# Architecture diagrams Visual cross-cuts of `apf_portal`'s architecture. Each diagram summarises decisions that are spread across several ADRs and exists to help a contributor (or auditor, RSSI, IT contact) build a mental model fast. Decisions themselves live in [decisions/](decisions/); diagrams reflect the current accepted state. Diagrams are written in [Mermaid](https://mermaid.js.org/) — text in markdown, rendered natively by Gitea, GitHub, and most IDE markdown viewers. Updating a diagram is an ordinary text edit reviewable in PR. When a diagram is the _content_ of a single decision (e.g. a sequence diagram that captures a flow described by one ADR), it lives **inside that ADR**, not here. This file holds the _cross-cutting_ views. --- ## 1. System context (C4 level 1) The portal as a black box, with the actors that interact with it and the external systems it depends on. Sources: [ADR-0008](decisions/0008-identity-model-entra-workforce-dual-audience.md) (identity model), [ADR-0014](decisions/0014-downstream-api-access-obo-pattern.md) (downstream APIs), [ADR-0013](decisions/0013-audit-trail-separated-postgres-append-only.md) (audit access). ```mermaid flowchart TB workforce([Workforce user
employee]) customer([Customer user
external
future]) it([IT / Identity admin]) rssi([RSSI / SOC analyst]) portal[apf_portal
web portal centralising
access to existing apps] entra[(Microsoft Entra ID
workforce tenant
+ M365 Developer dev tenant)] extid[(Microsoft Entra External ID
customer tenant
future)] downstream[(Downstream APIs
existing applications
integrated by the portal)] workforce -->|browser HTTPS| portal customer -.->|browser HTTPS
future| portal portal -->|OIDC Auth Code + PKCE| entra portal -.->|OIDC Auth Code + PKCE
future| extid portal -->|OBO or signed assertion| downstream it -->|configures
tenant + Conditional Access
+ B2B invitations| entra rssi -->|reads audit events
via audit_reader role| portal classDef future stroke-dasharray: 5 5,opacity:0.7 class customer,extid future ``` Dashed = future scope (not v1). The customer audience is _designed for_ but not implemented (per the dual-audience design in ADR-0008); it is shown to make the future expansion legible. --- ## 2. Containers (C4 level 2) The runtime artefacts and their conversations. One step deeper than system context: what is actually deployed. Sources: [ADR-0002](decisions/0002-adopt-nx-monorepo-apps-preset.md) (Nx layout), [ADR-0004](decisions/0004-frontend-stack-angular-csr-zoneless-signals.md) (Angular SPA), [ADR-0005](decisions/0005-backend-stack-nestjs.md) (NestJS BFF), [ADR-0006](decisions/0006-persistence-postgresql-prisma.md) (Postgres + Prisma), [ADR-0009](decisions/0009-auth-flow-oidc-pkce-msal-node.md) (auth flow), [ADR-0010](decisions/0010-session-management-redis.md) (sessions in Redis), [ADR-0012](decisions/0012-observability-pino-opentelemetry.md) (OTel collector), [ADR-0014](decisions/0014-downstream-api-access-obo-pattern.md) (downstream calls), [ADR-0020](decisions/0020-portal-admin-app.md) (admin SPA). ```mermaid flowchart TB user([Workforce user]) admin([Admin user
role:admin]) subgraph Browser["Browser"] spa["portal-shell
Angular 21 SPA
zoneless / Signals / Tailwind 4"] spaAdmin["portal-admin
Angular 21 SPA
distinct origin / bundle"] end subgraph OnPrem["On-prem deployment"] bff["portal-bff
NestJS 11 / Node 24
Express adapter
· /api/* (end-user)
· /api/admin/* (RBAC + @RequireMfa)"] pg[("Postgres 17
schemas: public + audit
RLS for dual-audience")] redis[("Redis
sessions + OBO token cache
AES-256-GCM at rest")] otel["OTel Collector
local sidecar
(OTLP → backend, future)"] end entra[(Microsoft Entra ID)] downstream[(Downstream APIs)] user -->|HTTPS| spa admin -->|HTTPS| spaAdmin spa -->|"HTTPS
__Host-portal_session
X-CSRF-Token
traceparent"| bff spaAdmin -->|"HTTPS
distinct session cookie
(separate sign-in flow,
fresh-MFA enforced)
traceparent"| bff spa -. "OTLP / HTTP
(browser spans)" .-> otel spaAdmin -. "OTLP / HTTP
(browser spans)" .-> otel bff -->|"OIDC Auth Code + PKCE
via @azure/msal-node"| entra bff -->|Prisma 7| pg bff -->|"ioredis
(opaque session id
→ encrypted blob)"| redis bff -->|"OBO token (Entra-protected)
or signed X-User-Assertion JWT
+ traceparent"| downstream bff -. "OTLP / HTTP
(server spans + Pino logs)" .-> otel ``` Notes embedded in the diagram: - **Two SPAs, one BFF.** `portal-shell` is the end-user surface; `portal-admin` is a separate Angular app on a distinct origin with its own bundle, sign-in flow, and session cookie (per ADR-0020). They share libs but never a runtime — an admin session is not silently authenticated to `portal-shell` and vice versa. The admin entry route is gated by an Entra `Portal.Admin` app-role claim + `@RequireMfa({ freshness: 600 })` per ADR-0011. - The SPAs carry no token. Only the opaque session id cookie (`__Host-portal_session` / `__Host-portal_admin_session`) plus the CSRF cookie (`__Host-portal_csrf`, read by JS for double-submit). - `traceparent` (W3C) propagates from the browser through the BFF to the downstream APIs — same `trace_id` end-to-end. - The OTel Collector is the only piece coupled to the eventual on-prem observability backend. Choice of backend (Grafana Loki + Tempo, ELK, …) is deferred to the on-prem infrastructure ADR. --- ## 3. Nx module boundaries Which projects are allowed to depend on which. Encoded in `eslint.config.mjs` via `@nx/enforce-module-boundaries` with the `depConstraints` from [ADR-0003](decisions/0003-workspace-and-app-naming-convention.md). Each project carries two tags: - **`scope:`** — `portal-shell`, `portal-bff`, or `shared` (for libs consumable by both apps). - **`type:`** — `app`, `feature`, or `shared`. A dependency is allowed only if both axes permit it. ```mermaid flowchart LR subgraph Apps["apps · type:app"] shell["portal-shell
scope:portal-shell"] admin["portal-admin
scope:portal-admin"] bff["portal-bff
scope:portal-bff"] end subgraph FeatureLibs["libs · type:feature"] fauth["feature-auth
scope:portal-shell"] end subgraph SharedAnyLibs["libs · type:shared · scope:shared"] sui["shared-ui
Angular components
(spartan-style on CDK)"] sstate["shared-state
cross-surface signals
(LayoutStateService, ...)"] stokens["shared-tokens
design tokens (a11y)"] sutil["shared-util
cross-runtime TS helpers"] end shell --> fauth shell --> sui shell --> sstate shell --> stokens shell --> sutil admin -. "future" .-> sui admin -. "future" .-> sstate admin -. "future" .-> stokens admin -. "future" .-> sutil bff --> stokens bff --> sutil fauth --> sui fauth --> stokens fauth --> sutil sui --> stokens classDef forbidden stroke:#c00,stroke-dasharray: 4 4 ``` Notes: - `portal-admin` is a v1 skeleton (per ADR-0020) — it currently imports no libs. Its planned dependencies on the `scope:shared` set are drawn dashed; they materialise as the admin modules land. No `scope:portal-admin` row exists in `eslint.config.mjs` yet; one lands when the admin modules grow real lib dependencies (follow-up). - Every Angular-flavoured shared lib (`shared-ui`, `shared-state`) lives under `scope:shared`, not `scope:portal-shell`. The naming was historically ambiguous; what matters is the tag in `project.json`, which gates lint-time enforcement. Forbidden by the depConstraints (and lint-enforced) — examples: - `portal-bff` ⟶ `shared-ui` / `feature-auth` (`scope:portal-bff` may only reach `scope:portal-bff` + `scope:shared`; and the BFF runs in Node anyway, so Angular code is mechanically unusable). - `portal-shell` ⟶ `portal-admin` (cross-app — apps don't reach into each other; they communicate via the BFF). - `shared-tokens` ⟶ `feature-auth` (`type:shared` may only reach `type:shared`, so feature libs are off-limits). - Any lib ⟶ any app. --- ## 4. CI/CD pipeline How a change moves from a developer's keyboard to `main`. Reflects [ADR-0007](decisions/0007-pre-commit-hooks-and-conventional-commits.md) (local hooks), [ADR-0015](decisions/0015-cicd-gitea-actions.md) (Gitea Actions, trunk-based + squash-merge), [ADR-0016](decisions/0016-accessibility-baseline-wcag-aa-targeted-aaa.md) (a11y gate), [ADR-0017](decisions/0017-performance-budgets-lighthouse-ci.md) (perf gate). ```mermaid flowchart TB edit[Edit on feat/*, fix/*, chore/*, docs/* branch] pre[".husky/pre-commit
lint-staged → prettier on staged"] msg[".husky/commit-msg
commitlint → Conventional Commits"] push[git push origin feat/*] pr[Open PR → main] subgraph PRJobs["CI on PR · .gitea/workflows/ci.yml · all blocking"] direction LR j1["check
nx affected -t
format / lint / test / build"] j2["scan
pnpm audit + Trivy + gitleaks"] j3["commits
commitlint on PR range"] j4["perf
Lighthouse CI
CWV thresholds (ADR-0017)"] j5["a11y
axe-core via Playwright
(placeholder until first screens)"] end protection{"Branch protection on main
· all 5 jobs green
· ≥0 reviewers (v1, →≥1 with 2nd contributor)
· linear history
· no direct push, no force push"} squash["Squash-merge
subject = Conventional Commits
(becomes the commit on main)"] tag[Tag vX.Y.Z] release[".gitea/workflows/release.yml
(stub today, populated with on-prem deploy ADR)"] edit --> pre --> msg --> push --> pr pr --> PRJobs --> protection -->|all green| squash --> tag --> release cron["Weekly cron · Mon 04:00 UTC"] sched[".gitea/workflows/security-scheduled.yml
full-tree Trivy + gitleaks
+ Lighthouse on prod (when LHCI_PROD_URL set)"] cron --> sched ``` Note the parallelism: the five PR jobs run **in parallel**. The diagram shows the gate as one square because branch protection requires _all five_ before squash-merge is allowed. --- ## 5. Local dev infrastructure What `docker compose up` actually starts when you run the project locally. The aim is to make the runtime dependencies visible at a glance — services, ports, named volumes, optional profiles, and how they relate to the dev-loop tools (Jaeger, pgweb, Caddy). Sources: [infra/local/dev.compose.yml](../infra/local/dev.compose.yml), [infra/ci-runners.compose.yml](../infra/ci-runners.compose.yml), [ADR-0006](decisions/0006-persistence-postgresql-prisma.md) (Postgres), [ADR-0010](decisions/0010-session-management-redis.md) (Redis dev mode), [ADR-0012](decisions/0012-observability-pino-opentelemetry.md) (OTel Collector), [ADR-0015](decisions/0015-cicd-gitea-actions.md) (CI runners), [ADR-0019](decisions/0019-internationalisation-angular-localize.md) (Caddy locale routing). ```mermaid flowchart TB subgraph Host["Developer host"] direction TB subgraph DevStack["docker compose · name: apf-portal-dev · network: apf-portal-dev"] direction TB subgraph AlwaysUp["Always up"] direction LR pg["postgres
image: postgres:17.2-alpine
host port 5432
POSTGRES_USER / _PASSWORD / _DB
bootstrap SQL from init/postgres/"] redis["redis
image: redis:7.4-alpine
host port 6379
--requirepass + --appendonly yes"] otel["otel-collector
image: otel/opentelemetry-collector-contrib:0.150.1
OTLP gRPC 4317 / HTTP 4318
config: otel-collector.yaml"] end subgraph ProfileDbtools["profile: dbtools"] direction LR pgweb["pgweb
image: sosedoff/pgweb:0.16.2
host port 8081"] end subgraph ProfileObs["profile: observability"] direction LR jaeger["jaeger
image: jaegertracing/jaeger:2.17.0
UI host port 16686
OTLP receiver internal only"] end subgraph ProfileServeStatic["profile: serve-static"] direction LR caddy["serve-static (Caddy)
image: caddy:2.10-alpine
host port 4200
serves dist/apps/portal-shell/browser
(per-locale routing per ADR-0019)"] end vols[("Named volumes
apf-portal-postgres-data
apf-portal-redis-data")] end subgraph CIStack["docker compose · name: apf-portal-ci-runners · network: act-runners"] direction LR r1["runner-1
gitea/act_runner:0.2.13
labels: self-hosted, on-prem
image: catthehacker/ubuntu:act-22.04"] r2["runner-2
(same image / config)"] r3["runner-3
(same image / config)"] end bffProc["portal-bff
local Node process
(pnpm nx serve portal-bff)
port 3000"] spaProc["portal-shell
Angular dev server
(pnpm nx serve portal-shell)
port 4200"] end pg -. "AOF / data" .-> vols redis -. "AOF / data" .-> vols pgweb --> pg otel -. "forward" .-> jaeger caddy -. "reads
dist bind-mount" .-> caddy bffProc -->|DATABASE_URL| pg bffProc -->|REDIS_URL| redis bffProc -. "OTLP HTTP" .-> otel spaProc -. "OTLP HTTP
browser spans" .-> otel spaProc -->|"fetch /api/*"| bffProc classDef profile fill:#f6f8fa,stroke:#bbb,stroke-dasharray: 3 3 class ProfileDbtools,ProfileObs,ProfileServeStatic profile ``` Bring-up cheat sheet: ```bash # Always-up services only (postgres + redis + otel-collector). docker compose -f infra/local/dev.compose.yml up -d # With viewers (pgweb at :8081, Jaeger at :16686). docker compose -f infra/local/dev.compose.yml \ --profile dbtools --profile observability up -d # Plus the production-like static server (Caddy at :4200). # Use after `pnpm exec nx build portal-shell --configuration=production`. docker compose -f infra/local/dev.compose.yml --profile serve-static up -d # Wipe state (recreates the bootstrap SQL on next up). docker compose -f infra/local/dev.compose.yml down -v ``` Notes: - **The BFF and SPA themselves are not in compose.** They run as local Node / Angular dev-server processes via `pnpm nx serve …`. Compose only hosts the runtime _dependencies_ — keeping the inner-loop edit/refresh fast. The Caddy `serve-static` profile is the production-shape exception: it lets you eyeball a prod build under the locale routing without standing up a real reverse proxy. - **Named volumes are intentional.** Wiping `down -v` is the supported reset path; the Postgres bootstrap SQL (audit schema + role grants per ADR-0013) only runs on a fresh data volume. - **The CI runners stack is separate** (`infra/ci-runners.compose.yml`, `name: apf-portal-ci-runners`) and lives on its own Docker network. Same host machine in v1, but co-located by convenience, not by coupling — they can move to a different host without touching the dev stack. The runners register with Gitea via `GITEA_RUNNER_REGISTRATION_TOKEN` on first boot and persist their credentials in `./data/runner-N/`. - **Ports listed are the host-side defaults.** All can be overridden through `infra/local/.env` (`POSTGRES_PORT`, `REDIS_PORT`, `OTEL_HTTP_PORT`, `JAEGER_UI_PORT`, `SERVE_STATIC_PORT`, …). The container-side ports never change. --- ## To be added As features land, the following diagrams will be added — either here, or inline in the ADR they belong to (per the convention stated at the top: _cross-cutting → here, single-decision → in the ADR_). | Diagram | Where it will land | Triggered by | | ------------------------------------------------------------------------------------------ | ---------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------- | | **OIDC Auth Code + PKCE sequence** | inline in [ADR-0009](decisions/0009-auth-flow-oidc-pkce-msal-node.md) | already useful — added at the same time as this file | | **Trace context propagation** (SPA → BFF → DB → downstream) | here | trigger met — observability is wired end-to-end; diagram pending a follow-up PR | | **Dual-audience flow** (token validation, claim → enum, RLS filtering) | here or split between ADRs 0008/0009/0013 | first authz code that touches the audience | | **Step-up MFA flow** (claims challenge round-trip) | inline in [ADR-0011](decisions/0011-mfa-enforcement-entra-conditional-access.md) | first `@RequireMfa()` route | | **Database ERD** | inline in [ADR-0006](decisions/0006-persistence-postgresql-prisma.md) or a dedicated `data.md` | first business model in `schema.prisma` | | **Audit event lifecycle** (writer → store → archiver → reader) | inline in [ADR-0013](decisions/0013-audit-trail-separated-postgres-append-only.md) | audit module shipped | | **Downstream call lifecycle** (audience pre-check → strategy → cache → resilience → trace) | inline in [ADR-0014](decisions/0014-downstream-api-access-obo-pattern.md) | first downstream integration | | **Trust boundaries** (security review view) | here | when the RSSI requests a security architecture review |