Struct Budget

pub struct Budget { /* private fields */ }

Represents a “budget” for retrying requests.

This is useful for limiting the amount of retries a service can perform over a period of time, or per a certain number of requests attempted.

Implementations

impl Budget

pub fn new(ttl: Duration, min_per_sec: u32, retry_percent: f32) -> Self

Create a Budget that allows for a certain percent of the total requests to be retried.

• The ttl is the duration of how long a single deposit should be considered. Must be between 1 and 60 seconds.

• The min_per_sec is the minimum rate of retries allowed to accomodate clients that have just started issuing requests, or clients that do not issue many requests per window.

• The retry_percent is the percentage of calls to deposit that can be retried. This is in addition to any retries allowed for via min_per_sec. Must be between 0 and 1000.

  As an example, if 0.1 is used, then for every 10 calls to deposit, 1 retry will be allowed. If 2.0 is used, then every deposit allows for 2 retries.

pub fn deposit(&self)

Store a “deposit” in the budget, which will be used to permit future withdrawals.

pub fn withdraw(&self) -> Result<(), Overdrawn>

Check whether there is enough “balance” in the budget to issue a new retry.

If there is not enough, an Err(Overdrawn) is returned.

Trait Implementations

impl Debug for Budget

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

Formats the value using the given formatter.

impl Default for Budget

fn default() -> Budget

Returns the “default value” for a type.