feat(relay): Add COOP (Cross-Origin-Opener-Policy) report support

[oioki]

Summary

Implements support for Cross-Origin-Opener-Policy (COOP) reports in Relay, following the same pattern as Network Error Logging (NEL) reports. COOP reports are sent by browsers when cross-origin isolation policies are violated, helping developers identify and fix security issues.

Changes

• ✅ Add COOP protocol definitions (relay-event-schema/src/protocol/coop.rs)
• ✅ Add /api/{project_id}/coop/ endpoint for receiving reports
• ✅ Add COOP processor to convert reports to log events
• ✅ Add COOP normalization with violation type mapping to human-readable messages
• ✅ Add COOP item type to envelope processing pipeline
• ✅ Add integration tests for COOP report handling

Implementation Details

COOP reports are converted to log events with:

• Origin: auto.http.browser_report.coop
• Severity: error (enforce mode) or warn (report-only mode)
• Attributes: disposition, effective policy, violation type, URLs, source location

Supported violation types:

• navigate-to-document / navigate-from-document - Browsing context group switches
• access-from-coop-page-to-* - Blocked outbound access attempts
• access-to-coop-page-from-* - Blocked inbound access attempts

Architecture

Follows the NEL report pattern:

1. Browser sends COOP report to /api/{project_id}/coop/
2. Report is wrapped in envelope with ItemType::Coop
3. Processor converts to log event with structured attributes
4. Normalizer maps violation types to descriptive messages
5. Log is stored in the logs product

Test plan

• Code compiles successfully (cargo check)
• Integration tests added for both navigation and access violations
• Manual testing can be done by configuring COOP headers:

Cross-Origin-Opener-Policy: same-origin; report-to="coop-endpoint"
Report-To: {"group":"coop-endpoint","max_age":86400,"endpoints":[{"url":"https://relay.example.com/api/PROJECT_ID/coop/?sentry_key=KEY"}]}

Testing checklist

• Run integration tests: pytest tests/integration/test_coop.py -v
• Verify COOP reports are converted to logs with correct attributes
• Verify log levels match disposition (enforce=error, reporting=warn)
• Verify all violation types have proper message mapping

References

• COOP Reporting API Explainer
• Cross-Origin-Opener-Policy MDN
• Reporting API Specification

🤖 Generated with Claude Code

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Cursor Bugbot has reviewed your changes and found 1 potential issue.

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Use-after-move: body.disposition accessed after being consumed

High Severity

The body.disposition field is moved at line 110 via map_value(self, ...) which takes ownership. Later at line 134, the code attempts to access body.disposition.value() to determine the log level, but this value has already been consumed. This is a use-after-move ownership violation. The NEL implementation avoids this by extracting values needed later (like error_type) before moving fields. The fix is to either clone body.disposition before calling map_value, or extract the disposition value earlier for reuse in both the attribute and level determination.

Additional Locations (1)

• relay-event-normalization/src/normalize/coop.rs#L109-L110