# 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