feat(papi): wipe remains of VAT

- Some older documentation files are not updated yet.

Change-Id: If1717e12308f0e2e76c10024e6eebe68ddeddc9f
Signed-off-by: Vratko Polak <vrpolak@cisco.com>

5 files changed, 10 insertions, 643 deletions

diff --git a/resources/libraries/python/Constants.py b/resources/libraries/python/Constants.py
index 89a302b41d..4cf6681324 100644
--- a/resources/libraries/python/Constants.py
+++ b/resources/libraries/python/Constants.py
@@ -143,9 +143,6 @@ class Constants:
     # Templates location
     RESOURCES_TPL = u"resources/templates"
 
-    # vat templates location
-    RESOURCES_TPL_VAT = u"resources/templates/vat"
-
     # Kubernetes templates location
     RESOURCES_TPL_K8S = u"resources/templates/kubernetes"
 
@@ -161,9 +158,6 @@ class Constants:
     # VPP Communications Library LD_PRELOAD library
     VCL_LDPRELOAD_LIBRARY = u"/usr/lib/x86_64-linux-gnu/libvcl_ldpreload.so"
 
-    # OpenVPP VAT binary name
-    VAT_BIN_NAME = u"vpp_api_test"
-
     # VPP service unit name
     VPP_UNIT = u"vpp"
 
diff --git a/resources/libraries/python/PapiHistory.py b/resources/libraries/python/PapiHistory.py
index 32429c4f64..18b2774908 100644
--- a/resources/libraries/python/PapiHistory.py
+++ b/resources/libraries/python/PapiHistory.py
@@ -1,4 +1,4 @@
-# Copyright (c) 2021 Cisco and/or its affiliates.
+# Copyright (c) 2023 Cisco and/or its affiliates.
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
 # You may obtain a copy of the License at:
@@ -48,7 +48,7 @@ class PapiHistory:
                 PapiHistory.reset_papi_history(node)
 
     @staticmethod
-    def add_to_papi_history(node, csit_papi_command, papi=True, **kwargs):
+    def add_to_papi_history(node, csit_papi_command, **kwargs):
         """Add command to PAPI command history on DUT node.
 
         Repr strings are used for argument values.
@@ -70,29 +70,17 @@ class PapiHistory:
         VPP Stats:
             vpp-stats(path=['^/if', '/err/ip4-input', '/sys/node/ip4-input'])
 
-        VAT:
-            sw_interface_set_flags sw_if_index 3 admin-up link-up
-
         :param node: DUT node to add command to PAPI command history for.
         :param csit_papi_command: Command to be added to PAPI command history.
-        :param papi: Says if the command to store is PAPi or VAT. Remove when
-            VAT executor is completely removed.
         :param kwargs: Optional key-value arguments.
         :type node: dict
         :type csit_papi_command: str
-        :type papi: bool
         :type kwargs: dict
         """
-        if papi:
-            args = list()
-            for key, val in kwargs.items():
-                args.append(f"{key}={val!r}")
-            item = f"{csit_papi_command}({u','.join(args)})"
-        else:
-            # This else part is here to store VAT commands.
-            # VAT history is not used.
-            # TODO: Remove when VatExecutor is completely removed.
-            item = f"{csit_papi_command}"
+        args = list()
+        for key, val in kwargs.items():
+            args.append(f"{key}={val!r}")
+        item = f"{csit_papi_command}({u','.join(args)})"
         DICT__DUTS_PAPI_HISTORY[node[u"host"]].append(item)
 
     @staticmethod
diff --git a/resources/libraries/python/SetupFramework.py b/resources/libraries/python/SetupFramework.py
index bde018a4e0..3c381166c2 100644
--- a/resources/libraries/python/SetupFramework.py
+++ b/resources/libraries/python/SetupFramework.py
@@ -1,4 +1,4 @@
-# Copyright (c) 2022 Cisco and/or its affiliates.
+# Copyright (c) 2023 Cisco and/or its affiliates.
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
 # You may obtain a copy of the License at:
@@ -259,9 +259,9 @@ def cleanup_node(node, results=None, logs=None):
 class SetupFramework:
     """Setup suite run on topology nodes.
 
-    Many VAT/CLI based tests need the scripts at remote hosts before executing
-    them. This class packs the whole testing directory and copies it over
-    to all nodes in topology under /tmp/
+    Some tests need the scripts at remote hosts before executing them.
+    This class packs the whole testing directory and copies it over
+    to all nodes in topology under /tmp/.
     """
 
     @staticmethod
diff --git a/resources/libraries/python/VatExecutor.py b/resources/libraries/python/VatExecutor.py
deleted file mode 100644
index 63f46c8b6d..0000000000
--- a/resources/libraries/python/VatExecutor.py
+++ /dev/null
@@ -1,397 +0,0 @@
-# Copyright (c) 2021 Cisco and/or its affiliates.
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at:
-#
-#     http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-"""VAT executor library."""
-
-import json
-
-from os import remove
-
-from paramiko.ssh_exception import SSHException
-from robot.api import logger
-
-import resources.libraries.python.DUTSetup as PidLib
-
-from resources.libraries.python.Constants import Constants
-from resources.libraries.python.PapiHistory import PapiHistory
-from resources.libraries.python.ssh import SSH, SSHTimeout
-
-__all__ = [u"VatExecutor"]
-
-
-def cleanup_vat_json_output(json_output, vat_name=None):
-    """Return VAT JSON output cleaned from VAT clutter.
-
-    Clean up VAT JSON output from clutter like vat# prompts and such.
-
-    :param json_output: Cluttered JSON output.
-    :param vat_name: Name of the VAT script.
-    :type json_output: JSON
-    :type vat_name: str
-    :returns: Cleaned up output JSON string.
-    :rtype: JSON
-    """
-
-    retval = json_output
-    clutter = [u"vat#", u"dump_interface_table error: Misc"]
-    if vat_name:
-        remote_file_path = f"{Constants.REMOTE_FW_DIR}/" \
-            f"{Constants.RESOURCES_TPL_VAT}/{vat_name}"
-        clutter.append(f"{remote_file_path}(2):")
-    for garbage in clutter:
-        retval = retval.replace(garbage, u"")
-    return retval
-
-
-def get_vpp_pid(node):
-    """Get PID of running VPP process.
-
-    :param node: DUT node.
-    :type node: dict
-    :returns: PID of VPP process / List of PIDs if more VPP processes are
-        running on the DUT node.
-    :rtype: int or list
-    """
-    pid = PidLib.DUTSetup.get_pid(node, u"vpp")
-    return pid
-
-
-class VatExecutor:
-    """Contains methods for executing VAT commands on DUTs."""
-    def __init__(self):
-        self._stdout = None
-        self._stderr = None
-        self._ret_code = None
-        self._script_name = None
-
-    def execute_script(
-            self, vat_name, node, timeout=120, json_out=True,
-            copy_on_execute=False, history=True):
-        """Execute VAT script on remote node, and store the result. There is an
-        option to copy script from local host to remote host before execution.
-        Path is defined automatically.
-
-        :param vat_name: Name of the vat script file. Only the file name of
-            the script is required, the resources path is prepended
-            automatically.
-        :param node: Node to execute the VAT script on.
-        :param timeout: Seconds to allow the script to run.
-        :param json_out: Require JSON output.
-        :param copy_on_execute: If true, copy the file from local host to remote
-            before executing.
-        :param history: If true, add command to history.
-        :type vat_name: str
-        :type node: dict
-        :type timeout: int
-        :type json_out: bool
-        :type copy_on_execute: bool
-        :type history: bool
-        :raises SSHException: If cannot open connection for VAT.
-        :raises SSHTimeout: If VAT execution is timed out.
-        :raises RuntimeError: If VAT script execution fails.
-        """
-        ssh = SSH()
-        try:
-            ssh.connect(node)
-        except:
-            raise SSHException(
-                f"Cannot open SSH connection to execute VAT command(s) "
-                f"from vat script {vat_name}"
-            )
-
-        if copy_on_execute:
-            ssh.scp(vat_name, vat_name)
-            remote_file_path = vat_name
-            if history:
-                with open(vat_name, u"rt") as vat_file:
-                    for line in vat_file:
-                        PapiHistory.add_to_papi_history(
-                            node, line.replace(u"\n", u""), papi=False
-                        )
-        else:
-            remote_file_path = f"{Constants.REMOTE_FW_DIR}/" \
-                f"{Constants.RESOURCES_TPL_VAT}/{vat_name}"
-
-        cmd = f"{Constants.VAT_BIN_NAME}" \
-            f"{u' json' if json_out is True else u''} " \
-            f"in {remote_file_path} script"
-        try:
-            ret_code, stdout, stderr = ssh.exec_command_sudo(
-                cmd=cmd, timeout=timeout
-            )
-        except SSHTimeout:
-            logger.error(f"VAT script execution timeout: {cmd}")
-            raise
-        except Exception:
-            raise RuntimeError(f"VAT script execution failed: {cmd}")
-
-        self._ret_code = ret_code
-        self._stdout = stdout
-        self._stderr = stderr
-        self._script_name = vat_name
-
-    def write_and_execute_script(
-            self, node, tmp_fn, commands, timeout=300, json_out=False):
-        """Write VAT commands to the script, copy it to node and execute it.
-
-        :param node: VPP node.
-        :param tmp_fn: Path to temporary file script.
-        :param commands: VAT command list.
-        :param timeout: Seconds to allow the script to run.
-        :param json_out: Require JSON output.
-        :type node: dict
-        :type tmp_fn: str
-        :type commands: list
-        :type timeout: int
-        :type json_out: bool
-        """
-        with open(tmp_fn, u"wt") as tmp_f:
-            tmp_f.writelines(commands)
-
-        self.execute_script(
-            tmp_fn, node, timeout=timeout, json_out=json_out,
-            copy_on_execute=True
-        )
-        remove(tmp_fn)
-
-    def execute_script_json_out(self, vat_name, node, timeout=120):
-        """Pass all arguments to 'execute_script' method, then cleanup returned
-        json output.
-
-        :param vat_name: Name of the vat script file. Only the file name of
-            the script is required, the resources path is prepended
-            automatically.
-        :param node: Node to execute the VAT script on.
-        :param timeout: Seconds to allow the script to run.
-        :type vat_name: str
-        :type node: dict
-        :type timeout: int
-        """
-        self.execute_script(vat_name, node, timeout, json_out=True)
-        self._stdout = cleanup_vat_json_output(self._stdout, vat_name=vat_name)
-
-    def script_should_have_failed(self):
-        """Read return code from last executed script and raise exception if the
-        script didn't fail."""
-        if self._ret_code is None:
-            raise Exception(u"First execute the script!")
-        if self._ret_code == 0:
-            raise AssertionError(
-                f"VAT Script execution passed, but failure was expected: "
-                f"{self._script_name}"
-            )
-
-    def script_should_have_passed(self):
-        """Read return code from last executed script and raise exception if the
-        script failed."""
-        if self._ret_code is None:
-            raise Exception(u"First execute the script!")
-        if self._ret_code != 0:
-            raise AssertionError(
-                f"VAT Script execution failed, but success was expected: "
-                f"{self._script_name}"
-            )
-
-    def get_script_stdout(self):
-        """Returns value of stdout from last executed script."""
-        return self._stdout
-
-    def get_script_stderr(self):
-        """Returns value of stderr from last executed script."""
-        return self._stderr
-
-    @staticmethod
-    def cmd_from_template(node, vat_template_file, json_param=True, **vat_args):
-        """Execute VAT script on specified node. This method supports
-        script templates with parameters.
-
-        :param node: Node in topology on witch the script is executed.
-        :param vat_template_file: Template file of VAT script.
-        :param json_param: Require JSON mode.
-        :param vat_args: Arguments to the template file.
-        :returns: List of JSON objects returned by VAT.
-        """
-        with VatTerminal(node, json_param=json_param) as vat:
-            return vat.vat_terminal_exec_cmd_from_template(
-                vat_template_file, **vat_args
-            )
-
-
-class VatTerminal:
-    """VAT interactive terminal.
-
-    :param node: Node to open VAT terminal on.
-    :param json_param: Defines if outputs from VAT are in JSON format.
-        Default is True.
-    :type node: dict
-    :type json_param: bool
-
-    """
-
-    __VAT_PROMPT = (u"vat# ", )
-    __LINUX_PROMPT = (u":~# ", u":~$ ", u"~]$ ", u"~]# ")
-
-    def __init__(self, node, json_param=True):
-        json_text = u" json" if json_param else u""
-        self.json = json_param
-        self._node = node
-        self._ssh = SSH()
-        self._ssh.connect(self._node)
-        try:
-            self._tty = self._ssh.interactive_terminal_open()
-        except Exception:
-            raise RuntimeError(
-                f"Cannot open interactive terminal on node "
-                f"{self._node[u'host']}"
-            )
-
-        for _ in range(3):
-            try:
-                self._ssh.interactive_terminal_exec_command(
-                    self._tty, f"sudo -S {Constants.VAT_BIN_NAME}{json_text}",
-                    self.__VAT_PROMPT
-                )
-            except Exception:
-                continue
-            else:
-                break
-        else:
-            vpp_pid = get_vpp_pid(self._node)
-            if vpp_pid:
-                if isinstance(vpp_pid, int):
-                    logger.trace(f"VPP running on node {self._node[u'host']}")
-                else:
-                    logger.error(
-                        f"More instances of VPP running "
-                        f"on node {self._node[u'host']}."
-                    )
-            else:
-                logger.error(f"VPP not running on node {self._node[u'host']}.")
-            raise RuntimeError(
-                f"Failed to open VAT console on node {self._node[u'host']}"
-            )
-
-        self._exec_failure = False
-        self.vat_stdout = None
-
-    def __enter__(self):
-        return self
-
-    def __exit__(self, exc_type, exc_val, exc_tb):
-        self.vat_terminal_close()
-
-    def vat_terminal_exec_cmd(self, cmd):
-        """Execute command on the opened VAT terminal.
-
-        :param cmd: Command to be executed.
-
-        :returns: Command output in python representation of JSON format or
-            None if not in JSON mode.
-        """
-        PapiHistory.add_to_papi_history(self._node, cmd, papi=False)
-        logger.debug(f"Executing command in VAT terminal: {cmd}")
-        try:
-            out = self._ssh.interactive_terminal_exec_command(
-                self._tty, cmd, self.__VAT_PROMPT
-            )
-            self.vat_stdout = out
-        except Exception:
-            self._exec_failure = True
-            vpp_pid = get_vpp_pid(self._node)
-            if vpp_pid:
-                if isinstance(vpp_pid, int):
-                    msg = f"VPP running on node {self._node[u'host']} " \
-                        f"but VAT command {cmd} execution failed."
-                else:
-                    msg = f"More instances of VPP running on node " \
-                        f"{self._node[u'host']}. VAT command {cmd} " \
-                        f"execution failed."
-            else:
-                msg = f"VPP not running on node {self._node[u'host']}. " \
-                    f"VAT command {cmd} execution failed."
-            raise RuntimeError(msg)
-
-        logger.debug(f"VAT output: {out}")
-        if self.json:
-            obj_start = out.find(u"{")
-            obj_end = out.rfind(u"}")
-            array_start = out.find(u"[")
-            array_end = out.rfind(u"]")
-
-            if obj_start == -1 and array_start == -1:
-                raise RuntimeError(f"VAT command {cmd}: no JSON data.")
-
-            if obj_start < array_start or array_start == -1:
-                start = obj_start
-                end = obj_end + 1
-            else:
-                start = array_start
-                end = array_end + 1
-            out = out[start:end]
-            json_out = json.loads(out)
-            return json_out
-
-        return None
-
-    def vat_terminal_close(self):
-        """Close VAT terminal."""
-        # interactive terminal is dead, we only need to close session
-        if not self._exec_failure:
-            try:
-                self._ssh.interactive_terminal_exec_command(
-                    self._tty, u"quit", self.__LINUX_PROMPT
-                )
-            except Exception:
-                vpp_pid = get_vpp_pid(self._node)
-                if vpp_pid:
-                    if isinstance(vpp_pid, int):
-                        logger.trace(
-                            f"VPP running on node {self._node[u'host']}."
-                        )
-                    else:
-                        logger.error(
-                            f"More instances of VPP running "
-                            f"on node {self._node[u'host']}."
-                        )
-                else:
-                    logger.error(
-                        f"VPP not running on node {self._node[u'host']}."
-                    )
-                raise RuntimeError(
-                    f"Failed to close VAT console "
-                    f"on node {self._node[u'host']}"
-                )
-        try:
-            self._ssh.interactive_terminal_close(self._tty)
-        except Exception:
-            raise RuntimeError(
-                f"Cannot close interactive terminal "
-                f"on node {self._node[u'host']}"
-            )
-
-    def vat_terminal_exec_cmd_from_template(self, vat_template_file, **args):
-        """Execute VAT script from a file.
-
-        :param vat_template_file: Template file name of a VAT script.
-        :param args: Dictionary of parameters for VAT script.
-        :returns: List of JSON objects returned by VAT.
-        """
-        file_path = f"{Constants.RESOURCES_TPL_VAT}/{vat_template_file}"
-
-        with open(file_path, u"rt") as template_file:
-            cmd_template = template_file.readlines()
-        ret = list()
-        for line_tmpl in cmd_template:
-            vat_cmd = line_tmpl.format(**args)
-            ret.append(self.vat_terminal_exec_cmd(vat_cmd.replace(u"\n", u"")))
-        return ret
diff --git a/resources/libraries/python/VatJsonUtil.py b/resources/libraries/python/VatJsonUtil.py
deleted file mode 100644
index 3e956e790d..0000000000
--- a/resources/libraries/python/VatJsonUtil.py
+++ /dev/null
@@ -1,218 +0,0 @@
-# Copyright (c) 2021 Cisco and/or its affiliates.
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at:
-#
-#     http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-"""Utilities to work with JSON data format from VAT."""
-
-from robot.api import logger
-
-from resources.libraries.python.parsers.JsonParser import JsonParser
-
-
-class VatJsonUtil:
-    """Utilities to work with JSON data format from VAT."""
-
-    @staticmethod
-    def _convert_mac_to_number_list(mac_address):
-        """Convert MAC address string to list of decimal numbers.
-
-        Converts a ":" separated MAC address to decimal number list as used
-        in JSON interface dump.
-
-        :param mac_address: MAC address.
-        :type mac_address: str
-        :returns: List representation of MAC address.
-        :rtype: list
-        """
-        list_mac = list()
-        for num in mac_address.split(u":"):
-            list_mac.append(int(num, 16))
-        return list_mac
-
-    @staticmethod
-    def get_vpp_interface_by_mac(interfaces_list, mac_address):
-        """Return interface dictionary from interface_list by MAC address.
-
-        Extracts interface dictionary from all of the interfaces in interfaces
-        list parsed from JSON according to mac_address of the interface.
-
-        :param interfaces_list: Interfaces parsed from JSON.
-        :param mac_address: MAC address of interface we are looking for.
-        :type interfaces_list: dict
-        :type mac_address: str
-        :returns: Interface from JSON.
-        :rtype: dict
-        """
-        interface_dict = dict()
-        list_mac_address = VatJsonUtil._convert_mac_to_number_list(mac_address)
-        logger.trace(
-            f"MAC address {mac_address} converted to list {list_mac_address}."
-        )
-        for interface in interfaces_list:
-            # TODO: create vat json integrity checking and move there
-            if u"l2_address" not in interface:
-                raise KeyError(
-                    u"key l2_address not found in interface dict."
-                    u"Probably input list is not parsed from correct VAT "
-                    u"json output."
-                )
-            if u"l2_address_length" not in interface:
-                raise KeyError(
-                    u"key l2_address_length not found in interface "
-                    u"dict. Probably input list is not parsed from correct "
-                    u"VAT json output."
-                )
-            mac_from_json = interface[u"l2_address"][:6]
-            if mac_from_json == list_mac_address:
-                if interface[u"l2_address_length"] != 6:
-                    raise ValueError(u"l2_address_length value is not 6.")
-                interface_dict = interface
-                break
-        return interface_dict
-
-    @staticmethod
-    def update_vpp_interface_data_from_json(node, interface_dump_json):
-        """Update vpp node data in node__DICT from JSON interface dump.
-
-        This method updates vpp interface names and sw if indexes according to
-        interface MAC addresses found in interface_dump_json.
-
-        :param node: Node dictionary.
-        :param interface_dump_json: JSON output from dump_interface_list VAT
-            command.
-        :type node: dict
-        :type interface_dump_json: str
-        """
-        interface_list = JsonParser().parse_data(interface_dump_json)
-        for ifc in node[u"interfaces"].values():
-            if_mac = ifc[u"mac_address"]
-            interface_dict = VatJsonUtil.get_vpp_interface_by_mac(
-                interface_list, if_mac
-            )
-            if not interface_dict:
-                logger.trace(f"Interface {ifc} not found by MAC {if_mac}")
-                ifc[u"vpp_sw_index"] = None
-                continue
-            ifc[u"name"] = interface_dict[u"interface_name"]
-            ifc[u"vpp_sw_index"] = interface_dict[u"sw_if_index"]
-            ifc[u"mtu"] = interface_dict[u"mtu"]
-
-    @staticmethod
-    def get_interface_sw_index_from_json(interface_dump_json, interface_name):
-        """Get sw_if_index from given JSON output by interface name.
-
-        :param interface_dump_json: JSON output from dump_interface_list VAT
-            command.
-        :param interface_name: Interface name.
-        :type interface_dump_json: str
-        :type interface_name: str
-        :returns: SW interface index.
-        :rtype: int
-        :raises ValueError: If interface not found in interface_dump_json.
-        """
-        logger.trace(interface_dump_json)
-        interface_list = JsonParser().parse_data(interface_dump_json)
-        for interface in interface_list:
-            try:
-                if interface[u"interface_name"] == interface_name:
-                    index = interface[u"sw_if_index"]
-                    logger.debug(
-                        f"Interface with name {interface_name} "
-                        f"has sw_if_index {index}."
-                    )
-                    return index
-            except KeyError:
-                pass
-        raise ValueError(f"Interface with name {interface_name} not found.")
-
-    @staticmethod
-    def get_interface_name_from_json(interface_dump_json, sw_if_index):
-        """Get interface name from given JSON output by sw_if_index.
-
-        :param interface_dump_json: JSON output from dump_interface_list VAT
-            command.
-        :param sw_if_index: SW interface index.
-        :type interface_dump_json: str
-        :type sw_if_index: int
-        :returns: Interface name.
-        :rtype: str
-        :raises ValueError: If interface not found in interface_dump_json.
-        """
-        logger.trace(interface_dump_json)
-        interface_list = JsonParser().parse_data(interface_dump_json)
-        for interface in interface_list:
-            try:
-                if interface[u"sw_if_index"] == sw_if_index:
-                    interface_name = interface[u"interface_name"]
-                    logger.debug(
-                        f"Interface with sw_if_index {sw_if_index} "
-                        f"has name {interface_name}."
-                    )
-                    return interface_name
-            except KeyError:
-                pass
-        raise ValueError(f"Interface with sw_if_index {sw_if_index} not found.")
-
-    @staticmethod
-    def get_interface_mac_from_json(interface_dump_json, sw_if_index):
-        """Get interface MAC address from given JSON output by sw_if_index.
-
-        :param interface_dump_json: JSON output from dump_interface_list VAT
-            command.
-        :param sw_if_index: SW interface index.
-        :type interface_dump_json: str
-        :type sw_if_index: int
-        :returns: Interface MAC address.
-        :rtype: str
-        :raises ValueError: If interface not found in interface_dump_json.
-        """
-        logger.trace(interface_dump_json)
-        interface_list = JsonParser().parse_data(interface_dump_json)
-        for interface in interface_list:
-            try:
-                if interface[u"sw_if_index"] == sw_if_index:
-                    mac_from_json = interface[u"l2_address"][:6] \
-                        if u"l2_address" in list(interface.keys()) else u""
-                    mac_address = u":".join(
-                        f"{item:02x}" for item in mac_from_json
-                    )
-                    logger.debug(
-                        f"Interface with sw_if_index {sw_if_index} "
-                        f"has MAC address {mac_address}."
-                    )
-                    return mac_address
-            except KeyError:
-                pass
-        raise ValueError(f"Interface with sw_if_index {sw_if_index} not found.")
-
-    @staticmethod
-    def verify_vat_retval(vat_out, exp_retval=0, err_msg=u"VAT cmd failed"):
-        """Verify return value of VAT command.
-
-        VAT command JSON output should be object (dict in python) or array. We
-        are looking for something like this: { "retval": 0 }. Verification is
-        skipped if VAT output does not contain return value element or root
-        elemet is array.
-
-        :param vat_out: VAT command output in python representation of JSON.
-        :param exp_retval: Expected return value (default 0).
-        :err_msg: Message to be displayed in case of error (optional).
-        :type vat_out: dict or list
-        :type exp_retval: int
-        :type err_msg: str
-        :raises RuntimeError: If VAT command return value is incorrect.
-        """
-        if isinstance(vat_out, dict):
-            retval = vat_out.get(u"retval")
-            if retval is not None:
-                if retval != exp_retval:
-                    raise RuntimeError(err_msg)