[dualtor]: Mock all y_cable methods for mux sim (sonic-net#3242)

What is the motivation for this PR?
XCVRD runs some methods which attempt to read from cable hardware. This hardware doesn't exist for mux simulator, so XCVRD writes many errors to the syslog.

How did you do it?
Implement mocks for all methods in sonic_y_cable to prevent errors from being generated.

How did you verify/test it?
Inject new mux_simulator_client to dual ToR device with changes from sonic-net/sonic-platform-common#181. Verify PMON and mux containers stay up, and show mux status output looks normal. Initiate CLI switchover and confirm show mux status output reflects switchover.

Signed-off-by: Lawrence Lee <[email protected]>

tests/templates/y_cable_simulator_client.j2

@@ -13,6 +13,8 @@ VM_SET = "{{ group_name }}"
 
 DUT_NAME = "{{ dut_name }}"
 
+FLAP_COUNTER = 'flap_counter'
+
 BASE_URL = "http://{{ mux_simulator_server }}:{{ mux_simulator_port }}/"
 
 SYSLOG_IDENTIFIER = "y_cable_sim"
@@ -133,17 +135,23 @@ def _load_port_config_ini(porttabfile):
             # Next line, next host index
             host_intf_index += 1
 
-def _url(physical_port):
+def _url(physical_port, action=None):
     """
     Helper function to build an url for given physical_port
 
     Args:
         physical_port: physical port on switch, an integer starting from 1
+        action: 'flap_counter' or None
     Returns:
         str: The url for post/get.
     """
     host_intf_index = _physical_port_to_host_port(physical_port)
-    return BASE_URL + "/mux/{}/{}".format(VM_SET, host_intf_index)
+    url = BASE_URL + "/mux/{}/{}".format(VM_SET, host_intf_index)
+
+    if action:
+        url += "/{}".format(action)
+
+    return url
 
 def _post(physical_port, data):
     """
@@ -172,7 +180,7 @@ def _post(physical_port, data):
         return False
     return True
 
-def _get(physical_port):
+def _get(physical_port, action=None):
     """
     Helper function for polling status from y_cable server.
 
@@ -182,7 +190,7 @@ def _get(physical_port):
         dict: A dict decoded from server's response.
         None: Returns None is error is detected.
     """
-    req = request.Request(url=_url(physical_port))
+    req = request.Request(url=_url(physical_port, action))
     try:
         res = request.urlopen(req)
         data = res.read()
@@ -269,3 +277,125 @@ def check_if_link_is_active_for_torB(physical_port):
     """
     return True
 
+def enable_prbs_mode(physical_port, target, mode_value, lane_map):
+    """
+    Enables PRBS mode. Mocked for mux simulator.
+    """
+    return True
+
+def disable_prbs_mode(physical_port, target):
+    """
+    Disables PRBS mode. Mocked for mux simulator.
+    """
+    return True
+
+def enable_loopback_mode(physical_port, target, lane_map):
+    """
+    Enables loopback mode. Mocked for mux simulator.
+    """
+    return True
+
+def disable_loopback_mode(physical_port, target):
+    """
+    Disables loopback mode. Mocked for mux simulator.
+    """
+    return True
+
+def get_ber_info(physical_port, target):
+    """
+    Returns BER for a port. Mocked for mux simulator.
+    """
+    return [0, 0, 0, 0]
+
+def get_eye_info(physical_port, target):
+    """
+    Returns EYE for a port. Mocked for mux simulator.
+    """
+    return [0, 0, 0, 0]
+
+def get_part_number(physical_port):
+    """
+    Returns part number for port. Mocked for mux simulator.
+    """
+    return "Mux_Simulator"
+
+def get_vendor(physical_port):
+    """
+    Returns vendor for port. Mocked for mux simulator.
+    """
+    return "Microsoft"
+
+def get_switch_count(physical_port, count_type):
+    """
+    Returns switchover count for port.
+    """
+    if count_type == 'auto':
+        return 0
+    else:
+        return _get(physical_port, FLAP_COUNTER)
+
+def get_target_cursor_values(physical_port, lane, target):
+    """
+    Returns cursor equilization parameters. Mocked for mux simulator.
+    """
+    return [-1, -1, -1, -1, -1]
+
+def check_if_nic_lanes_active(physical_port):
+    """
+    Checks if NIC lanes are active. Mocked for mux simulator.
+    """
+    return 15
+
+def get_firmware_version(physical_port, target):
+    """
+    Mocked for mux simulator
+    """
+    return None
+
+def get_interval_voltage_temp(physical_port):
+    """
+    Mocked for mux simulator
+    """
+    return 1, 1
+
+def get_nic_voltage_temp(physical_port):
+    """
+    Mocked for mux simulator
+    """
+    return 1, 1
+
+def get_local_temperature(physical_port):
+    """
+    Mocked for mux simulator
+    """
+    return 1
+
+def get_local_voltage(physical_port):
+    """
+    Mocked for mux simulator
+    """
+    return 1
+
+def get_nic_temperature(physical_port):
+    """
+    Mocked for mux simulator
+    """
+    return 1
+
+def get_nic_voltage(physical_port):
+    """
+    Mocked for mux simulator
+    """
+    return 1
+
+def set_switching_mode(physical_port, mode):
+    """
+    Mocked for mux simulator
+    """
+    return True
+
+def get_switching_mode(physical_port, mode):
+    """
+    Mocked for mux simulator
+    """
+    return 1