navi/backend/README.md

navi-backend

Monorepo of small, single-responsibility HTTP services extracted from the recon codebase as part of the recon ↔ Navi decoupling project. Each service owns a slice of the /api/* surface that navi.echo6.co depends on, runs behind the existing Caddy/Authentik edge, and is fronted by the navi.echo6.co nginx vhost.

See HANDOFF-recon-navi-decoupling-v3.md for the full plan. This repo is extraction #1: navi-traffic.

Layout

navi-backend/
├── shared/                  # cross-service helpers, imported by every service
│   ├── auth.py              # get_user_id(req), require_auth decorator (Authentik header)
│   └── admin_info.py        # build_info_response(), mask_key(), time_dependency()
├── services/
│   └── navi_traffic/        # extraction #1 — TomTom traffic tile proxy (:8421)
│       ├── app.py           # Flask factory (create_app) + gunicorn entry
│       ├── traffic.py       # /api/traffic/flow/<z>/<x>/<y>.png  (ported from recon)
│       ├── admin.py         # /api/admin/navi-traffic/info  (§4.5 admin convention)
│       └── tests/
└── deploy/
    ├── systemd/navi-traffic.service
    └── nginx/navi-traffic.conf.snippet

Service directories use an underscore (navi_traffic) so they're importable Python packages; the service name stays navi-traffic (hyphen) in systemd, nginx, and the admin-info service field.

Setup

Single workspace, single virtualenv:

python -m venv .venv
.venv/bin/pip install -e .

Test

.venv/bin/pytest services/navi_traffic/tests/ -v

Run (local)

TOMTOM_API_KEY=... .venv/bin/gunicorn 'services.navi_traffic.app:create_app()' \
    --bind 127.0.0.1:8421 --workers 2

Run (local) — navi-geo (extraction #6)

.venv/bin/pytest services/navi_geo/tests/ -v

# All paths/URLs are env-overridable (see deploy/env/navi-geo.env.example).
# No secrets — landclass is HTTP-delegated to navi-landclass (:8424).
.venv/bin/gunicorn 'services.navi_geo.app:create_app()' \
    --bind 127.0.0.1:8426 --workers 2

navi-geo serves /api/geocode, /api/reverse?lat=&lon=, and the reverse enrichment bundle /api/reverse/<lat>/<lon> (Central's 9-key contract). All public. The reverse bundle fans out to Photon, the SpatiaLite timezone DB, navi-landclass (HTTP), and the planet-DEM PMTiles — each degrading to null independently, never 5xx.

Run (local) — navi-admin (extraction #7)

.venv/bin/pytest services/navi_admin/tests/ -v

# No secrets — read-only HTTP fan-out over localhost (see
# deploy/env/navi-admin.env.example). Owns no DB.
.venv/bin/gunicorn 'services.navi_admin.app:create_app()' \
    --bind 127.0.0.1:8427 --workers 2

navi-admin is the fleet admin front door: /api/admin/fleet fans out to every navi-* service's localhost /api/admin/<svc>/info + recon's /api/health (merged, never 5xx — failures land in errors[]); /api/admin/recon/info wraps recon's health into the uniform shape; /api/admin/navi-admin/info self-describes. All @require_auth. The per-service admin endpoints stay localhost-only; this is the single edge-exposed admin surface (needs a Caddy @authed_api edit — see deploy/caddy/navi-admin.caddy.notes.md).

Run (local) — navi-offroute (extraction #8)

.venv/bin/pytest services/navi_offroute/tests/ -v

# All paths/URLs env-overridable (deploy/env/navi-offroute.env.example).
# No secrets — PADUS via libpq peer-auth (dbname=padus). DEM via shared/dem.py.
# Needs osmium-tool on the host + scikit-image/rasterio in the venv.
.venv/bin/gunicorn 'services.navi_offroute.app:create_app()' \
    --bind 127.0.0.1:8428 --workers 2 --timeout 130

navi-offroute serves POST /api/offroute (off-network effort-based routing — in-Python least-cost path over a DEM/friction/barriers/trails/MVUM cost grid, stitched to the road network via Valhalla) and GET /api/mvum (Motor Vehicle Use Map road/trail access lookup). Both public. The ^~ /api/offroute nginx block needs a long proxy_read_timeout (130s); routes can take ~2 min.

The admin-info convention (§4.5)

Every service exposes GET /api/admin/<service-name>/info, gated by require_auth, returning a uniform shape: service, version (git SHA), port, config, env (names + masked values), dependencies (upstream health checks), filesystem, runtime (uptime / request count / last error). No aggregator — a future admin panel fans out to each service in parallel.