Enhancement: Input subclasses refactoring

[gmuloc]

Tests Input subclasses should be moved outside of test classes, in other modules to allow reusability across tests and easier imports by external framework leveraging ANTA (AVD).

Solution:

Models are being moved to anta.input_models.<module>. Each test will keep a class variable as a reference of these models to avoid breaking changes. The references will be removed in ANTA v2.0.

Example:

from anta.input_models.connectivity import Host

class Input(AntaTest.Input):
    """Input model for the VerifyReachability test."""

    hosts: list[Host]
    """List of host to ping."""
    Host: ClassVar[type[Host]] = Host

• As part of this refactoring, model_config = ConfigDict(extra="forbid") should be added to these models to fix Extra attributes should be forbidden in nested Input models #809.
• A __str__ should also be added to the models and be leveraged to improve failure messages, to fix Have nicer result failure messages #587.
• Need to add documentation for input models. Ref fix(anta.tests): Fix VerifyReachability failure messages #912

Checklist (in priority):

High priority (AVD tests or high reusability):

• VerifyReachability.Input.Host fix(anta.tests): Fix VerifyReachability failure messages #912
• VerifyInterfacesStatus.Input.InterfaceState refactor(anta): Refactor VerifyInterfacesStatus test for nicer failure message #899
• VerifyNTPAssociations.Input.NTPServer fix(anta.tests): Fix VerifyNTPAssociations to support IP-DNS peers #902
• VerifyLLDPNeighbors.Input.Neighbor refactor(anta): Refactor VerifyLLDPNeighbors test for nicer failure message #915
• VerifySpecificIPSecConn.Input.IPSecPeers & IPSecConn - @vitthalmagadum
• VerifyStunClient..Input.ClientAddress - @vitthalmagadum
• VerifyAVTSpecificPath.Input.AVTPaths - @vitthalmagadum
• VerifyDNSServers.Input.DnsServer refactor(anta): Refactor VerifyDNSServers test for nicer failure message  #920

The following 3 BGP tests should use the same model to replace <VerifyBGP...>.Input.BgpAfi:

• VerifyBGPPeerCount, VerifyBGPPeersHealth, VerifyBGPSpecificPeers fix(anta.tests): First round of cleaning up BGP tests module #888

These BGP tests should use the same BgpPeer model:

• VerifyBGPPeerMPCaps fix(anta.tests): Second round of cleaning up BGP tests module #914
• VerifyBGPPeerASNCap fix(anta.tests): Second round of cleaning up BGP tests module #914
• VerifyBGPPeerRouteRefreshCap fix(anta.tests): Second round of cleaning up BGP tests module #914
• VerifyBGPPeerMD5Auth fix(anta.tests): Second round of cleaning up BGP tests module #914
• VerifyBGPAdvCommunities fix(anta.tests): Second round of cleaning up BGP tests module #914
• VerifyBGPTimers fix(anta.tests): Second round of cleaning up BGP tests module #914
• VerifyBGPPeerDropStats fix(anta.tests): Second round of cleaning up BGP tests module #914
• VerifyBGPPeerUpdateErrors fix(anta.tests): Second round of cleaning up BGP tests module #914
• VerifyBgpRouteMaps fix(anta.tests): Second round of cleaning up BGP tests module #914
• VerifyBGPPeerRouteLimit fix(anta.tests): Second round of cleaning up BGP tests module #914

The BFD tests should use the same BFDPeer model:

• VerifyBFDSpecificPeers, VerifyBFDPeersIntervals, VerifyBFDPeersRegProtocols - fix(anta.tests): Cleaning up BFD tests module #926

Low priority (low reusability):

• VerifyLACPInterfacesStatus.Input.LACPInterface
• VerifyErrdisableRecovery.Input.ErrDisableReason
• VerifyAPISSLCertificate.Input.APISSLCertificate
• VerifyIPv4ACL.Input.IPv4ACL & IPv4ACLEntry
• VerifySpecificPath.Input.RouterPath
• VerifyHardwareFlowTrackerStatus.Input.FlowTracker & RecordExport & Exporter
• VerifyISISNeighborCount.Input.InterfaceCount
• VerifyISISInterfaceMode.Input.InterfaceState
• VerifyISISSegmentRoutingAdjacencySegments.Input.IsisInstance & Segment
• VerifyISISSegmentRoutingDataplane.Input.IsisInstance
• VerifyISISSegmentRoutingTunnels.Input.Entry & Vias