governor

Merge pull request #291 from boinkor-net/release/governor/0.10.4

release: governor v0.10.4

Another bug-fix release to repair the documentation build on docs.rs for good: The doc_auto_cfg feature was deprecated, this version switches to the feature doc_cfg.

Merge pull request #289 from boinkor-net/release/governor/0.10.3

release: governor v0.10.3

• Fixed a typo that prevented docs for 0.10.2 from building on docs.rs (#288). Thanks, @sp1ff!

Merge pull request #283 from boinkor-net/release/governor/0.10.2

release: governor v0.10.2

• Updated the hashbrown dependency to require version 0.16. Thanks, @cratelyn!

Merge pull request #278 from boinkor-net/release/governor/0.10.1

release: governor v0.10.1

• Updated code and tests to pass on nightly rust.

Merge pull request #267 from boinkor-net/release/governor/0.10.0

release: governor v0.10.0

Merge pull request #265 from boinkor-net/release/governor/0.9.0

release: governor v0.9.0

Merge pull request #261 from boinkor-net/release/governor/0.8.1

release: governor v0.8.1

Merge pull request #253 from boinkor-net/release/governor/0.8.0

release: governor v0.8.0

Changed

• Fixed the long-standing confusion of rate-limiting "tolerance" vs. "burst capacity": Tolerance is indicated with one cell less than burst capacity would be. The code treated the two as the same thing, leading to spurious single cells being allowed through when the clock advanced. (#107, #249). This confusion has finally been identified and fixed by @jonasmalacofilho in #251.

  This should not affect the public API, but any clients subject to rate-limiting may see a slightly fairer treatment.

Contributors

• @jonasmalacofilho

Merge pull request #248 from boinkor-net/release/governor/0.7.0

release: governor v0.7.0

This is a quick bug-fix release to address the semver incompatibility in 0.6.4. It is functionally identical to 0.6.4, with the exception of the dashmap version upgrade.

Changed

• Upgraded dashmap to 6.1.0.

Merge pull request #243 from boinkor-net/release/governor/0.6.4

release: governor v0.6.4

This release has been yanked because it violates Semantic Versioning ideals: The Clock argument type in functions like direct_with_clock changed, which breaks existing code.

Instead of 0.6.4, please use 0.7.0.

Added

• https://docs.rs/governor now lists the features required for feature-gated types and functions.

• A RateLimiter now has a clock method to retrieve the clock providing its timestamps. Added by @max-heller in #232.

Changed

• Clocks no longer need to be Clone. Changed by @max-heller in #232.

• governor now depends only on futures-util and futures-executor instead of the much larger futures crate. Fixed by @negezor in #239.

Changed

• Just another bug-fixed release process. This time, it should actually release out of github actions.

Changed

• The governor repo now lives in the boinkor-net github organization. No ownership has changed (@antifuchs still manages this org), but this makes it easier to securely manage the CI and release setup.

• The .per_second constructor for Quota now constructs a quota that ensures all rate-limiting calls succeed when given values in excess of 1 billion (previously, this would result in rate limiters that would incorrectly reject values). Reported in #203.

• QuantaUpkeepInstant now properly advances forward.

• no_std is now properly supported: Instead of parking-lot, governor now uses the spinning_top crate in no_std mode.

Contributors

• @rkd-msw
• @Serene-Arc
• @waynerobinson
• @mammothbane

Added

• Type aliases DefaultDirectRateLimiter and DefaultKeyedRateLimiter to cut down on type-typing of typical rate limiters in struct and function definitions. Requested in #85.

Changed

• The API for .check_n and .until_n (and their keyed counterpart) have changed to return a nested Result - the outer indicating whether the check could ever succeed and the inner one indicating the rate limiting result, if it could succeed.
• Updated the quanta dependency to 0.11.1. This change also adds a reference u64 instant to all instances of the QuantaUpkeepClock structure. All lower-resolution quanta timekeeping used by governor will now be relative to that reference instant.
• Some parts of the documentation for burst sizes has been rephrased to be less confusing.

Contributors

• @brprkr

Changed

• Fixed quota reporting for positive rate limiting decisions when StateInformationMiddleware is in use with a real clock. Reported in #157

Contributors

• @AaronErhardt

Changed

• Fixed a bug in StateSnapshot::remaining_burst_capacity: Now returns the correct number of cells after enough time has passed. Thanks to @holmesmr for reporting #102!

• Dropped a From<(&_ Gcra, Nanos)> impl for StateSnapshot.

Changed

• Upgraded dashmap back to 5.1.0.
• Upgraded parking_lot to 0.12.0.

Internal

• Migrated the governor code base to cargo workspaces.

Changed

• Downgraded dashmap to 4.0.2 as a remediation for RUSTSEC-2022-0002 via #104.

Contributors

• @kim

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 and issue #66 for details.

Changed

• Updated the Arc guide section to use Arc::clone() instead of limiter.clone().
• Updated the quanta dependency 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
• @izik1
• @ldm0

Added

• A little section to the guide explaining how to use keyed rate limiters.

Changed

Several dependencies' minimum versions were bumped, including a version bump of smallvec, a transitive dependency which could previously result in trees using governor pulling in a vulnerable smallvec version.

Contributors

• @AaronErhardt
• @FintanH

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 for the idea and pull request 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
• @korrat
• @lytefast

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
  • A keyed state store based on a mutex-locked HashMap.

• Support for different clock kinds:

  • Quanta (the default), a high-performance clock
  • Instant, 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
• @antifuchs

Initial release: A "direct" (a single rate-limiting state per structure) rate limiter that works in an async context, using atomic operations.