codekingpro/portable-devtools

1"""2This module provides an interface to spawn a detached task to be3run with httpie.internal.daemon_runner on a separate process. It is4based on DVC's daemon system.5https://github.com/iterative/dvc/blob/main/dvc/daemon.py6"""7 8import inspect9import os10import platform11import sys12import httpie.__main__13from contextlib import suppress14from subprocess import Popen, DEVNULL15from typing import Dict, List16from httpie.compat import is_frozen, is_windows17 18 19ProcessContext = Dict[str, str]20 21 22def _start_process(cmd: List[str], **kwargs) -> Popen:23    prefix = [sys.executable]24    # If it is frozen, sys.executable points to the binary (http).25    # Otherwise it points to the python interpreter.26    if not is_frozen:27        main_entrypoint = httpie.__main__.__file__28        prefix += [main_entrypoint]29    return Popen(prefix + cmd, close_fds=True, shell=False, stdout=DEVNULL, stderr=DEVNULL, **kwargs)30 31 32def _spawn_windows(cmd: List[str], process_context: ProcessContext) -> None:33    from subprocess import (34        CREATE_NEW_PROCESS_GROUP,35        CREATE_NO_WINDOW,36        STARTF_USESHOWWINDOW,37        STARTUPINFO,38    )39 40    # https://stackoverflow.com/a/700642441    # https://bugs.python.org/issue4161942    creationflags = CREATE_NEW_PROCESS_GROUP | CREATE_NO_WINDOW43 44    startupinfo = STARTUPINFO()45    startupinfo.dwFlags |= STARTF_USESHOWWINDOW46 47    _start_process(48        cmd,49        env=process_context,50        creationflags=creationflags,51        startupinfo=startupinfo,52    )53 54 55def _spawn_posix(args: List[str], process_context: ProcessContext) -> None:56    """57    Perform a double fork procedure* to detach from the parent58    process so that we don't block the user even if their original59    command's execution is done but the release fetcher is not.60 61    [1]: https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap11.html#tag_11_01_0362    """63 64    from httpie.core import main65 66    try:67        pid = os.fork()68        if pid > 0:69            return70    except OSError:71        os._exit(1)72 73    os.setsid()74 75    try:76        pid = os.fork()77        if pid > 0:78            os._exit(0)79    except OSError:80        os._exit(1)81 82    # Close all standard inputs/outputs83    sys.stdin.close()84    sys.stdout.close()85    sys.stderr.close()86 87    if platform.system() == 'Darwin':88        # Double-fork is not reliable on MacOS, so we'll use a subprocess89        # to ensure the task is isolated properly.90        process = _start_process(args, env=process_context)91        # Unlike windows, since we already completed the fork procedure92        # we can simply join the process and wait for it.93        process.communicate()94    else:95        os.environ.update(process_context)96        with suppress(BaseException):97            main(['http'] + args)98 99    os._exit(0)100 101 102def _spawn(args: List[str], process_context: ProcessContext) -> None:103    """104    Spawn a new process to run the given command.105    """106    if is_windows:107        _spawn_windows(args, process_context)108    else:109        _spawn_posix(args, process_context)110 111 112def spawn_daemon(task: str) -> None:113    args = [task, '--daemon']114    process_context = os.environ.copy()115    if not is_frozen:116        file_path = os.path.abspath(inspect.stack()[0][1])117        process_context['PYTHONPATH'] = os.path.dirname(118            os.path.dirname(os.path.dirname(file_path))119        )120 121    _spawn(args, process_context)122