diff options
Diffstat (limited to 'vendor/github.com/goamz/goamz/aws/attempt.go')
-rw-r--r-- | vendor/github.com/goamz/goamz/aws/attempt.go | 74 |
1 files changed, 74 insertions, 0 deletions
diff --git a/vendor/github.com/goamz/goamz/aws/attempt.go b/vendor/github.com/goamz/goamz/aws/attempt.go new file mode 100644 index 000000000..c0654f5d8 --- /dev/null +++ b/vendor/github.com/goamz/goamz/aws/attempt.go @@ -0,0 +1,74 @@ +package aws + +import ( + "time" +) + +// AttemptStrategy represents a strategy for waiting for an action +// to complete successfully. This is an internal type used by the +// implementation of other goamz packages. +type AttemptStrategy struct { + Total time.Duration // total duration of attempt. + Delay time.Duration // interval between each try in the burst. + Min int // minimum number of retries; overrides Total +} + +type Attempt struct { + strategy AttemptStrategy + last time.Time + end time.Time + force bool + count int +} + +// Start begins a new sequence of attempts for the given strategy. +func (s AttemptStrategy) Start() *Attempt { + now := time.Now() + return &Attempt{ + strategy: s, + last: now, + end: now.Add(s.Total), + force: true, + } +} + +// Next waits until it is time to perform the next attempt or returns +// false if it is time to stop trying. +func (a *Attempt) Next() bool { + now := time.Now() + sleep := a.nextSleep(now) + if !a.force && !now.Add(sleep).Before(a.end) && a.strategy.Min <= a.count { + return false + } + a.force = false + if sleep > 0 && a.count > 0 { + time.Sleep(sleep) + now = time.Now() + } + a.count++ + a.last = now + return true +} + +func (a *Attempt) nextSleep(now time.Time) time.Duration { + sleep := a.strategy.Delay - now.Sub(a.last) + if sleep < 0 { + return 0 + } + return sleep +} + +// HasNext returns whether another attempt will be made if the current +// one fails. If it returns true, the following call to Next is +// guaranteed to return true. +func (a *Attempt) HasNext() bool { + if a.force || a.strategy.Min > a.count { + return true + } + now := time.Now() + if now.Add(a.nextSleep(now)).Before(a.end) { + a.force = true + return true + } + return false +} |