From e0a1ccb64a637673195804513902cba6b1d4e97c Mon Sep 17 00:00:00 2001 From: Niall Sheridan Date: Mon, 31 Oct 2016 16:36:17 +0000 Subject: Update dependencies --- vendor/github.com/googleapis/gax-go/call_option.go | 136 +++++++++++++++++++++ 1 file changed, 136 insertions(+) create mode 100644 vendor/github.com/googleapis/gax-go/call_option.go (limited to 'vendor/github.com/googleapis/gax-go/call_option.go') diff --git a/vendor/github.com/googleapis/gax-go/call_option.go b/vendor/github.com/googleapis/gax-go/call_option.go new file mode 100644 index 0000000..4ba1cdf --- /dev/null +++ b/vendor/github.com/googleapis/gax-go/call_option.go @@ -0,0 +1,136 @@ +// 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" +) + +// 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) { + c := grpc.Code(err) + 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 +} + +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 + } + d := time.Duration(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 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 +} -- cgit v1.2.3