fix(anta.tests): First round of cleaning up BGP tests module (#888)

anta/input_models/routing/__init__.py

@@ -0,0 +1,4 @@
+# Copyright (c) 2023-2024 Arista Networks, Inc.
+# Use of this source code is governed by the Apache License 2.0
+# that can be found in the LICENSE file.
+"""Package related to routing tests input models."""

anta/input_models/routing/bgp.py

@@ -0,0 +1,130 @@
+# Copyright (c) 2023-2024 Arista Networks, Inc.
+# Use of this source code is governed by the Apache License 2.0
+# that can be found in the LICENSE file.
+"""Module containing input models for routing BGP tests."""
+
+from __future__ import annotations
+
+from ipaddress import IPv4Address, IPv6Address
+from typing import TYPE_CHECKING, Any
+from warnings import warn
+
+from pydantic import BaseModel, ConfigDict, PositiveInt, model_validator
+
+from anta.custom_types import Afi, Safi
+
+if TYPE_CHECKING:
+    import sys
+
+    if sys.version_info >= (3, 11):
+        from typing import Self
+    else:
+        from typing_extensions import Self
+
+AFI_SAFI_EOS_KEY = {
+    ("ipv4", "unicast"): "ipv4Unicast",
+    ("ipv4", "multicast"): "ipv4Multicast",
+    ("ipv4", "labeled-unicast"): "ipv4MplsLabels",
+    ("ipv4", "sr-te"): "ipv4SrTe",
+    ("ipv6", "unicast"): "ipv6Unicast",
+    ("ipv6", "multicast"): "ipv6Multicast",
+    ("ipv6", "labeled-unicast"): "ipv6MplsLabels",
+    ("ipv6", "sr-te"): "ipv6SrTe",
+    ("vpn-ipv4", None): "ipv4MplsVpn",
+    ("vpn-ipv6", None): "ipv6MplsVpn",
+    ("evpn", None): "l2VpnEvpn",
+    ("rt-membership", None): "rtMembership",
+    ("path-selection", None): "dps",
+    ("link-state", None): "linkState",
+}
+"""Dictionary mapping AFI/SAFI to EOS key representation."""
+
+
+class BgpAddressFamily(BaseModel):
+    """Model for a BGP address family."""
+
+    model_config = ConfigDict(extra="forbid")
+    afi: Afi
+    """BGP Address Family Identifier (AFI)."""
+    safi: Safi | None = None
+    """BGP Subsequent Address Family Identifier (SAFI). Required when `afi` is `ipv4` or `ipv6`."""
+    vrf: str = "default"
+    """Optional VRF when `afi` is `ipv4` or `ipv6`. Defaults to `default`.
+
+    If the input `afi` is NOT `ipv4` or `ipv6` (e.g. `evpn`, `vpn-ipv4`, etc.), the `vrf` must be `default`.
+
+    These AFIs operate at a global level and do not use the VRF concept in the same way as IPv4/IPv6.
+    """
+    num_peers: PositiveInt | None = None
+    """Number of expected established BGP peers with negotiated AFI/SAFI. Required field in the `VerifyBGPPeerCount` test."""
+    peers: list[IPv4Address | IPv6Address] | None = None
+    """List of expected IPv4/IPv6 BGP peers supporting the AFI/SAFI. Required field in the `VerifyBGPSpecificPeers` test."""
+    check_tcp_queues: bool = True
+    """Flag to check if the TCP session queues are empty for a BGP peer. Defaults to `True`.
+
+    Can be disabled in the `VerifyBGPPeersHealth` and `VerifyBGPSpecificPeers` tests.
+    """
+    check_peer_state: bool = False
+    """Flag to check if the peers are established with negotiated AFI/SAFI. Defaults to `False`.
+
+    Can be enabled in the `VerifyBGPPeerCount` tests.
+    """
+
+    @model_validator(mode="after")
+    def validate_inputs(self) -> Self:
+        """Validate the inputs provided to the BgpAddressFamily class.
+
+        If `afi` is either `ipv4` or `ipv6`, `safi` must be provided.
+
+        If `afi` is not `ipv4` or `ipv6`, `safi` must NOT be provided and `vrf` must be `default`.
+        """
+        if self.afi in ["ipv4", "ipv6"]:
+            if self.safi is None:
+                msg = "'safi' must be provided when afi is ipv4 or ipv6"
+                raise ValueError(msg)
+        elif self.safi is not None:
+            msg = "'safi' must not be provided when afi is not ipv4 or ipv6"
+            raise ValueError(msg)
+        elif self.vrf != "default":
+            msg = "'vrf' must be default when afi is not ipv4 or ipv6"
+            raise ValueError(msg)
+        return self
+
+    @property
+    def eos_key(self) -> str:
+        """AFI/SAFI EOS key representation."""
+        # Pydantic handles the validation of the AFI/SAFI combination, so we can ignore error handling here.
+        return AFI_SAFI_EOS_KEY[(self.afi, self.safi)]
+
+    def __str__(self) -> str:
+        """Return a string representation of the BgpAddressFamily model. Used in failure messages.
+
+        Examples
+        --------
+        - AFI:ipv4 SAFI:unicast VRF:default
+        - AFI:evpn
+        """
+        base_string = f"AFI: {self.afi}"
+        if self.safi is not None:
+            base_string += f" SAFI: {self.safi}"
+        if self.afi in ["ipv4", "ipv6"]:
+            base_string += f" VRF: {self.vrf}"
+        return base_string
+
+
+class BgpAfi(BgpAddressFamily):  # pragma: no cover
+    """Alias for the BgpAddressFamily model to maintain backward compatibility.
+
+    When initialized, it will emit a deprecation warning and call the BgpAddressFamily model.
+
+    TODO: Remove this class in ANTA v2.0.0.
+    """
+
+    def __init__(self, **data: Any) -> None:  # noqa: ANN401
+        """Initialize the BgpAfi class, emitting a deprecation warning."""
+        warn(
+            message="BgpAfi model is deprecated and will be removed in ANTA v2.0.0. Use the BgpAddressFamily model instead.",
+            category=DeprecationWarning,
+            stacklevel=2,
+        )
+        super().__init__(**data)