Upgrade to 0.12

1 files changed, 161 insertions, 0 deletions

diff --git a/vendor/github.com/googleapis/gax-go/v2/call_option.go b/vendor/github.com/googleapis/gax-go/v2/call_option.go
new file mode 100644
index 0000000..b1d53dd
--- /dev/null
+++ b/vendor/github.com/googleapis/gax-go/v2/call_option.go
@@ -0,0 +1,161 @@
+// Copyright 2016, Google Inc.
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package gax
+
+import (
+        "math/rand"
+        "time"
+
+        "google.golang.org/grpc"
+        "google.golang.org/grpc/codes"
+        "google.golang.org/grpc/status"
+)
+
+// CallOption is an option used by Invoke to control behaviors of RPC calls.
+// CallOption works by modifying relevant fields of CallSettings.
+type CallOption interface {
+        // Resolve applies the option by modifying cs.
+        Resolve(cs *CallSettings)
+}
+
+// Retryer is used by Invoke to determine retry behavior.
+type Retryer interface {
+        // Retry reports whether a request should be retriedand how long to pause before retrying
+        // if the previous attempt returned with err. Invoke never calls Retry with nil error.
+        Retry(err error) (pause time.Duration, shouldRetry bool)
+}
+
+type retryerOption func() Retryer
+
+func (o retryerOption) Resolve(s *CallSettings) {
+        s.Retry = o
+}
+
+// WithRetry sets CallSettings.Retry to fn.
+func WithRetry(fn func() Retryer) CallOption {
+        return retryerOption(fn)
+}
+
+// OnCodes returns a Retryer that retries if and only if
+// the previous attempt returns a GRPC error whose error code is stored in cc.
+// Pause times between retries are specified by bo.
+//
+// bo is only used for its parameters; each Retryer has its own copy.
+func OnCodes(cc []codes.Code, bo Backoff) Retryer {
+        return &boRetryer{
+                backoff: bo,
+                codes:   append([]codes.Code(nil), cc...),
+        }
+}
+
+type boRetryer struct {
+        backoff Backoff
+        codes   []codes.Code
+}
+
+func (r *boRetryer) Retry(err error) (time.Duration, bool) {
+        st, ok := status.FromError(err)
+        if !ok {
+                return 0, false
+        }
+        c := st.Code()
+        for _, rc := range r.codes {
+                if c == rc {
+                        return r.backoff.Pause(), true
+                }
+        }
+        return 0, false
+}
+
+// Backoff implements exponential backoff.
+// The wait time between retries is a random value between 0 and the "retry envelope".
+// The envelope starts at Initial and increases by the factor of Multiplier every retry,
+// but is capped at Max.
+type Backoff struct {
+        // Initial is the initial value of the retry envelope, defaults to 1 second.
+        Initial time.Duration
+
+        // Max is the maximum value of the retry envelope, defaults to 30 seconds.
+        Max time.Duration
+
+        // Multiplier is the factor by which the retry envelope increases.
+        // It should be greater than 1 and defaults to 2.
+        Multiplier float64
+
+        // cur is the current retry envelope
+        cur time.Duration
+}
+
+// Pause returns the next time.Duration that the caller should use to backoff.
+func (bo *Backoff) Pause() time.Duration {
+        if bo.Initial == 0 {
+                bo.Initial = time.Second
+        }
+        if bo.cur == 0 {
+                bo.cur = bo.Initial
+        }
+        if bo.Max == 0 {
+                bo.Max = 30 * time.Second
+        }
+        if bo.Multiplier < 1 {
+                bo.Multiplier = 2
+        }
+        // Select a duration between 1ns and the current max. It might seem
+        // counterintuitive to have so much jitter, but
+        // https://www.awsarchitectureblog.com/2015/03/backoff.html argues that
+        // that is the best strategy.
+        d := time.Duration(1 + rand.Int63n(int64(bo.cur)))
+        bo.cur = time.Duration(float64(bo.cur) * bo.Multiplier)
+        if bo.cur > bo.Max {
+                bo.cur = bo.Max
+        }
+        return d
+}
+
+type grpcOpt []grpc.CallOption
+
+func (o grpcOpt) Resolve(s *CallSettings) {
+        s.GRPC = o
+}
+
+// WithGRPCOptions allows passing gRPC call options during client creation.
+func WithGRPCOptions(opt ...grpc.CallOption) CallOption {
+        return grpcOpt(append([]grpc.CallOption(nil), opt...))
+}
+
+// CallSettings allow fine-grained control over how calls are made.
+type CallSettings struct {
+        // Retry returns a Retryer to be used to control retry logic of a method call.
+        // If Retry is nil or the returned Retryer is nil, the call will not be retried.
+        Retry func() Retryer
+
+        // CallOptions to be forwarded to GRPC.
+        GRPC []grpc.CallOption
+}