feat(api/topology): pending-only child CRUD for LANs, deckies, edges

decnet/web/router/topology/api_lan_crud.py

@@ -0,0 +1,149 @@
+"""LAN CRUD endpoints — pending-only child mutations.
+
+    POST   /topologies/{id}/lans
+    PATCH  /topologies/{id}/lans/{lan_id}
+    DELETE /topologies/{id}/lans/{lan_id}
+"""
+from __future__ import annotations
+
+from fastapi import APIRouter, Depends, HTTPException, Response, status
+
+from decnet.telemetry import traced as _traced
+from decnet.topology.allocator import reserved_subnets
+from decnet.topology.status import (
+    TopologyNotEditable,
+    VersionConflict,
+)
+from decnet.web.db.models import LANCreateRequest, LANRow, LANUpdateRequest
+from decnet.web.dependencies import repo, require_admin
+
+from ._guards import assert_pending_or_409, map_repo_exception
+
+router = APIRouter()
+
+
+@router.post(
+    "/{topology_id}/lans",
+    tags=["MazeNET Topologies"],
+    response_model=LANRow,
+    status_code=status.HTTP_201_CREATED,
+    responses={
+        400: {"description": "Malformed body or invalid LAN fields"},
+        401: {"description": "Missing or invalid credentials"},
+        403: {"description": "Insufficient permissions"},
+        404: {"description": "Topology not found"},
+        409: {"description": "Topology not editable or version conflict"},
+    },
+)
+@_traced("api.topology.lan.create")
+async def api_create_lan(
+    topology_id: str,
+    body: LANCreateRequest,
+    _admin: dict = Depends(require_admin),
+) -> LANRow:
+    await assert_pending_or_409(topology_id)
+
+    subnet = body.subnet
+    if subnet is None:
+        # Mint a free /24.  The allocator scans the claimed set and hands
+        # back the next free subnet base — same logic as the catalog
+        # /next-subnet endpoint, but inlined so create is atomic.
+        from decnet.topology.allocator import SubnetAllocator
+
+        allocator = SubnetAllocator(
+            "10.0.0.0/16", reserved=await reserved_subnets(repo)
+        )
+        subnet = allocator.next_free()
+
+    payload = {
+        "topology_id": topology_id,
+        "name": body.name,
+        "subnet": subnet,
+        "is_dmz": body.is_dmz,
+        "x": body.x,
+        "y": body.y,
+    }
+    try:
+        lan_id = await repo.add_lan(
+            payload, expected_version=body.expected_version
+        )
+    except (TopologyNotEditable, VersionConflict, ValueError) as exc:
+        raise map_repo_exception(exc) from exc
+
+    rows = await repo.list_lans_for_topology(topology_id)
+    row = next((r for r in rows if r["id"] == lan_id), None)
+    if row is None:  # pragma: no cover — would mean insert vanished
+        raise HTTPException(status_code=500, detail="LAN insert vanished")
+    return LANRow(**row)
+
+
+@router.patch(
+    "/{topology_id}/lans/{lan_id}",
+    tags=["MazeNET Topologies"],
+    response_model=LANRow,
+    responses={
+        400: {"description": "Malformed body or invalid LAN fields"},
+        401: {"description": "Missing or invalid credentials"},
+        403: {"description": "Insufficient permissions"},
+        404: {"description": "Topology or LAN not found"},
+        409: {"description": "Topology not editable or version conflict"},
+    },
+)
+@_traced("api.topology.lan.update")
+async def api_update_lan(
+    topology_id: str,
+    lan_id: str,
+    body: LANUpdateRequest,
+    _admin: dict = Depends(require_admin),
+) -> LANRow:
+    await assert_pending_or_409(topology_id)
+
+    fields = body.model_dump(exclude_unset=True, exclude={"expected_version"})
+    try:
+        await repo.update_lan(
+            lan_id,
+            fields,
+            expected_version=body.expected_version,
+            enforce_pending=True,
+        )
+    except (TopologyNotEditable, VersionConflict) as exc:
+        raise map_repo_exception(exc) from exc
+    except ValueError as exc:
+        raise HTTPException(status_code=404, detail=str(exc)) from exc
+
+    rows = await repo.list_lans_for_topology(topology_id)
+    row = next((r for r in rows if r["id"] == lan_id), None)
+    if row is None:
+        raise HTTPException(status_code=404, detail="LAN not found")
+    return LANRow(**row)
+
+
+@router.delete(
+    "/{topology_id}/lans/{lan_id}",
+    tags=["MazeNET Topologies"],
+    status_code=status.HTTP_204_NO_CONTENT,
+    responses={
+        400: {"description": "Cannot delete: LAN has orphan-risking deckies"},
+        401: {"description": "Missing or invalid credentials"},
+        403: {"description": "Insufficient permissions"},
+        404: {"description": "Topology or LAN not found"},
+        409: {"description": "Topology not editable or version conflict"},
+    },
+)
+@_traced("api.topology.lan.delete")
+async def api_delete_lan(
+    topology_id: str,
+    lan_id: str,
+    _admin: dict = Depends(require_admin),
+) -> Response:
+    await assert_pending_or_409(topology_id)
+
+    rows = await repo.list_lans_for_topology(topology_id)
+    if not any(r["id"] == lan_id for r in rows):
+        raise HTTPException(status_code=404, detail="LAN not found")
+
+    try:
+        await repo.delete_lan(lan_id)
+    except (TopologyNotEditable, VersionConflict, ValueError) as exc:
+        raise map_repo_exception(exc) from exc
+    return Response(status_code=status.HTTP_204_NO_CONTENT)