docs/wiki/entities/directus.md

title, type, created, updated, sources, tags

title	type	created	updated	sources	tags
Directus	entity	2026-04-30	2026-05-01	gps-tracking-architecture teltonika-ingestion-architecture	service business-plane api

Directus

The business plane. Owns the relational schema, exposes it through auto-generated REST/GraphQL APIs, enforces role-based permissions, and provides the admin UI for back-office users.

What Directus owns

• Schema management — collections, fields, relations, migrations.
• API generation — REST and GraphQL endpoints, no boilerplate.
• Authentication and authorization — users, roles, permissions, JWT issuance.
• Real-time — WebSocket subscriptions on collections for live UIs.
• Workflow automation — Flows for orchestrating side effects (notifications, integrations).
• Admin UI — complete back-office interface for operators.

What Directus is NOT

Not in the telemetry hot path. Does not accept device connections, run a geofence engine, or hold per-device runtime state. Mixing those responsibilities into the same process would couple deployment lifecycles and contaminate failure domains. See plane-separation.

Schema ownership vs. write access

Directus is the schema owner even though processor writes directly to the database. New tables, columns, and relations are defined through Directus. Reasons:

• Auto-generated admin UI and APIs are derived from the schema Directus knows about. Tables created outside Directus are invisible to it.
• Permissions are configured per-collection in Directus.
• Audit columns (created_at, updated_at, user_created) follow Directus conventions; bypassing them inconsistently leads to subtle UI bugs.

This is a normal Directus deployment pattern — it does not require sole write access, only schema authority.

Extensions

Used for things that genuinely belong in the business layer:

• Hooks that react to data changes (e.g. on event-write, trigger a notification Flow).
• Custom endpoints for permission-gated, audited operations that are not throughput-critical.
• Custom admin UI panels for back-office workflows (data review, manual overrides, bulk ops).
• Flows for declarative orchestration.

Not used for long-running listeners, persistent network sockets, or anything in the telemetry hot path.

Real-time delivery

Directus's WebSocket subscriptions push live data to the react-spa for writes that go through Directus's own services (REST, GraphQL, Admin UI, Flows, custom endpoints). The mechanism is action hooks (action('items.create', ...)) firing from the ItemsService, not Postgres-level change detection.

This means direct database writes from processor are not visible to Directus's subscription system. The platform handles this with two cleanly-separated WebSocket channels:

• directus's WebSocket — broadcasts business-plane events: timing edits, configuration changes, manual entries, anything operators do through the admin UI or via directus's API.
• processor's WebSocket — broadcasts the high-volume telemetry firehose: live position updates fanned out from redis-streams directly to subscribed react-spa clients. Authentication uses Directus-issued JWTs; per-subscription authorization delegates to Directus once at subscribe time.

See live-channel-architecture for the full design, including why this split is preferable to routing telemetry writes through directus's API or running a bridging extension inside directus.

Schema management — snapshot/apply pipeline

Schema changes flow through Directus's native snapshot mechanism, kept under git. Two artifact directories:

• snapshots/schema.yaml — Directus collections, fields, relations. Generated locally with directus schema snapshot. Applied at container startup with directus schema apply --yes. Idempotent — applies only the diff against the running DB.
• db-init/*.sql — schema Directus does not manage: the postgres-timescaledb positions hypertable, the faulty column, indexes that need PostGIS-specific syntax, or any DDL that predates Directus knowing about a collection. Numbered (001_, 002_, …) and applied by a sidecar container or one-shot job ahead of directus schema apply. Tracked via a migrations_applied guard table to skip already-run files.

Local dev edits the schema in the admin UI, then snapshots before commit. CI builds the image with both directories baked in, spins a throwaway Postgres, and dry-runs apply to catch breakage before deploy. Production (Portainer) runs the same apply at container start; multi-env separation is a connection string, not different artifacts.

This treats schema.yaml as the source of truth and the admin UI as its editor. Don't hand-edit schema.yaml; round-trip through the UI to keep the format consistent.

⚠️ Destructive-apply hazard. directus schema apply --yes enforces the snapshot as the single source of truth: anything in the running DB that is not in the snapshot gets deleted during apply. This is correct for fresh-environment provisioning and prod, but a foot-gun during active schema development. The boot pipeline runs apply on every container start (entrypoint step 2/4 — see processor for the analogous staged-apply pattern).

Operator rule: Never restart or rebuild the Directus container while there are uncommitted schema changes. The flow is always: change in admin UI / via MCP → pnpm run schema:snapshot → commit → only then rebuild/restart.

A real incident hit this during Phase 1 task 1.5: 5 newly-created collections were destroyed by a rebuild because the baked-in snapshot was stale. Recovery was straightforward in dev (recreate via MCP, snapshot, commit) but would be data-loss in prod. CI dry-run (Phase 1 task 1.8) catches snapshot drift before it reaches stage. A long-term mitigation — DIRECTUS_SCHEMA_APPLY_MODE env var with auto / dry-run / skip modes — is on the Phase 3 hardening roadmap.

Phase 2 role

Directus owns the commands collection and is the single auth surface for outbound device commands. The SPA inserts command rows; a Directus Flow routes them via Redis to the Ingestion instance holding the device's socket. See phase-2-commands.

Failure mode

Crash → telemetry continues to flow into the database; admin UI and SPA are unavailable; no telemetry is lost. See failure-domains.