from __future__ import annotations import uuid import allure from tenacity import retry, stop_after_attempt, wait_fixed from typing import Optional from pytest_tests.helpers.ssh_helper import HostClient class RemoteProcess: def __init__(self, cmd: str, process_dir: str, host_client: HostClient): self.process_dir = process_dir self.cmd = cmd self.stdout_last_line_number = 0 self.stderr_last_line_number = 0 self.pid: Optional[str] = None self.proc_rc: Optional[int] = None self.saved_stdout: Optional[str] = None self.saved_stderr: Optional[str] = None self.host_client = host_client @classmethod @allure.step("Create remote process") def create(cls, command: str, host_client: HostClient) -> RemoteProcess: """ Create a process on a remote host. Created dir for process with following files: command.sh: script to execute pid: contains process id rc: contains script return code stderr: contains script errors stdout: contains script output Args: host_client: Host client instance command: command to be run on a remote host Returns: RemoteProcess instance for further examination """ remote_process = cls( cmd=command, process_dir=f"/tmp/proc_{uuid.uuid4()}", host_client=host_client ) remote_process._create_process_dir() remote_process._generate_command_script(command) remote_process._start_process() remote_process.pid = remote_process._get_pid() return remote_process @allure.step("Get process stdout") def stdout(self, full: bool = False) -> str: """ Method to get process stdout, either fresh info or full. Args: full: returns full stdout that we have to this moment Returns: Fresh stdout. By means of stdout_last_line_number only new stdout lines are returned. If process is finished (proc_rc is not None) saved stdout is returned """ if self.saved_stdout is not None: cur_stdout = self.saved_stdout else: terminal = self.host_client.exec(f"cat {self.process_dir}/stdout") if self.proc_rc is not None: self.saved_stdout = terminal.stdout cur_stdout = terminal.stdout if full: return cur_stdout whole_stdout = cur_stdout.split("\n") if len(whole_stdout) > self.stdout_last_line_number: resulted_stdout = "\n".join(whole_stdout[self.stdout_last_line_number :]) self.stdout_last_line_number = len(whole_stdout) return resulted_stdout return "" @allure.step("Get process stderr") def stderr(self, full: bool = False) -> str: """ Method to get process stderr, either fresh info or full. Args: full: returns full stderr that we have to this moment Returns: Fresh stderr. By means of stderr_last_line_number only new stderr lines are returned. If process is finished (proc_rc is not None) saved stderr is returned """ if self.saved_stderr is not None: cur_stderr = self.saved_stderr else: terminal = self.host_client.exec(f"cat {self.process_dir}/stderr") if self.proc_rc is not None: self.saved_stderr = terminal.stdout cur_stderr = terminal.stdout if full: return cur_stderr whole_stderr = cur_stderr.split("\n") if len(whole_stderr) > self.stderr_last_line_number: resulted_stderr = "\n".join(whole_stderr[self.stderr_last_line_number :]) self.stderr_last_line_number = len(whole_stderr) return resulted_stderr return "" @allure.step("Get process rc") def rc(self) -> Optional[int]: if self.proc_rc is not None: return self.proc_rc terminal = self.host_client.exec(f"cat {self.process_dir}/rc", verify=False) if "No such file or directory" in terminal.stderr: return None elif terminal.stderr or terminal.rc != 0: raise AssertionError(f"cat process rc was not successfull: {terminal.stderr}") self.proc_rc = int(terminal.stdout) return self.proc_rc @allure.step("Check if process is running") def running(self) -> bool: return self.rc() is None @allure.step("Send signal to process") def send_signal(self, signal: int) -> None: kill_res = self.host_client.exec(f"kill -{signal} {self.pid}", verify=False) if "No such process" in kill_res.stderr: return if kill_res.rc: raise AssertionError(f"Signal {signal} not sent. Return code of kill: {kill_res.rc}") @allure.step("Stop process") def stop(self) -> None: self.send_signal(15) @allure.step("Kill process") def kill(self) -> None: self.send_signal(9) @allure.step("Clear process directory") def clear(self) -> None: if self.process_dir == "/": raise AssertionError(f"Invalid path to delete: {self.process_dir}") self.host_client.exec(f"rm -rf {self.process_dir}") @allure.step("Start remote process") def _start_process(self) -> None: self.host_client.exec( f"nohup {self.process_dir}/command.sh {self.process_dir}/stdout " f"2>{self.process_dir}/stderr &" ) @allure.step("Create process directory") def _create_process_dir(self) -> None: self.host_client.exec(f"mkdir {self.process_dir}; chmod 777 {self.process_dir}") terminal = self.host_client.exec(f"realpath {self.process_dir}") self.process_dir = terminal.stdout.strip() @allure.step("Get pid") @retry(wait=wait_fixed(10), stop=stop_after_attempt(5), reraise=True) def _get_pid(self) -> str: terminal = self.host_client.exec(f"cat {self.process_dir}/pid") assert terminal.stdout, f"invalid pid: {terminal.stdout}" return terminal.stdout.strip() @allure.step("Generate command script") def _generate_command_script(self, command: str) -> None: command = command.replace('"', '\\"').replace("\\", "\\\\") script = ( f"#!/bin/bash\n" f"cd {self.process_dir}\n" f"{command} &\n" f"pid=\$!\n" f"cd {self.process_dir}\n" f"echo \$pid > {self.process_dir}/pid\n" f"wait \$pid\n" f"echo $? > {self.process_dir}/rc" ) self.host_client.exec( f'echo "{script}" > {self.process_dir}/command.sh' ) self.host_client.exec(f"cat {self.process_dir}/command.sh") self.host_client.exec(f"chmod +x {self.process_dir}/command.sh")