Version 1.21.0

API

API Extensions

• WARNING: opentelemetry-extension-aws has been removed following its relocation to opentelemetry-java-contrib/aws-xray-propagator, which is published under coordinates io.opentelemetry.contrib:opentelemetry-aws-xray-propagator:{version}. We will push security patches to 1.20.x as needed. The latest opentelemetry-bom will point to the latest published version, currently 1.20.1. (#4945)
• Add toString implementation to various propagator components (#4996)

SDK

Logs

• Add toString implementation to various log SDK components (#4979)

Metrics

• Add histogram collection benchmark (#4912)
• Add ExponentialHistogramIndexerBenchmark (#4989)
• Stop extra copy of exponential histogram buckets (#5020)

Exporter

• Zipkin exporter serializes EventData attributes as JSON (#4934)
• Add support for EC mTLS keys (applies to OtlpHttp{Signal}Exporter, OtlpGrpc{Signal}Exporter, JaegerGrpcSpanExporter, JaegerRemoteSampler) (#4920)
• Add Configurable{Signal}ExporterProvider implementations for Logging{Signal}Exporters (#4950)
• Add ConfigurableSpanExporterProvider implementation for ZipkinSpanExporter (#4991)
• Add Configurable{Signal}ExporterProvider implementations for OtlpJsonLogging{Signal}Exporters (#4992)
• ZipkinSpanExporter populates remoteEndpoint (#4933)

SDK Extensions

• BREAKING: Remove support for otel.experimental.sdk.enabled from autoconfigure (#4973)
• De-singleton ZPageServer implementation (#4935)
• Add auto-configure support for logging-otlp exporters (#4879)
• Move DefaultConfigProperties to internal package in opentelemetry-sdk-extension-autoconfigure-spi (#5001)

Testing

• Make APIs for asserting attributes consistent (#4882)
• Attribute assertions error messages always contain the attr key (#5027)

Semantic Conventions

• Update semantic and resource attributes for spec v0.16.0 (#4938, #5033)

OpenTracing Shim

• Handle unsupported types when setting Attributes (#4939)
• Properly set the status based on the error tag (#4962)
• Handle io.opentracing.noop.NoopSpan correctly (#4968)
• Log invalid arguments rather than throwing exceptions. (#5012)
• Stop mapping semconv values from OpenTracing to OTel. (#5016)

🙇 Thank you

This release was possible thanks to the following contributors who shared their brilliant ideas and awesome pull requests:

@ben-roling
@breedx-splk
@carlosalberto
@giraone
@jack-berg
@jkwatson
@jonatan-ivanov
@knutwannheden
@lmonkiewicz
@mateuszrzeszutek
@mattspataro
@sno544
@sriraamas
@tmccombs
@trask
@yunchen-myob