Struct RetryPolicy 

pub struct RetryPolicy { /* private fields */ }

Decides how often a failed delivery is retried and how long its subscription waits between attempts. A delivery keeps its subscription’s concurrency slot while it waits, so a subscription handling one message at a time retries it before moving on to the next. Delays that would overflow saturate at Duration::MAX, use with_max_delay to cap them.

Example

use std::time::Duration;
use topmesys::RetryPolicy;

let policy = RetryPolicy::exponential(4, Duration::from_millis(100))
    .with_max_delay(Duration::from_millis(500));

assert_eq!(policy.delay(1), Duration::from_millis(100));
assert_eq!(policy.delay(3), Duration::from_millis(400));
assert_eq!(policy.delay(4), Duration::from_millis(500));

Implementations

impl RetryPolicy

pub fn new(retries: u32, backoff: Backoff) -> Self

Retries a failed delivery up to retries times, waiting according to backoff.

pub fn none() -> Self

Never retries: a failed delivery is dead-lettered right away.

pub fn fixed(retries: u32, delay: Duration) -> Self

pub fn linear(retries: u32, initial: Duration, increment: Duration) -> Self

pub fn exponential(retries: u32, initial: Duration) -> Self

Doubles the delay with every retry, starting at initial.

pub fn with_max_delay(self, max_delay: Duration) -> Self

Caps every delay at max_delay.

pub fn with_jitter(self) -> Self

Randomises every delay to between half and all of its computed value, so deliveries that failed together don’t retry at the same moment.

pub fn retries(&self) -> u32

pub fn delay(&self, retry: u32) -> Duration

The delay before the given retry, counting from 1. Jitter is not applied.

Trait Implementations

impl Clone for RetryPolicy

fn clone(&self) -> RetryPolicy

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for RetryPolicy

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for RetryPolicy

fn default() -> Self

Returns the “default value” for a type.

impl PartialEq for RetryPolicy

fn eq(&self, other: &RetryPolicy) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for RetryPolicy