## Summary
Pure documentation PR. Two ADRs that answer the two strategic questions raised after the footer chantier:
- **[ADR-0019](docs/decisions/0019-internationalisation-angular-localize.md)** — how the portal handles multiple languages.
- **[ADR-0020](docs/decisions/0020-portal-admin-app.md)** — where portal administration lives.
Implementation will land across follow-up feature PRs, each consumable on its own.
## ADR-0019 — Internationalisation
**Decision:** `@angular/localize` in **build-time** mode, two locales (`fr` default served at `/`, `en` source). Path-based URLs always prefixed (`/fr/...`, `/en/...`); `/` smart-redirects via cookie → `Accept-Language` → `fr`. The locale switcher in the footer writes a `__Host-portal_locale` cookie and hard-refreshes to the matching bundle.
**Considered and rejected:**
- `@angular/localize` runtime mode (single bundle, higher LCP / payload cost).
- `@ngx-translate` / `transloco` (community libraries; tech-bar prefers Angular first-party for foundational primitives).
- Query-param URL strategy (fragile, weaker SEO, `<html lang>` becomes harder).
- Subdomain URL strategy (breaks `__Host-` cookie scoping from ADR-0010).
**Scope boundary:** UI strings owned by developers (templates + `$localize` in code). Editorial content (CMS-managed pages, news, etc.) is BFF-served already localised — that's the admin-app pipeline (ADR-0020), not `@angular/localize`.
**First sweep consequence:** the duplicate `/accessibility` + `/accessibilite` routes collapse to one Angular route with locale-translated paths.
## ADR-0020 — `portal-admin`
**Decision:** new Angular SPA `portal-admin` alongside `portal-shell`, sharing the existing `portal-bff` via `/api/admin/*` routes guarded by an Entra `admin` role plus `@RequireMfa({ freshness: 600 })` at the entry route. Distinct origin + cookie + session (`__Host-portal_admin_session`).
**v1 modules** (all four selected):
1. Editorial pages CMS (multilingual content, fed back to `portal-shell` via the BFF).
2. Sidebar menu management (activates the `requiredPermissions` field already on `MenuItem`).
3. User list (read-only).
4. Audit log viewer (consumes the `audit.events` table per ADR-0013, via the `audit_reader` role).
**Out of v1:** B2B invitations (stay in Entra Admin Center), feature flags (no substrate yet), CMS workflow / approval flows, theme customisation, live preview.
**Considered and rejected:**
- `/admin/*` lazy-loaded inside `portal-shell` (admin code in the same origin → weaker defense in depth, admin URL not IP-restrictable independently).
- Two SPAs **and** two BFFs (doubles infra at our scale — bricolage).
- Off-the-shelf admin tooling (Retool, etc. — escapes our security baseline).
**Performance budget for admin:** ≤ 500 KB gzip initial (vs 300 KB for `portal-shell`, per ADR-0017). Lighthouse Performance ≥ 85 on critical admin routes (vs ≥ 90 on `portal-shell`). Same a11y baseline (ADR-0016), same dark-mode support.
**Shared-libs graduation:** `Icon`, `LayoutStateService`, brand tokens, dark-mode SCSS helpers move from `portal-shell` to `libs/shared/{ui,state}` when both apps need them. Mechanical refactor; tracked as the first implementation PR.
## Implementation roadmap (out of scope of this PR)
ADR-0019:
1. Install `@angular/localize`, wire build target.
2. Mark every existing UI string in `portal-shell` with `i18n` + `@@id`; produce `messages.fr.xlf`.
3. Locale switcher in footer + `/api/preferences/locale` BFF route + smart redirect at `/`.
4. Collapse the duplicate accessibility routes into a localised single route, with 301s.
5. CI gate: `nx build portal-shell --localize` is added to `ci:check` and fails on missing translation.
ADR-0020:
1. `nx g @nx/angular:app portal-admin` skeleton.
2. Shared-libs extraction (`libs/shared/ui`, `libs/shared/state`).
3. BFF `AdminModule` + `AdminRoleGuard` + smoke `GET /api/admin/me`.
4. Admin shell (header / sidebar / footer with an "Admin" badge).
5. One PR per v1 module — suggested order: CMS pages → menu management → audit viewer → user list.
## Test plan
- [x] Both ADRs follow MADR 4.0.0 (frontmatter, sections, tags from the canonical vocabulary).
- [x] `docs/decisions/README.md` index updated in the same commit.
- [x] `CLAUDE.md` architecture summary picks up entries for both decisions and bumps the ADR coverage line to 0020.
- [ ] Read-through review — invite the project lead to push back on any decision before locking implementation.
---------
Co-authored-by: Julien Gautier <julien.gautier@apf.asso.fr>
Reviewed-on: #89
8.9 KiB
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 |