weirsoe-party-protocol/docs/ISSUE-175-I18N-SHARED-CONTRACT-ARTIFACT.md

ISSUE-175 Artifact — shared i18n contract + MVP host/player flow

Delivered

• Shared i18n contract is centralized in shared/i18n/lobby.json (da/en, default en, robust fallback).
• Frontend host/player MVP copy is read via shared keys (no hardcoded Danish strings in Angular MVP flow components).
• Backend error messages resolve from shared keyspace with locale-aware API payload (error_code, error, locale).
• Audio-routing policy is explicit and shared: frontend.capabilities.client_has_no_audio_output=true.
• Architecture + key naming documented in docs/I18N_ARCHITECTURE.md.

Smoke / e2e evidence

Backend locale + fallback

Command:

. .venv/bin/activate && python manage.py test \
  lobby.tests.LobbyFlowTests.test_join_error_localizes_to_danish_with_accept_language_header \
  lobby.tests.LobbyFlowTests.test_join_error_falls_back_to_english_for_unsupported_locale \
  lobby.tests.I18nResolverTests

Result:

• PASS (7 tests)
• Confirms da localization and fallback to en for unsupported locale.

Frontend host/player + language switch + audio policy

Command:

cd frontend/angular
npm test -- --run \
  src/app/lobby-i18n.spec.ts \
  src/app/i18n-mvp-flow-smoke.spec.ts \
  src/app/features/host/host-shell.component.spec.ts \
  src/app/features/player/player-shell.component.spec.ts

Result:

• PASS (22 tests)
• Includes smoke for host/player copy in both en and da and verifies primary-only audio policy flag (clientHasNoAudioOutput=true).