|
| 1 | +import os |
| 2 | +import re |
| 3 | +import subprocess |
| 4 | +import threading |
| 5 | +import time |
| 6 | +from shutil import which |
| 7 | +from typing import Any, Final, Optional |
| 8 | + |
| 9 | +from overrides import overrides |
| 10 | + |
| 11 | +from ark_sdk_python.common.connections.ark_connection import ArkConnection |
| 12 | +from ark_sdk_python.common.connections.ssh.ark_ssh_connection import SSH_PORT |
| 13 | +from ark_sdk_python.models import ArkException |
| 14 | +from ark_sdk_python.models.common.connections import ArkConnectionCommand, ArkConnectionDetails, ArkConnectionResult |
| 15 | + |
| 16 | + |
| 17 | +class ArkPTYSSHWinConnection(ArkConnection): |
| 18 | + __ANSI_COLOR_STRIPPER: Final[Any] = re.compile(r'\x1b[^m]*m|\x1b\[\?2004[hl]') |
| 19 | + __ANSI_ESCAPE_STRIPPER: Final[Any] = re.compile(r'\x1B\[[0-?]*[ -/]*[@-~]') |
| 20 | + __PROMPT_REGEX: Final[Any] = re.compile(r"[#$]") |
| 21 | + __PASSWORD_PROMPT_REGEX: Final[Any] = re.compile( |
| 22 | + r"(?i)(?:password:)|(?:passphrase for key)|(?:^Please enter your password[\s\S]+.+ >:$)" |
| 23 | + ) |
| 24 | + __EXIT_MAKRER: Final[str] = '__ARK_RC_MARK__' |
| 25 | + __DEFAULT_COL_SIZE: Final[int] = 80 |
| 26 | + __DEFAULT_ROW_SIZE: Final[int] = 24 |
| 27 | + __DEFAULT_NONEAGER_TIMEOEUT: Final[float] = 1.0 |
| 28 | + __DEFAULT_PROMPT_OVERALL_TIMEOUT: Final[float] = 20.0 |
| 29 | + __CHAR_SLEEP_TIME: Final[float] = 0.05 |
| 30 | + |
| 31 | + def __init__(self): |
| 32 | + super().__init__() |
| 33 | + self.__is_connected: bool = False |
| 34 | + self.__is_suspended: bool = False |
| 35 | + self.__pty: Optional[Any] = None |
| 36 | + self.__output_lock: threading.Lock = threading.Lock() |
| 37 | + self.__buffer: str = '' |
| 38 | + |
| 39 | + def __strip_ansi(self, ansi_input: str) -> str: |
| 40 | + ansi_input = ansi_input.strip() |
| 41 | + ansi_input = ArkPTYSSHWinConnection.__ANSI_COLOR_STRIPPER.sub('', ansi_input) |
| 42 | + ansi_input = ArkPTYSSHWinConnection.__ANSI_ESCAPE_STRIPPER.sub('', ansi_input) |
| 43 | + return ansi_input |
| 44 | + |
| 45 | + def __reset_buffer(self) -> None: |
| 46 | + with self.__output_lock: |
| 47 | + self.__buffer = '' |
| 48 | + |
| 49 | + def __read_until_latest_prompt( |
| 50 | + self, |
| 51 | + password: Optional[str] = None, |
| 52 | + noneager_timeout: float = __DEFAULT_NONEAGER_TIMEOEUT, |
| 53 | + overall_timeout: float = __DEFAULT_PROMPT_OVERALL_TIMEOUT, |
| 54 | + login_prompt: bool = False, |
| 55 | + expected_prompt: Any = __PROMPT_REGEX, |
| 56 | + ) -> None: |
| 57 | + buffer = '' |
| 58 | + prompt_found_at = -1 |
| 59 | + start_time = time.time() |
| 60 | + noneager_start_time = start_time |
| 61 | + |
| 62 | + while True: |
| 63 | + char = self.__pty.read(1) |
| 64 | + if not char: |
| 65 | + if ArkPTYSSHWinConnection.__PASSWORD_PROMPT_REGEX.search(self.__strip_ansi(buffer)) and not password and login_prompt: |
| 66 | + raise RuntimeError(f'Password prompt with no password given [{buffer}]') |
| 67 | + if (time.time() - noneager_start_time > noneager_timeout) and prompt_found_at != -1: |
| 68 | + break |
| 69 | + if (time.time() - start_time) > overall_timeout and prompt_found_at == -1: |
| 70 | + raise RuntimeError(f'Timeout while waiting for prompt [{buffer}]') |
| 71 | + time.sleep(ArkPTYSSHWinConnection.__CHAR_SLEEP_TIME) |
| 72 | + continue |
| 73 | + |
| 74 | + buffer += char |
| 75 | + |
| 76 | + with self.__output_lock: |
| 77 | + self.__buffer += char |
| 78 | + |
| 79 | + if ArkPTYSSHWinConnection.__PASSWORD_PROMPT_REGEX.search(self.__strip_ansi(buffer)) and login_prompt: |
| 80 | + if not password: |
| 81 | + raise RuntimeError(f'Password prompt with no password given [{buffer}]') |
| 82 | + self.__pty.write(password + '\n') |
| 83 | + buffer = "" |
| 84 | + prompt_found_at = -1 |
| 85 | + continue |
| 86 | + |
| 87 | + if expected_prompt.search(buffer): |
| 88 | + prompt_found_at = len(buffer) |
| 89 | + |
| 90 | + noneager_start_time = time.time() |
| 91 | + |
| 92 | + if prompt_found_at != -1: |
| 93 | + with self.__output_lock: |
| 94 | + self.__buffer = buffer |
| 95 | + |
| 96 | + @overrides |
| 97 | + def connect(self, connection_details: ArkConnectionDetails) -> None: |
| 98 | + """ |
| 99 | + Performs SSH connection with given details or keys |
| 100 | + Saves the ssh session to be used for command executions |
| 101 | + Done using windows pty |
| 102 | +
|
| 103 | + Args: |
| 104 | + connection_details (ArkConnectionDetails): _description_ |
| 105 | +
|
| 106 | + Raises: |
| 107 | + ArkException: _description_ |
| 108 | + """ |
| 109 | + # pylint: disable=import-error |
| 110 | + import winpty |
| 111 | + |
| 112 | + if self.__is_connected: |
| 113 | + return |
| 114 | + |
| 115 | + address = connection_details.address |
| 116 | + user = connection_details.credentials.user |
| 117 | + port = connection_details.port or SSH_PORT |
| 118 | + password = None |
| 119 | + key_path = None |
| 120 | + if connection_details.credentials.password: |
| 121 | + password = connection_details.credentials.password.get_secret_value() |
| 122 | + elif connection_details.credentials.private_key_filepath: |
| 123 | + key_path = connection_details.credentials.private_key_filepath |
| 124 | + |
| 125 | + ssh_args = [f'{user}@{address}', '-p', str(port), '-o', 'StrictHostKeyChecking=no'] |
| 126 | + if key_path: |
| 127 | + ssh_args.extend(['-i', str(key_path)]) |
| 128 | + try: |
| 129 | + self.__pty = winpty.PTY( |
| 130 | + cols=ArkPTYSSHWinConnection.__DEFAULT_COL_SIZE, |
| 131 | + rows=ArkPTYSSHWinConnection.__DEFAULT_ROW_SIZE, |
| 132 | + backend=winpty.enums.Backend.WinPTY, |
| 133 | + ) |
| 134 | + ssh_full_cmd = which('ssh', path=os.environ.get('PATH', os.defpath)) |
| 135 | + self.__pty.spawn(ssh_full_cmd, cmdline=' ' + subprocess.list2cmdline(ssh_args)) |
| 136 | + self.__read_until_latest_prompt(password, login_prompt=True) |
| 137 | + self.__is_connected = True |
| 138 | + except Exception as ex: |
| 139 | + raise ArkException(f'Failed to ssh connect [{str(ex)}]') from ex |
| 140 | + |
| 141 | + @overrides |
| 142 | + def disconnect(self) -> None: |
| 143 | + """ |
| 144 | + Disconnects the ssh session |
| 145 | + """ |
| 146 | + if self.__pty: |
| 147 | + self.__pty.write('exit\n') |
| 148 | + self.__pty = None |
| 149 | + self.__is_connected = False |
| 150 | + self.__is_suspended = False |
| 151 | + |
| 152 | + @overrides |
| 153 | + def suspend_connection(self) -> None: |
| 154 | + """ |
| 155 | + Suspends execution of ssh commands |
| 156 | + """ |
| 157 | + self.__is_suspended = True |
| 158 | + |
| 159 | + @overrides |
| 160 | + def restore_connection(self) -> None: |
| 161 | + """ |
| 162 | + Restores execution of ssh commands |
| 163 | + """ |
| 164 | + self.__is_suspended = False |
| 165 | + |
| 166 | + @overrides |
| 167 | + def is_suspended(self) -> bool: |
| 168 | + """ |
| 169 | + Checks whether ssh commands can be executed or not |
| 170 | +
|
| 171 | + Returns: |
| 172 | + bool: _description_ |
| 173 | + """ |
| 174 | + return self.__is_suspended |
| 175 | + |
| 176 | + @overrides |
| 177 | + def is_connected(self) -> bool: |
| 178 | + """ |
| 179 | + Checks whether theres a ssh session connected |
| 180 | +
|
| 181 | + Returns: |
| 182 | + bool: _description_ |
| 183 | + """ |
| 184 | + return self.__is_connected |
| 185 | + |
| 186 | + @overrides |
| 187 | + def run_command(self, command: ArkConnectionCommand) -> ArkConnectionResult: |
| 188 | + """ |
| 189 | + Runs a command over ssh session via pty, returning the result accordingly |
| 190 | + stderr is not supported, only stdout is returned, and it'll contain everything including stderr |
| 191 | +
|
| 192 | + Args: |
| 193 | + command (ArkConnectionCommand): _description_ |
| 194 | +
|
| 195 | + Raises: |
| 196 | + ArkException: _description_ |
| 197 | +
|
| 198 | + Returns: |
| 199 | + ArkConnectionResult: _description_ |
| 200 | + """ |
| 201 | + if not self.__is_connected or self.__is_suspended: |
| 202 | + raise ArkException('Cannot run command while not connected or suspended') |
| 203 | + |
| 204 | + self._logger.debug(f'Running command [{command.command}]') |
| 205 | + |
| 206 | + self.__reset_buffer() |
| 207 | + self.__pty.write(command.command + "\n") |
| 208 | + self.__read_until_latest_prompt() |
| 209 | + |
| 210 | + with self.__output_lock: |
| 211 | + stdout = self.__buffer.strip() |
| 212 | + |
| 213 | + self.__reset_buffer() |
| 214 | + self.__pty.write(f'echo {ArkPTYSSHWinConnection.__EXIT_MAKRER}_$?;\n') |
| 215 | + self.__read_until_latest_prompt() |
| 216 | + |
| 217 | + with self.__output_lock: |
| 218 | + lines = self.__buffer.strip().splitlines() |
| 219 | + |
| 220 | + rc = None |
| 221 | + for line in lines: |
| 222 | + line = self.__strip_ansi(line) |
| 223 | + if line.startswith(f'{ArkPTYSSHWinConnection.__EXIT_MAKRER}_'): |
| 224 | + try: |
| 225 | + rc = int(line[len(ArkPTYSSHWinConnection.__EXIT_MAKRER) + 1 :]) # +1 for the underscore |
| 226 | + break |
| 227 | + except ValueError: |
| 228 | + continue |
| 229 | + if rc is None: |
| 230 | + raise ArkException(f"Failed to parse exit code from output - [{self.__buffer}]") |
| 231 | + if rc != command.expected_rc and command.raise_on_error: |
| 232 | + raise ArkException(f'Failed to execute command [{command.command}] - [{rc}] - [{stdout}]') |
| 233 | + self._logger.debug(f'Command rc: [{rc}]') |
| 234 | + self._logger.debug(f'Command stdout: [{stdout}]') |
| 235 | + return ArkConnectionResult(stdout=stdout, rc=rc) |
0 commit comments