Unit tests for osism/tasks/conductor/sonic/config_generator.py — BGP/VLAN/Loopback/VRF

[berendt]

Background

Follow-up to #2192 (foundation) and PR #2193 (pytest + Zuul infrastructure). Part of Tier 3 (#2199). Companion issue to the config_generator.py orchestrator and ports issues. Covers BGP, VLAN, Loopback, and VRF helpers in osism/tasks/conductor/sonic/config_generator.py.

Scope

Add tests/unit/tasks/conductor/sonic/test_config_generator_bgp_vlan_vrf.py covering the helpers below in osism/tasks/conductor/sonic/config_generator.py.

Test targets

_add_bgp_configurations(config, connected_interfaces, connected_portchannels, portchannel_info, device, device_as_mapping=None, interface_ips=None, netbox_interfaces=None, transfer_ips=None, netbox=None, vlan_info=None, vrf_info=None) — config_generator.py:914

Patch osism.tasks.conductor.sonic.config_generator.get_connected_device_for_sonic_interface and ...get_connected_interface_ipv4_address.

BGP_NEIGHBOR_AF for connected interfaces (lines 951–1039)

• Untagged VLAN member → excluded (the VLAN-SVI branch handles it instead)
• Direct IPv4 (no transfer role) → excluded from BGP, log message recorded
• No direct IPv4 → ipv4_unicast + ipv6_unicast entries under default|<port>|...
• Transfer-role IPv4 → ipv4_unicast only (v6only=false semantics deferred to BGP_NEIGHBOR test below)
• Switch-to-switch (connected_device.role.slug ∈ DEFAULT_SONIC_ROLES) → l2vpn_evpn entry added
• Non-switch connected device but interface has the BGP_AF_L2VPN_EVPN_TAG tag → l2vpn_evpn entry added
• Non-switch + no tag → l2vpn_evpn skipped
• Non-default VRF (via vrf_info["interface_vrf_mapping"]) → l2vpn_evpn never added
• Port channel member (portchannel_info["member_mapping"]) → skipped from interface BGP loop

BGP_NEIGHBOR_AF for port channels (lines 1040–1079)

• Each connected_portchannel → ipv4_unicast + ipv6_unicast entries
• Switch connection → l2vpn_evpn added
• Non-switch → l2vpn_evpn skipped
• Non-default VRF → l2vpn_evpn never added

BGP_NEIGHBOR for connected interfaces (lines 1081–1179)

• Direct IPv4 only → not added (excluded from BGP detection log)
• Untagged VLAN member → skipped
• No direct IPv4, no peer IP → key is default|<port>, peer_type="external", v6only="true" (default VRF only)
• No direct IPv4, peer IP returned → key is default|<peer_ip>, local_addr set from interface_ips or transfer_ips
• Transfer-role IPv4 → v6only="false"
• Non-default VRF → v6only key not present
• _determine_peer_type returns "internal" (matching AS) → propagated as peer_type

BGP_NEIGHBOR for port channels (lines 1181–1229)

• Default VRF, no peer IP → key default|<pc_name>, peer_type="external", v6only="true"
• Default VRF, peer IP → key uses peer IP; local_addr not set (port channels don't have NetBox interface entries)
• Non-default VRF → v6only not present
• Switch connection → _determine_peer_type evaluated

VLAN-interface BGP (lines 1234–1339)

• VLAN with one untagged member and a peer IPv4 → BGP_NEIGHBOR[default|<peer_ip>] and BGP_NEIGHBOR_AF[default|<peer_ip>|ipv4_unicast] added
• Same peer IP appearing on two untagged members → only one entry (deduped via peer_ips_found)
• VLAN without addresses / no untagged members → skipped
• No untagged member produces a peer IPv4 → warning logged, no entries added
• VLAN interface name (f"Vlan{vid}") used to look up VRF → non-default VRF works
• Member NetBox name not in netbox_interfaces → skipped, debug log

_get_connected_device_for_interface(device, interface_name) — config_generator.py:1342

One delegation test verifying it returns the value from get_connected_device_for_sonic_interface.

_determine_peer_type(local_device, connected_device, device_as_mapping=None) — config_generator.py:1355

Patch calculate_local_asn_from_ipv4.

• Both devices in device_as_mapping with same AS → "internal"
• Both devices with different AS → "external"
• local_device not in mapping but has primary_ip4 → AS computed via patched function
• connected_device not in mapping but has primary_ip4 → AS computed
• Either device has no primary_ip4 and not in mapping → AS None, returns "external"
• calculate_local_asn_from_ipv4 raises → caught, returns "external" (debug log)

_add_vlan_configuration(config, vlan_info, netbox_interfaces, device) — config_generator.py:1700

• VLAN with two members (one tagged, one untagged) → VLAN[Vlan100] populated with members list (sorted by SONiC name); VLAN_MEMBER entries created with the right tagging_mode
• Default vlanid is str(vid); name falls back to f"Vlan{vid}" if NetBox name is empty
• NetBox interface name without a SONiC mapping → warning logged, member skipped
• VLAN interface (SVI) with addresses → VLAN_INTERFACE[Vlan<vid>] = {"admin_status": "up"} and one entry per address (VLAN_INTERFACE[Vlan<vid>|<address>] = {})
• VLAN interface without addresses → no SVI entry

_add_loopback_configuration(config, loopback_info) — config_generator.py:1760

• One Loopback with one IPv4 address → LOOPBACK[name]={admin_status:"up"}, LOOPBACK_INTERFACE[name]={}, LOOPBACK_INTERFACE[name|addr]={}
• Loopback0 with IPv4 → BGP_GLOBALS_AF_NETWORK[default|ipv4_unicast|<addr>]={}
• Loopback0 with IPv6 → BGP_GLOBALS_AF_NETWORK[default|ipv6_unicast|<addr>]={}
• Non-Loopback0 → BGP_GLOBALS_AF_NETWORK not touched
• Invalid IP string → warning logged, skipped

_get_vrf_info(device) — config_generator.py:1793

Patch get_cached_device_interfaces and convert_netbox_interface_to_sonic.

• Interface without VRF → skipped
• Interface VRF name vrf42 (no RD) → Vrf42 definition with table_id=42
• VRF name vrfStorage + numeric RD 2001 → vrfStorage definition with vni=2001
• VRF name vrf2001 + textual RD vrfStorage → SONiC name vrfStorage, vni=2001
• VRF with no name match and a textual RD → uses RD as SONiC name
• VRF with no name match and no RD → warning logged, skipped
• Multiple interfaces in the same VRF → VRF defined once, both interfaces in interface_vrf_mapping
• Per-interface exception → warning logged, processing continues
• Top-level exception (cached interfaces raise) → warning logged, returns {"vrfs": {}, "interface_vrf_mapping": {}}

_add_vrf_configuration(config, vrf_info, netbox_interfaces) — config_generator.py:1937

• VRF with vni → VRF (with fallback="false"), VLAN[Vlan<vni>], VLAN_INTERFACE[Vlan<vni>]={vrf_name:...}, BGP_GLOBALS_AF[<vrf>|ipv4_unicast], BGP_GLOBALS_AF[<vrf>|l2vpn_evpn] with import/export RTs and route-distinguisher, BGP_GLOBALS_ROUTE_ADVERTISE[<vrf>|L2VPN_EVPN|IPV4_UNICAST], BGP_GLOBALS_ROUTE_ADVERTISE[<vrf>|L2VPN_EVPN|IPV6_UNICAST], ROUTE_REDISTRIBUTE[<vrf>|connected|bgp|ipv4]
• VRF with table_id only → VRF[<vrf>]={vrf_table_id: <id>}
• VRF with neither → VRF[<vrf>]={}
• BGP_GLOBALS["default"] exists → deep-copied to BGP_GLOBALS[<vrf>]
• Multiple VRFs with VNI → VXLAN_TUNNEL/VXLAN_EVPN_NVO/VXLAN_TUNNEL_MAP entries created (one map per VRF)
• No VRF with VNI → VXLAN sections not created
• Interface in vrf_info["interface_vrf_mapping"] and in config["INTERFACE"] → vrf_name set on the interface
• Interface in vrf_info["interface_vrf_mapping"] and in config["PORTCHANNEL_INTERFACE"] → vrf_name set on the port channel
• Interface in mapping but in neither section → debug log, no error

Mocking hints

• Build vrf_info, vlan_info, netbox_interfaces, interface_ips, transfer_ips inline as plain dicts.
• Initialize config with all keys the helpers mutate (BGP_NEIGHBOR, BGP_NEIGHBOR_AF, VLAN, VLAN_MEMBER, VLAN_INTERFACE, LOOPBACK, LOOPBACK_INTERFACE, BGP_GLOBALS_AF_NETWORK, VRF, VXLAN_TUNNEL, VXLAN_EVPN_NVO, VXLAN_TUNNEL_MAP, BGP_GLOBALS_AF, BGP_GLOBALS_ROUTE_ADVERTISE, INTERFACE, PORTCHANNEL_INTERFACE).
• device.config_context.get(...) is consulted in _add_log_server_configuration and _add_snmp_configuration (covered in the orchestrator issue), not here.
• Construct interfaces with SimpleNamespace and a nested vrf=SimpleNamespace(name="...", rd="...").
• BGP_AF_L2VPN_EVPN_TAG comes from osism.tasks.conductor.sonic.constants — mock interfaces with tags=[SimpleNamespace(slug=BGP_AF_L2VPN_EVPN_TAG)].

Definition of Done

• tests/unit/tasks/conductor/sonic/test_config_generator_bgp_vlan_vrf.py created
• All listed cases covered
• pytest --cov=osism.tasks.conductor.sonic.config_generator for the targeted functions ≥ 85 %
• pipenv run pytest tests/unit/tasks/conductor/sonic/test_config_generator_bgp_vlan_vrf.py passes locally
• flake8, mypy, python-black remain green
• Zuul job python-osism-unit-tests passes

Dependencies

• Part of Meta: Unit test coverage for osism/ #2199 (meta). Blocked by Introduce foundation for unit tests (pytest + Zuul CI integration) #2192 / PR Introduce foundation for unit tests (pytest + Zuul CI) #2193.