[dualtor]: Add utilities for dual ToR mocking (#2945)

* [dualtor]: Add utilities for dual ToR mocking

* Apply config DB tables to mock dual ToR setup
* Apply kernel configurations (neighbor entries and route)
* Apply orchagent config to mock dual ToR setup

Signed-off-by: Lawrence Lee <lawlee@microsoft.com>

Author: theasianpianist

tests/common/dualtor/dual_tor_mock.py

@@ -0,0 +1,327 @@
+import json
+import logging
+import os
+import pytest
+
+from ipaddress import ip_interface, IPv4Interface, IPv6Interface, \
+                      ip_address, IPv4Address
+
+__all__ = ['apply_active_state_to_orchagent', 'apply_dual_tor_neigh_entries', 'apply_dual_tor_peer_switch_route', 'apply_mock_dual_tor_kernel_configs',
+           'apply_mock_dual_tor_tables', 'apply_mux_cable_table_to_dut', 'apply_peer_switch_table_to_dut', 'apply_standby_state_to_orchagent', 'apply_tunnel_table_to_dut',
+           'mock_peer_switch_loopback_ip', 'mock_server_base_ip_addr']
+
+logger = logging.getLogger(__name__)
+
+'''
+Fixtures and helper methods to configure a single ToR testbed to mock the standby or active ToR in a dual ToR testbed
+
+Test functions wishing to apply the full mock config must use the following fixtures:
+    - apply_mock_dual_tor_tables
+    - apply_mock_dual_tor_kernel_configs
+    - apply_active_state_to_orchagent OR apply_standby_state_to_orchagent
+'''
+
+def _apply_config_to_swss(dut, swss_config_str, swss_filename='swss_config_file'):
+    '''
+    Applies a given configuration string to the SWSS container
+
+    Args:
+        dut: DUT object
+        swss_config_str: String containing the configuration to be applied
+        swss_filename: The filename to use for copying the config file around (default='swss_config_file')
+    '''
+
+    dut_filename = os.path.join('/tmp',swss_filename)
+
+    dut.shell('echo "{}" > {}'.format(swss_config_str, dut_filename))
+    dut.shell('docker cp {} swss:{}'.format(dut_filename, swss_filename))
+    dut.shell('docker exec swss sh -c "swssconfig {}"'.format(swss_filename))
+
+
+def _apply_dual_tor_state_to_orchagent(dut, state):
+    '''
+    Helper function to configure active/standby state in orchagent
+
+    Args:
+        dut: DUT object
+        state: either 'active' or 'standby'
+    '''
+
+    logger.info("Applying {} state to orchagent".format(state))
+
+    vlan_intfs = sorted(dut.get_vlan_intfs(), key=lambda intf: int(intf.replace('Ethernet', '')))
+
+    intf_configs = []
+
+    for intf in vlan_intfs:
+        '''
+        For each VLAN interface, create one configuration to be applied to orchagent
+        Each interface configuration has the following structure:
+
+        {
+            "MUX_CABLE_TABLE:<intf name>": {
+                "state": <active/standby>
+            }
+            "OP": "SET"
+        }
+        '''
+        intf_config_dict = {}
+        state_dict = {}
+
+        state_key = '"MUX_CABLE_TABLE:{}"'.format(intf)
+        state_dict = {'"state"': '"{}"'.format(state)}
+        intf_config_dict[state_key] = state_dict
+        intf_config_dict['"OP"'] = '"SET"'
+
+        intf_configs.append(intf_config_dict)
+
+    swss_config_str = json.dumps(intf_configs, indent=4)
+    logger.debug('SWSS config string is {}'.format(swss_config_str))
+    swss_filename = '/mux{}.json'.format(state)
+    _apply_config_to_swss(dut, swss_config_str, swss_filename)
+
+    yield
+    logger.info("Removing {} state from orchagent".format(state))
+
+    for i in range(len(intf_configs)):
+        intf_configs[i]['"OP"'] = '"DEL"'
+
+    swss_config_str = json.dumps(intf_configs, indent=4)
+    swss_filename = '/mux{}.json'.format(state)
+    _apply_config_to_swss(dut, swss_config_str, swss_filename)
+
+
+@pytest.fixture(scope='module')
+def apply_active_state_to_orchagent(duthosts, rand_one_dut_hostname):
+    dut = duthosts[rand_one_dut_hostname] 
+
+    for func in _apply_dual_tor_state_to_orchagent(dut, 'active'):
+        yield func
+
+
+@pytest.fixture(scope='module')
+def apply_standby_state_to_orchagent(duthosts, rand_one_dut_hostname):
+    dut = duthosts[rand_one_dut_hostname]
+
+    for func in _apply_dual_tor_state_to_orchagent(dut, 'standby'):
+        yield func
+
+
+@pytest.fixture(scope='module')
+def mock_peer_switch_loopback_ip(duthosts, rand_one_dut_hostname):
+    '''
+    Returns the mocked peer switch loopback IP
+
+    The peer switch loopback is always the next IP address after the DUT loopback
+
+    Returns:
+        IPv4Interface object
+    '''
+
+    dut = duthosts[rand_one_dut_hostname]
+    lo_facts = dut.get_running_config_facts()['LOOPBACK_INTERFACE']
+    loopback_intf = list(lo_facts.keys())[0]
+
+    peer_ipv4_loopback = None
+
+    for ip_addr_str in lo_facts[loopback_intf]:
+        ip_addr = ip_interface(ip_addr_str)
+
+        if type(ip_addr) is IPv4Interface:
+            peer_ipv4_loopback = ip_addr + 1
+
+    logger.debug("Mocked peer switch loopback is {}".format(peer_ipv4_loopback))
+    return peer_ipv4_loopback
+
+
+@pytest.fixture(scope='module')
+def mock_server_base_ip_addr(duthosts, rand_one_dut_hostname):
+    '''
+    Calculates the IP address of the first server
+
+    These base addresses are always the next IPs after the VLAN address
+
+    Returns:
+        IPv4Interface and IPv6 interface objects reperesenting the first server addresses
+    '''
+    dut = duthosts[rand_one_dut_hostname]
+    vlan_interface = dut.get_running_config_facts()['VLAN_INTERFACE']
+
+    vlan = list(vlan_interface.keys())[0]
+
+    server_ipv4_base_addr = None
+    server_ipv6_base_addr = None
+
+    for ip_addr_str in vlan_interface[vlan].keys():
+        ip_addr = ip_interface(ip_addr_str)
+
+        if type(ip_addr) is IPv4Interface:
+            server_ipv4_base_addr = ip_addr + 1
+        elif type(ip_addr) is IPv6Interface:
+            server_ipv6_base_addr = ip_addr + 1
+
+    logger.debug("Mocked server IP base addresses are: {} and {}".format(server_ipv4_base_addr, server_ipv6_base_addr))
+    return server_ipv4_base_addr, server_ipv6_base_addr
+
+
+@pytest.fixture(scope='module')
+def apply_dual_tor_neigh_entries(duthosts, rand_one_dut_hostname, ptfadapter, tbinfo, mock_server_base_ip_addr):
+    '''
+    Apply neighber table entries for servers
+    '''
+    logger.info("Applying dual ToR neighbor entries")
+
+    dut = duthosts[rand_one_dut_hostname]
+
+    server_ipv4_base_addr, _ = mock_server_base_ip_addr
+
+    server_ip_to_mac_map = {}
+
+    vlan_intfs = sorted(dut.get_vlan_intfs(), key=lambda intf: int(intf.replace('Ethernet', '')))
+    dut_ptf_intf_map = dut.get_extended_minigraph_facts(tbinfo)['minigraph_ptf_indices']
+
+    for i, intf in enumerate(vlan_intfs):
+        # For each VLAN interface, get the corresponding PTF interface MAC
+        ptf_port_index = dut_ptf_intf_map[intf]
+        ptf_mac = ptfadapter.dataplane.ports[(0, ptf_port_index)].mac()
+        server_ip_to_mac_map[server_ipv4_base_addr.ip + i] = ptf_mac
+
+    vlan_interface = dut.get_running_config_facts()['VLAN_INTERFACE']
+    vlan = list(vlan_interface.keys())[0]
+
+    for ip, mac in server_ip_to_mac_map.items():
+        # Use `ip neigh replace` in case entries already exist for the target IP
+        # If there are no pre-existing entries, equivalent to `ip neigh add`
+        dut.shell('ip -4 neigh replace {} lladdr {} dev {}'.format(ip, mac, vlan))
+
+    yield
+
+    logger.info("Removing dual ToR neighbor entries")
+
+    for ip in server_ip_to_mac_map.keys():
+        dut.shell('ip -4 neigh del {} dev {}'.format(ip, vlan))
+
+
+@pytest.fixture(scope='module')
+def apply_dual_tor_peer_switch_route(duthosts, rand_one_dut_hostname, mock_peer_switch_loopback_ip):
+    '''
+    Apply the tunnel route to reach the peer switch via the T1 switches
+    '''
+    logger.info("Applying dual ToR peer switch loopback route")
+    dut = duthosts[rand_one_dut_hostname]
+    bgp_neighbors = dut.bgp_facts()['ansible_facts']['bgp_neighbors'].keys()
+    
+    ipv4_neighbors = []
+
+    for neighbor in bgp_neighbors:
+        neighbor_ip = ip_address(neighbor)
+
+        if type(neighbor_ip) is IPv4Address:
+            ipv4_neighbors.append(neighbor)
+
+    nexthop_str = ''
+    for neighbor in ipv4_neighbors:
+        nexthop_str += 'nexthop via {} '.format(neighbor)
+
+    # Use `ip route replace` in case a rule already exists for this IP
+    # If there are no pre-existing routes, equivalent to `ip route add`
+    dut.shell('ip route replace {} {}'.format(mock_peer_switch_loopback_ip, nexthop_str))
+
+    yield
+
+    logger.info("Removing dual ToR peer switch loopback route")
+
+    dut.shell('ip route del {}'.format(mock_peer_switch_loopback_ip))
+
+
+@pytest.fixture(scope='module')
+def apply_peer_switch_table_to_dut(duthosts, rand_one_dut_hostname, mock_peer_switch_loopback_ip):
+    '''
+    Adds the PEER_SWITCH table to config DB
+    '''
+    logger.info("Applying PEER_SWITCH table")
+    dut = duthosts[rand_one_dut_hostname]
+    peer_switch_key = 'PEER_SWITCH|switch_hostname'
+
+    dut.shell('redis-cli -n 4 HSET "{}" "address_ipv4" "{}"'.format(peer_switch_key, mock_peer_switch_loopback_ip))
+
+    yield 
+    logger.info("Removing peer switch table")
+
+    dut.shell('redis-cli -n 4 DEL "{}"'.format(peer_switch_key))
+
+
+@pytest.fixture(scope='module')
+def apply_tunnel_table_to_dut(duthosts, rand_one_dut_hostname, mock_peer_switch_loopback_ip):
+    '''
+    Adds the TUNNEL table to config DB
+    '''
+    logger.info("Applying TUNNEL table")
+    dut = duthosts[rand_one_dut_hostname]
+
+    dut_loopback = (mock_peer_switch_loopback_ip - 1).ip
+
+    tunnel_key = 'TUNNEL|MuxTunnel0'
+    tunnel_params = {
+        'dscp_mode': 'uniform',
+        'dst_ip': dut_loopback,
+        'ecn_mode': 'copy_from_outer',
+        'encap_ecn_mode': 'standard',
+        'ttl_mode': 'pipe',
+        'tunnel_type': 'IPINIP'
+    }
+
+    for param, value in tunnel_params.items():
+        dut.shell('redis-cli -n 4 HSET "{}" "{}" "{}"'.format(tunnel_key, param, value))
+
+    yield
+    logger.info("Removing tunnel table")
+
+    dut.shell('redis-cli -n 4 DEL "{}"'.format(tunnel_key))
+
+
+@pytest.fixture(scope='module')
+def apply_mux_cable_table_to_dut(duthosts, rand_one_dut_hostname, mock_server_base_ip_addr):
+    '''
+    Adds the MUX_CABLE table to config DB
+    '''
+    logger.info("Applying MUX_CABLE table")
+    dut = duthosts[rand_one_dut_hostname]
+
+    server_ipv4_base_addr, server_ipv6_base_addr = mock_server_base_ip_addr
+
+    vlan_intfs = sorted(dut.get_vlan_intfs(), key=lambda intf: int(intf.replace('Ethernet', '')))
+
+    keys_inserted = []
+
+    for i, intf in enumerate(vlan_intfs):
+        server_ipv4 = str(server_ipv4_base_addr + i)
+        server_ipv6 = str(server_ipv6_base_addr + i)
+        key = 'MUX_CABLE|{}'.format(intf)
+        keys_inserted.append(key)
+
+        dut.shell('redis-cli -n 4 HSET "{}" "server_ipv4" "{}"'.format(key, server_ipv4))
+        dut.shell('redis-cli -n 4 HSET "{}" "server_ipv6" "{}"'.format(key, server_ipv6))
+        dut.shell('redis-cli -n 4 HSET "{}" "state" "auto"'.format(key))
+
+    yield
+    logger.info("Removing mux cable table")
+
+    for key in keys_inserted:
+        dut.shell('redis-cli -n 4 DEL "{}"'.format(key))
+
+
+@pytest.fixture(scope='module')
+def apply_mock_dual_tor_tables(apply_mux_cable_table_to_dut, apply_tunnel_table_to_dut, apply_peer_switch_table_to_dut):
+    '''
+    Wraps all table fixtures for convenience
+    '''
+    logger.info("Done applying database tables for dual ToR mock")
+
+
+@pytest.fixture(scope='module')
+def apply_mock_dual_tor_kernel_configs(apply_dual_tor_peer_switch_route, apply_dual_tor_neigh_entries):
+    '''
+    Wraps all kernel related (routes and neighbor entries) fixtures for convenience
+    '''
+    logger.info("Done applying kernel configs for dual ToR mock")