Documentation
¶
Index ¶
- Constants
- func FullJitter[T ~int64 | ~int | ~int32 | ~float64 | ~float32](input T) T
- func GetBackoffForNextSchedule(cronSchedule string, scheduledTime time.Time, now time.Time) time.Duration
- func GetBackoffForNextScheduleNonNegative(cronSchedule string, scheduledTime time.Time, now time.Time) time.Duration
- func IgnoreErrors(errorsToExclude []error) func(error) bool
- func Jitter[T ~int64 | ~int | ~int32 | ~float64 | ~float32](input T, coefficient float64) T
- func ThrottleRetry(operation Operation, policy RetryPolicy, isRetryable IsRetryable) error
- func ThrottleRetryContext(ctx context.Context, operation OperationCtx, policy RetryPolicy, ...) error
- func ValidateSchedule(cronSchedule string) error
- type ExponentialRetryPolicy
- func (p *ExponentialRetryPolicy) ComputeNextDelay(elapsedTime time.Duration, numAttempts int) time.Duration
- func (p *ExponentialRetryPolicy) WithBackoffCoefficient(backoffCoefficient float64) *ExponentialRetryPolicy
- func (p *ExponentialRetryPolicy) WithExpirationInterval(expirationInterval time.Duration) *ExponentialRetryPolicy
- func (p *ExponentialRetryPolicy) WithInitialInterval(initialInterval time.Duration) *ExponentialRetryPolicy
- func (p *ExponentialRetryPolicy) WithMaximumAttempts(maximumAttempts int) *ExponentialRetryPolicy
- func (p *ExponentialRetryPolicy) WithMaximumInterval(maximumInterval time.Duration) *ExponentialRetryPolicy
- type IsRetryable
- type Operation
- type OperationCtx
- type Retrier
- type RetryPolicy
Examples ¶
Constants ¶
const NoBackoff = time.Duration(-1)
NoBackoff is used to represent backoff when no cron backoff is needed
const (
// NoInterval represents Maximim interval
NoInterval = 0
)
Variables ¶
This section is empty.
Functions ¶
func FullJitter ¶ added in v1.20.0
func FullJitter[T ~int64 | ~int | ~int32 | ~float64 | ~float32](input T) T
FullJitter return random number from 0 to input, inclusive, exclusive
func GetBackoffForNextSchedule ¶ added in v0.6.0
func GetBackoffForNextSchedule(cronSchedule string, scheduledTime time.Time, now time.Time) time.Duration
GetBackoffForNextSchedule calculates the backoff time for the next run given a cronSchedule, current scheduled time, and now.
func GetBackoffForNextScheduleNonNegative ¶ added in v0.28.0
func GetBackoffForNextScheduleNonNegative(cronSchedule string, scheduledTime time.Time, now time.Time) time.Duration
GetBackoffForNextScheduleNonNegative calculates the backoff time and ensures a non-negative duration.
func IgnoreErrors ¶
func IgnoreErrors(errorsToExclude []error) func(error) bool
IgnoreErrors can be used as IsRetryable handler for Retry function to exclude certain errors from the retry list
func Jitter ¶ added in v0.3.14
func Jitter[T ~int64 | ~int | ~int32 | ~float64 | ~float32](input T, coefficient float64) T
Jitter return random number from (1-coefficient)*input to (1+coefficient)*input, inclusive, exclusive
func ThrottleRetry ¶ added in v1.17.1
func ThrottleRetry(operation Operation, policy RetryPolicy, isRetryable IsRetryable) error
ThrottleRetry is a resource aware version of Retry. Resource exhausted error will be retried using a different throttle retry policy, instead of the specified one.
func ThrottleRetryContext ¶ added in v1.17.1
func ThrottleRetryContext(
ctx context.Context,
operation OperationCtx,
policy RetryPolicy,
isRetryable IsRetryable,
) error
ThrottleRetryContext is a context and resource aware version of Retry. Context timeout/cancellation errors are never retried, regardless of IsRetryable. Resource exhausted error will be retried using a different throttle retry policy, instead of the specified one. TODO: allow customizing throttle retry policy and what kind of error are categorized as throttle error.
func ValidateSchedule ¶ added in v0.6.0
func ValidateSchedule(cronSchedule string) error
ValidateSchedule validates a cron schedule spec
Types ¶
type ExponentialRetryPolicy ¶
type ExponentialRetryPolicy struct {
// contains filtered or unexported fields
}
ExponentialRetryPolicy provides the implementation for retry policy using a coefficient to compute the next delay. Formula used to compute the next delay is:
min(initialInterval * pow(backoffCoefficient, currentAttempt), maximumInterval)
func NewExponentialRetryPolicy ¶
func NewExponentialRetryPolicy(initialInterval time.Duration) *ExponentialRetryPolicy
NewExponentialRetryPolicy returns an instance of ExponentialRetryPolicy using the provided initialInterval
func (*ExponentialRetryPolicy) ComputeNextDelay ¶
func (p *ExponentialRetryPolicy) ComputeNextDelay(elapsedTime time.Duration, numAttempts int) time.Duration
ComputeNextDelay returns the next delay interval. This is used by Retrier to delay calling the operation again
func (*ExponentialRetryPolicy) WithBackoffCoefficient ¶ added in v1.17.3
func (p *ExponentialRetryPolicy) WithBackoffCoefficient(backoffCoefficient float64) *ExponentialRetryPolicy
WithBackoffCoefficient sets the coefficient used by ExponentialRetryPolicy to compute next delay for each retry All retries are computed using the following formula: initialInterval * math.Pow(backoffCoefficient, currentAttempt)
func (*ExponentialRetryPolicy) WithExpirationInterval ¶ added in v1.17.3
func (p *ExponentialRetryPolicy) WithExpirationInterval(expirationInterval time.Duration) *ExponentialRetryPolicy
WithExpirationInterval sets the absolute expiration interval for all retries
func (*ExponentialRetryPolicy) WithInitialInterval ¶ added in v1.17.3
func (p *ExponentialRetryPolicy) WithInitialInterval(initialInterval time.Duration) *ExponentialRetryPolicy
WithInitialInterval sets the initial interval used by ExponentialRetryPolicy for the very first retry All later retries are computed using the following formula: initialInterval * math.Pow(backoffCoefficient, currentAttempt)
func (*ExponentialRetryPolicy) WithMaximumAttempts ¶ added in v1.17.3
func (p *ExponentialRetryPolicy) WithMaximumAttempts(maximumAttempts int) *ExponentialRetryPolicy
WithMaximumAttempts sets the maximum number of retry attempts
func (*ExponentialRetryPolicy) WithMaximumInterval ¶ added in v1.17.3
func (p *ExponentialRetryPolicy) WithMaximumInterval(maximumInterval time.Duration) *ExponentialRetryPolicy
WithMaximumInterval sets the maximum interval for each retry. This does *not* cause the policy to stop retrying when the interval between retries reaches the supplied duration. That is what WithExpirationInterval does. Instead, this prevents the interval from exceeding maximumInterval.
Example ¶
ExampleExponentialRetryPolicy_WithMaximumInterval demonstrates example delays with a backoff coefficient of 2 and a maximum interval of 10 seconds. Keep in mind that there is a random jitter in these times, so they are not exactly what you'd expect.
Output:
Attempt | Delay| Capped Delay
0 | 0.0s| 0.0s
1 | 0.8s| 0.9s
2 | 1.7s| 1.6s
3 | 3.3s| 3.2s
4 | 7.2s| 7.2s
5 | 15.1s| 9.6s
6 | 26.2s| 8.8s
7 | 62.8s| 9.4s
8 | 112.8s| 9.5s
9 | 219.7s| 8.3s
type IsRetryable ¶
type IsRetryable func(error) bool
IsRetryable handler can be used to exclude certain errors during retry
type OperationCtx ¶ added in v1.12.1
type OperationCtx func(context.Context) error
OperationCtx plays the same role as Operation but for context-aware retryable functions.
type Retrier ¶
type Retrier interface {
NextBackOff() time.Duration
Reset()
}
Retrier manages the state of retry operation
func NewRetrier ¶
func NewRetrier(policy RetryPolicy, timeSource clock.TimeSource) Retrier
NewRetrier is used for creating a new instance of Retrier
type RetryPolicy ¶
type RetryPolicy interface {
ComputeNextDelay(elapsedTime time.Duration, numAttempts int) time.Duration
}
RetryPolicy is the API which needs to be implemented by various retry policy implementations
var (
// DisabledRetryPolicy is a retry policy that never retries
DisabledRetryPolicy RetryPolicy = &disabledRetryPolicyImpl{}
)
Source Files