feat: add YANG path constants module

Python module with validated gNMI YANG paths for: - Interfaces, Loopbacks, VLANs (OpenConfig) - BGP with neighbor and AFI-SAFI helpers (OpenConfig) - VXLAN VNI mappings (Arista experimental) - MLAG and EVPN config (Arista experimental) - Port-Channel/LAG paths - Subscription helpers for fabric monitoring Part of #3
2025-12-26 13:42:31 +00:00
parent 4c7634da59
commit f335d1fc33
1 changed files with 345 additions and 0 deletions
--- a/src/yang/paths.py
+++ b/src/yang/paths.py
@@ -0,0 +1,345 @@
+"""
+YANG Path Constants for Arista EOS 4.35.0F
+
+This module provides validated gNMI YANG paths for managing
+Arista EVPN-VXLAN fabrics via gNMI.
+
+Usage:
+    from yang.paths import Interfaces, BGP, VXLAN
+
+    # Get interface state path
+    path = Interfaces.state("Ethernet1")
+
+    # Get all BGP neighbors
+    path = BGP.NEIGHBORS
+"""
+
+from dataclasses import dataclass
+from typing import Optional
+
+
+# =============================================================================
+# Interfaces (OpenConfig)
+# =============================================================================
+
+class Interfaces:
+    """OpenConfig interface paths."""
+
+    # Base paths
+    ROOT = "/interfaces/interface"
+
+    @staticmethod
+    def interface(name: str) -> str:
+        """Get path for specific interface."""
+        return f"/interfaces/interface[name={name}]"
+
+    @staticmethod
+    def config(name: str) -> str:
+        """Get interface config path."""
+        return f"/interfaces/interface[name={name}]/config"
+
+    @staticmethod
+    def state(name: str) -> str:
+        """Get interface state path."""
+        return f"/interfaces/interface[name={name}]/state"
+
+    @staticmethod
+    def oper_status(name: str) -> str:
+        """Get interface operational status path."""
+        return f"/interfaces/interface[name={name}]/state/oper-status"
+
+    @staticmethod
+    def admin_status(name: str) -> str:
+        """Get interface admin status path."""
+        return f"/interfaces/interface[name={name}]/state/admin-status"
+
+    @staticmethod
+    def counters(name: str) -> str:
+        """Get interface counters path."""
+        return f"/interfaces/interface[name={name}]/state/counters"
+
+
+# =============================================================================
+# Loopbacks (OpenConfig)
+# =============================================================================
+
+class Loopbacks:
+    """Loopback interface paths."""
+
+    @staticmethod
+    def interface(index: int) -> str:
+        """Get loopback interface path."""
+        return f"/interfaces/interface[name=Loopback{index}]"
+
+    @staticmethod
+    def config(index: int) -> str:
+        """Get loopback config path."""
+        return f"/interfaces/interface[name=Loopback{index}]/config"
+
+    # Common loopbacks
+    LOOPBACK0 = "/interfaces/interface[name=Loopback0]"
+    LOOPBACK1 = "/interfaces/interface[name=Loopback1]"  # VTEP source
+
+
+# =============================================================================
+# VLANs (OpenConfig)
+# =============================================================================
+
+class VLANs:
+    """OpenConfig VLAN paths."""
+
+    # Base path
+    ROOT = "/network-instances/network-instance[name=default]/vlans/vlan"
+
+    @staticmethod
+    def vlan(vlan_id: int) -> str:
+        """Get specific VLAN path."""
+        return f"/network-instances/network-instance[name=default]/vlans/vlan[vlan-id={vlan_id}]"
+
+    @staticmethod
+    def config(vlan_id: int) -> str:
+        """Get VLAN config path."""
+        return f"/network-instances/network-instance[name=default]/vlans/vlan[vlan-id={vlan_id}]/config"
+
+    @staticmethod
+    def svi(vlan_id: int) -> str:
+        """Get SVI interface path."""
+        return f"/interfaces/interface[name=Vlan{vlan_id}]"
+
+
+# =============================================================================
+# BGP (OpenConfig)
+# =============================================================================
+
+class BGP:
+    """OpenConfig BGP paths."""
+
+    # Base path for BGP
+    _BASE = "/network-instances/network-instance[name=default]/protocols/protocol[identifier=BGP][name=BGP]/bgp"
+
+    # Global paths
+    GLOBAL = f"{_BASE}/global"
+    GLOBAL_CONFIG = f"{_BASE}/global/config"
+    GLOBAL_STATE = f"{_BASE}/global/state"
+
+    # Neighbors
+    NEIGHBORS = f"{_BASE}/neighbors/neighbor"
+
+    @staticmethod
+    def neighbor(address: str) -> str:
+        """Get specific neighbor path."""
+        return f"{BGP._BASE}/neighbors/neighbor[neighbor-address={address}]"
+
+    @staticmethod
+    def neighbor_config(address: str) -> str:
+        """Get neighbor config path."""
+        return f"{BGP._BASE}/neighbors/neighbor[neighbor-address={address}]/config"
+
+    @staticmethod
+    def neighbor_state(address: str) -> str:
+        """Get neighbor state path."""
+        return f"{BGP._BASE}/neighbors/neighbor[neighbor-address={address}]/state"
+
+    @staticmethod
+    def neighbor_session_state(address: str) -> str:
+        """Get neighbor session state path."""
+        return f"{BGP._BASE}/neighbors/neighbor[neighbor-address={address}]/state/session-state"
+
+    @staticmethod
+    def neighbor_afi_safi(address: str, afi_safi: str) -> str:
+        """
+        Get neighbor AFI-SAFI path.
+
+        Args:
+            address: Neighbor IP address
+            afi_safi: AFI-SAFI name (e.g., 'IPV4_UNICAST', 'L2VPN_EVPN')
+        """
+        return f"{BGP._BASE}/neighbors/neighbor[neighbor-address={address}]/afi-safis/afi-safi[afi-safi-name={afi_safi}]"
+
+
+# AFI-SAFI constants
+class AfiSafi:
+    """BGP AFI-SAFI identifiers."""
+
+    IPV4_UNICAST = "IPV4_UNICAST"
+    IPV6_UNICAST = "IPV6_UNICAST"
+    L2VPN_EVPN = "L2VPN_EVPN"
+
+
+# =============================================================================
+# VXLAN (Arista Experimental)
+# =============================================================================
+
+class VXLAN:
+    """
+    Arista VXLAN paths.
+
+    Model: arista-exp-eos-vxlan (augments openconfig-interfaces)
+    """
+
+    # Base paths
+    INTERFACE = "/interfaces/interface[name=Vxlan1]"
+    ROOT = "/interfaces/interface[name=Vxlan1]/arista-vxlan"
+    CONFIG = "/interfaces/interface[name=Vxlan1]/arista-vxlan/config"
+    STATE = "/interfaces/interface[name=Vxlan1]/arista-vxlan/state"
+
+    # Specific config leaves
+    SOURCE_INTERFACE = "/interfaces/interface[name=Vxlan1]/arista-vxlan/config/src-ip-intf"
+    UDP_PORT = "/interfaces/interface[name=Vxlan1]/arista-vxlan/config/udp-port"
+
+    # VNI mappings
+    VLAN_TO_VNIS = "/interfaces/interface[name=Vxlan1]/arista-vxlan/vlan-to-vnis"
+    VRF_TO_VNIS = "/interfaces/interface[name=Vxlan1]/arista-vxlan/vrf-to-vnis"
+
+    @staticmethod
+    def vlan_to_vni(vlan_id: int) -> str:
+        """Get specific VLAN-to-VNI mapping path."""
+        return f"/interfaces/interface[name=Vxlan1]/arista-vxlan/vlan-to-vnis/vlan-to-vni[vlan={vlan_id}]"
+
+    @staticmethod
+    def vrf_to_vni(vrf_name: str) -> str:
+        """Get specific VRF-to-VNI mapping path."""
+        return f"/interfaces/interface[name=Vxlan1]/arista-vxlan/vrf-to-vnis/vrf-to-vni[vrf={vrf_name}]"
+
+
+# =============================================================================
+# MLAG (Arista Experimental)
+# =============================================================================
+
+class MLAG:
+    """
+    Arista MLAG paths.
+
+    Model: arista-exp-eos-mlag
+
+    WARNING: Only config is exposed via gNMI.
+    State (peer status, role) requires eAPI.
+    """
+
+    ROOT = "/arista/eos/mlag"
+    CONFIG = "/arista/eos/mlag/config"
+
+    # Config fields (for reference)
+    # - domain-id
+    # - local-intf
+    # - peer-address
+    # - peer-link-intf
+    # - dual-primary-action
+    # - dual-primary-detection-delay
+    # - heartbeat-peer-address
+
+
+# =============================================================================
+# EVPN (Arista Experimental)
+# =============================================================================
+
+class EVPN:
+    """
+    Arista EVPN paths.
+
+    Model: arista-exp-eos-evpn
+
+    WARNING: Only config is exposed via gNMI.
+    Learned routes/MACs require eAPI.
+    """
+
+    ROOT = "/arista/eos/evpn"
+    INSTANCES = "/arista/eos/evpn/evpn-instances"
+
+    @staticmethod
+    def instance(name: str) -> str:
+        """Get specific EVPN instance path."""
+        return f"/arista/eos/evpn/evpn-instances/evpn-instance[name={name}]"
+
+    @staticmethod
+    def instance_config(name: str) -> str:
+        """Get EVPN instance config path."""
+        return f"/arista/eos/evpn/evpn-instances/evpn-instance[name={name}]/config"
+
+    @staticmethod
+    def route_target(name: str) -> str:
+        """Get EVPN instance route-target path."""
+        return f"/arista/eos/evpn/evpn-instances/evpn-instance[name={name}]/route-target/config"
+
+
+# =============================================================================
+# Port-Channel / LAG (OpenConfig)
+# =============================================================================
+
+class PortChannel:
+    """OpenConfig LAG/Port-Channel paths."""
+
+    @staticmethod
+    def interface(channel_id: int) -> str:
+        """Get port-channel interface path."""
+        return f"/interfaces/interface[name=Port-Channel{channel_id}]"
+
+    @staticmethod
+    def config(channel_id: int) -> str:
+        """Get port-channel config path."""
+        return f"/interfaces/interface[name=Port-Channel{channel_id}]/config"
+
+    @staticmethod
+    def aggregation(channel_id: int) -> str:
+        """Get LAG aggregation config path."""
+        return f"/interfaces/interface[name=Port-Channel{channel_id}]/aggregation/config"
+
+    @staticmethod
+    def aggregation_state(channel_id: int) -> str:
+        """Get LAG aggregation state path."""
+        return f"/interfaces/interface[name=Port-Channel{channel_id}]/aggregation/state"
+
+
+# =============================================================================
+# System (OpenConfig)
+# =============================================================================
+
+class System:
+    """OpenConfig system paths."""
+
+    ROOT = "/system"
+    CONFIG = "/system/config"
+    STATE = "/system/state"
+    HOSTNAME = "/system/config/hostname"
+
+
+# =============================================================================
+# Subscription Helpers
+# =============================================================================
+
+@dataclass
+class SubscriptionPath:
+    """Helper for building subscription paths."""
+
+    path: str
+    mode: str = "on-change"  # on-change, sample, target-defined
+
+    def __str__(self) -> str:
+        return self.path
+
+
+# Common subscription paths for fabric monitoring
+class FabricSubscriptions:
+    """Pre-defined subscription paths for fabric monitoring."""
+
+    # Interface state changes
+    INTERFACE_STATE = SubscriptionPath("/interfaces/interface/state")
+
+    # BGP session state changes
+    BGP_SESSIONS = SubscriptionPath(
+        "/network-instances/network-instance[name=default]/protocols/protocol[identifier=BGP][name=BGP]/bgp/neighbors/neighbor/state/session-state"
+    )
+
+    # VXLAN VNI changes
+    VXLAN_VNIS = SubscriptionPath(
+        "/interfaces/interface[name=Vxlan1]/arista-vxlan/vlan-to-vnis"
+    )
+
+    @classmethod
+    def all(cls) -> list[SubscriptionPath]:
+        """Get all fabric subscription paths."""
+        return [
+            cls.INTERFACE_STATE,
+            cls.BGP_SESSIONS,
+            cls.VXLAN_VNIS,
+        ]