Release 1.42.0

v1.42.0 (2025-02-18)

Traces

• Deprecate exception.escaped attribute, add link to in-development semantic-conventions on how to record errors across signals.
  (#4368)
• Define randomness value requirements for W3C Trace Context Level 2.
  (#4162)

Logs

• Define how SDK implements Logger.Enabled.
  (#4381)
• Logs API should have functionality for reusing Standard Attributes.
  (#4373)

SDK Configuration

• Define syntax for escaping declarative configuration environment variable references.
  (#4375)
• Resolve various declarative config TODOs.
  (#4394)

Release 1.41.0

v1.41.0 (2025-01-21)

Logs

• Remove the deprecated Events API and SDK in favor of having Events support in the Logs API and SDK.
  (#4353)
• Remove Logger's Log Instrumentation operations.
  (#4352)
• Make all Logger operations user-facing.
  (#4352)

SDK Configuration

• Clarify that implementations should interpret timeout environment variable
  values of zero as no limit (infinity).
  (#4331)

Release 1.40.0

v1.40.0 (2024-12-12)

Context

• Adds optional GetAll method to Getter in Propagation API, allowing for the retrieval of multiple values for the same key.
  #4295

Traces

• Add in-development support for otlp/stdout exporter via OTEL_TRACES_EXPORTER.
  (#4183)
• Remove the recommendation to not synchronize access to TracerConfig.disabled.
  (#4310)

Metrics

• Add in-development support for otlp/stdout exporter via OTEL_METRICS_EXPORTER.
  (#4183)
• Remove the recommendation to not synchronize access to MeterConfig.disabled.
  (#4310)

Logs

• Add in-development support for otlp/stdout exporter via OTEL_LOGS_EXPORTER.
  (#4183)
• Remove the recommendation to not synchronize access to LoggerConfig.disabled.
  (#4310)
• Remove the in-development isolating log record processor.
  (#4301)

Events

• Deprecate Events API and SDK in favor of having Events support in the Logs API and SDK.
  (#4319)
• Change event.name attribute into top-level event name field.
  (#4320)

Common

• Lay out core principles for Specification changes.
  (#4286)

Supplementary Guidelines

• Add core principles for evaluating specification changes.
  (#4286)

OTEPs

• The open-telemetry/oteps repository was merged into the specification repository.
  (#4288)

New Contributors

• @CharlieTLe made their first contribution in #4289
• @jamesmoessis made their first contribution in #4295

Release 1.39.0

v1.39.0 (2024-11-07)

Logs

• Simplify the name "Logs Instrumentation API" to just "Logs API".
  (#4258)
• Rename Log Bridge API to Logs API. Define the existing Logger methods to be
  Log Bridge Operations. Add EmitEvent to the Logger as an Instrumentation Operation.
  (#4259)

Profiles

• Define required attributes for Mappings.
  (#4197)

Compatibility

• Add requirement to allow extending Stable APIs.
  (#4270)

SDK Configuration

• Clarify declarative configuration parse requirements for null vs empty.
  (#4269)

Common

• Define prototype for proposed features in development.
  (#4273)

New Contributors

• @florianl made their first contribution in #4197

Release 1.38.0

v1.38.0 (2024-10-10)

Traces

• Make all fields as identifying for Tracer. Previously attributes were omitted from being identifying.
  (#4161)
• Clarify that Export MUST NOT be called by simple and batching processors concurrently.
  (#4205)

Metrics

• Make all fields as identifying for Meter. Previously attributes were omitted from being identifying.
  (#4161)
• Add support for filtering attribute keys for streams via an exclude list.
  (#4188)
• Clarify that Enabled only applies to synchronous instruments.
  (#4211)
• Clarify that applying cardinality limits should be done after attribute filtering.
  (#4228)
• Mark cardinality limits as stable.
  (#4222)

Logs

• Make all fields as identifying for Logger. Previously attributes were omitted from being identifying.
  (#4161)
• Define Enabled parameters for Logger.
  (#4203)
  (#4221)
• Introduce initial placeholder for the new user-facing Logs API, adding references
  to existing API's informing of the coming changes while the definition is defined.
  (#4236)

Common

• Define equality for attributes and collection of attributes.
  (#4161)
• Update Instrumentation Scope glossary entry with correct identifying fields
  (#4244)

New Contributors

• @yuanyuanzhao3 made their first contribution in #4216
• @MSNev made their first contribution in #4236

Release 1.37.0

v1.37.0 (2024-09-13)

Traces

• Minor clarification on BatchExportingProcessor behavior.
  (#4164)
• Clarify SpanKind description, extend it to cover links, add examples of nested client spans.
  (#4178)

Metrics

• Clarify that Export MUST NOT be called by periodic exporting MetricReader concurrently.
  (#4206)

Logs

• Clarify that log record mutations are visible in next registered processors.
  (#4067)
• Clarify that Export MUST NOT be called by simple and batching processors concurrently.
  (#4173)

SDK Configuration

• Define instrumentation configuration API.
  (#4128)
• Mark exemplar filter env variable config as stable.
  (#4191)

Common

• Update instrumentation library guidance to avoid naming collisions between external and OTel instrumentations.
  (#4187)
• Add natively instrumented to glossary.
  (#4186)

New Contributors

• @javiergarea made their first contribution in #4182
• @carsonip made their first contribution in #4192

Release 1.36.0

v1.36.0 (2024-08-12)

Traces

• Remove restriction that sampler description is immutable.
  (#4137)
• Add in-development OnEnding callback to SDK SpanProcessor interface.
  (#4024)

Metrics

• Clarify metric reader / metric exporter relationship for temporality
  preference and default aggregation. Explicitly define configuration options
  for temporality preference and default aggregation of built-in exporters, and
  make default values explicit.
  (#4142)
• Add data point flags to the metric data model.
  (#4135)

Logs

• The SDK MAY provide an operation that makes a deep clone of a ReadWriteLogRecord.
  (#4090)

Baggage

• Clarify no empty string allowed in baggage names.
  (#4144)

Compatibility

• Clarify prometheus exporter should have host and port configuration options.
  (#4147)

Common

• Require separation of API and SDK artifacts.
  (#4125)

New Contributors

• @vishweshbankwar made their first contribution in #4139
• @alfiejfs made their first contribution in #4150
• @hiroyaonoe made their first contribution in #4153

Full Changelog: v1.35.0...v1.36.0

Release 1.35.0

v1.35.0 (2024-07-12)

Logs

• Add the in-development isolating log record processor.
  (#4062)

Compatibility

• Define casing for hex-encoded IDs and mark the "Trace Context in non-OTLP Log Formats" specification stable.
  (#3909)

Release 1.34.0

v1.34.0 (2024-06-11)

Context

• No changes.

Traces

• Clarify the trace SDK should log discarded events and links. (#4064)
• Add new in-development Enabled API to the Tracer. (#4063)

Metrics

• Add new in-development Enabled API to meter instruments. (#4063)

Logs

• Add the in-development Enabled API to the Logger. (#4020)

Events

• Rename event payload to body. (#4035)
• Add specification for EventLogger and EventLoggerProvider. (#4031)
• Describe the use cases for events in greater detail. (#3969)

Resource

• No changes.

OpenTelemetry Protocol

• No changes.

Compatibility

• Prometheus: Clarify location of unit suffix within metric names. (#4057)

SDK Configuration

• No changes.

Common

• OpenTelemetry clients MUST follow SemVer 2.0.0. (#4039)
• Rename "Experimental" to "Development" according to OTEP 0232. (#4061), (#4069)

Supplementary Guidelines

• Clarify that it is permissible to extend SDK interfaces without requiring a major version bump (#4030)

New Contributors

• @yijiem made their first contribution in #4050
• @JonasKunz made their first contribution in #4030

Full Changelog: v1.33.0...v1.34.0

Release 1.33.0

v1.33.0 (2024-05-09)

Context

• No changes.

Traces

• Links with invalid SpanContext are recorded.
  (#3928)

Metrics

• Change the exemplar behavior to be on by default.
  (#3994)
• Use normative language for exemplar default aggregations.
  (#4009)
• Mark Exemplars as stable.
  (#3870)
• Mark synchronous gauge as stable.
  (#4019)

Logs

• Allow implementations to export duplicate keys in a map as an opt-in option.
  (#3987)

Events

• No changes.

Resource

• No changes.

OpenTelemetry Protocol

• No changes.

Compatibility

• Add name suggestion for option to apply resource attributes as metric attributes in Prometheus exporter.
  (#3837)

SDK Configuration

• Clarify syntax for environment variable substitution regular expression
  (#4001)
• Error out on invalid identifiers in environment variable substitution.
  (#4002)
• Add end to end examples for file configuration
  (#4018)
• Clarify the schema for YAML configuration files
  (#3973)

Common

• No changes.

Supplementary Guidelines

• No changes.

New Contributors

• @weslenteche made their first contribution in #3993