[dougqh]

What Does This Do

Spring Web MVC (3.1, 6.0) and Spring WebFlux now set their span tags with KnownTags ids instead of string literals. That's 7 call sites:

tag	where
view.name, view.type	Web MVC 3.1 and 6.0 SpringWebHttpServerDecorator (view render spans)
handler.type	WebFlux HandlerAdapterAdvice
request.predicate	WebFlux functional routes
event, message	WebFlux client cancellation

Motivation

This is the next family moved onto ids, following the servlet/JSP PR. Every tag was already registered on the spring.view.render, spring.webflux.handler and spring.webflux.client span types, so the change is mechanical.

Additional Notes

• No behavior change. For a known tag, the core span's setTag(String, …) resolves the name and calls setTag(long, …). This PR calls the id setter directly.
• Stacked on Name KnownTags ids after their tags and fail on constant clashes (tag registry rollout) #13061. It doesn't depend on the other rollout PRs.
• Testing: spring-webflux-5.0 (280), spring-webmvc-3.1 (412) and spring-webmvc-6.0 (160) pass, and spotless is clean.

🤖 Generated with Claude Code

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-11-04T01:17:35.896818Z	f2b6261	Draft marked ready

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[datadog-official]

More details

Each replacement uses the registry ID matching its original tag name and retains the existing setter behavior for Spring MVC views and WebFlux handlers, routes, and cancellations.

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[datadog-official]

🎯 Code Coverage (details)
• Patch Coverage: 100.00%
• Overall Coverage: 59.99% (+0.00%)

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🔗 Commit SHA: b8a3cb3 | Docs | Give us feedback!}

[dd-octo-sts]

🟢 Java Benchmark SLOs — All performance SLOs passed

Suite	Status
Startup	🟢 pass

SLO thresholds are defined here based on automatically generated metrics. A warning is raised when results are within 5% of the threshold.

PR vs. master results

Scenario	Candidate	master	Δ (95% CI of mean)
startup:insecure-bank:iast:Agent	14.90 s	14.72 s	[+0.3%; +2.2%] (maybe worse)
startup:insecure-bank:tracing:Agent	13.56 s	13.71 s	[-1.9%; -0.3%] (maybe better)
startup:petclinic:appsec:Agent	16.99 s	17.01 s	[-1.1%; +0.9%] (no difference)
startup:petclinic:iast:Agent	16.79 s	17.01 s	[-2.2%; -0.4%] (maybe better)
startup:petclinic:profiling:Agent	16.14 s	15.61 s	[-5.0%; +11.8%] (unstable)
startup:petclinic:sca:Agent	17.02 s	16.89 s	[-0.2%; +1.7%] (no difference)
startup:petclinic:tracing:Agent	16.12 s	15.90 s	[-3.0%; +5.8%] (no difference)

Commit: b8a3cb3a · CI Pipeline · Benchmarking Platform UI

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Load and DaCapo benchmarks can be triggered manually in the GitLab pipeline. Results will appear in the Benchmarking Platform UI after completion.

[ygree]

IDM reviewed

[datadog-official]

The constant rename leaves reflective bucket-hash validation filtering for _ID, silently excluding ordinary tag IDs from checks intended to cover the whole registry.

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_{🤖 Bits Code Review · Commit b3b5413}

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Findings that could not be posted inline

build-logic/tag-registry/src/main/kotlin/datadog/buildlogic/tagRegistry/KnownTagsEmitter.kt:47

Update reflective ID discovery alongside the constant rename

Removing the ID suffix leaves TagMapBucketHashTest.knownTagIds() filtering fields with endsWith("_ID"). It now excludes ordinary IDs such as HTTP_METHOD and HTTP_ROUTE, silently weakening checks intended to validate every registered tag's bucket-hash uniqueness and slot placement. Update that collector to discover static long fields and validate them with KnownTagCodec.isKnown(), as TagMapTagHashTest already does. The required fix is outside the changed lines.

React: 👍 useful · 👎 wrong · 😕 unclear · 👀 right, but not acting on it

What each reaction means

• 👍 Useful: correct, and you're fixing it or will.
• 👎 Wrong: the finding is incorrect, for example the bug can't happen or the code was misread.
• 😕 Unclear: you can't tell what it means or why it matters.
• 👀 Right, not acting: correct, but intended, out of scope for this PR, a known risk, or too minor.

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[datadog-official]

More details

The Spring tag IDs resolve to the same keys as the replaced strings, and the wider constant rename remains consistent with the registry and its callers.

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[dougqh]

/merge

[gh-worker-devflow-routing-ef8351]

View all feedbacks in Devflow UI.

2026-11-06 18:36:40 UTC ℹ️ Start processing command /merge

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2026-11-06 18:36:45 UTC ℹ️ MergeQueue: pull request added to the queue

The expected merge time in master is approximately 1h (p90).

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2026-11-06 20:20:54 UTC ℹ️ MergeQueue: This merge request was merged