191 lines
		
	
	
		
			8.7 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
			
		
		
	
	
			191 lines
		
	
	
		
			8.7 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
| # ARCHITECTURE.md — **StellaOps.Feedser**
 | ||
| 
 | ||
| > **Goal**: Build a sovereign-ready, self-hostable **feed-merge service** that ingests authoritative vulnerability sources, normalizes and de-duplicates them into **MongoDB**, and exports **JSON** and **Trivy-compatible DB** artifacts.
 | ||
| > **Form factor**: Long-running **Web Service** with **REST APIs** (health, status, control) and an embedded **internal cron scheduler**. Controllable by StellaOps.Cli (# stella db ...)
 | ||
| > **No signing inside Feedser** (signing is a separate pipeline step).
 | ||
| > **Runtime SDK baseline**: .NET 10 Preview 7 (SDK 10.0.100-preview.7.25380.108) targeting `net10.0`, aligned with the deployed api.stella-ops.org service.
 | ||
| > **Four explicit stages**:
 | ||
| >
 | ||
| > 1. **Source Download** → raw documents.
 | ||
| > 2. **Parse & Normalize** → schema-validated DTOs enriched with canonical identifiers.
 | ||
| > 3. **Merge & Deduplicate** → precedence-aware canonical records persisted to MongoDB.
 | ||
| > 4. **Export** → JSON or TrivyDB (full or delta), then (externally) sign/publish.
 | ||
| 
 | ||
| ---
 | ||
| 
 | ||
| ## 1) Naming & Solution Layout
 | ||
| 
 | ||
| **Source connectors** namespace prefix: `StellaOps.Feedser.Source.*`
 | ||
| **Exporters**:
 | ||
| 
 | ||
| * `StellaOps.Feedser.Exporter.Json`
 | ||
| * `StellaOps.Feedser.Exporter.TrivyDb`
 | ||
| 
 | ||
| **Projects** (`/src`):
 | ||
| 
 | ||
| ```
 | ||
| StellaOps.Feedser.WebService/        # ASP.NET Core (Minimal API, net10.0 preview) WebService + embedded scheduler
 | ||
| StellaOps.Feedser.Core/              # Domain models, pipelines, merge/dedupe engine, jobs orchestration
 | ||
| StellaOps.Feedser.Models/            # Canonical POCOs, JSON Schemas, enums
 | ||
| StellaOps.Feedser.Storage.Mongo/     # Mongo repositories, GridFS access, indexes, resume "flags"
 | ||
| StellaOps.Feedser.Source.Common/     # HTTP clients, rate-limiters, schema validators, parsers utils
 | ||
| StellaOps.Feedser.Source.Cve/
 | ||
| StellaOps.Feedser.Source.Nvd/
 | ||
| StellaOps.Feedser.Source.Ghsa/
 | ||
| StellaOps.Feedser.Source.Osv/
 | ||
| StellaOps.Feedser.Source.Jvn/
 | ||
| StellaOps.Feedser.Source.CertCc/
 | ||
| StellaOps.Feedser.Source.Kev/
 | ||
| StellaOps.Feedser.Source.Kisa/
 | ||
| StellaOps.Feedser.Source.CertIn/
 | ||
| StellaOps.Feedser.Source.CertFr/
 | ||
| StellaOps.Feedser.Source.CertBund/
 | ||
| StellaOps.Feedser.Source.Acsc/
 | ||
| StellaOps.Feedser.Source.Cccs/
 | ||
| StellaOps.Feedser.Source.Ru.Bdu/     # HTML→schema with LLM fallback (gated)
 | ||
| StellaOps.Feedser.Source.Ru.Nkcki/   # PDF/HTML bulletins → structured
 | ||
| StellaOps.Feedser.Source.Vndr.Msrc/
 | ||
| StellaOps.Feedser.Source.Vndr.Cisco/
 | ||
| StellaOps.Feedser.Source.Vndr.Oracle/
 | ||
| StellaOps.Feedser.Source.Vndr.Adobe/
 | ||
| StellaOps.Feedser.Source.Vndr.Apple/
 | ||
| StellaOps.Feedser.Source.Vndr.Chromium/
 | ||
| StellaOps.Feedser.Source.Vndr.Vmware/
 | ||
| StellaOps.Feedser.Source.Distro.RedHat/
 | ||
| StellaOps.Feedser.Source.Distro.Ubuntu/
 | ||
| StellaOps.Feedser.Source.Distro.Debian/
 | ||
| StellaOps.Feedser.Source.Distro.Suse/
 | ||
| StellaOps.Feedser.Source.Ics.Cisa/
 | ||
| StellaOps.Feedser.Source.Ics.Kaspersky/
 | ||
| StellaOps.Feedser.Normalization/     # Canonical mappers, validators, version-range normalization
 | ||
| StellaOps.Feedser.Merge/             # Identity graph, precedence, deterministic merge
 | ||
| StellaOps.Feedser.Exporter.Json/
 | ||
| StellaOps.Feedser.Exporter.TrivyDb/
 | ||
| StellaOps.Feedser.<Component>.Tests/  # Component-scoped unit/integration suites (Core, Storage.Mongo, Source.*, Exporter.*, WebService, etc.)
 | ||
| ```
 | ||
| 
 | ||
| ---
 | ||
| 
 | ||
| ## 2) Runtime Shape
 | ||
| 
 | ||
| **Process**: single service (`StellaOps.Feedser.WebService`)
 | ||
| 
 | ||
| * `Program.cs`: top-level entry using **Generic Host**, **DI**, **Options** binding from `appsettings.json` + environment + optional `feedser.yaml`.
 | ||
| * Built-in **scheduler** (cron-like) + **job manager** with **distributed locks** in Mongo to prevent overlaps, enforce timeouts, allow cancel/kill.
 | ||
| * **REST APIs** for health/readiness/progress/trigger/kill/status.
 | ||
| 
 | ||
| **Key NuGet concepts** (indicative): `MongoDB.Driver`, `Polly` (retry/backoff), `System.Threading.Channels`, `Microsoft.Extensions.Http`, `Microsoft.Extensions.Hosting`, `Serilog`, `OpenTelemetry`.
 | ||
| 
 | ||
| ---
 | ||
| 
 | ||
| ## 3) Data Storage — **MongoDB** (single source of truth)
 | ||
| 
 | ||
| **Database**: `feedser`
 | ||
| **Write concern**: `majority` for merge/export state, `acknowledged` for raw docs.
 | ||
| **Collections** (with “flags”/resume points):
 | ||
| 
 | ||
| * `source`
 | ||
|   * `_id`, `name`, `type`, `baseUrl`, `auth`, `notes`.
 | ||
| * `source_state`
 | ||
|   * Keys: `sourceName` (unique), `enabled`, `cursor`, `lastSuccess`, `failCount`, `backoffUntil`, `paceOverrides`, `paused`.
 | ||
|   * Drives incremental fetch/parse/map resume and operator pause/pace controls.
 | ||
| * `document`
 | ||
|   * `_id`, `sourceName`, `uri`, `fetchedAt`, `sha256`, `contentType`, `status`, `metadata`, `gridFsId`, `etag`, `lastModified`.
 | ||
|   * Index `{sourceName:1, uri:1}` unique; optional TTL for superseded versions.
 | ||
| * `dto`
 | ||
|   * `_id`, `sourceName`, `documentId`, `schemaVer`, `payload` (BSON), `validatedAt`.
 | ||
|   * Index `{sourceName:1, documentId:1}`.
 | ||
| * `advisory`
 | ||
|   * `_id`, `advisoryKey`, `title`, `summary`, `lang`, `published`, `modified`, `severity`, `exploitKnown`.
 | ||
|   * Unique `{advisoryKey:1}` plus indexes on `modified` and `published`.
 | ||
| * `alias`
 | ||
|   * `advisoryId`, `scheme`, `value` with index `{scheme:1, value:1}`.
 | ||
| * `affected`
 | ||
|   * `advisoryId`, `platform`, `name`, `versionRange`, `cpe`, `purl`, `fixedBy`, `introducedVersion`.
 | ||
|   * Index `{platform:1, name:1}`, `{advisoryId:1}`.
 | ||
| * `reference`
 | ||
|   * `advisoryId`, `url`, `kind`, `sourceTag` (e.g., advisory/patch/kb).
 | ||
| * Flags collections: `kev_flag`, `ru_flags`, `jp_flags`, `psirt_flags` keyed by `advisoryId`.
 | ||
| * `merge_event`
 | ||
|   * `_id`, `advisoryKey`, `beforeHash`, `afterHash`, `mergedAt`, `inputs` (document ids).
 | ||
| * `export_state`
 | ||
|   * `_id` (`json`/`trivydb`), `baseExportId`, `baseDigest`, `lastFullDigest`, `lastDeltaDigest`, `exportCursor`, `targetRepo`, `exporterVersion`.
 | ||
| * `locks`
 | ||
|   * `_id` (`jobKey`), `holder`, `acquiredAt`, `heartbeatAt`, `leaseMs`, `ttlAt` (TTL index cleans dead locks).
 | ||
| * `jobs`
 | ||
|   * `_id`, `type`, `args`, `state`, `startedAt`, `endedAt`, `error`, `owner`, `heartbeatAt`, `timeoutMs`.
 | ||
| 
 | ||
| **GridFS buckets**: `fs.documents` for raw large payloads; referenced by `document.gridFsId`.
 | ||
| 
 | ||
| ---
 | ||
| 
 | ||
| ## 4) Job & Scheduler Model
 | ||
| 
 | ||
| * Scheduler stores cron expressions per source/exporter in config; persists next-run pointers in Mongo.
 | ||
| * Jobs acquire locks (`locks` collection) to ensure singleton execution per source/exporter.
 | ||
| * Supports manual triggers via API endpoints (`POST /jobs/{type}`) and pause/resume toggles per source.
 | ||
| 
 | ||
| ---
 | ||
| 
 | ||
| ## 5) Connector Contracts
 | ||
| 
 | ||
| Connectors implement:
 | ||
| 
 | ||
| ```csharp
 | ||
| public interface IFeedConnector {
 | ||
|     string SourceName { get; }
 | ||
|     Task FetchAsync(IServiceProvider sp, CancellationToken ct);
 | ||
|     Task ParseAsync(IServiceProvider sp, CancellationToken ct);
 | ||
|     Task MapAsync(IServiceProvider sp, CancellationToken ct);
 | ||
| }
 | ||
| ```
 | ||
| 
 | ||
| * Fetch populates `document` rows respecting rate limits, conditional GET, and `source_state.cursor`.
 | ||
| * Parse validates schema (JSON Schema, XSD) and writes sanitized DTO payloads.
 | ||
| * Map produces canonical advisory rows + provenance entries; must be idempotent.
 | ||
| * Base helpers in `StellaOps.Feedser.Source.Common` provide HTTP clients, retry policies, and watermark utilities.
 | ||
| 
 | ||
| ---
 | ||
| 
 | ||
| ## 6) Merge & Normalization
 | ||
| 
 | ||
| * Canonical model stored in `StellaOps.Feedser.Models` with serialization contracts used by storage/export layers.
 | ||
| * `StellaOps.Feedser.Normalization` handles NEVRA/EVR/PURL range parsing, CVSS normalization, localization.
 | ||
| * `StellaOps.Feedser.Merge` builds alias graphs keyed by CVE first, then falls back to vendor/regional IDs.
 | ||
| * Precedence rules: PSIRT/OVAL overrides generic ranges; KEV only toggles exploitation; regional feeds enrich severity but don’t override vendor truth.
 | ||
| * Determinism enforced via canonical JSON hashing logged in `merge_event`.
 | ||
| 
 | ||
| ---
 | ||
| 
 | ||
| ## 7) Exporters
 | ||
| 
 | ||
| * JSON exporter mirrors `aquasecurity/vuln-list` layout with deterministic ordering and reproducible timestamps.
 | ||
| * Trivy DB exporter initially shells out to `trivy-db` builder; later will emit BoltDB directly.
 | ||
| * `StellaOps.Feedser.Storage.Mongo` provides cursors for delta exports based on `export_state.exportCursor`.
 | ||
| * Export jobs produce OCI tarballs (layer media type `application/vnd.aquasec.trivy.db.layer.v1.tar+gzip`) and optionally push via ORAS.
 | ||
| 
 | ||
| ---
 | ||
| 
 | ||
| ## 8) Observability
 | ||
| 
 | ||
| * Serilog structured logging with enrichment fields (`source`, `uri`, `stage`, `durationMs`).
 | ||
| * OpenTelemetry traces around fetch/parse/map/export; metrics for rate limit hits, schema failures, dedupe ratios, package size.
 | ||
| * Prometheus scraping endpoint served by WebService.
 | ||
| 
 | ||
| ---
 | ||
| 
 | ||
| ## 9) Security Considerations
 | ||
| 
 | ||
| * Offline-first: connectors only reach allowlisted hosts.
 | ||
| * BDU LLM fallback gated by config flag; logs audit trail with confidence score.
 | ||
| * No secrets written to logs; secrets loaded via environment or mounted files.
 | ||
| * Signing handled outside Feedser pipeline.
 | ||
| 
 | ||
| ---
 | ||
| 
 | ||
| ## 10) Deployment Notes
 | ||
| 
 | ||
| * Default storage MongoDB; for air-gapped, bundle Mongo image + seeded data backup.
 | ||
| * Horizontal scale achieved via multiple web service instances sharing Mongo locks.
 | ||
| * Provide `feedser.yaml` template describing sources, rate limits, and export settings.
 |