[FFL-1720] Evaluation Logging: Storage & Network Infrastructure

[typotter]

🥞 Evaluation Logging Stacked Pull Requests 🥞

🔲 Integration & Configuration (PR #3147)
👉 Storage & Network Infrastructure (this PR)
☑️ Aggregation Engine & Test Utilities (PR #3145)
☑️FlagEvaluation Schema (PR #3166)
☑️ Event Schema & Data Models (PR #3144)
☑️ Evaluations Subfeature (PR #3159)
⎿ feature/flags-evaluations-logging (feature branch)

Datadog Internal
🎟️ Ticket: FFL-1720 - Implement Evaluation Logging for Android SDK

What does this PR do?

Implements the infrastructure for persisting evaluation events to disk and uploading them to Datadog's intake endpoint. Connects the aggregation engine (PR #3145) to the SDK Core's storage and network layer.

Motivation

We need to implement Evaluation Logging to provide comprehensive visibility into all feature flag evaluations, including defaults, errors, and successful matches. This goes beyond exposure logging by capturing aggregated metrics about evaluation frequency, error rates, and runtime default usage across all flags.

Additional Notes

Review checklist (to be filled by reviewers)

• Feature or bugfix MUST have appropriate tests (unit, integration, e2e)
• Make sure you discussed the feature or bugfix with the maintaining team in an Issue
• Make sure each commit and the PR mention the Issue number (cf the CONTRIBUTING doc)

[typotter]

• [FFL-1720] Evaluation Logging: Integration #3147
• [FFL-1720] Evaluation Logging: Storage & Network Infrastructure #3146 👈 (View in Graphite)
• [FFL-1720] Evaluation Logging: Aggregation Engine & Test Utilities #3145
• [FFL-1720] Evaluation Logging: Event Schema & Data Models #3144
• feature/flags-evaluations-logging

This stack of pull requests is managed by Graphite. Learn more about stacking.

[codecov-commenter]

Codecov Report

❌ Patch coverage is 53.09735% with 53 lines in your changes missing coverage. Please review.
✅ Project coverage is 70.87%. Comparing base (adb81d5) to head (0b4df16).

Files with missing lines	Patch %	Lines
...tadog/android/flags/internal/EvaluationsFeature.kt	2.44%	40 Missing ⚠️
...tadog/android/flags/internal/DatadogFlagsClient.kt	67.86%	6 Missing and 3 partials ⚠️
...in/kotlin/com/datadog/android/flags/FlagsClient.kt	33.33%	3 Missing and 1 partial ⚠️

Additional details and impacted files

@@                          Coverage Diff                          @@
##           feature/flags-evaluations-logging    #3146      +/-   ##
=====================================================================
- Coverage                              71.00%   70.87%   -0.13%     
=====================================================================
  Files                                    905      906       +1     
  Lines                                  33310    33418     +108     
  Branches                                5614     5635      +21     
=====================================================================
+ Hits                                   23650    23684      +34     
- Misses                                  8102     8159      +57     
- Partials                                1558     1575      +17     

Files with missing lines	Coverage Δ
...com/datadog/android/flags/internal/FlagsFeature.kt	85.07% <100.00%> (+0.46%)	⬆️
...id/flags/internal/net/EvaluationsRequestFactory.kt	100.00% <100.00%> (+25.00%)	⬆️
...gs/internal/storage/EvaluationEventRecordWriter.kt	100.00% <100.00%> (ø)
...in/kotlin/com/datadog/android/flags/FlagsClient.kt	36.67% <33.33%> (+0.14%)	⬆️
...tadog/android/flags/internal/DatadogFlagsClient.kt	88.83% <67.86%> (-2.53%)	⬇️
...tadog/android/flags/internal/EvaluationsFeature.kt	18.87% <2.44%> (-56.13%)	⬇️

... and 39 files with indirect coverage changes

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The base branch was changed.

[typotter]

/merge

[gh-worker-devflow-routing-ef8351]

View all feedbacks in Devflow UI.

2026-02-13 18:16:19 UTC ℹ️ Start processing command /merge

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2026-02-13 22:18:08 UTC ⚠️ MergeQueue: This merge request was unqueued

devflow unqueued this merge request: It did not become mergeable within the expected time