Version 1.20.1

This is a patch release on the previous 1.20.0 release, fixing the issue(s) below.

Bugfixes

• Fix bug in ComponentRegistry that produces ConcurrentModificationException when reading metrics at the same time as obtaining a meter. (#4951)

Version 1.20.0

API

• Fix bug in W3CBaggagePropagator that caused + characters to be decoded as whitespace . (#4898)

API Extensions

• DEPRECATION: the opentelemetry-extension-aws module containing various AwsXrayPropagator implementations has been deprecated for removal in next major version. A copy of the code will instead be maintained in opentelemetry-java-contrib/aws-xray-propagator and published under coordinates io.opentelemetry.contrib:opentelemetry-aws-xray-propagator:{version}. (#4862)

SDK

Traces

• Add graal hints for shaded dependencies, allowing JcTools queue to be used in graal environment. (#4832)
• Sampler#getDescription() implementations are now locale independent. (#4877)
• Allow SDK to run in environments prohibiting use of sun.misc.Unsafe. (#4902)

Metrics

• Add toString to AbstractInstrument. (#4833)
• Add zero bucket boundary to default explicit bucket histogram aggregation. (#4819)

Logs

• Optimize log hot path, reducing allocations significantly. (#4913)
• BREAKING: Add Context argument to LogRecordProcessor#onEmit. (#4889)

Exporter

• OtlpLogging{Signal}Exporters encode enums as numbers. (#4783)
• Add User-Agent header of OTel OTLP Exporter Java/{version} to OTLP export requests. (#4784)

SDK Extensions

• WARNING: opentelemetry-sdk-extension-aws has been removed following its relocation to opentelemetry-java-contrib/instrumentation-aws-xray, which is published under coordinates io.opentelemetry.contrib:opentelemetry-aws-resources:{version}. We will push security patches to 1.19.x as needed. The latest opentelemetry-bom will point to the latest published version, currently 1.19.0. (#4830)
• WARNING: opentelemetry-sdk-extension-resources has been removed following its relocation to opentelemetry-java-instrumentation/instrumentation/resources/library, which is published under coordinates io.opentelemetry.instrumentation:opentelemetry-resources:{version}. We will push security patches to 1.19.x as needed. The latest opentelemetry-bom will point to the latest published version, currently 1.19.0. (#4828)
• Add autoconfigure support for BatchLogRecordProcessor. (#4811)
• Autoconfigure performs percent decoding on otel.resource.attributes values. (#4653)
• Unify compression configuration for exporters including (#4775): * Fix handling of none in OTLP exporters. * Add JaegerGrpcSpanExporterBuilder#setCompression(String). * Add ZipkinSpanExporterBuilder#setCompression(String).

Semantic Conventions

• Add migration notes to deprecated attributes (#4840)

OpenTracing Shim

• Use opentracing-shim as instrumentation scope name. (#4890)
• Add full support for multiple parents. (#4916)

🙇 Thank you

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

@amouhadi
@bogdandrutu
@breedx-splk
@carlosalberto
@codeboten
@Donnerbart
@fniephaus
@jack-berg
@jkwatson
@jsuereth
@kubawach
@lgfa29
@lmonkiewicz
@lukiano
@marcingrzejszczak
@mateuszrzeszutek
@mkorzeniewski
@reyang
@rrva
@sdeleuze
@trask

Version 1.19.0

This release contains a large number of changes to the log signal following a series of significant changes to the log specification. The changes include renaming key classes like LogExporter to LogRecordExporter, and LogProcessor to LogRecordProcessor, and LogEmitter to Logger, and more. Additionally, a log API component has been added for emitting events and for writing log appenders. Note, the log API is not a substitute for traditional log frameworks like Log4j, JUL, SLF4J, or Logback. While the event portion of the API is intended for instrumentation authors and end users, the API for emitting LogRecords is not. See LoggerProvider and Logger javadoc for more details.

General

• Add opentelemetry-bom as a dependency to opentelemetry-bom-alpha, ensuring synchronization between alpha and stable artifact versions.

API

API Extensions

• WARNING: opentelemetry-extension-annotations has been removed following its relocation to opentelemetry-java-instrumentation/instrumentation-annotations, which is published under coordinates io.opentelemetry.instrumentation:opentelemetry-instrumentation-annotations:{version}. We will push security patches to 1.18.x as needed. The latest opentelemetry-bom will point to the latest published version, currently 1.18.0.

Logs

• Introduce log API for emitting events and writing log appenders. The artifact is available at coordinates io.opentelemetry:opentelemetry-api-logs:1.19.0-alpha.

SDK

Metrics

• Change exponential histogram bucket boundaries to be lower exclusive / upper inclusive, instead of lower inclusive / upper exclusive.

Logs

• BREAKING: Rename SdkLogEmitterProvider to SdkLoggerProvider. OpenTelemetrySdkBuilder#setLogEmitterProvider has changed to OpenTelemetrySdkBuilder#setLoggerProvider. OpenTelemetrySdk#getSdkLogEmitterProvider has changed to OpenTelemetrySdk#getSdkLoggerProvider. AutoConfigurationCustomizer#addLogEmitterProviderCustomizer has changed to AutoConfigurationCustomizer#addLoggerProviderCustomizer.
• BREAKING: Rename LogEmitter to Logger.
• BREAKING: Rename LogExporter to LogRecordExporter. SystemOutLogExporter has changed to SystemOutLogRecordExporter. OtlpJsonLoggingLogExporter has changed to OtlpJsonLoggingLogRecordExporter. OtlpHttpLogExporter has changed to OtlpHttpLogRecordExporter. OtlpGrpcLogExporter has changed to OtlpGrpcLogRecordExporter. InMemoryLogExporter has changed to InMemoryLogRecordExporter. ConfigurableLogExporterProviderhas changed toConfigurableLogRecordExporterProvider`.
• BREAKING: Rename LogData to LogRecordData. TestLogData has changed to TestLogRecordData.
• BREAKING: Rename LogProcessor to LogRecordProcessor. BatchLogProcessor has changed to BatchLogRecordProcessor. SimpleLogProcessor has changed to SimpleLogRecordProcessor.

Exporter

• OTLP log record exporters now include dropped_attributes_count.

SDK Extensions

• Autoconfigure now supports an option to disable the SDK. If otel.sdk.disabled=true, AutoConfiguredOpenTelemetrySdk#getOpenTelemetrySdk() returns a minimal (but not noop) OpenTelemetrySdk with noop tracing, metric and logging providers. The same minimal instance is set to GlobalOpenTelemetry. The now deprecated property otel.experimental.sdk.enabled will continue to work in the same way during a transition period.
• Fix ProcessResource directory separator to use / or \ instead of : or ;.
• DEPRECATION: the opentelemetry-sdk-extension-resource module containing various ResourceProvider implementations has been deprecated for removal in next major version. A copy of the code will instead be maintained in opentelemetry-java-instrumentation/instrumentation/resources/library and published under coordinates io.opentelemetry.instrumentation:opentelemetry-resources:{version}.
• DEPRECATION: the opentelemetry-sdk-extension-aws module containing AWS ResourceProvider implementations has been deprecated for removal in next major version. A copy of the code will instead be maintained in opentelemetry-java-contrib/aws-resources and published under coordinates io.opentelemetry.contrib:opentelemetry-aws-resources:{version}.

OpenTracing Shim

• Fully support Baggage-only propagation.

Semantic conventions

• The semantic conventions have been updated to 1.13.0.

🙇 Thank you

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

@anuraaga
@breedx-splk
@brunobat
@carlosalberto
@jack-berg
@jamesmoessis
@jkwatson
@jmacd
@joshua-bell-sonrai
@jsuereth
@mateuszrzeszutek
@rapphil
@SampathKumarAmex
@trask

Version 1.18.0

SDK

• Added scope attributes to InstrumentationScopeInfo accessible via InstrumentationScopeInfo#getAttributes(). Will add the ability to specify scope attributes in Meter, Tracer, and Logger in a future version.
• DEPRECATION: The InstrumentationScopeInfo#create(String, String, String) method has been deprecated in favor of InstrumentationScopeInfo#builer(String).setVersion(String).setSchemaUrl(String).build().
• Optimize Resource#merge(Resource) by returning early if the other resource is empty.

Logs

• Fix module name of opentelemetry-sdk-logs by changing from io.opentelemetry.sdk.extension.logging to io.opentelemetry.sdk.logs.

Testing

• Add methods to assert attributes do not contain keys via AttributeAssert#doesNotContainKey().

Exporter

• Added ability to specify local IP address in ZipkinSpanExporter via ZipkinSpanExporterBuilder#setLocalIpAddressSupplier(Supplier<InetAddress>).
• Upgrade to OTLP protobuf version 0.19.0.
• OTLP exporters now serialize InstrumentationScopeInfo#getAttributes().
• Stop publishing opentelemetry-exporter-jaeger-proto. The opentelemetry-bom will include a constraint on the last published version 1.17.0. If security issues are discovered, patches will be published to 1.17.x.

SDK Extensions

• BREAKING: opentelemetry-sdk-extension-metric-incubator, opentelemetry-sdk-extension-tracing-incubator, and opentelemetry-sdk-extension-zpages merged into opentelemetry-sdk-extension-incubator.
• BREAKING: Move opentelemetry-sdk-extension-jfr-events to opentelemetry-java-contrib/jfr-events. It will now be published under the coordinates io.opentelemetry.contrib:opentelemetry-jfr-events:{version}.
• BREAKING: Move opentelemetry-extension-noop-api to opentelemetry-java-contrib/noop-api. It will now be published under the coordinates io.opentelemetry.contrib:opentelemetry-noop-api:{version}.
• Improve ECS resource detection to include aws.ecs.container.arn, container.image.name, container.image.tag, aws.ecs.container.image.id, aws.log.group.arns, aws.log.group.names, aws.log.steam.names, aws.ecs.task.arn, aws.ecs.task.family, and aws.ecs.task.revision.
• Fix resource container.id detection when using k8s with containerd v1.5.0+.
• Add experimental ConditionalResourceProvider SPI, for conditionally applying resource providers based on current config and resource.

Micrometer shim

• BREAKING: Move opentelemetry-micrometer1-shim to opentelemetry-java-instrumentation/instrumentation/micrometer/micrometer-1.5/library. It will now be published under the coordinates io.opentelemetry.instrumentation:opentelemetry-micrometer-1.5:{version}.

🙇 Thank you

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

@anuraaga
@bogdandrutu
@breedx-splk
@felixscheinost
@jack-berg
@jj22ee
@jkwatson
@kubawach
@mateuszrzeszutek
@mmanciop
@SampathKumarAmex
@trask
@willarmiros
@wzy531a

Version 1.17.0

API

API Extensions

• DEPRECATION: the opentelemetry-extension-annotations module containing @WithSpan and @SpanAttribute annotations has been deprecated for removal in next major version. A copy of the code will instead be maintained in opentelemetry-java-instrumentation/instrumentation-annotations and published under coordinates io.opentelemetry.instrumentation:opentelemetry-instrumentation-annotations:{version}.

SDK

Traces

• Add default implementation for SpanData#getInstrumentationScopeInfo() and ReadableSpan#getInstrumentationScopeInfo(). This fixes a previous mistake where those interfaces were extended without default implementation, a breaking change for source compatibility. Stricter checks have been added to ensure this mistake is not repeated.

Logs

• BREAKING: delete LogDataBuilder. A similar implementation of LogData called TestLogData has been added to opentelemetry-sdk-logs-testing.
• BREAKING: rename LogProcessor#emit(LogData) to LogProcessor#onEmit(ReadWriteLogRecord). The argument change from LogData to ReadWriteLogRecord allows implementations to mutate logs. To obtain LogData, call ReadWriteLogRecord#toLogData().
• Optimize SdkLogEmitterProvider to return noop LogEmitter when no LogProcessors are registered.

Exporter

• Split out shared and internal exporter classes from opentelemetry-exporter-otlp-common to opentelemetry-exporter-common.
• Add experimental support for OTLP header based authentication. To use, add a dependency on opentelemetry-exporter-common and call io.opentelemetry.exporter.internal.auth.Authenticator#setAuthenticatorOnDelegate(OtlpHttp{Signal}Builder, Authenticator).
• Add ability to collect export metrics on ZipkinSpanExporter via ZipkinSpanExporter#setMeterProvider(MeterProvider).
• Minor optimization to OkHttp based exporters to cache endpoint URLs. Applies to OtlpHttp{Signal}Exporter, OtlpGrpc{Signal}Exporter, and more.
• Fix diagnostic log message in OtlpGrpc{Signal}Exporter to include correct environment variables.

SDK Extensions

• Extend View file based configuration with support for specifying explicit bucket histogram bucket boundaries and exponential bucket counts.
• Extend autoconfigure SPI AutoConfigurationCustomizerProvider and ResourceProvider with option to specify ordering.
• Add autoconfigure SPI with ConfigurableLogExporterProvider, allowing custom named log exporters to be provided and selected via autoconfigure.
• Extend autoconfigure SPI with AutoConfigurationCustomizer#addPropertiesCustomizer, providing the ability examine current configuration properties and add / overwrite properties.

🙇 Thank you

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

@anuraaga
@bogdandrutu
@breedx-splk
@chalin
@DaveCTurner
@deejgregor
@Donnerbart
@GrahamLea
@iRevive
@jack-berg
@JavaPerformance
@jkwatson
@lmolkova
@mateuszrzeszutek
@sfriberg
@trask
@trivikr

Version 1.16.0

API

• Fix bug ImmutableKeyValuePairs implementation that causes ArrayIndexOutOfBoundsException to be thrown under certain conditions.

SDK

Traces

• Optimize BatchSpanProcessor using JcTools.

Metrics

• Tighten up exponential histogram implementation for alignment with specification: Default to 160 positive and negative buckets. Remove ability to configure starting scale. Minimum number of buckets is one instead of zero.
• Allow MetricExporter and MetricReader to influence default aggregation. The default aggregation is used when no registered views match an instrument.

Exporter

• Fix handling of client keys in PEM format.
• For OTLP exporters, change behavior to use OkHttpGrpcExporter (OkHttp implementation that doesn't use any gRPC dependencies) unless OtlpGrpc{Signal}Builder#setChannel(ManagedChannel) is called by user. Previously, OkHttpGrpcExporter was used if no gRPC implementation was found on classpath.
• Add support to configure default aggregation on OTLP metric exporters via Otlp{Protocol}MetricExporterBuilder#setDefaultAggregationSelector(DefaultAggregationSelector).

Testing

• Add span status assertions.

SDK Extensions

• Autoconfigure properly handles non-string system properties.
• Autoconfigure normalizes hyphens - to periods . when accessing ConfigProperties.

OpenTracing Shim

• Add support for span wrappers.
• Store OpenTracing SpanContext in OpenTracing Span wrapper.
• Use Baggage of active span.

🙇 Thank you

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

@aaron-ai
@anuraaga
@breedx-splk
@carlosalberto
@codeboten
@cuichenli
@fax4ever
@HaloFour
@jack-berg
@jkwatson
@jsuereth
@mateuszrzeszutek
@mohitmahi
@pavolloffay
@pureklkl
@trask
@xiangtianyu
@zeitlinger

Version 1.15.0

API

• Add batch callback API, allowing a single callback to record measurements to multiple metric instruments.

SDK

Metrics

• SdkMeterProvider#toString() now returns a useful string describing configuration.
• Fix bug preventing proper function of Metrics SDK when multiple readers are present (#4436).
• Fix reporting intervals for metrics for delta readers (#4400).

Exporter

• BREAKING: merge all stable OTLP exporters into opentelemetry-exporter-otlp. opentelemetry-exporter-otlp-trace, opentelemetry-exporter-otlp-metrics, opentelemetry-exporter-otlp-http-trace, and opentelemetry-exporter-otlp-http-metrics are no longer published and their contents have been merged into a single artifact.
• BREAKING: merge log OTLP exporters into opentelemetry-exporter-otlp-logs. opentelemetry-exporter-otlp-http-logs is no longer published and its contents have been merged into a single artifact.
• Upgrade to OTLP protobuf version 0.18.0.
• RetryInterceptor retries on SocketTimeoutException with no message.
• Added JaegerGrpcSpanExporterBuilder#setMeterProvider(), enabling support of experimental jaeger span export metrics.
• DEPRECATION: the opentelemetry-exporter-jaeger-proto module containing jaeger proto definitions and corresponding generated classes is deprecated for removal in next major version.
• OTLP gRPC exporters support overriding :authority via OtlpGrpc*ExporterBuilder#addHeader("host", "my-authority-override").

SDK Extensions

• BREAKING: Move ConfigureableMetricExporterProvider from opentelemetry-sdk-extension-autoconfigure to stable opentelemetry-sdk-extension-autoconfigure-spi.
• Autoconfigure now supports multiple values for otel.metrics.exporter.
• Autoconfigure now supports general attribute limits, applicable to span attributes, span event attributes, span link attributes, and log attributes.
• Autoconfigure now supports an experimental option to disable the SDK. If otel.experimental.sdk.enabled=true, AutoConfiguredOpenTelemetrySdk#getOpenTelemetrySdk() returns a minimal (but not noop) OpenTelemetrySdk. The same minimal instance is set to GlobalOpenTelemetry.
• New "get or default" methods have been added to ConfigProperties. E.g. ConfigProperties#getString("otel.metrics.exporter", "otlp") fetches the value for the property otel.metrics.exporter and returns otlp if it is not set.
• Fix bug in ContainerResource provider that caused it to throw an exception in some instances when containerd is used.

Micrometer shim

• Cache descriptions such that metrics with the same name use the first seen description.

🙇 Thank you

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

@anuraaga
@breedx-splk
@chenjazz
@cyrille-leclerc
@donce
@Donnerbart
@evantorrie
@jack-berg
@jkwatson
@jonahaapala
@jsuereth
@kubawach
@laurit
@marcalff
@mateuszrzeszutek
@nicklocaso
@Oberon00
@pkgonan
@rupinder10
@trask
@wallezhang

Version v1.14.0

The metrics SDK is stable! New stable artifacts include:

• io.opentelemetry:opentelemetry-sdk-metrics (also now included in io.opentelemetry:opentelemetry-sdk)
• io.opentelemetry:opentelemetry-exporter-otlp-metrics (also now included in io.opentelemetry:opentelemetry-exporter-otlp)
• io.opentelemetry:opentelemetry-exporter-otlp-http-metrics
• Metrics testing components have been moved from io.opentelemetry:opentelemetry-sdk-metrics-testing to the stable io.opentelemetry:opentelemetry-sdk-testing.

While the API of the metrics SDK is now stable, there are a couple of known issues that will be addressed in the next release:

• The start time is incorrect for delta metrics when the first recording for a set of attributes occurs after the first collections (#4400).
• Registering multiple readers results in incorrect metrics (#4436).

SDK

Traces

• Fix bug where non-runtime exception breaks BatchSpanProcessor.
• Fix bug preventing attribute limits from applying to exception events.

Logs

• BREAKING: Drop deprecated methods referencing InstrumentationLibraryInfo from Log SDK.

Metrics

• Instrument name is validated. If invalid, a warning is logged and a noop instrument is returned.
• Default unit is empty instead of 1. If an invalid unit is set, a warning is logged and empty is used.
• Ensure symmetry between type of PointData and their type of exemplars (double or long).
• BREAKING: Rename MetricReader#flush() to MetricReader#forceFlush().
• Introduce AggregationTemporalitySelector interface for selecting aggregation temporality based on instrument. MetricReader and MetricExporter extend AggregationTemporalitySelector.

SDK Extensions

• BREAKING: Remove deprecated option to specify temporality with otel.exporter.otlp.metrics.temporality. Use otel.exporter.otlp.metrics.temporality.preference instead.
• Log warning when AwsXrayPropagator can't identify parent span id.
• Fix jaeger remote sampling bug preventing correct parsing of 0-probability sampling strategies.

Exporter

• Fix prometheus exporter formatting bug when there are no attributes.
• Ensure prometheus metrics with the same name are serialized as a group.
• BREAKING: OtlpHttpMetricExporterBuilder and OtlpGrpcMetricExporterBuilder configure aggregation temporality via #setAggregationTemporalitySelector(AggregationTemporalitySelector).

Testing

• BREAKING: Metrics testing components added to stable io.opentelemetry:opentelemetry-sdk-testing module, including InMemoryMetricReader, InMemoryMetricExporter, and MetricAssertions.assertThat(MetricData) has been moved to OpenTelemetryAssertions.assertThat(MetricData).
• BREAKING: The patterns for metrics assertions have been adjusted to better align with assertj conventions. See #4444 for examples demonstrating the change in assertion patterns.
• BREAKING: Metric assertion class names have been simplified.
• Add TraceAssert.hasSpansSatisfyingExactlyInAnyOrder(..) methods.

Micrometer shim

• Instrumentation scope name changed to io.opentelemetry.micrometer1shim.

Project tooling

• Many improvements to the build and release workflows. Big thanks to @trask for driving standardization across opentelemetry-java, opentelemetry-java-instrumentation, and opentelemetry-java-contrib!

🙇 Thank you

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

@anuraaga
@arminru
@cbos
@chrismgrayftsinc
@gfelbing
@jack-berg
@jkwatson
@jsuereth
@kubawach
@laurit
@mateuszrzeszutek
@middlewareman
@OliverO2
@trask
@wallezhang
@ZQiannnn

Version v1.13.0

Although we originally intended 1.13.0 to be the first stable release of the metrics SDK, we've postponed it out of caution due to a large number of changes in both the metrics SDK specification and the java implementation. This release should be considered a release candidate for the metrics SDK. There are several notable changes mentioned in the Metrics section. Additionally, please note that the Auto-configuration module now enables metric export by default via OTLP, i.e. by default otel.metrics.exporter is set to otlp instead of none.

API

• Fix TraceStateBuilder reuse bug.

SDK

• InstrumentationScopeInfo replaces InstrumentationLibraryInfo. Methods returning InstrumentationLibraryInfo are deprecated.
• Add ResourceBuilder#removeIf(Predicate) method for symmetry with AttributesBuilder.

Traces

• Span events that record exceptions are instances of ExceptionEventData.

Metrics

• BREAKING: Remove MetricReader factory pattern:
  • MetricReader instances, rather than MetricReaderFacotry, are registered with SdkMeterProviderBuilder. For example: SdkMeterProvider.builder().registerMetricReader(PeriodicMetricReader.builder(exporter).build()).
  • MetricReader does not support custom implementations. Built-in readers include: PeriodicMetricReader, PrometheusHttpServer, and for testing, InMemoryMetricReader.
• BREAKING: Several breaking changes metrics to the Data classes:
  • MetriaData returns InstrumentationScopeInfo instead of InstrumentationLibraryInfo.
  • MetricData factories classes have been moved internal.
  • Exemplar data classes have been migrated to interfaces, and deprecated methods have been removed.
  • PointData classes have been migrated to interfaces.
  • ValueAtPercentile has been converted to ValueAtQuantile to reflect specification.
  • Drop HistogramPointData utility methods for finding bucket bounds.
• BREAKING: Move InstrumentType and InstrumentValueType to io.opentelemetry.sdk.metrics package.
• BREAKING: Several breaking changes to the InstrumentSelector / View APIs:
  • InstrumentSelector / View and corresponding builders have been moved to io.opentelemetry.sdk.metrics package.
  • InstrumentSelector meter selection criteria has been inlined and MeterSelector has been removed.
  • InstrumentSelector criteria has been reduced to reflect specification. All fields are exact match, except instrument name which accepts wildcard * and ? matches.
  • If InstrumentSelectorBuilder#build() is called without any selection criteria, an exception will be thrown.
  • View baggage appending attribute processor has been removed. Available for experimental use via SdkMeterProviderUtil#appendFilteredBaggageAttributes.
  • Concept of AttributeProcessor has been moved internal.
  • If a View configures an aggregation that is not compatible with the instrument type of a selected instrument, a warning is logged and the View is ignored.
• BREAKING: Remove deprecated Aggregation#histogram(). Use Aggregation#explicitBucketHistogram() instead.
• Relax behavior around conflicting instruments. If you register two instruments with the same name but conflicting description, unit, type, or value type, both will be exported and a warning will be logged indicating the metric identity conflict. Previously, the second registered would have produced a noop instrument. Likewise, if two views are registered that produce instruments with conflicting names, or if an instrument conflicts with a registered view's name, both will be exported and a warning will be logged indicating the view conflict.
• BREAKING: Exemplars have been moved to internal. By default, exemplars are enabled with with_sampled_trace filter. This can be adjusted via experimental APIs via SdkMeterProviderUtil#setExemplarFilter.
• BREAKING: MetricExporter#getPreferredTemporality() has been removed and replaced with getAggregationTemporality(InstrumentType), which allows exporters to dictate the aggregation temporality on a per-instrument basis. MetricExporter#alwaysCumulative(InstrumentType) and MetricExporter#deltaPreferred(Instrument) are provided as utilities representing common configurations.
• Callbacks associated with asynchronous instruments with multiple matching views will only be called once per collection, instead of once per view per collection.
• PeriodicMetricReader will no longer call MetricExporter#export if no metrics are available.
• BREAKING: SdkMeterProviderBuilder#setMinimumCollectionInterval has been removed. Available for experimental use via SdkMeterProviderUtil#setMinimumCollectionInterval.
• Introduce lock ensuring that metric collections occur sequentially.
• Add min and max to HistogramDataPoint.

Logs

• BREAKING: Deprecated name field has been removed.

Exporter

• Upgrade to OTLP protobuf version 0.16.0.
• Jaeger and Zipkin exporters export otel.scope.name and otel.scope.version, in addition to otel.library.name and otel.library.version which are retained for backwards compatibility.
• BREAKING: Remove deprecated PrometheusCollector. Use PrometheusHttpServer instead.
• Add support for mTLS authentication to OTLP and jaeger exporters.
• Only log once if OTLP gRPC export receives UNIMPLEMENTED.
• Jaeger remote sampler sets appropriate sampling strategy type if not provided in response.
• BREAKING: The setPreferredTemporality method has been removed from OtlpGrpcMetricExporterBuilder and OtlpHttpMetricExporterBuilder. Use setAggregationTemporality(Function<InstrumentType, AggregationTemporality>) instead.

SDK Extensions

• IMPORTANT: Auto-configuration sets otel.metrics.exporter to otlp instead of none, enabling metric export by default.
• Auto-configuration added otel.java.enabled.resource-providers property for opting into specific resource providers.

Micrometer shim

• Bring micrometer shim over from opentelemetry-java-instrumentation. Artifact is available at maven coordinates io.opentelemetry:opentelemetry-micrometer1-shim:1.13.0-alpha.
• Add support for "prometheus mode", enabling better naming when exporting micrometer metrics via prometheus.

Testing

• Add int overload for equalTo attribute assertion.
• Add SpanDataAssert.hasAttribute methods.

🙇 Thank you

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

@anuraaga
@bogdandrutu
@breedx-splk
@HaloFour
@jack-berg
@jkamon
@jkwatson
@jsuereth
@kubawach
@mateuszrzeszutek
@mdii
@pokusak
@Rocksnake
@trask
@wallezhang
@zeitlinger

Version 1.12.0

This release includes many breaking changes to the metrics SDK as we move towards marking its first stable release.
Notably, if you configure metric Views or have written a custom metric exporter, many of the classes and methods will
have been moved or renamed. There are still a few remaining cleanups targeted for the next release after which there
should not be many. Thanks for bearing with us on this.

API

• New methods have been added to Context to propagate context for common Java 8 callback types
• AttributesBuilder.put now supports vararg versions for lists with AttributeKey
• Multiple metric async callbacks can be registered for the same instrument, and callbacks can be removed

SDK

• An issue with Android desugaring of the SDK has been worked around
• EXPERIMENTAL: Support for disabling resource keys with OTEL_EXPERIMENTAL_RESOURCE_DISABLED_KEYS
• Fixed handling of schemaUrl in Resource.toBuilder()
• BREAKING: Many changes to Data classes used during export
• BREAKING: Many view configuration methods have been removed

Metrics

• APIs deprecated in the previous release have been removed
• DEPRECATION: PrometheusCollector for exporting OpenTelemetry metrics with the prometheus client library has been deprecated
• EXPERIMENTAL: File-based configuration of views
• Prometheus exporter now supports JPMS modules

Logs

• DEPRECATION: LogData.getName has been deprecated for removal