[copp] Convert COPP test to pytest (sonic-net#1633)

Signed-off-by: Danny Allen <[email protected]>

tests/common/devices.py

@@ -544,6 +544,16 @@ def check_bgp_session_nsf(self, neighbor_ip):
                 return True
         return False
 
+    def get_version(self):
+        """
+            Gets the SONiC version this device is running.
+
+            Returns:
+                str: the firmware version number (e.g. 20181130.31)
+        """
+        output = dut.command("sonic-cfggen -y /etc/sonic/sonic_version.yml -v build_version")
+        return output["stdout_lines"][0].strip()
+
 class EosHost(AnsibleHostBase):
     """
     @summary: Class for Eos switch

tests/copp/conftest.py

@@ -0,0 +1,31 @@
+"""
+    Pytest configuration used by the COPP tests.
+"""
+
+def pytest_addoption(parser):
+    """
+        Adds options to pytest that are used by the COPP tests.
+    """
+
+    parser.addoption(
+        "--nn_target_port",
+        action="store",
+        type=int,
+        default=3,
+        help="Which port to send traffic to",
+    )
+
+    parser.addoption(
+        "--pkt_tx_count",
+        action="store",
+        type=int,
+        default=100000,
+        help="How many packets to send to the DUT"
+    )
+
+    parser.addoption(
+        "--swap_syncd",
+        action="store_true",
+        default=False,
+        help="Install syncd RPC image for this test case"
+    )

tests/copp/copp_utils.py

@@ -0,0 +1,118 @@
+"""
+    Helpful utilities for writing tests for the COPP feature.
+
+    Todo:
+        Refactor ptfadapter so it can be leveraged in these test cases.
+"""
+
+DEFAULT_NN_TARGET_PORT = 3
+
+_REMOVE_IP_SCRIPT = "scripts/remove_ip.sh"
+_ADD_IP_SCRIPT = "scripts/add_ip.sh"
+_UPDATE_COPP_SCRIPT = "copp/scripts/update_copp_config.py"
+
+_BASE_COPP_CONFIG = "/tmp/00-copp.config.json"
+_SWSS_COPP_CONFIG = "swss:/etc/swss/config.d/00-copp.config.json"
+_TEMP_COPP_CONFIG = "/tmp/copp_config.json"
+
+_PTF_NN_TEMPLATE = "templates/ptf_nn_agent.conf.ptf.j2"
+_PTF_NN_DEST = "/etc/supervisor/conf.d/ptf_nn_agent.conf"
+
+_SYNCD_NN_TEMPLATE = "templates/ptf_nn_agent.conf.dut.j2"
+_SYNCD_NN_DEST = "/tmp/ptf_nn_agent.conf"
+
+def limit_policer(dut, pps_limit):
+    """
+        Updates the COPP configuration in the SWSS container to respect a given rate limit.
+
+        Note:
+            The SWSS container must be restarted for the config change to take effect.
+
+        Args:
+            dut (SonicHost): The target device.
+            pps_limit (int): The rate limit for COPP to enforce on ALL trap groups.
+    """
+
+    dut.command("docker cp {} {}".format(_SWSS_COPP_CONFIG, _BASE_COPP_CONFIG))
+    dut.script(cmd="{} {} {} {}".format(_UPDATE_COPP_SCRIPT, pps_limit,
+                                        _BASE_COPP_CONFIG, _TEMP_COPP_CONFIG))
+    dut.command("docker cp {} {}".format(_TEMP_COPP_CONFIG, _SWSS_COPP_CONFIG))
+
+def restore_policer(dut):
+    """
+        Reloads the default COPP configuration in the SWSS container.
+
+        Notes:
+            This method should only be used after limit_policer.
+
+            The SWSS container must be restarted for the config change to take effect.
+    """
+    dut.command("docker cp {} {}".format(_BASE_COPP_CONFIG, _SWSS_COPP_CONFIG))
+
+def configure_ptf(ptf, nn_target_port):
+    """
+        Configures the PTF to run the NN agent on the specified port.
+
+        Args:
+            ptf (PTFHost): The target PTF.
+            nn_target_port (int): The port to run NN agent on.
+    """
+
+    ptf.script(cmd=_REMOVE_IP_SCRIPT)
+    ptf.script(cmd=_ADD_IP_SCRIPT)
+
+    facts = {"nn_target_port": nn_target_port}
+    ptf.host.options['variable_manager'].extra_vars.update(facts)
+    ptf.template(src=_PTF_NN_TEMPLATE, dest=_PTF_NN_DEST)
+
+    ptf.supervisorctl(name="ptf_nn_agent", state="restarted")
+
+    ptf.copy(src="ptftests", dest="/root")
+
+def restore_ptf(ptf):
+    """
+        Restores the PTF and the NN agent to default settings.
+
+        Args:
+            ptf (PTFHost): The target PTF.
+    """
+
+    ptf.script(cmd=_REMOVE_IP_SCRIPT)
+
+    facts = {"nn_target_port": DEFAULT_NN_TARGET_PORT}
+    ptf.host.options['variable_manager'].extra_vars.update(facts)
+
+    ptf.template(src=_PTF_NN_TEMPLATE, dest=_PTF_NN_DEST)
+
+    ptf.supervisorctl(name="ptf_nn_agent", state="restarted")
+
+def configure_syncd(dut, nn_target_port):
+    """
+        Configures syncd to run the NN agent on the specified port.
+
+        Note:
+            The DUT must be running an RPC syncd image in order for the
+            NN agent to be available.
+
+        Args:
+            dut (SonicHost): The target device.
+            nn_target_port (int): The port to run NN agent on.
+    """
+
+    facts = {"nn_target_port": nn_target_port,
+             "nn_target_interface": _map_port_number_to_interface(dut, nn_target_port)}
+    dut.host.options['variable_manager'].extra_vars.update(facts)
+
+    dut.template(src=_SYNCD_NN_TEMPLATE, dest=_SYNCD_NN_DEST)
+    dut.command("docker cp {} syncd:/etc/supervisor/conf.d/".format(_SYNCD_NN_DEST))
+
+    dut.command("docker exec syncd supervisorctl reread")
+    dut.command("docker exec syncd supervisorctl update")
+
+def _map_port_number_to_interface(dut, nn_target_port):
+    """
+        Retrieves the correct interface for a given port number.
+    """
+
+    interfaces = dut.command("portstat")["stdout_lines"][2:]
+    return interfaces[nn_target_port].split()[0]

tests/copp/scripts/update_copp_config.py

@@ -0,0 +1,53 @@
+#!/usr/bin/python
+"""
+    Script to modify a COPP configuration to follow a specified rate limit.
+
+    This is used by the COPP tests to reduce the rate limit below that of the
+    PTF host's sending rate.
+
+    Example::
+
+        $ python update_copp_config.py <rate limit in pps> <input file> <output file>
+        $ python update_copp_config.py 600 /tmp/copp_config.json /tmp/new_copp_config.json
+"""
+import json
+import sys
+
+def generate_limited_pps_config(pps_limit, input_config_file, output_config_file):
+    """
+        Modifies a COPP config to use the specified rate limit.
+
+        Notes:
+            This only affects COPP policies that enforce a rate limit. Other
+            policies are left alone.
+
+        Args:
+            pps_limit (int): The rate limit to enforce expressed in PPS (packets-per-second)
+            input_config_file (str): The name of the file containing the initial config
+            output_config_file (str): The name of the file to output the modified config
+    """
+
+    with open(input_config_file) as input_stream:
+        copp_config = json.load(input_stream)
+
+    for trap_group in copp_config:
+        for _, group_config in trap_group.items():
+            # Notes:
+            # CIR (committed information rate) - bandwidth limit set by the policer
+            # CBS (committed burst size) - largest burst of packets allowed by the policer
+            #
+            # Setting these two values to pps_limit restricts the policer to allowing exactly
+            # that number of packets per second, which is what we want for our tests.
+
+            if "cir" in group_config:
+                group_config["cir"] = pps_limit
+
+            if "cbs" in group_config:
+                group_config["cbs"] = pps_limit
+
+    with open(output_config_file, "w+") as output_stream:
+        json.dump(copp_config, output_stream)
+
+if __name__ == "__main__":
+    ARGS = sys.argv[1:]
+    generate_limited_pps_config(ARGS[0], ARGS[1], ARGS[2])