CHANGELOG.md

Changelog

The full list of changes can be found in the compare view for the respective release at https://github.com/open-telemetry/opentelemetry-proto/releases.

Unreleased

Added

• docs: add response size limitation for HTTP body and gRPC messages. #781

Changed

Fixed

Removed

1.10.0 - 2026-03-09

Added

• profiles: introduce reference based attributes #733

Changed

• docs: Add more clarity to experiments. #771
• profiles: clarify Sample message usage guidance docs. #742
• profiles: improve Sample message clarity and usage documentation. #724
• profiles: clarify the profile and sample timestamps relationship. #744
• common: rename ref suffix to strindex #768

Fixed

• examples: Represent uint64 and fixed64 fields as strings in metrics.json. #748
• logs: SEVERITY_NUMBER_UNSPECIFIED can be used as the severity_number field is optional. #736

1.9.0 - 2025-10-31

Added

• profiles: drop field profile.comment_strindices. #729
• profiles: clarify the original payload field comments. #722
• profiles: add a note about cardinality implications for attribute values. #713

Changed

• profiles: clarify dictionary guidelines: duplicates and other restrictions. #732
• profiles: clarify the original payload field comments. #722
• profiles: rename line -> lines and sample -> samples since they are repeated fields. #712
• profiles: document more explicitly the dictionary zero element requirement. #711
• all: drop attribute values restrictions. #707
  ⚠️ IMPORTANT: OTLP consumers are expected to accept attribute values that were previously considered invalid. All attributes can now contain:
  • empty values,
  • bytes values,
  • array values different than array of string values, bool values, int values, double values,
  • kvlist values.

Fixed

• all: fix schema_url comments to include scope field coverage. #727
• all: add missing field comments. #717

Removed

• profiles: drop field profile.comment_strindices. #729
• profiles: remove aggregation temporality enum and field. #710

1.8.0 - 2025-09-02

Changed

• profiles: drop gzip requirement. #661
• profiles: avoid optional keyword usage. #659
• profiles: make profile_id optional. #665
• profiles: use single Profile.sample_type and clarify use of timestamps. #649
• all: add notes about the attribute values restrictions. #683
  ⚠️ IMPORTANT: These restrictions can be dropped in a future minor release.
• profiles: clarify usage of the zero value as the first element of tables in ProfilesDictionary. #688, #698
• profiles: unsigned time_nanos and duration_nanos in Profile. #692
• profiles: improve attribute encoding in ProfilesDictionary. #672
• profiles: simplify profile stack trace representation. #708

Fixed

• examples: fix OTLP JSON Event example body. #666
• docs: minor specification fixes around UNAVAILABLE and RetryInfo. #669

Removed

• profiles: remove default_sample_type. #679
• profiles: remove has_* debug info fields, they are moving to attributes. #595
• profiles: remove Location.is_folded. #690

1.7.0 - 2025-05-19

Added

• profiles: introduce Dictionary message in ProfilesData, and move the lookup tables into it. #650

1.6.0 - 2025-04-29

Added

• resource: Add EntityRef. #635

Changed

• logs: Stabilize event_name field in LogRecord message. #643
• profiles: Move the lookup tables to ProfilesData. #644
• profiles: Move default sample_type from the string table to sample_type. #620

1.5.0 - 2024-12-12

Added

• all: Add note about schema_url format (including version). #605
• logs: Add top-level event_name field to log records instead of event.name attribute. #600

Removed

• profiles: Remove unused Label definition. #602
• profiles: drop duplicate attributes field in message Profile. #606

1.4.0 - 2024-11-20

Added

• metrics: Add resource attributes and scope to metrics proto diagram. #519
• metrics: Added json example for exponential histogram. #580

Changed

• metrics: Clarify aggregation temporality for Summary metric type. #591
• docs: Remove HTTP 1.1 restriction from Protocol Details #571
• docs: Update specification to include development profiles #582
• docs: update references to logging exporter #581
• Makefile: exclude Profiles protocol from breaking-changes #576
• Makefile: exclude Profiles service from breaking changes too #586
• profiles: align type of index into string table #557
• profiles: drop Sample.stacktrace_id_index #575
• profiles: drop BuildIdKind #584
• profiles: drop Sample.label #583
• profiles: drop Location.type_index #578
• profiles: Rename profiles v1experimental to v1development #585
• profiles: Make mapping in Profile optional #556
• profiles: Fold the content of pprofextended.proto into profiles.proto, removing ProfileContainer. #590
• profiles: Improve lookup table pattern use in profiles. #592
• profiles: Renovations to experimental profiling schema. #596

1.3.2 - 2024-06-28

Changed

• profiles: add missing java_package option to pprofextended. #558

1.3.1 - 2024-05-07

Changed

• profiles: fix versioning in selector. #551

1.3.0 - 2024-04-24

Added

• Add new profile signal. #534

1.2.0 - 2024-03-29

Added

• Indicate if a Span's parent or link is remote using 2 bit flag. #484
• Add metric.metadata for supporting additional metadata on metrics #514
• Add example of an Event #538

Changed

1.1.0 - 2024-01-10

Full list of differences found in this compare.

Added

• Add flags field to Span and Span/Link for W3C-specified Trace Context flags. #503

Changed

• Update and fix OTLP JSON examples. #516, #510, #499
• Remove irrelevant comments from metric name field. #512
• Add comment to explain schema_url fields. #504

1.0.0 - 2023-07-03

Full list of differences found in this compare.

Maturity

• Add note about the possibility to have unstable components after 1.0.0 #489
• Add maturity JSON entry per package #490

0.20.0 - 2023-06-06

Full list of differences found in this compare.

Maturity

• Declare OTLP/JSON Stable. #436 #435
• Provide stronger symbolic stability guarantees. #432
• Clarify how additive changes are handled. #455

Changed

• Change the exponential histogram boundary condition. #409
• Clarify behavior for empty/not present/invalid trace_id and span_id fields. #442
• Change the collector trace endpoint to /v1/traces. #449

Added

• Introduce zero_threshold field to ExponentialHistogramDataPoint. #441 #453

Removed

• Delete requirement to generate new trace/span id if an invalid id is received. #444

0.19.0 - 2022-08-03

Full list of differences found in this compare.

Changed

• Add csharp_namespace option to protos. (#399)
• Fix some out-of-date urls which link to specification. (#402)
• 🛑 [BREAKING] Delete deprecated InstrumentationLibrary, InstrumentationLibraryLogs, InstrumentationLibrarySpans and InstrumentationLibraryMetrics messages. Delete deprecated instrumentation_library_logs, instrumentation_library_spans and instrumentation_library_metrics fields.

Added

• Introduce Scope Attributes. #395
• Introduce partial success fields in Export<signal>ServiceResponse. #414

0.18.0 - 2022-05-17

Full list of differences found in this compare.

Changed

• Declare logs Stable. (#376)
• Metrics ExponentialHistogramDataPoint makes the sum optional (follows the same change in HistogramDataPOint in 0.15). #392

0.17.0 - 2022-05-06

Full list of differences found in this compare.

Changed

• Introduce optional min and max fields to the Histogram and ExponentialHistogram data points. (#279)

0.16.0 - 2022-03-31

Full list of differences found in this compare.

Removed

• Remove deprecated LogRecord.Name field (#373).

0.15.0 - 2022-03-19

Full list of differences found in this compare.

Changed

• Rename InstrumentationLibrary to InstrumentationScope (#362)

Added

• Use optional for sum field to mark presence (#366)

0.14.0 - 2022-03-08

Full list of differences found in this compare.

Removed

• Deprecate LogRecord.Name field (#357)

0.13.0 - 2022-02-10

Full list of differences found in this compare.

Changed

• Swagger generation updated to openapiv2 due to the use of an updated version of protoc in otel/build-protobuf
• Clarify attribute key uniqueness requirement (#350)
• Fix path to Go packages (#360)

Added

• Add ObservedTimestamp to LogRecord. (#351)
• Add native kotlin support (#337)

Removed

• Remove unused deprecated message StringKeyValue (#358)
• Remove experimental metrics config service (#359)

0.12.0 - 2022-01-19

Full list of differences found in this compare.

Changed

• Rename logs to log_records in InstrumentationLibraryLogs. (#352)

Removed

• Remove deprecated messages and fields from traces. (#341)
• Remove deprecated messages and fields from metrics. (#342)

0.11.0 - 2021-10-07

Full list of differences found in this compare.

Added

• ExponentialHistogram is a base-2 exponential histogram described in OTEP 149. (#322)
• Adds TracesData, MetricsData, and LogsData container types for common use in transporting multiple ResourceSpans, ResourceMetrics, and ResourceLogs. (#332)

0.10.0 - 2021-09-07

Full list of differences found in this compare.

Maturity

• collector/logs/* is now considered Beta. (#311)
• logs/* is now considered Beta. (#311)

Added

• Metrics data points add a flags field with one bit to represent explicitly missing data. (#316)

0.9.0 - 2021-04-12

Full list of differences found in this compare.

Maturity

• collector/metrics/* is now considered stable. (#305)

Changed: Metrics

• 🛑 [DATA MODEL CHANGE] Histogram/Summary sums must be monotonic counters of events (#302)
• 🛑 [DATA MODEL CHANGE] Clarify requirements and semantics for start time (#295)
• 🛑 [BREAKING] Deprecate labels field from NumberDataPoint, HistogramDataPoint, SummaryDataPoint and add equivalent attributes field (#283)
• 🛑 [BREAKING] Deprecate filtered_labels field from Exemplars and add equivalent filtered_attributes field (#283)

Added

• Common - Add bytes (binary) as data type to AnyValue (#297)
• Common - Add schema_url fields as described in OTEP 0152 (#298)

Removed

• Remove if no changes for this section before release.

0.8.0 - 2021-03-23

Full list of differences found in this compare.

Historical breaking change notice

Release 0.8 was the last in the line of releases marked as "unstable". This release broke compatibility in more ways than were recognized and documented at the time of its release. In particular, #278 created the NumberDataPoint type and used it in several locations in place of the former DoubleDataPoint. The new oneof in NumberDataPoint re-used the former DoubleDataPoint tag number, which means that pre-0.8 DoubleSum and DoubleGauge points would parse correctly as a 0.8 Sum and Gauge points containing double-valued numbers.

However, by virtue of a syntax = "proto3" declaration, the protocol compiler for all versions of OTLP have not included field presence, which means 0 values are not serialized. The result is that valid OTLP 0.7 DoubleSum and DoubleGauge points would not parse correctly as OTLP 0.8 data. Instead, they parse as NumberDataPoint with a missing value in the oneof field.

Changed: Metrics

• 🛑 [DEPRECATION] Deprecate IntSum, IntGauge, and IntDataPoint (#278)
• 🛑 [DEPRECATION] Deprecate IntExemplar (#281)
• 🛑 [DEPRECATION] Deprecate IntHistogram (#270)
• 🛑 [BREAKING] Rename DoubleGauge to Gauge (#278)
• 🛑 [BREAKING] Rename DoubleSum to Sum (#278)
• 🛑 [BREAKING] Rename DoubleDataPoint to NumberDataPoint (#278)
• 🛑 [BREAKING] Rename DoubleSummary to Summary (#269)
• 🛑 [BREAKING] Rename DoubleExemplar to Exemplar (#281)
• 🛑 [BREAKING] Rename DoubleHistogram to Histogram (#270)
• 🛑 [DATA MODEL CHANGE] Make explicit bounds compatible with OM/Prometheus (#262)

0.7.0 - 2021-01-28

Full list of differences found in this compare.

Maturity

$$$Protobuf Encodings:**

• collector/metrics/* is now considered Beta. (#223)
• collector/logs/* is now considered Alpha. (#228)
• logs/* is now considered Alpha. (#228)
• metrics/* is now considered Beta. (#223)

Changed

• Common/Logs/Metrics/Traces - Clarify empty instrumentation (#245)

Added

• Metrics - Add SummaryDataPoint support to Metrics proto (#227)

0.6.0 - 2020-10-28

Full list of differences found in this compare.

Maturity

• Clarify maturity guarantees (#225)

Changed

• Traces - Deprecated old Span status code and added a new status code according to specification (#224) ** Marked for removal 2021-10-22 given Stability Guarantees.
• Rename ProbabilitySampler to TraceIdRatioBased (#221)

0.5.0 - 2020-08-31

Full list of differences found in this compare.

Maturity Changes

Protobuf Encodings:

• collector/trace/* is now Stable.
• common/* is now Stable.
• resource/* is now Stable.
• trace/trace.proto is now Stable. (#160)

JSON Encodings:

• All messages are now Alpha.

Changed

• 🛑 [BREAKING] Metrics - protocol was refactored, and lots of breaking changes.
  • Removed MetricDescriptor and embedded into Metric and the new data types.
  • Add new data types Gauge/Sum/Histogram.
  • Make use of the "AggregationTemporality" into the data types that allow that support.
• Rename enum values to follow the proto3 style guide.

Added

• Enable build to use docker image otel/build-protobuf to be used in CI. ** Can also be used by the languages to generate protos.

Removed

• 🛑 [BREAKING] Remove generated golang structs from the repository

Errata

The following was announced in the release, but has not yet been considered stable. Please see the latest README.md for actual status.

This is a Release Candidate to declare Metrics part of the protocol Stable.

0.4.0 - 2020-06-23

Full list of differences found in this compare.

Changed

• Metrics - Add temporality to MetricDescriptor (#140).

Added

• Metrics - Add Monotonic Types (#145)
• Common/Traces - Added support for arrays and maps for attribute values (AnyValue) (#157).

Removed

• 🛑 [BREAKING] Metrics - Removed common labels from MetricDescriptor (#144).

Errata

The following was announced in the release, but this was not considered Stable until v0.5.0

This is a Release Candidate to declare Traces part of the protocol Stable.

0.3.0 - 2020-03-23

• Initial protos for trace, metrics, resource and OTLP.