# Changes for [`governor`](https://crates.io/crates/governor)
## [Unreleased] - ReleaseDate
## [[0.5.0](https://docs.rs/governor/0.5.0/governor/)] - 2022-09-19
### Changed
* Fixed a bug in `StateSnapshot::remaining_burst_capacity`: Now
returns the correct number of cells after enough time has
passed. Thanks to [@holmesmr](https://github.com/holmesmr) for
reporting [#102](https://github.com/antifuchs/governor/issues/102)!
* Dropped a `From<(&_ Gcra, Nanos)>` impl for `StateSnapshot`.
## [[0.4.2](https://docs.rs/governor/0.4.2/governor/)] - 2022-02-09
### Changed
* Upgraded `dashmap` back [to 5.1.0](https://github.com/antifuchs/governor/pull/110).
* Upgraded `parking_lot` [to 0.12.0](https://github.com/antifuchs/governor/pull/109).
## Internal
* Migrated the `governor` code base to [cargo
workspaces](https://doc.rust-lang.org/book/ch14-03-cargo-workspaces.html).
## [[0.4.1](https://docs.rs/governor/0.4.1/governor/)] - 2022-01-21
### Changed
* Downgraded `dashmap` to 4.0.2 as a remediation for
[RUSTSEC-2022-0002](https://rustsec.org/advisories/RUSTSEC-2022-0002)
via [#104](https://github.com/antifuchs/governor/pull/104).
### Contributors
* [@kim](https://github.com/kim)
## [[0.4.0](https://docs.rs/governor/0.4.0/governor/)] - 2021-12-28
### Added
* You can now alter&expand the information returned from a rate
limiter by attaching middleware to it using
`.with_middleware::<YourClass>()` at construction time.
This is an incompatible change, as the type signature of RateLimiter
gained an additional generic parameter. See the [pull
request](https://github.com/antifuchs/governor/pull/67) and
[issue #66](https://github.com/antifuchs/governor/issues/66) for
details.
### Changed
* Updated the [`Arc` guide section](https://docs.rs/governor/0.3.3/governor/_guide/index.html#wrapping-the-limiter-in-an-arc) to use `Arc::clone()` instead of `limiter.clone()`.
* Updated the [`quanta` dependency](https://crates.io/crates/quanta)
to 0.8.0, speeding up the quanta clock by a bit. This changes the
upkeep clock interface incompatibly: The quanta upkeep Builder
structure got renamed to `quanta::Upkeep`.
* The `nanos` module is now public, allowing other crates to implement
the `Clock` trait.
* When using the `std` feature, governor will no longer pull in the
`hashbrown` crate.
### Contributors
* [@bradfier](https://github.com/bradfier)
* [@izik1](https://github.com/izik1)
* [@ldm0](https://github.com/ldm0)
## [[0.3.2](https://docs.rs/governor/0.3.2/governor/)] - 2021-01-28
## [[0.3.1](https://docs.rs/governor/0.3.1/governor/)] - 2020-07-26
### Added
* A little section to the
[guide](https://docs.rs/governor/0.3.1/governor/_guide/index.html)
explaining how to use keyed rate limiters.
### Changed
Several dependencies' minimum versions were bumped, including a
version bump of
[`smallvec`](https://github.com/servo/rust-smallvec), a transitive
dependency which could previously result in trees using `governor`
pulling in a vulnerable smallvec version.
### Contributors
* [@AaronErhardt](https://github.com/AaronErhardt)
* [@FintanH](https://github.com/FintanH)
## [[0.3.0](https://docs.rs/governor/0.3.0/governor/)] - 2020-07-25
### Added
* The `ShrinkableKeyedStateStore` trait now has required `len` and
`is_empty` methods, which are also made available on any
`RateLimiter` that uses a shrinkable (Hashmap / Dashmap backed)
state store. Thanks to [@lytefast](https://github.com/lytefast) for
the idea and [pull request](https://github.com/antifuchs/ratelimit_meter/pull/38)
on `ratelimit_meter`!
### Changed
* The `MonotonicClock` and `SystemClock` struct definitions now are
proper "empty" structs. Any non-`Default` construction of these clocks
must now use `MonotonicClock` instead of `MonotonicClock()`.
* The `clock::ReasonablyRealtime` trait got simplified and no longer
has any required methods to implement, only one default method.
* Replaced the `spin` crate with `parking_lot` for `no_std` contexts.
### Contributors
* [@Restioson](https://github.com/Restioson)
* [@korrat](https://github.com/korrat)
* [@lytefast](https://github.com/lytefast)
## [[0.2.0](https://docs.rs/governor/0.2.0/governor/)] - 2020-03-01
### Added
* This changelog!
* New type `RateLimiter`, superseding the `DirectRateLimiter` type.
* Support for keyed rate limiting in `RateLimiter`, which allows users
to keep a distict rate limit state based on the value of a hashable
element.
* Support for different state stores:
* The direct in-memory state store
* A keyed state store based on [dashmap](https://crates.io/crates/dashmap)
* A keyed state store based on a mutex-locked [HashMap](https://doc.rust-lang.org/nightly/std/collections/struct.HashMap.html).
* Support for different clock kinds:
* [Quanta](https://crates.io/crates/quanta) (the default), a high-performance clock
* [Instant](https://doc.rust-lang.org/nightly/std/time/struct.Instant.html), the stdlib monotonic clock
* A fake releative clock, useful for tests or in non-std environments.
* `Quota` constructors now support a separate `.allow_burst` method
that specifies a maximum burst capacity that diverges from the
default.
* New constructor `Quota::with_period` allows specifying the exact
amount of time it takes to replenish a single element.
### Deprecated
* The `Quota::new` constructor has some very confusing modalities, and
should not be used as-is.
### Fixed
* An off-by-one error in `check_n`, causing calls with `n =
burst_size + 1` to return a "not yet" result instead of a "this will
never work" result.
### Contributors
* [@jean-airoldie](https://github.com/jean-airoldie)
* [@antifuchs](https://github.com/antifuchs)
## [0.1.2](https://docs.rs/governor/0.1.2/governor/) - 2019-11-17
Initial release: A "direct" (a single rate-limiting state per
structure) rate limiter that works in an async context, using atomic
operations.