Problem
- The Go SDK masks trace flags to the sampled bit and rejects version 00
flags > 0x02.
- This drops the W3C Trace Context Level 2 random Trace ID flag (0x02)
and any forward-compatible bits.
Approach
- Treat trace flags as an 8-bit bitmask across extract, storage, and
inject.
- Accept any flags for traceparent version 00 and preserve them
unchanged.
- Interpret only known bits for behavior (sampling uses 0x01); do not
change sampling logic.
Implementation details
- propagation/trace_context.go
- Inject: emit sc.TraceFlags() without masking.
- Extract: remove opts[0] > 2 rejection; store full flags byte in
SpanContextConfig.TraceFlags.
- propagation/trace_context_test.go
- Add extract cases for 0x02 and 0x03; ensure 0x09 is preserved.
- Remove "unused bits set" from invalid cases.
- Inject cases preserve 0xff, 0x02, and 0x03.
- Future-version flag tests now expect full byte, not masked.
Closes#7635
---------
Co-authored-by: Damien Mathieu <42@dmathieu.com>
Updates the baggage implementation to comply with
https://www.w3.org/TR/baggage/#limits:
- Changed maxMembers from 180 to 64 (the W3C compliance requirement)
> The resulting baggage-string contains 64 list-members or less.
- Removed maxBytesPerMembers (4096) - this per-member limit was not part
of the W3C spec
- Added limit checking in extractMultiBaggage for multiple baggage
headers:
- Checks combined byte size across all headers (max 8192 bytes)
- Checks combined member count across all headers (max 64 members)
This uses non-deterministic truncation when handling baggage limits.
This PR contains the following updates:
| Package | Change | Age | Confidence |
|---|---|---|---|
|
[github.com/golangci/golangci-lint/v2](https://redirect.github.com/golangci/golangci-lint)
| `v2.5.0` -> `v2.6.0` |
[](https://docs.renovatebot.com/merge-confidence/)
|
[](https://docs.renovatebot.com/merge-confidence/)
|
---
> [!WARNING]
> Some dependencies could not be looked up. Check the Dependency
Dashboard for more information.
---
### Release Notes
<details>
<summary>golangci/golangci-lint
(github.com/golangci/golangci-lint/v2)</summary>
###
[`v2.6.0`](https://redirect.github.com/golangci/golangci-lint/blob/HEAD/CHANGELOG.md#v260)
[Compare
Source](https://redirect.github.com/golangci/golangci-lint/compare/v2.5.0...v2.6.0)
1. New linters
- Add `modernize` analyzer suite
2. Linters new features or changes
- `arangolint`: from 0.2.0 to 0.3.1
- `dupword`: from 0.1.6 to 0.1.7 (new option `comments-only`)
- `go-critic`: from 0.13.0 to 0.14.0 (new rules/checkers:
`zeroByteRepeat`, `dupOption`)
- `gofumpt`: from 0.9.1 to 0.9.2 ("clothe" naked returns is now
controlled by the `extra-rules` option)
- `perfsprint`: from 0.9.1 to 0.10.0 (new options: `concat-loop`,
`loop-other-ops`)
- `wsl`: from 5.2.0 to 5.3.0
3. Linters bug fixes
- `dupword`: from 0.1.6 to 0.1.7
- `durationcheck`: from 0.0.10 to 0.0.11
- `exptostd`: from 0.4.4 to 0.4.5
- `fatcontext`: from 0.8.1 to 0.9.0
- `forbidigo`: from 2.1.0 to 2.3.0
- `ginkgolinter`: from 0.21.0 to 0.21.2
- `godoc-lint`: from 0.10.0 to 0.10.1
- `gomoddirectives`: from 0.7.0 to 0.7.1
- `gosec`: from 2.22.8 to 2.22.10
- `makezero`: from 2.0.1 to 2.1.0
- `nilerr`: from 0.1.1 to 0.1.2
- `paralleltest`: from 1.0.14 to 1.0.15
- `protogetter`: from 0.3.16 to 0.3.17
- `unparam`: from
[`0df0534`](https://redirect.github.com/golangci/golangci-lint/commit/0df0534333a4)
to
[`5beb8c8`](https://redirect.github.com/golangci/golangci-lint/commit/5beb8c8f8f15)
4. Misc.
- fix: ignore some files to hash the version for custom build
</details>
---
### Configuration
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Automerge - At any time (no schedule defined).
🚦 **Automerge**: Disabled by config. Please merge this manually once you
are satisfied.
♻ **Rebasing**: Whenever PR is behind base branch, or you tick the
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🔕 **Ignore**: Close this PR and you won't be reminded about this update
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this box
---
This PR was generated by [Mend Renovate](https://mend.io/renovate/).
View the [repository job
log](https://developer.mend.io/github/open-telemetry/opentelemetry-go).
<!--renovate-debug:eyJjcmVhdGVkSW5WZXIiOiI0MS4xNTkuNCIsInVwZGF0ZWRJblZlciI6IjQxLjE1OS40IiwidGFyZ2V0QnJhbmNoIjoibWFpbiIsImxhYmVscyI6WyJTa2lwIENoYW5nZWxvZyIsImRlcGVuZGVuY2llcyJdfQ==-->
---------
Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>
Co-authored-by: dmathieu <damien.mathieu@elastic.co>
Co-authored-by: Tyler Yahn <MrAlias@users.noreply.github.com>
This PR contains the following updates:
| Package | Change | Age | Confidence |
|---|---|---|---|
| [mvdan.cc/gofumpt](https://redirect.github.com/mvdan/gofumpt) |
`v0.8.0` -> `v0.9.0` |
[](https://docs.renovatebot.com/merge-confidence/)
|
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|
---
> [!WARNING]
> Some dependencies could not be looked up. Check the Dependency
Dashboard for more information.
---
### Release Notes
<details>
<summary>mvdan/gofumpt (mvdan.cc/gofumpt)</summary>
###
[`v0.9.0`](https://redirect.github.com/mvdan/gofumpt/blob/HEAD/CHANGELOG.md#v090---2025-09-02)
[Compare
Source](https://redirect.github.com/mvdan/gofumpt/compare/v0.8.0...v0.9.0)
This release is based on Go 1.25's gofmt, and requires Go 1.24 or later.
A new rule is introduced to "clothe" naked returns for the sake of
clarity.
While there is nothing wrong with naming results in function signatures,
using lone `return` statements can be confusing to the reader.
Go 1.25's `ignore` directives in `go.mod` files are now obeyed;
any directories within the module matching any of the patterns
are now omitted when walking directories, such as with `gofumpt -w .`.
Module information is now loaded via Go's [`x/mod/modfile`
package](https://pkg.go.dev/golang.org/x/mod/modfile)
rather than executing `go mod edit -json`, which is way faster.
This should result in moderate speed-ups when formatting many
directories.
</details>
---
### Configuration
📅 **Schedule**: Branch creation - At any time (no schedule defined),
Automerge - At any time (no schedule defined).
🚦 **Automerge**: Disabled by config. Please merge this manually once you
are satisfied.
♻ **Rebasing**: Whenever PR is behind base branch, or you tick the
rebase/retry checkbox.
🔕 **Ignore**: Close this PR and you won't be reminded about this update
again.
---
- [ ] <!-- rebase-check -->If you want to rebase/retry this PR, check
this box
---
This PR was generated by [Mend Renovate](https://mend.io/renovate/).
View the [repository job
log](https://developer.mend.io/github/open-telemetry/opentelemetry-go).
<!--renovate-debug:eyJjcmVhdGVkSW5WZXIiOiI0MS45MS4xIiwidXBkYXRlZEluVmVyIjoiNDEuOTEuMSIsInRhcmdldEJyYW5jaCI6Im1haW4iLCJsYWJlbHMiOlsiU2tpcCBDaGFuZ2Vsb2ciLCJkZXBlbmRlbmNpZXMiXX0=-->
---------
Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>
Co-authored-by: dmathieu <damien.mathieu@elastic.co>
Example demonstrating how to use `SetTextMapPropagator` with a composite
propagator
Related Issue: Closes#6571
Co-authored-by: Damien Mathieu <42@dmathieu.com>
* Use gofumpt instead of gofmt in golangci-lint conf
* Run gofumpt fixes
* Format generated templates
---------
Co-authored-by: Chester Cheung <cheung.zhy.csu@gmail.com>
* docs(typos): Run codespell to fix typos
There were a lot of typos through the repository, so I ran
[codespell][], a tool for automatically fixing typos, to fix them.
```console
make codespell
```
There's already a tool called [misspell][] that's supposed to take care
of this, but misspell hasn't been updated for 6 years, and it doesn't
seem to be catching any of the typos that codespell can.
[codespell]: https://github.com/codespell-project/codespell
[misspell]: https://github.com/client9/misspell
* Revert and ignore spelling for Consequentially
* Add GH workflow for codespell
* Revert GH Workflow and Makefile for codespell
Per @pellared, since there's no instructions for setting up codespell,
it was suggested that the changes for setting up a workflow and section
in Makefile include instructions for setting up codespell as well.
* Revert spelling on consequently
---------
Co-authored-by: Chester Cheung <cheung.zhy.csu@gmail.com>
Co-authored-by: Tyler Yahn <MrAlias@users.noreply.github.com>
* Fix baggage.NewMember to decode the accepted value
`value` is decoded and stored after validating the input parameters.
Corresponding test cases are modified so that we can make sure `value` is properly encoded before creating Member.
* fix md lint
* add function document to NewMember for value encoding and decoding
* remove redundant comments and fix CHANGELOG.md
* fix wrong PR number in the changelog
* fix wrong PR number
* fix md-lint
Co-authored-by: Chester Cheung <cheung.zhy.csu@gmail.com>
* Update versions file for 1.0.0 release
* Prepare stable-v1 for version v1.0.0
* Update trace signal status in documentation
* Update changelog
* Update CHANGELOG.md
Co-authored-by: Robert Pająk <pellared@hotmail.com>
Co-authored-by: Robert Pająk <pellared@hotmail.com>
* Simplify trace_context tests
Refactor the propagation/trace_context tests to be targeted at testing
the propagator functionality only and remove extraneous dependencies.
Fix the TraceContext Inject method from injecting the tracestate header
if no value exists.
* Add changes to changelog
* Rename baggage context file
* Initial baggage implementation
* Initial tests
* More tests
* Update baggage context functionality
* Add New method to baggage pkg
* Update namedtracer example
* URL encode baggage values
* Refactor and use internal baggage pkg
* Update OpenTracing bridge
* Update baggage propagator
* Fix lint and test errors
* Add changes to changelog
* Apply suggestions from code review
* Rename testcase field per suggestion
* Update test to verify last-one-wins semantics
* Explicitly seed random numbers with static seed in tests
* Parse Member key/value with string split
* Add test for member parse with equal signs in value
* Trim whitespaces for member key/value
* Refactor TraceState
* Update tracecontext propagator to use new TraceState
* Add TraceStateFromKeyValues to oteltest
* Use oteltest to test TraceState
* Replace IsEmpty with Len for TraceState
* Replace ParseTraceState with ParseTraceStateString
* Clean up naming
* Add immutability test for TraceState
* Add changes to changelog
* Fixes
* Document argument type change in changelog
* Address feedback
Remove circularity of TestTraceStateLen.
* Make TraceFlags spec-compliant
* Remove `trace.FlagsDebug` and `trace.FlagsDeferred`
* These are used only by the B3 propagator and will be handled there in the `context.Context`
* Make `trace.TraceFlags` a defined type, aliasing `byte`
* Move `IsSampled` method from `trace.SpanContext` to `trace.TraceFlags`
* Add `Sampled(bool)` method to `trace.TraceFlags`
* Implement `Stringer` and `json.Marshaler` for `trace.TraceFlags`
Signed-off-by: Anthony J Mirabella <a9@aneurysm9.com>
* Rename `TraceFlags.Sampled()` to `TraceFlags.WithSampled()` for consistency
* Restore `SpanContext.IsSampled()` method.
Signed-off-by: Anthony J Mirabella <a9@aneurysm9.com>
* Store Span instead of local/remote SpanContext in Context
Now that the SpanContext has a remote identifier, storing a Span's
SpanContext two separate ways in a Context (one for local another for
remote) is unnecessary and adds complication throughout the project when
determining heredity of a Span. This moves to storing the Span directly
in the Context uniformly (for both local and remote) as current Span. In
the process, it updates the getter/setter functionality the `trace`
package provides and replaces the distributed heredity logic throughout
the project with just using the current Span as the parent if it exists.
* Update trace/context.go
Co-authored-by: Anthony Mirabella <a9@aneurysm9.com>
* Assert propagators context remote state
Co-authored-by: Anthony Mirabella <a9@aneurysm9.com>
How the tracecontext is extracted is important if the user wants to
interact with the extracted SpanContext (i.e. as a remote span context
instead of a current span context). This makes it clear where it will be
extracted and what behavior to expect if the tracecontext is invalid.
* Add remote property to SpanContext
* Set SpanContext.remote when extracting context in TraceContext propagator
* Ensure remote flag is set when inserting remote SpanContext into context
* Ensure tests are expecting remote flag in SpanContext where appropriate
* Update CHANGELOG.md
* Apply PR feedback
Co-authored-by: Tyler Yahn <MrAlias@users.noreply.github.com>
Co-authored-by: Tyler Yahn <MrAlias@users.noreply.github.com>
* Make SpanContext Immutable
* Adds NewSpanContext() constructor and SpanContextConfig{} struct for
constructing a new SpanContext when all fields are known
* Adds With<field>() methods to SpanContext for deriving a SpanContext
with a single field changed.
* Updates all uses of SpanContext to use the new API
Signed-off-by: Anthony J Mirabella <a9@aneurysm9.com>
* Update CHANGELOG.md
Signed-off-by: Anthony J Mirabella <a9@aneurysm9.com>
* Add tests for new SpanContext constructor and derivation
Signed-off-by: Anthony J Mirabella <a9@aneurysm9.com>
* Address PR feedback
* Fix new uses of SpanContext from main
* TraceContext propagator now handles `tracestate`.
Signed-off-by: Anthony J Mirabella <a9@aneurysm9.com>
* Prevent invalid tracestate from invalidating traceparent.
Signed-off-by: Anthony J Mirabella <a9@aneurysm9.com>
* Fail tests early if unable to construct expected TraceContext
Signed-off-by: Anthony J Mirabella <a9@aneurysm9.com>
* Add TraceState to API
* Add tests for TraceState
* Update related tests
- stdout exporter test
- SDK test
* Update OTLP span transform
* Update CHANGELOG
* Change TraceState to struct instead of pointer
- Adjust tests for trace API
- Adjust adjacent parts of codebase (test utils, SDK etc.)
* Add methods to assert equality
- for type SpanContext, if SpanID, TraceID, TraceFlag and TraceState are
equal
- for type TraceState, if entries of both respective trace states are
equal
Signed-off-by: Matej Gera <matejgera@gmail.com>
* Copy values for new TraceState, adjust tests
* Use IsEqualWith in remaining tests instead of assertion func
* Further feedback, minor improvements
- Move IsEqualWith method to be only in test package
- Minor improvements, typos etc.
Co-authored-by: Tyler Yahn <MrAlias@users.noreply.github.com>
* Move global code to toplevel package
* Move version function to toplevel package
* Update changelog
Co-authored-by: Tyler Yahn <MrAlias@users.noreply.github.com>
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Matthieu MOREL
Nikhil Mantri
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James Moessis
Jono
Kevin Burke
Damien Mathieu
Tyler Yahn
Robert Pająk
xiehuc
Charlie Le
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Aaron Clawson
Yoshi Yamaguchi
Anthony Mirabella
Anderson Queiroz
Punya Biswal
Daniil Rutskiy
Matej Gera
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