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use std::time::Duration;
cfg_async_or_blocking! {
use crate::Result;
}
#[derive(Clone, Debug)]
pub struct Retry {
max_retries: u32,
delay: Duration,
}
impl Default for Retry {
fn default() -> Self {
Self::new(20, Duration::from_millis(500))
}
}
impl Retry {
pub fn new(max_retries: u32, delay: Duration) -> Self {
Self { max_retries, delay }
}
pub fn none() -> Self {
Self::new(0, Duration::ZERO)
}
pub fn max_retries(&self) -> u32 {
self.max_retries
}
pub fn delay(&self) -> Duration {
self.delay
}
cfg_async_or_blocking! {
fn next_delay(&self, remaining_attempts: u32) -> Duration {
self.delay * self.max_retries.saturating_sub(remaining_attempts)
}
}
cfg_blocking! {
pub(crate) fn retry<T, F>(&self, f: F) -> Result<T>
where
F: Fn() -> Result<T>,
{
let mut remaining_attempts = self.max_retries();
loop {
match f() {
Ok(r) => return Ok(r),
Err(error) if error.is_retriable() && remaining_attempts > 0 => {
remaining_attempts = remaining_attempts.saturating_sub(1);
std::thread::sleep(self.next_delay(remaining_attempts));
}
Err(error) => return Err(error),
}
}
}
}
cfg_async! {
pub(crate) async fn retry_async<T, F, O>(&self, f: F) -> Result<T>
where
F: Fn() -> O,
O: std::future::Future<Output = Result<T>>,
{
let mut remaining_attempts = self.max_retries();
loop {
match f().await {
Ok(r) => return Ok(r),
Err(error) if error.is_retriable() && remaining_attempts > 0 => {
remaining_attempts = remaining_attempts.saturating_sub(1);
tokio::time::sleep(self.next_delay(remaining_attempts)).await;
}
Err(error) => return Err(error),
}
}
}
}
}