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35 "golang.org/x/net/context"
38 // A user defined call stub.
39 type APICall func(context.Context) error
41 // Invoke calls the given APICall,
42 // performing retries as specified by opts, if any.
43 func Invoke(ctx context.Context, call APICall, opts ...CallOption) error {
44 var settings CallSettings
45 for _, opt := range opts {
46 opt.Resolve(&settings)
48 return invoke(ctx, call, settings, Sleep)
51 // Sleep is similar to time.Sleep, but it can be interrupted by ctx.Done() closing.
52 // If interrupted, Sleep returns ctx.Err().
53 func Sleep(ctx context.Context, d time.Duration) error {
64 type sleeper func(ctx context.Context, d time.Duration) error
66 // invoke implements Invoke, taking an additional sleeper argument for testing.
67 func invoke(ctx context.Context, call APICall, settings CallSettings, sp sleeper) error {
74 if settings.Retry == nil {
78 if r := settings.Retry(); r != nil {
84 if d, ok := retryer.Retry(err); !ok {
86 } else if err = sp(ctx, d); err != nil {