julien
758d723744
## Summary
Mounts `express-session` + `connect-redis` at bootstrap on top of the shared `ioredis` client, with **AES-256-GCM applied to the full JSON payload before it lands in Redis** (per ADR-0010). The configured middleware is exposed as a NestJS provider (`SESSION_MIDDLEWARE`) and `main.ts` mounts it through `app.get(...)` so it sits on the same Redis connection the rest of the BFF uses — no second client at the bootstrap layer.
Envelope is versioned (`v1.<iv>.<tag>.<ciphertext>`, all base64url) so the algorithm / key derivation can rotate without a flag-day re-encryption. Tamper / wrong-key / unknown-version all raise `SessionDecryptError`; for now the failure is logged via Pino with `event: session.decrypt_failed` — the first-class audit event lands with ADR-0013.
Scope is intentionally **infrastructure only**:
- middleware mounted on every request, `req.session` available downstream
- session id = `crypto.randomBytes(32).toString('base64url')` (256 bits per ADR-0010)
- cookie name: `__Host-portal_session` in production, `portal_session` in dev (the `__Host-` prefix mandates `Secure`, which dev HTTP can't satisfy)
- `httpOnly + sameSite=lax + path=/`; `resave:false`, `saveUninitialized:false`, `rolling:true`
- cookie `maxAge` follows `SESSION_IDLE_TIMEOUT_SECONDS` (default 1800)
- encryption-at-rest active end-to-end
Out of scope, landing in follow-ups: `/auth/callback` populating `req.session.user`, `/me`, `/auth/logout`, the absolute-timeout interceptor, and the `user_sessions:{userId}` secondary index.
## Notable shape choices (ADR-0010 amended in the same commit)
**Full-payload encryption vs. just the `tokens` field.** The first draft of ADR-0010 scoped at-rest encryption to a `tokens` sub-field. The session also carries claims (`oid`, `tid`, `preferred_username`, …) that qualify as PII under GDPR — for an APF-Handicap portal handling health-adjacent data this matters. Encrypting the envelope is strictly stronger and removes the need to classify fields one by one. The ADR text is updated to match.
**`ioredis` + adapter vs. switching the BFF to `node-redis`.** `connect-redis` v9 was rewritten for `node-redis` v4 and no longer accepts `ioredis` directly. Two reasonable paths:
1. **Adapter (chosen)** — keep the shared `ioredis` client; shim the six commands `connect-redis` actually calls (`get`, `set` with `{expiration:{type:'EX',value}}`, `expire`, `del`, `mGet`, `scanIterator`) to the node-redis shape. Smallest blast radius — RedisModule, OBO cache (ADR-0014), future pub/sub all stay on a single Redis library.
2. **Switch RedisModule to `node-redis`** — clean alignment with `connect-redis`'s expectations, but touches every Redis consumer and would itself require an ADR amendment.
The adapter is reversible: if we ever decide to standardise on `node-redis`, deleting one file removes it. Happy to switch if you'd rather take that path.
## Env vars
- `SESSION_ENCRYPTION_KEY` — **mandatory**, AES-256-GCM key (32 bytes after base64url decode). New `assertSessionEncryptionKey()` validator wired in `main.ts` alongside the other pre-flight checks.
- `SESSION_IDLE_TIMEOUT_SECONDS` — optional, default `1800`.
- `SESSION_ABSOLUTE_TIMEOUT_SECONDS` — optional, default `43200` (consumed by the absolute-timeout interceptor in a follow-up).
`.env.example` updated; the three variables are promoted from the "future vars" block to the active section.
## Test plan
- [x] `pnpm nx test portal-bff` — **99/99 pass** (was 62 before this PR; +37 new specs across the 5 new files).
- [x] `pnpm nx build portal-bff` — clean webpack build.
- [x] `pnpm nx lint portal-bff` — clean.
- [x] Prettier-clean for all PR source files.
- [ ] Local smoke test once the next PR wires `/auth/callback` → `req.session.user`; this PR has no user-visible behaviour to exercise on its own.
---------
Co-authored-by: Julien Gautier <julien.gautier@apf.asso.fr>
Reviewed-on: #110
Architectural Decision Records
This project records architecturally-significant decisions as ADRs in the MADR 4.0.0 format. References: adr.github.io.
Why ADRs
ADRs capture the why behind a decision — context, drivers, options considered, trade-offs accepted — at the moment the decision is made. They make architecture reviewable, onboarding faster, and prevent the same debate from being re-litigated later.
Conventions
- Format: MADR 4.0.0. Start from template.md.
- Filename:
NNNN-kebab-case-title.md, e.g.0007-adopt-tailwind-for-design-tokens.md. - Numbering: globally sequential 4-digit prefix. Numbers never reset, never get reused — even when an ADR is superseded or deprecated.
- Layout: flat folder. ADRs are not nested into category subfolders; topical organization happens via tags.
- Tags: every ADR carries a
tags:array in the MADR frontmatter, drawn from the tag vocabulary below. An ADR may carry several tags. Propose new tags (or renames) in the same PR that needs them; never invent ad-hoc tags inline. - Status lifecycle:
proposed→accepted→ optionallydeprecatedorsuperseded by [ADR-NNNN](NNNN-other.md). Update the YAML frontmatter; never delete an ADR. - Index maintenance: every ADR addition or status change must update the Index below in the same commit.
When to write an ADR
Write one whenever a development decision is non-trivial: tool or library choice, framework pattern, security control, perf budget, a11y target, naming convention, deprecation, breaking change, or any choice that future contributors would benefit from understanding the why of.
Tag vocabulary
The vocabulary below is the source of truth. It is intentionally coarse — propose extensions only when an existing tag genuinely doesn't fit, and avoid overly narrow tags.
| Tag | Scope |
|---|---|
frontend |
UI, Angular, components, design system, client-side state |
backend |
API, BFF, server-side services |
security |
AuthN, AuthZ, sessions, CSP, dependency scanning, secret management |
performance |
Perf budgets, caching, bundle size, Lighthouse |
accessibility |
WCAG, a11y testing, keyboard, ARIA, contrast |
infrastructure |
CI/CD, hosting, deployment, runtime |
observability |
Logs, metrics, traces, correlation IDs, monitoring |
data |
Persistence, schemas, migrations, data flow |
process |
Team conventions, workflows, repo policy |
Status: starter vocabulary, to be refined as ADRs accumulate. Update this table whenever a tag is added, renamed, or retired.
Index
ADRs are listed in numerical order. To slice by topic, filter on the Tags column.
| # | Title | Status | Tags | Date |
|---|---|---|---|---|
| 0001 | Use ADRs to record architectural decisions | accepted | process |
2026-04-29 |
| 0002 | Adopt Nx monorepo with the apps preset |
accepted | infrastructure, frontend, backend |
2026-04-29 |
| 0003 | Workspace and app naming convention | accepted | process |
2026-04-29 |
| 0004 | Frontend stack — Angular (latest LTS), standalone, zoneless, Signals, CSR-only, Vitest | accepted | frontend |
2026-04-29 |
| 0005 | Backend stack — NestJS over Express, Fastify, Hono | accepted | backend |
2026-04-29 |
| 0006 | Persistence — PostgreSQL with Prisma | accepted | data, backend |
2026-04-29 |
| 0007 | Pre-commit hooks and Conventional Commits | accepted | process |
2026-04-29 |
| 0008 | Identity model — multi-tenant Entra ID for workforce, dual-audience design for future External ID | accepted | security, data |
2026-04-29 |
| 0009 | Authentication flow — OIDC Authorization Code + PKCE via MSAL Node, BFF session pattern | accepted | security, backend |
2026-04-29 |
| 0010 | Session management — opaque session IDs in cookies, payload in self-hosted Redis with AES-GCM at rest | accepted | security, backend, infrastructure |
2026-04-29 |
| 0011 | MFA enforcement — Entra ID Conditional Access baseline, BFF claim sanity-check, step-up hooks designed-in | accepted | security |
2026-04-29 |
| 0012 | Observability — Pino structured logs + OpenTelemetry tracing, W3C Trace Context propagation, stdout + collector | accepted | observability, backend, frontend |
2026-04-29 |
| 0013 | Audit trail — separated append-only Postgres schema, decoupled from app logs | accepted | security, observability, data |
2026-04-29 |
| 0014 | Downstream API access — On-Behalf-Of pattern, unified DownstreamApiClient, audience-aware authorization |
accepted | security, backend |
2026-04-29 |
| 0015 | CI/CD pipeline — Gitea Actions, trunk-based + squash-merge, thin YAML over portable scripts | accepted | infrastructure, process |
2026-04-30 |
| 0016 | Accessibility baseline — WCAG 2.2 AA + targeted AAA, Angular CDK + spartan-ng + Tailwind, APF panel testing | accepted | accessibility, frontend, process |
2026-04-30 |
| 0017 | Performance budgets — Core Web Vitals + Lighthouse CI gates, bundle budgets, BFF p95/p99 SLOs | accepted | performance, frontend, backend, process |
2026-04-30 |
| 0018 | Environment configuration — Angular environment.ts, BFF env vars, audit pool split |
accepted | frontend, backend, infrastructure, process |
2026-05-10 |
| 0019 | Internationalisation — @angular/localize, build-time per-locale bundles, /fr + /en path-based routing |
accepted | frontend, accessibility, performance, process |
2026-05-11 |
| 0020 | portal-admin — dedicated SPA for portal administration, sharing the existing BFF |
accepted | frontend, backend, security, infrastructure, process |
2026-05-11 |