# Mermaid.js and GraphViz Diagram Renderers

## Module
Web

## Status
VERIFIED

## Description
Reusable diagram rendering components - Mermaid.js renderer for flowcharts/sequence diagrams with theme support, and GraphViz DOT renderer using WASM (@viz-js/viz) for graph visualizations with multiple engine support (dot, neato, fdp, etc.).

## Implementation Details
- **Feature directory**: `src/Web/StellaOps.Web/src/app/shared/components/visualization/`
- **Components**:
  - `graphviz-renderer` (`src/Web/StellaOps.Web/src/app/shared/components/visualization/graphviz-renderer.component.ts`)
  - `mermaid-renderer` (`src/Web/StellaOps.Web/src/app/shared/components/visualization/mermaid-renderer.component.ts`)
- **Source**: Feature matrix scan

## E2E Test Plan
- **Setup**:
  - [ ] Log in with a user that has appropriate permissions
  - [ ] Navigate to the relevant page/section where this feature appears
  - [ ] Ensure test data exists (scanned artifacts, SBOM data, or seed data as needed)
- **Core verification**:
  - [ ] Verify the visualization renders correctly with sample data
  - [ ] Verify interactive elements (hover tooltips, click-to-drill-down) work
  - [ ] Verify the visualization handles empty/minimal data gracefully
- **Edge cases**:
  - [ ] Verify graceful handling when backend API is unavailable (error state)
  - [ ] Verify responsive layout at different viewport sizes
  - [ ] Verify accessibility (keyboard navigation, screen reader labels, ARIA attributes)
## Verification
- Run: docs/qa/feature-checks/runs/web/mermaid-js-and-graphviz-diagram-renderers/run-001/
- Tier 0 (source): pass (	ier0-source-check.json)
- Tier 1 (build/tests): pass (	ier1-build-check.json)
- Tier 2 (behavior): pass (	ier2-e2e-check.json)
- Verified on (UTC): 2026-02-11T08:09:51Z