System Overview

Last Updated: 2026-04-25

High-Level Architecture

Porta is a multi-tenant OIDC identity provider built on Koa + node-oidc-provider + TypeScript. It serves as a complete authentication and user management platform with organization-scoped tenancy, RBAC, custom claims, and two-factor authentication.

Component Overview

Core Runtime

Component	Technology	Purpose
HTTP Server	Koa 2.x	Request handling, middleware pipeline
OIDC Engine	node-oidc-provider 9.x	OpenID Connect protocol implementation
Database	PostgreSQL 16 (pg)	Persistent storage, long-lived OIDC artifacts
Cache/Sessions	Redis 7 (ioredis)	Short-lived OIDC artifacts, tenant cache, rate limits
Logger	pino	Structured logging (JSON in prod, pretty in dev)
Config	zod	Environment validation with fail-fast semantics
Signing	jose + crypto	ES256 (ECDSA P-256) token signing
CLI	yargs	Admin command-line interface
Admin GUI SPA	React 19 + FluentUI v9	Browser-based admin dashboard
Admin GUI BFF	Koa (separate process)	Backend-for-frontend: OIDC auth, session, API proxy
Admin GUI Build	Vite	SPA bundler and dev server

Domain Modules

Porta follows a modular domain architecture where each business domain is encapsulated in its own directory under src/:

Module	Directory	Responsibility
Organizations	src/organizations/	Tenant management, status lifecycle, branding
Applications	src/applications/	SaaS product definitions, module grouping
Clients	src/clients/	OIDC client registration, secret management
Users	src/users/	User accounts, passwords, status lifecycle
Auth	src/auth/	Authentication workflows, magic links, email, templates
RBAC	src/rbac/	Roles, permissions, user-role assignments
Custom Claims	src/custom-claims/	Claim definitions, user claim values
Two-Factor	src/two-factor/	TOTP, email OTP, recovery codes
CLI	src/cli/	Admin CLI with dual-mode bootstrap

Each domain module follows a consistent internal structure:

src/<module>/
├── index.ts          # Barrel export (public API)
├── types.ts          # Domain types, interfaces, row mapping
├── errors.ts         # Domain-specific error classes
├── repository.ts     # PostgreSQL CRUD operations
├── cache.ts          # Redis caching layer
├── service.ts        # Business logic, validation, orchestration
├── slugs.ts          # Slug generation and validation (where applicable)
└── validators.ts     # Input validation (where applicable)

Admin GUI Module

The Admin GUI is a separate application in admin-gui/ with its own package.json, build pipeline, and test suite. It consists of two layers:

Layer	Technology	Purpose
React SPA (admin-gui/src/client/)	React 19, FluentUI v9, React Router, React Query	Browser-based admin dashboard
Koa BFF (admin-gui/src/server/)	Koa, koa-session, ioredis	OIDC auth, session management, CSRF, API proxy

The SPA communicates exclusively through the BFF — it never talks to the Porta Admin API directly. The BFF handles Bearer token injection, OIDC token refresh, and security concerns (CSRF, session cookies).

SPA Architecture:

admin-gui/src/client/
├── api/             # Typed API client + 13 React Query domain hook modules
├── components/      # 27 reusable UI components (EntityDataGrid, StatusBadge, etc.)
├── hooks/           # 8 hooks (useAuth, useOrgContext, useTheme, etc.)
├── layouts/         # AppShell, Sidebar, TopBar, Breadcrumbs
├── pages/           # Route page components (Dashboard, Orgs, Apps, Users, etc.)
├── router.tsx       # React Router with breadcrumb-enabled routes
└── types.ts         # Shared client-side type definitions

Application Startup Sequence

The application starts via src/index.ts in a strict 7-step sequence:

Fail-fast principle: If any startup step fails (DB connection, Redis connection, config validation), the process logs a fatal error and calls process.exit(1).

Middleware Stack

The Koa middleware stack is assembled in src/server.ts in this precise order:

Key Middleware Details

Middleware	File	Purpose
Error Handler	error-handler.ts	Global try/catch, hides internal details for 5xx
Request Logger	request-logger.ts	UUID request ID, logs method/url/status/duration
Security Headers	security-headers.ts	CSP default-src 'none', X-Frame-Options, HSTS, etc.
Metrics	metrics.ts	Prometheus metrics at GET /metrics (optional)
Root Page	root-page.ts	Neutral /, /robots.txt, /favicon.ico (no product leakage)
Health Check	health.ts	DB + Redis connectivity check at /health
Readiness	ready.ts	Readiness probe for container orchestration
Admin Auth	admin-auth.ts	JWT Bearer validation for /api/admin/* routes
Admin CORS	admin-cors.ts	CORS handling for /api/admin/* (configurable origins)
Admin Rate Limiter	admin-rate-limiter.ts	Rate limiting for admin API endpoints
Require Permission	require-permission.ts	Granular RBAC permission checks for admin routes
Token Rate Limiter	token-rate-limiter.ts	Rate limiting for token endpoints
Tenant Resolver	tenant-resolver.ts	Cache-first org lookup from URL slug
Client Secret Hash	client-secret-hash.ts	SHA-256 pre-hash for client_secret_post
OIDC CORS	oidc-cors.ts	CORS handling for OIDC endpoints

Multi-Tenancy Model

Porta uses path-based multi-tenancy where each organization gets its own OIDC issuer URL:

https://auth.example.com/{orgSlug}/.well-known/openid-configuration
https://auth.example.com/{orgSlug}/auth
https://auth.example.com/{orgSlug}/token

The tenant resolver middleware (src/middleware/tenant-resolver.ts) uses a cache-first strategy:

1. Check Redis cache for org by slug
2. On miss → query PostgreSQL
3. Cache the result in Redis
4. Set ctx.state.organization for downstream handlers
5. Return appropriate HTTP status based on org status:
   • active → proceed
   • suspended → 403
   • archived → 410
   • Not found → pass through (no match)

Graceful Shutdown

On SIGTERM or SIGINT:

1. Stop accepting new connections
2. Close the HTTP server
3. Disconnect Redis
4. Close the PostgreSQL pool
5. Force exit after 10 seconds if still hanging

Related Documentation

• Data Model — Database schema and entity relationships
• API Design — REST conventions and endpoint structure
• Security — Authentication, crypto, and isolation
• Configuration Reference — All environment variables
• Admin GUI Guide — Product documentation for the Admin GUI