Avoid null collection on decoded spans

[PerfectSlayer]

What Does This Do

This PR updates the decoded spans to avoid null collections.

Motivation

This changes will help asserting the trace / span structure and values with the upcoming rules and matchers.

Additional Notes

Contributor Checklist

• Format the title according to the contribution guidelines
• Assign the type: and (comp: or inst:) labels in addition to any other useful labels
• Avoid using close, fix, or any linking keywords when referencing an issue
  Use solves instead, and assign the PR milestone to the issue
• Update the CODEOWNERS file on source file addition, migration, or deletion
• Update public documentation with any new configuration flags or behaviors
• Once approved, use merge queue to merge the PR

Jira ticket: APMLP-1247

[chatgpt-codex-connector]

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[datadog-datadog-prod-us1]

More details

The decoder changes consistently replace absent meta_struct values with immutable empty maps across v0.4, v0.5, and v1, matching the updated smoke-test assertions. No diff-only behavioral regression was identified; local execution was attempted but the sandbox lacks the required Gradle distribution and Java 25 toolchain.

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[datadog-datadog-prod-us1]

🎯 Code Coverage (details)
• Patch Coverage: 0.00%
• Overall Coverage: 57.83% (-0.01%)

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[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	14.02 s	14.02 s	[-0.6%; +0.6%] (no difference)
startup:insecure-bank:tracing:Agent	12.96 s	13.02 s	[-1.2%; +0.3%] (no difference)
startup:petclinic:appsec:Agent	16.39 s	16.83 s	[-6.9%; +1.6%] (no difference)
startup:petclinic:iast:Agent	16.73 s	16.83 s	[-1.4%; +0.2%] (no difference)
startup:petclinic:profiling:Agent	16.80 s	16.11 s	[-0.2%; +8.8%] (no difference)
startup:petclinic:sca:Agent	16.79 s	16.71 s	[-0.6%; +1.5%] (no difference)
startup:petclinic:tracing:Agent	15.97 s	16.08 s	[-1.7%; +0.3%] (no difference)

Commit: a6e25453 · 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.

[jandro996]

LGTM! Thanks!

[PerfectSlayer]

/merge

[gh-worker-devflow-routing-ef8351]

View all feedbacks in Devflow UI.

2026-07-30 04:24:28 UTC ℹ️ Start processing command /merge

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2026-07-30 04:24:30 UTC ℹ️ MergeQueue: Stack detected — automatically merging the entire stack.

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2026-07-30 04:24:34 UTC ℹ️ Devflow: Merging stacked PRs in the following order:

1. Add test agent session token support (#12050)
2. Avoid null collection on decoded spans (#12087)

Progress updates will be sent here directly.

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2026-07-30 04:24:35 UTC ℹ️ Devflow: Merging Add test agent session token support (#12050)...

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2026-07-30 04:24:38 UTC ❌ MergeQueue

merge method 'merge' is not allowed for this repository. Supported methods are: [squash]

[PerfectSlayer]

/merge

[gh-worker-devflow-routing-ef8351]

View all feedbacks in Devflow UI.

2026-07-30 05:55:42 UTC ℹ️ Start processing command /merge

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2026-07-30 05:55:47 UTC ℹ️ MergeQueue: pull request added to the queue

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

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2026-07-30 06:59:03 UTC ℹ️ MergeQueue: This merge request was merged

[datadog-datadog-prod-us1]

More details

The decoder changes consistently normalize absent meta-struct data to immutable empty maps across v0.4, v0.5, and v1, matching the updated smoke-test consumers without changing populated values. No diff-only behavioral regression was identified; local execution was blocked by the unavailable Gradle wrapper network and Java 25 toolchain.

Was this helpful? React 👍 or 👎

_{Open Bits AI session}

_{🤖 Datadog Autotest · Commit a6e2545 · What is Autotest? · @DataDog review to ask questions · Any feedback? Reach out in #autotest}