import errno import fcntl import getpass import os import re import select import subprocess import sys from django.core.management.base import CommandError def check_root(func): """ Function decorator that checks if user has root permissions """ def wrapped(*args, **kwargs): if getpass.getuser() != 'root': cmd_name = func.__module__.split('.')[-1] msg = "Sorry, '%s' must be executed as a superuser (root)" raise CommandError(msg % cmd_name) return func(*args, **kwargs) return wrapped class _Attribute(object): """ Simple string subclass to allow arbitrary attribute access. """ def __init__(self, stdout): self.stdout = stdout def make_async(fd): """ Helper function to add the O_NONBLOCK flag to a file descriptor """ fcntl.fcntl(fd, fcntl.F_SETFL, fcntl.fcntl(fd, fcntl.F_GETFL) | os.O_NONBLOCK) def read_async(fd): """ Helper function to read some data from a file descriptor, ignoring EAGAIN errors """ try: return fd.read() except IOError as e: if e.errno != errno.EAGAIN: raise e else: return '' def runiterator(command, display=False, error_codes=[0], silent=False, stdin=''): """ Subprocess wrapper for running commands concurrently """ if display: sys.stderr.write("\n\033[1m $ %s\033[0m\n" % command) p = subprocess.Popen(command, shell=True, executable='/bin/bash', stdout=subprocess.PIPE, stderr=subprocess.PIPE, stdin=subprocess.PIPE) p.stdin.write(stdin) p.stdin.close() yield make_async(p.stdout) make_async(p.stderr) # Async reading of stdout and sterr while True: stdout = b'' stderr = b'' # Get complete unicode chunks select.select([p.stdout, p.stderr], [], []) stdoutPiece = read_async(p.stdout) stderrPiece = read_async(p.stderr) stdout += (stdoutPiece or b'') #.decode('ascii'), errors='replace') stderr += (stderrPiece or b'') #.decode('ascii'), errors='replace') if display and stdout: sys.stdout.write(stdout) if display and stderr: sys.stderr.write(stderr) state = _Attribute(stdout) state.stderr = stderr state.return_code = p.poll() yield state if state.return_code != None: p.stdout.close() p.stderr.close() raise StopIteration def run(command, display=False, error_codes=[0], silent=False, stdin='', async=False): iterator = runiterator(command, display, error_codes, silent, stdin) next(iterator) if async: return iterator stdout = b'' stderr = b'' for state in iterator: stdout += state.stdout stderr += state.stderr return_code = state.return_code out = _Attribute(stdout.strip()) err = stderr.strip() out.failed = False out.return_code = return_code out.stderr = err if return_code not in error_codes: out.failed = True msg = "\nrun() encountered an error (return code %s) while executing '%s'\n" msg = msg % (return_code, command) if display: sys.stderr.write("\n\033[1;31mCommandError: %s %s\033[m\n" % (msg, err)) if not silent: raise CommandError("%s %s %s" % (msg, err, out)) out.succeeded = not out.failed return out def sshrun(addr, command, *args, **kwargs): command = command.replace("'", """'"'"'""") cmd = "ssh -o stricthostkeychecking=no -C root@%s '%s'" % (addr, command) return run(cmd, *args, **kwargs) def get_default_celeryd_username(): """ Introspect celeryd defaults file in order to get its username """ user = None try: with open('/etc/default/celeryd') as celeryd_defaults: for line in celeryd_defaults.readlines(): if 'CELERYD_USER=' in line: user = re.findall('"([^"]*)"', line)[0] finally: if user is None: raise CommandError("Can not find the default celeryd username") return user