Mondial Backend

Production .NET 8 backend for the Mondial SaaS — stateless, horizontally scalable, Docker-deployed, MongoDB + Redis backed.

Stack

Runtime	.NET 8 (ASP.NET Core)
Data	MongoDB Atlas
Cache / SignalR backplane / presence / DataProtection keys	Redis
Auth	ASP.NET Identity + JWT bearer (HS256, 30s clock skew)
Real-time	SignalR with Redis backplane
Observability	Serilog (correlation-id enriched) + OpenTelemetry traces/metrics + Prometheus scrape at /metrics
Deploy	Docker on a VPS behind Traefik (Let's Encrypt TLS), GHCR-pushed images, GitHub Actions CD

Architecture (high level)

Internet ─► Traefik (TLS, HTTP→HTTPS, /metrics IP-allowlist, LB w/ /health/ready probe)
            │
            ├─► api replica 1  ┐
            ├─► api replica 2  ├─► Redis  (backplane / cache / presence / DP keys)
            └─► api replica N  ┘
                       │
                       └─► MongoDB Atlas

Stateless replicas — scale with docker compose up -d --scale api=N.

Documentation

File	Purpose
DEPLOYMENT.md	One-time VPS setup, first deploy, scaling, rollback
OPERATIONS.md	SLOs, incident playbook, backup/recovery, alerts
LAUNCH.md	Pre-launch go/no-go checklist + load test
CHANGELOG.md	Phase-by-phase history of the hardening track
appsettings.Example.json	Required configuration keys (env-var driven)
ops/prometheus-alerts.yml	Prometheus alerting rules

Configuration

The app refuses to start without required secrets (StartupConfigValidation). Supply them via:

• Dev: dotnet user-secrets set "<Section:Key>" "..." (per appsettings.Example.json).
• Prod: environment variables in /opt/mondial/.env (Section__Key form), chmod 600.

Never commit real secrets. appsettings.json ships with empty placeholders.

Build / test / run

dotnet restore WebApp.sln
dotnet build   WebApp.sln -c Release
dotnet test    WebApp.sln -c Release        # 12 unit tests
# Integration tests use Testcontainers (Mongo+Redis) — run automatically
# in CI; locally they SkippableFact-skip without Docker.

Local run requires user-secrets set + a reachable Redis + MongoDB.

Runtime smoke test (no external infra)

pwsh scripts/smoke-local.ps1                 # Mode=Run  - dotnet build + WebApp.dll, Development
pwsh scripts/smoke-local.ps1 -Mode Published # dotnet publish + WebApp.dll, Production
                                             #   (the exact execution path the Docker container uses)

Boots the app with format-valid dummy config and probes the public surface end-to-end (health, /version, /.well-known/security.txt, /metrics, security headers, correlation-id, response compression, 404 handling, per-IP rate limit). Requires no external Mongo/Redis; 9 probes pass in either mode.

Deploy

See DEPLOYMENT.md. CI builds + tests on every push; CD builds an image on main, pushes to GHCR, and SSH-deploys to the VPS via .github/workflows/deploy.yml.

Security

• All secrets env/user-secrets driven; none in tracked files.
• Per-IP rate limiting (auth: 5/min/IP; global: 100/min/IP).
• Security headers (CSP, X-Frame-Options DENY, nosniff, Referrer-Policy, Permissions-Policy) + HSTS in prod.
• ForwardedHeaders trusted only from known networks/proxies (anti-spoof).
• JWT clock skew 30s, ASP.NET Identity password policy.
• FluentValidation on all auth inputs; envelope-consistent 400s.
• Audit log on every credential lifecycle event.
• Vulnerability gate in CI (dotnet list package --vulnerable).
• /.well-known/security.txt for responsible disclosure.

Observability

Every response carries X-Correlation-ID; every log line is tagged with it. Filter logs / traces / audits by that id to follow a single user request.