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@@ -5,37 +5,9 @@ package retrier
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import (
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import (
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"context"
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"context"
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- "math/rand"
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- "sync"
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"time"
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"time"
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)
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)
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-// Retrier implements the "retriable" resiliency pattern, abstracting out the process of retrying a failed action
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-// a certain number of times with an optional back-off between each retry.
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-type Retrier struct {
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- backoff []time.Duration
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- class Classifier
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- jitter float64
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- rand *rand.Rand
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- randMu sync.Mutex
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-}
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-
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-// New constructs a Retrier with the given backoff pattern and classifier. The length of the backoff pattern
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-// indicates how many times an action will be retried, and the value at each index indicates the amount of time
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-// waited before each subsequent retry. The classifier is used to determine which errors should be retried and
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-// which should cause the retrier to fail fast. The DefaultClassifier is used if nil is passed.
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-func New(backoff []time.Duration, class Classifier) *Retrier {
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- if class == nil {
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- class = DefaultClassifier{}
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- }
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-
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- return &Retrier{
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- backoff: backoff,
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- class: class,
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- rand: rand.New(rand.NewSource(time.Now().UnixNano())),
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- }
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-}
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-
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// Run executes the given work function by executing RunCtx without context.Context.
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// Run executes the given work function by executing RunCtx without context.Context.
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func (r *Retrier) Run(work func() error) error {
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func (r *Retrier) Run(work func() error) error {
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return r.RunCtx(context.Background(), func(ctx context.Context) error {
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return r.RunCtx(context.Background(), func(ctx context.Context) error {
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@@ -80,20 +52,3 @@ func (r *Retrier) sleep(ctx context.Context, t <-chan time.Time) error {
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return ctx.Err()
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return ctx.Err()
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}
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}
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}
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}
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-
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-func (r *Retrier) calcSleep(i int) time.Duration {
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- // lock unsafe rand prng
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- r.randMu.Lock()
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- defer r.randMu.Unlock()
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- // take a random float in the range (-r.jitter, +r.jitter) and multiply it by the base amount
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- return r.backoff[i] + time.Duration(((r.rand.Float64()*2)-1)*r.jitter*float64(r.backoff[i]))
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-}
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-
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-// SetJitter sets the amount of jitter on each back-off to a factor between 0.0 and 1.0 (values outside this range
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-// are silently ignored). When a retry occurs, the back-off is adjusted by a random amount up to this value.
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-func (r *Retrier) SetJitter(jit float64) {
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- if jit < 0 || jit > 1 {
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- return
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- }
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- r.jitter = jit
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-}
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