ // just changed, and picker will be updated shortly.
+ // continue back to the beginning of the for loop to repick.
+ }
+}
+
+func (bp *pickerWrapper) close() {
+ bp.mu.Lock()
+ defer bp.mu.Unlock()
+ if bp.done {
+ return
+ }
+ bp.done = true
+ close(bp.blockingCh)
+}