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# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
import codecs
import io
import itertools
import locale
import logging
import os
import sys
from collections import deque
from contextlib import contextmanager
import six
from looseversion import LooseVersion
def getpreferredencoding():
# locale._parse_localename makes locale.getpreferredencoding
# return None when LC_ALL is C, instead of e.g. 'US-ASCII' or
# 'ANSI_X3.4-1968' when it uses nl_langinfo.
encoding = None
try:
encoding = locale.getpreferredencoding()
except ValueError:
# On english OSX, LC_ALL is UTF-8 (not en-US.UTF-8), and
# that throws off locale._parse_localename, which ends up
# being used on e.g. homebrew python.
if os.environ.get("LC_ALL", "").upper() == "UTF-8":
encoding = "utf-8"
return encoding
class Version(LooseVersion):
"""A simple subclass of looseversion.LooseVersion.
Adds attributes for `major`, `minor`, `patch` for the first three
version components so users can easily pull out major/minor
versions, like:
v = Version('1.2b')
v.major == 1
v.minor == 2
v.patch == 0
"""
def __init__(self, version):
# Can't use super, LooseVersion's base class is not a new-style class.
LooseVersion.__init__(self, version)
# Take the first three integer components, stopping at the first
# non-integer and padding the rest with zeroes.
(self.major, self.minor, self.patch) = list(
itertools.chain(
itertools.takewhile(lambda x: isinstance(x, int), self.version),
(0, 0, 0),
)
)[:3]
class ConfigureOutputHandler(logging.Handler):
"""A logging handler class that sends info messages to stdout and other
messages to stderr.
Messages sent to stdout are not formatted with the attached Formatter.
Additionally, if they end with '... ', no newline character is printed,
making the next message printed follow the '... '.
Only messages above log level INFO (included) are logged.
Messages below that level can be kept until an ERROR message is received,
at which point the last `maxlen` accumulated messages below INFO are
printed out. This feature is only enabled under the `queue_debug` context
manager.
"""
def __init__(self, stdout=sys.stdout, stderr=sys.stderr, maxlen=20):
super(ConfigureOutputHandler, self).__init__()
# Python has this feature where it sets the encoding of pipes to
# ascii, which blatantly fails when trying to print out non-ascii.
def fix_encoding(fh):
if six.PY3:
return fh
try:
isatty = fh.isatty()
except AttributeError:
isatty = True
if not isatty:
encoding = getpreferredencoding()
if encoding:
return codecs.getwriter(encoding)(fh)
return fh
self._stdout = fix_encoding(stdout)
self._stderr = fix_encoding(stderr) if stdout != stderr else self._stdout
try:
fd1 = self._stdout.fileno()
fd2 = self._stderr.fileno()
self._same_output = self._is_same_output(fd1, fd2)
except (AttributeError, io.UnsupportedOperation):
self._same_output = self._stdout == self._stderr
self._stdout_waiting = None
self._debug = deque(maxlen=maxlen + 1)
self._keep_if_debug = self.THROW
self._queue_is_active = False
@staticmethod
def _is_same_output(fd1, fd2):
if fd1 == fd2:
return True
stat1 = os.fstat(fd1)
stat2 = os.fstat(fd2)
return stat1.st_ino == stat2.st_ino and stat1.st_dev == stat2.st_dev
# possible values for _stdout_waiting
WAITING = 1
INTERRUPTED = 2
# possible values for _keep_if_debug
THROW = 0
KEEP = 1
PRINT = 2
def emit(self, record):
try:
if record.levelno == logging.INFO:
stream = self._stdout
msg = six.ensure_text(record.getMessage())
if self._stdout_waiting == self.INTERRUPTED and self._same_output:
msg = " ... %s" % msg
self._stdout_waiting = msg.endswith("... ")
if msg.endswith("... "):
self._stdout_waiting = self.WAITING
else:
self._stdout_waiting = None
msg = "%s\n" % msg
elif record.levelno < logging.INFO and self._keep_if_debug != self.PRINT:
if self._keep_if_debug == self.KEEP:
self._debug.append(record)
return
else:
if record.levelno >= logging.ERROR and len(self._debug):
self._emit_queue()
if self._stdout_waiting == self.WAITING and self._same_output:
self._stdout_waiting = self.INTERRUPTED
self._stdout.write("\n")
self._stdout.flush()
stream = self._stderr
msg = "%s\n" % self.format(record)
stream.write(msg)
stream.flush()
except (KeyboardInterrupt, SystemExit, IOError):
raise
except Exception:
self.handleError(record)
@contextmanager
def queue_debug(self):
if self._queue_is_active:
yield
return
self._queue_is_active = True
self._keep_if_debug = self.KEEP
try:
yield
except Exception:
self._emit_queue()
# The exception will be handled and very probably printed out by
# something upper in the stack.
raise
finally:
self._queue_is_active = False
self._keep_if_debug = self.THROW
self._debug.clear()
def _emit_queue(self):
self._keep_if_debug = self.PRINT
if len(self._debug) == self._debug.maxlen:
r = self._debug.popleft()
self.emit(
logging.LogRecord(
r.name,
r.levelno,
r.pathname,
r.lineno,
"<truncated - see config.log for full output>",
(),
None,
)
)
while True:
try:
self.emit(self._debug.popleft())
except IndexError:
break
self._keep_if_debug = self.KEEP
class LineIO(object):
"""File-like class that sends each line of the written data to a callback
(without carriage returns).
"""
def __init__(self, callback, errors="strict"):
self._callback = callback
self._buf = ""
self._encoding = getpreferredencoding()
self._errors = errors
def write(self, buf):
buf = six.ensure_text(buf, encoding=self._encoding or "utf-8")
lines = buf.splitlines()
if not lines:
return
if self._buf:
lines[0] = self._buf + lines[0]
self._buf = ""
if not buf.endswith("\n"):
self._buf = lines.pop()
for line in lines:
self._callback(line)
def close(self):
if self._buf:
self._callback(self._buf)
self._buf = ""
def __enter__(self):
return self
def __exit__(self, *args):
self.close()