fix: Preserve gRPC trace context length

[amarrtech]

What does the PR do?

Constructs the OpenTelemetry carrier value from gRPC metadata with both its pointer and explicit length. This prevents the nostd::string_view constructor from using strlen on grpc::string_ref::data() and reading beyond the metadata value, which can make valid 55-byte traceparent headers fail parsing.

Checklist

• I have read the contribution guidelines.
• I have signed the Contributor License Agreement.
• PR title reflects the change and is of format <commit_type>: <Title>.
• Changes are described in the pull request.
• Related issues are referenced.
• Populated the GitHub labels field.
• Added a test plan and verified the available tests pass.
• Verified that the PR passes existing CI.
• I ran pre-commit run --all locally; see Caveats.
• Verified copyright is correct on all changed files.
• Added succinct git squash message before merging: fix: preserve gRPC trace context length.
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Commit Type:

• fix

Related PRs:

None.

Where should the reviewer start?

src/grpc/infer_handler.h, in GrpcServerCarrier::Get.

Test plan:

• uvx pre-commit run --files src/grpc/infer_handler.h — passed, including clang-format, codespell, secret scan, merge-conflict checks, and license validation.
• git diff --check — passed.
• Compiled a C++ constructor-semantics regression harness using a 55-byte traceparent followed by a non-null byte. The pointer-only view reported length 56; the pointer-plus-size view reported 55.

Caveats:

This host does not have CMake, a built Triton server image, or the GPU test stack needed for qa/L0_trace. A repository-wide pre-commit run was attempted, but current main fails its all-files flake8 pass on existing unrelated files; the changed header passes the configured hooks in isolation.

Background

A grpc::string_ref is not required to be null-terminated. Passing only data() selects the C-string constructor and derives the length with strlen, so trace context acceptance depends on the adjacent byte in memory.

Related Issues:

• closes GitHub issue: gRPC frontend reads the traceparent metadata past its end, so OpenTelemetry drops some valid trace contexts #8984

[amarrtech]

Closing this duplicate because #8987 opened first with the same one-line fix and verification for #8984.

[greptile-apps]

Confidence Score: 5/5

[Medium risk] Fixes trace context propagation in gRPC handler.

The PR appears safe to merge.

Summary

The PR changes GrpcServerCarrier::Get to preserve the explicit length of a gRPC metadata value when returning an OpenTelemetry string view, avoiding a length calculation from a potentially non-null-terminated pointer.

_{Reviews (1) · Last reviewed commit: "fix: preserve gRPC trace context length"}