December 2021 Release Notes - Version 21.12.0

The year-end holiday season is upon us, so Happy New Year 🎩 🥂 and enjoy our December release! 🥳

Util

Breaking API Changes

• util-core: Activity.collect* and Var.collect* are now implemented in terms of known collection type scala.collection.Seq versus HKT CC[X] before. This allows for certain performance enhancements as well as makes it more aligned with the Future.collect APIs. caf528e2

Scrooge

No Changes

Finagle

Deprecations

• finagle-zipkin-core: c.t.f.zipkin.core.Sampler.DefaultSampleRate is deprecated in favor of c.t.f.zipkin.core.DefaultSampler.sampleRate. bd04e1c9

Bug Fixes

• finagle-zipkin-core: c.t.f.zipkin.core.Sampler would sample at 1/10,000 rate when configured with a lower (but non-zero) rate. It can now sample at rates as low as 1/16,777,216. 17cfb580

Runtime Behavior Changes

• finagle-zipkin-scribe: c.t.f.zipkin.thrift.ZipkinTracer uses c.t.f.zipkin.core.DefaultSampler.sampleRate as the default sample rate instead of deprecated c.t.f.zipkin.core.Sampler.DefaultSampleRate. This allows it to correctly observe user-configured overrides to the default sample rate. When a ZipkinTracer is constructed with default parameters and there are no user-configured overrides, the behavior is unchanged. bd04e1c9

Finatra

Changed

• inject-core: Move runAfterAll hook from c.t.inject.IntegrationTestMixin to c.t.inject.TestMixin fd108ada

Twitter Server

No Changes