# Patch Coverage Tracking

## Module
BinaryIndex

## Status
IMPLEMENTED

## Description
Dedicated patch coverage API endpoint for tracking which CVE patches are covered in binary analysis.

## Implementation Details
- **Modules**: `src/BinaryIndex/StellaOps.BinaryIndex.WebService/Controllers/`
- **Key Classes**:
  - `PatchCoverageController` (`src/BinaryIndex/StellaOps.BinaryIndex.WebService/Controllers/PatchCoverageController.cs`) - REST API controller for patch coverage queries using `IDeltaSignatureRepository`
  - `DeltaSignatureMatcher` (`src/BinaryIndex/__Libraries/StellaOps.BinaryIndex.DeltaSig/DeltaSignatureMatcher.cs`) - matches delta signatures to assess patch coverage
  - `DeltaSigService` / `DeltaSigServiceV2` (`src/BinaryIndex/__Libraries/StellaOps.BinaryIndex.DeltaSig/`) - service layer for delta-sig operations
- **Interfaces**: `IDeltaSignatureRepository` - repository for persisted delta signatures used by patch coverage queries

## E2E Test Plan
- [ ] Query patch coverage API for a known CVE and verify coverage status (covered/not covered)
- [ ] Verify patch coverage percentage calculation: submit binaries with partial patch coverage
- [ ] Verify that delta signatures for the CVE fix are used to determine coverage
- [ ] Verify API returns correct coverage for batch queries across multiple CVEs
- [ ] Verify coverage tracking updates when new delta signatures are added