After the DB writes that record the multi-home edge, calls the docker
SDK directly to add an interface to the base container's netns:
client.networks.get(<topology bridge>).connect(<base>, ipv4_address=ip)
Non-destructive — the base keeps running, no recreate. Service
containers automatically see the new interface because they share
the base's netns via network_mode: service:<base>.
Idempotency: docker APIError with 'already' / 'endpoint exists' is
logged at info and treated as success. Other errors log + leave the
DB row in place; an operator retry will hit the same path.
Captures the decky's name and services list before delete_topology_decky
runs (the helper needs both as compose targets even though the DB row
is gone), then calls _materialise_decky_remove which stops + rm -f's
the base + per-service containers via 'docker compose stop / rm -f'.
Re-renders the per-topology compose AFTER the stop/rm so a future
'compose up -d' on the file doesn't try to bring the decky back.
Adds _materialise_decky_{spawn,remove,connect,disconnect,services_diff,recreate_base}
helpers alongside the existing _materialise_lan_change. Each follows
the same skip rules: bail when topology is not active/degraded, when
agent-pinned, or when docker calls fail (logged, not re-raised — DB
remains source of truth).
apply_add_decky now calls _materialise_decky_spawn after the DB writes.
The helper:
* re-renders the per-topology compose so it lists the new decky;
* runs 'compose up -d --no-deps --build <decky_base> <decky>-<svc>...'
in a worker thread (matches engine/services_live's pattern).
Service container targets are filtered through get_service() so
fleet_singleton services are skipped — they don't have per-decky
compose entries. Gateway (forwards_l3=True) deckies need no
special-case here; the compose generator already emits the host
'ports:' block for them.
Subsequent commits wire the other apply_* ops to the matching
helpers. Tests for the full set ship in the workstream's last
commit.
subnet and is_dmz are pinned at deploy time — live deckies bind to
the bridge with IPs allocated from the old subnet, and is_dmz flips
the docker network's internal flag which can't be changed while
containers are attached. Today the op happily wrote the new value
into the DB and left docker on the old one, drifting the two surfaces.
apply_update_lan now raises MutationError when topology status is
active or degraded and the patch touches subnet or is_dmz. Coord
(x/y) and rename updates still pass through; renames don't currently
have a live caller and the bridge's docker name keys off the lan name
in the renderer, so the next deploy will reconcile.
This matches the posture taken by _materialise_lan_change for live
LAN add/remove (commit 472c84b).
apply_add_lan and apply_remove_lan were DB-only — they wrote/deleted
the topology_lans row but never created or destroyed the docker bridge
network. Adding a LAN to a deployed topology silently did nothing on
the substrate side; any decky later attached to it had nowhere to bind.
Both ops now call a shared _materialise_lan_change helper after the DB
write. When the topology is active/degraded and not pinned to a swarm
agent, the helper:
* creates / removes the docker bridge network (internal=True for
non-DMZ LANs, mirroring engine/deployer.deploy_topology),
* re-renders the per-topology compose file so future redeploys reflect
the change.
Failures are logged, not re-raised — the DB row stays as source of
truth so an operator can retry without leaking inconsistent state.
Agent-pinned topologies are skipped; the next agent push reconciles.
apply_add_decky / apply_attach_decky have the same gap and are not
fixed here — multi-homing a running container needs careful
recreate-vs-network-connect handling and is its own commit. Without
those, dropping a decky into a freshly-added LAN still won't spawn a
container; only the LAN itself is now live.
