add v2 directory (#59)
add v2 directory
This commit was generated by copying the contents of the parent directory into
the v2 directory.
This commit supercedes https://github.com/googleapis/gax-go/pull/58 and is one
of two in a series of commits to add Go module support to gax.
Unfortunately, gax-go already has a v2.0.0 tag. So, per [1] we create a v2/
subdirectory, copy all the v1 code, and create a v2 go.mod in the subdirectory.
Then, after this commit is merged, the commit will be tagged v2.0.1. This is a
combination of the "Major Branch" and the "Major Subdirectory" approaches
mentioned in [1].
1: https://github.com/golang/go/wiki/Modules#releasing-modules-v2-or-higher
diff --git a/v2/call_option.go b/v2/call_option.go
new file mode 100644
index 0000000..7b62164
--- /dev/null
+++ b/v2/call_option.go
@@ -0,0 +1,157 @@
+// 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
+}
+
+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 zero 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(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
+}
+
+func WithGRPCOptions(opt ...grpc.CallOption) CallOption {
+ return grpcOpt(append([]grpc.CallOption(nil), opt...))
+}
+
+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
+}
diff --git a/v2/call_option_test.go b/v2/call_option_test.go
new file mode 100644
index 0000000..6f81305
--- /dev/null
+++ b/v2/call_option_test.go
@@ -0,0 +1,88 @@
+// 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 (
+ "testing"
+ "time"
+
+ "google.golang.org/grpc/codes"
+ "google.golang.org/grpc/status"
+)
+
+var _ Retryer = &boRetryer{}
+
+func TestBackofDefault(t *testing.T) {
+ backoff := Backoff{}
+
+ max := []time.Duration{1, 2, 4, 8, 16, 30, 30, 30, 30, 30}
+ for i, m := range max {
+ max[i] = m * time.Second
+ }
+
+ for i, w := range max {
+ if d := backoff.Pause(); d > w {
+ t.Errorf("Backoff duration should be at most %s, got %s", w, d)
+ } else if i < len(max)-1 && backoff.cur != max[i+1] {
+ t.Errorf("current envelope is %s, want %s", backoff.cur, max[i+1])
+ }
+ }
+}
+
+func TestBackoffExponential(t *testing.T) {
+ backoff := Backoff{Initial: 1, Max: 20, Multiplier: 2}
+ want := []time.Duration{1, 2, 4, 8, 16, 20, 20, 20, 20, 20}
+ for _, w := range want {
+ if d := backoff.Pause(); d > w {
+ t.Errorf("Backoff duration should be at most %s, got %s", w, d)
+ }
+ }
+}
+
+func TestOnCodes(t *testing.T) {
+ // Lint errors grpc.Errorf in 1.6. It mistakenly expects the first arg to Errorf to be a string.
+ errf := status.Errorf
+ apiErr := errf(codes.Unavailable, "")
+ tests := []struct {
+ c []codes.Code
+ retry bool
+ }{
+ {nil, false},
+ {[]codes.Code{codes.DeadlineExceeded}, false},
+ {[]codes.Code{codes.DeadlineExceeded, codes.Unavailable}, true},
+ {[]codes.Code{codes.Unavailable}, true},
+ }
+ for _, tst := range tests {
+ b := OnCodes(tst.c, Backoff{})
+ if _, retry := b.Retry(apiErr); retry != tst.retry {
+ t.Errorf("retriable codes: %v, error: %s, retry: %t, want %t", tst.c, apiErr, retry, tst.retry)
+ }
+ }
+}
diff --git a/v2/gax.go b/v2/gax.go
new file mode 100644
index 0000000..8b2900e
--- /dev/null
+++ b/v2/gax.go
@@ -0,0 +1,38 @@
+// 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 contains a set of modules which aid the development of APIs
+// for clients and servers based on gRPC and Google API conventions.
+//
+// Application code will rarely need to use this library directly.
+// However, code generated automatically from API definition files can use it
+// to simplify code generation and to provide more convenient and idiomatic API surfaces.
+package gax
+
+const Version = "2.0.0"
diff --git a/v2/go.mod b/v2/go.mod
new file mode 100644
index 0000000..c88c205
--- /dev/null
+++ b/v2/go.mod
@@ -0,0 +1,3 @@
+module github.com/googleapis/gax-go/v2
+
+require google.golang.org/grpc v1.16.0
diff --git a/v2/go.sum b/v2/go.sum
new file mode 100644
index 0000000..bad34ab
--- /dev/null
+++ b/v2/go.sum
@@ -0,0 +1,26 @@
+cloud.google.com/go v0.26.0/go.mod h1:aQUYkXzVsufM+DwF1aE+0xfcU+56JwCaLick0ClmMTw=
+github.com/client9/misspell v0.3.4/go.mod h1:qj6jICC3Q7zFZvVWo7KLAzC3yx5G7kyvSDkc90ppPyw=
+github.com/golang/glog v0.0.0-20160126235308-23def4e6c14b h1:VKtxabqXZkF25pY9ekfRL6a582T4P37/31XEstQ5p58=
+github.com/golang/glog v0.0.0-20160126235308-23def4e6c14b/go.mod h1:SBH7ygxi8pfUlaOkMMuAQtPIUF8ecWP5IEl/CR7VP2Q=
+github.com/golang/lint v0.0.0-20180702182130-06c8688daad7/go.mod h1:tluoj9z5200jBnyusfRPU2LqT6J+DAorxEvtC7LHB+E=
+github.com/golang/mock v1.1.1/go.mod h1:oTYuIxOrZwtPieC+H1uAHpcLFnEyAGVDL/k47Jfbm0A=
+github.com/golang/protobuf v1.2.0 h1:P3YflyNX/ehuJFLhxviNdFxQPkGK5cDcApsge1SqnvM=
+github.com/golang/protobuf v1.2.0/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
+github.com/kisielk/gotool v1.0.0/go.mod h1:XhKaO+MFFWcvkIS/tQcRk01m1F5IRFswLeQ+oQHNcck=
+golang.org/x/lint v0.0.0-20180702182130-06c8688daad7/go.mod h1:UVdnD1Gm6xHRNCYTkRU2/jEulfH38KcIWyp/GAMgvoE=
+golang.org/x/net v0.0.0-20180826012351-8a410e7b638d h1:g9qWBGx4puODJTMVyoPrpoxPFgVGd+z1DZwjfRu4d0I=
+golang.org/x/net v0.0.0-20180826012351-8a410e7b638d/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
+golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be/go.mod h1:N/0e6XlmueqKjAGxoOufVs8QHGRruUQn6yWY3a++T0U=
+golang.org/x/sync v0.0.0-20180314180146-1d60e4601c6f h1:wMNYb4v58l5UBM7MYRLPG6ZhfOqbKu7X5eyFl8ZhKvA=
+golang.org/x/sync v0.0.0-20180314180146-1d60e4601c6f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sys v0.0.0-20180830151530-49385e6e1522 h1:Ve1ORMCxvRmSXBwJK+t3Oy+V2vRW2OetUQBq4rJIkZE=
+golang.org/x/sys v0.0.0-20180830151530-49385e6e1522/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/text v0.3.0 h1:g61tztE5qeGQ89tm6NTjjM9VPIm088od1l6aSorWRWg=
+golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
+golang.org/x/tools v0.0.0-20180828015842-6cd1fcedba52/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
+google.golang.org/appengine v1.1.0/go.mod h1:EbEs0AVv82hx2wNQdGPgUI5lhzA/G0D9YwlJXL52JkM=
+google.golang.org/genproto v0.0.0-20180817151627-c66870c02cf8 h1:Nw54tB0rB7hY/N0NQvRW8DG4Yk3Q6T9cu9RcFQDu1tc=
+google.golang.org/genproto v0.0.0-20180817151627-c66870c02cf8/go.mod h1:JiN7NxoALGmiZfu7CAH4rXhgtRTLTxftemlI0sWmxmc=
+google.golang.org/grpc v1.16.0 h1:dz5IJGuC2BB7qXR5AyHNwAUBhZscK2xVez7mznh72sY=
+google.golang.org/grpc v1.16.0/go.mod h1:0JHn/cJsOMiMfNA9+DeHDlAU7KAAB5GDlYFpa9MZMio=
+honnef.co/go/tools v0.0.0-20180728063816-88497007e858/go.mod h1:rf3lG4BRIbNafJWhAfAdb/ePZxsR/4RtNHQocxwk9r4=
diff --git a/v2/header.go b/v2/header.go
new file mode 100644
index 0000000..d81455e
--- /dev/null
+++ b/v2/header.go
@@ -0,0 +1,24 @@
+package gax
+
+import "bytes"
+
+// XGoogHeader is for use by the Google Cloud Libraries only.
+//
+// XGoogHeader formats key-value pairs.
+// The resulting string is suitable for x-goog-api-client header.
+func XGoogHeader(keyval ...string) string {
+ if len(keyval) == 0 {
+ return ""
+ }
+ if len(keyval)%2 != 0 {
+ panic("gax.Header: odd argument count")
+ }
+ var buf bytes.Buffer
+ for i := 0; i < len(keyval); i += 2 {
+ buf.WriteByte(' ')
+ buf.WriteString(keyval[i])
+ buf.WriteByte('/')
+ buf.WriteString(keyval[i+1])
+ }
+ return buf.String()[1:]
+}
diff --git a/v2/header_test.go b/v2/header_test.go
new file mode 100644
index 0000000..05d8de6
--- /dev/null
+++ b/v2/header_test.go
@@ -0,0 +1,19 @@
+package gax
+
+import "testing"
+
+func TestXGoogHeader(t *testing.T) {
+ for _, tst := range []struct {
+ kv []string
+ want string
+ }{
+ {nil, ""},
+ {[]string{"abc", "def"}, "abc/def"},
+ {[]string{"abc", "def", "xyz", "123", "foo", ""}, "abc/def xyz/123 foo/"},
+ } {
+ got := XGoogHeader(tst.kv...)
+ if got != tst.want {
+ t.Errorf("Header(%q) = %q, want %q", tst.kv, got, tst.want)
+ }
+ }
+}
diff --git a/v2/invoke.go b/v2/invoke.go
new file mode 100644
index 0000000..cb5cd2a
--- /dev/null
+++ b/v2/invoke.go
@@ -0,0 +1,89 @@
+// 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 (
+ "context"
+ "time"
+)
+
+// A user defined call stub.
+type APICall func(context.Context, CallSettings) error
+
+// Invoke calls the given APICall,
+// performing retries as specified by opts, if any.
+func Invoke(ctx context.Context, call APICall, opts ...CallOption) error {
+ var settings CallSettings
+ for _, opt := range opts {
+ opt.Resolve(&settings)
+ }
+ return invoke(ctx, call, settings, Sleep)
+}
+
+// Sleep is similar to time.Sleep, but it can be interrupted by ctx.Done() closing.
+// If interrupted, Sleep returns ctx.Err().
+func Sleep(ctx context.Context, d time.Duration) error {
+ t := time.NewTimer(d)
+ select {
+ case <-ctx.Done():
+ t.Stop()
+ return ctx.Err()
+ case <-t.C:
+ return nil
+ }
+}
+
+type sleeper func(ctx context.Context, d time.Duration) error
+
+// invoke implements Invoke, taking an additional sleeper argument for testing.
+func invoke(ctx context.Context, call APICall, settings CallSettings, sp sleeper) error {
+ var retryer Retryer
+ for {
+ err := call(ctx, settings)
+ if err == nil {
+ return nil
+ }
+ if settings.Retry == nil {
+ return err
+ }
+ if retryer == nil {
+ if r := settings.Retry(); r != nil {
+ retryer = r
+ } else {
+ return err
+ }
+ }
+ if d, ok := retryer.Retry(err); !ok {
+ return err
+ } else if err = sp(ctx, d); err != nil {
+ return err
+ }
+ }
+}
diff --git a/v2/invoke_test.go b/v2/invoke_test.go
new file mode 100644
index 0000000..d476d14
--- /dev/null
+++ b/v2/invoke_test.go
@@ -0,0 +1,155 @@
+// 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 (
+ "context"
+ "errors"
+ "testing"
+ "time"
+)
+
+var canceledContext context.Context
+
+func init() {
+ ctx, cancel := context.WithCancel(context.Background())
+ cancel()
+ canceledContext = ctx
+}
+
+// recordSleeper is a test implementation of sleeper.
+type recordSleeper int
+
+func (s *recordSleeper) sleep(ctx context.Context, _ time.Duration) error {
+ *s++
+ return ctx.Err()
+}
+
+type boolRetryer bool
+
+func (r boolRetryer) Retry(err error) (time.Duration, bool) { return 0, bool(r) }
+
+func TestInvokeSuccess(t *testing.T) {
+ apiCall := func(context.Context, CallSettings) error { return nil }
+ var sp recordSleeper
+ err := invoke(context.Background(), apiCall, CallSettings{}, sp.sleep)
+
+ if err != nil {
+ t.Errorf("found error %s, want nil", err)
+ }
+ if sp != 0 {
+ t.Errorf("slept %d times, should not have slept since the call succeeded", int(sp))
+ }
+}
+
+func TestInvokeNoRetry(t *testing.T) {
+ apiErr := errors.New("foo error")
+ apiCall := func(context.Context, CallSettings) error { return apiErr }
+ var sp recordSleeper
+ err := invoke(context.Background(), apiCall, CallSettings{}, sp.sleep)
+
+ if err != apiErr {
+ t.Errorf("found error %s, want %s", err, apiErr)
+ }
+ if sp != 0 {
+ t.Errorf("slept %d times, should not have slept since retry is not specified", int(sp))
+ }
+}
+
+func TestInvokeNilRetry(t *testing.T) {
+ apiErr := errors.New("foo error")
+ apiCall := func(context.Context, CallSettings) error { return apiErr }
+ var settings CallSettings
+ WithRetry(func() Retryer { return nil }).Resolve(&settings)
+ var sp recordSleeper
+ err := invoke(context.Background(), apiCall, settings, sp.sleep)
+
+ if err != apiErr {
+ t.Errorf("found error %s, want %s", err, apiErr)
+ }
+ if sp != 0 {
+ t.Errorf("slept %d times, should not have slept since retry is not specified", int(sp))
+ }
+}
+
+func TestInvokeNeverRetry(t *testing.T) {
+ apiErr := errors.New("foo error")
+ apiCall := func(context.Context, CallSettings) error { return apiErr }
+ var settings CallSettings
+ WithRetry(func() Retryer { return boolRetryer(false) }).Resolve(&settings)
+ var sp recordSleeper
+ err := invoke(context.Background(), apiCall, settings, sp.sleep)
+
+ if err != apiErr {
+ t.Errorf("found error %s, want %s", err, apiErr)
+ }
+ if sp != 0 {
+ t.Errorf("slept %d times, should not have slept since retry is not specified", int(sp))
+ }
+}
+
+func TestInvokeRetry(t *testing.T) {
+ const target = 3
+
+ retryNum := 0
+ apiErr := errors.New("foo error")
+ apiCall := func(context.Context, CallSettings) error {
+ retryNum++
+ if retryNum < target {
+ return apiErr
+ }
+ return nil
+ }
+ var settings CallSettings
+ WithRetry(func() Retryer { return boolRetryer(true) }).Resolve(&settings)
+ var sp recordSleeper
+ err := invoke(context.Background(), apiCall, settings, sp.sleep)
+
+ if err != nil {
+ t.Errorf("found error %s, want nil, call should have succeeded after %d tries", err, target)
+ }
+ if sp != target-1 {
+ t.Errorf("retried %d times, want %d", int(sp), int(target-1))
+ }
+}
+
+func TestInvokeRetryTimeout(t *testing.T) {
+ apiErr := errors.New("foo error")
+ apiCall := func(context.Context, CallSettings) error { return apiErr }
+ var settings CallSettings
+ WithRetry(func() Retryer { return boolRetryer(true) }).Resolve(&settings)
+ var sp recordSleeper
+
+ err := invoke(canceledContext, apiCall, settings, sp.sleep)
+
+ if err != context.Canceled {
+ t.Errorf("found error %s, want %s", err, context.Canceled)
+ }
+}
