""" Access and control log capturing. """
from __future__ import absolute_import, division, print_function
import logging
from contextlib import closing, contextmanager
import re
import six
from _pytest.compat import dummy_context_manager
from _pytest.config import create_terminal_writer
import pytest
import py
DEFAULT_LOG_FORMAT = "%(filename)-25s %(lineno)4d %(levelname)-8s %(message)s"
DEFAULT_LOG_DATE_FORMAT = "%H:%M:%S"
class ColoredLevelFormatter(logging.Formatter):
"""
Colorize the %(levelname)..s part of the log format passed to __init__.
"""
LOGLEVEL_COLOROPTS = {
logging.CRITICAL: {"red"},
logging.ERROR: {"red", "bold"},
logging.WARNING: {"yellow"},
logging.WARN: {"yellow"},
logging.INFO: {"green"},
logging.DEBUG: {"purple"},
logging.NOTSET: set(),
}
LEVELNAME_FMT_REGEX = re.compile(r"%\(levelname\)([+-]?\d*s)")
def __init__(self, terminalwriter, *args, **kwargs):
super(ColoredLevelFormatter, self).__init__(*args, **kwargs)
if six.PY2:
self._original_fmt = self._fmt
else:
self._original_fmt = self._style._fmt
self._level_to_fmt_mapping = {}
levelname_fmt_match = self.LEVELNAME_FMT_REGEX.search(self._fmt)
if not levelname_fmt_match:
return
levelname_fmt = levelname_fmt_match.group()
for level, color_opts in self.LOGLEVEL_COLOROPTS.items():
formatted_levelname = levelname_fmt % {
"levelname": logging.getLevelName(level)
}
# add ANSI escape sequences around the formatted levelname
color_kwargs = {name: True for name in color_opts}
colorized_formatted_levelname = terminalwriter.markup(
formatted_levelname, **color_kwargs
)
self._level_to_fmt_mapping[level] = self.LEVELNAME_FMT_REGEX.sub(
colorized_formatted_levelname, self._fmt
)
def format(self, record):
fmt = self._level_to_fmt_mapping.get(record.levelno, self._original_fmt)
if six.PY2:
self._fmt = fmt
else:
self._style._fmt = fmt
return super(ColoredLevelFormatter, self).format(record)
def get_option_ini(config, *names):
for name in names:
ret = config.getoption(name) # 'default' arg won't work as expected
if ret is None:
ret = config.getini(name)
if ret:
return ret
def pytest_addoption(parser):
"""Add options to control log capturing."""
group = parser.getgroup("logging")
def add_option_ini(option, dest, default=None, type=None, **kwargs):
parser.addini(
dest, default=default, type=type, help="default value for " + option
)
group.addoption(option, dest=dest, **kwargs)
add_option_ini(
"--no-print-logs",
dest="log_print",
action="store_const",
const=False,
default=True,
type="bool",
help="disable printing caught logs on failed tests.",
)
add_option_ini(
"--log-level",
dest="log_level",
default=None,
help="logging level used by the logging module",
)
add_option_ini(
"--log-format",
dest="log_format",
default=DEFAULT_LOG_FORMAT,
help="log format as used by the logging module.",
)
add_option_ini(
"--log-date-format",
dest="log_date_format",
default=DEFAULT_LOG_DATE_FORMAT,
help="log date format as used by the logging module.",
)
parser.addini(
"log_cli",
default=False,
type="bool",
help='enable log display during test run (also known as "live logging").',
)
add_option_ini(
"--log-cli-level", dest="log_cli_level", default=None, help="cli logging level."
)
add_option_ini(
"--log-cli-format",
dest="log_cli_format",
default=None,
help="log format as used by the logging module.",
)
add_option_ini(
"--log-cli-date-format",
dest="log_cli_date_format",
default=None,
help="log date format as used by the logging module.",
)
add_option_ini(
"--log-file",
dest="log_file",
default=None,
help="path to a file when logging will be written to.",
)
add_option_ini(
"--log-file-level",
dest="log_file_level",
default=None,
help="log file logging level.",
)
add_option_ini(
"--log-file-format",
dest="log_file_format",
default=DEFAULT_LOG_FORMAT,
help="log format as used by the logging module.",
)
add_option_ini(
"--log-file-date-format",
dest="log_file_date_format",
default=DEFAULT_LOG_DATE_FORMAT,
help="log date format as used by the logging module.",
)
@contextmanager
def catching_logs(handler, formatter=None, level=None):
"""Context manager that prepares the whole logging machinery properly."""
root_logger = logging.getLogger()
if formatter is not None:
handler.setFormatter(formatter)
if level is not None:
handler.setLevel(level)
# Adding the same handler twice would confuse logging system.
# Just don't do that.
add_new_handler = handler not in root_logger.handlers
if add_new_handler:
root_logger.addHandler(handler)
if level is not None:
orig_level = root_logger.level
root_logger.setLevel(min(orig_level, level))
try:
yield handler
finally:
if level is not None:
root_logger.setLevel(orig_level)
if add_new_handler:
root_logger.removeHandler(handler)
class LogCaptureHandler(logging.StreamHandler):
"""A logging handler that stores log records and the log text."""
def __init__(self):
"""Creates a new log handler."""
logging.StreamHandler.__init__(self, py.io.TextIO())
self.records = []
def emit(self, record):
"""Keep the log records in a list in addition to the log text."""
self.records.append(record)
logging.StreamHandler.emit(self, record)
def reset(self):
self.records = []
self.stream = py.io.TextIO()
[docs]class LogCaptureFixture(object):
"""Provides access and control of log capturing."""
def __init__(self, item):
"""Creates a new funcarg."""
self._item = item
self._initial_log_levels = {} # type: Dict[str, int] # dict of log name -> log level
def _finalize(self):
"""Finalizes the fixture.
This restores the log levels changed by :meth:`set_level`.
"""
# restore log levels
for logger_name, level in self._initial_log_levels.items():
logger = logging.getLogger(logger_name)
logger.setLevel(level)
@property
def handler(self):
"""
:rtype: LogCaptureHandler
"""
return self._item.catch_log_handler
[docs] def get_records(self, when):
"""
Get the logging records for one of the possible test phases.
:param str when:
Which test phase to obtain the records from. Valid values are: "setup", "call" and "teardown".
:rtype: List[logging.LogRecord]
:return: the list of captured records at the given stage
.. versionadded:: 3.4
"""
handler = self._item.catch_log_handlers.get(when)
if handler:
return handler.records
else:
return []
@property
def text(self):
"""Returns the log text."""
return self.handler.stream.getvalue()
@property
def records(self):
"""Returns the list of log records."""
return self.handler.records
@property
def record_tuples(self):
"""Returns a list of a striped down version of log records intended
for use in assertion comparison.
The format of the tuple is:
(logger_name, log_level, message)
"""
return [(r.name, r.levelno, r.getMessage()) for r in self.records]
@property
def messages(self):
"""Returns a list of format-interpolated log messages.
Unlike 'records', which contains the format string and parameters for interpolation, log messages in this list
are all interpolated.
Unlike 'text', which contains the output from the handler, log messages in this list are unadorned with
levels, timestamps, etc, making exact comparisions more reliable.
Note that traceback or stack info (from :func:`logging.exception` or the `exc_info` or `stack_info` arguments
to the logging functions) is not included, as this is added by the formatter in the handler.
.. versionadded:: 3.7
"""
return [r.getMessage() for r in self.records]
[docs] def clear(self):
"""Reset the list of log records and the captured log text."""
self.handler.reset()
[docs] def set_level(self, level, logger=None):
"""Sets the level for capturing of logs. The level will be restored to its previous value at the end of
the test.
:param int level: the logger to level.
:param str logger: the logger to update the level. If not given, the root logger level is updated.
.. versionchanged:: 3.4
The levels of the loggers changed by this function will be restored to their initial values at the
end of the test.
"""
logger_name = logger
logger = logging.getLogger(logger_name)
# save the original log-level to restore it during teardown
self._initial_log_levels.setdefault(logger_name, logger.level)
logger.setLevel(level)
[docs] @contextmanager
def at_level(self, level, logger=None):
"""Context manager that sets the level for capturing of logs. After the end of the 'with' statement the
level is restored to its original value.
:param int level: the logger to level.
:param str logger: the logger to update the level. If not given, the root logger level is updated.
"""
logger = logging.getLogger(logger)
orig_level = logger.level
logger.setLevel(level)
try:
yield
finally:
logger.setLevel(orig_level)
[docs]@pytest.fixture
def caplog(request):
"""Access and control log capturing.
Captured logs are available through the following methods::
* caplog.text -> string containing formatted log output
* caplog.records -> list of logging.LogRecord instances
* caplog.record_tuples -> list of (logger_name, level, message) tuples
* caplog.clear() -> clear captured records and formatted log output string
"""
result = LogCaptureFixture(request.node)
yield result
result._finalize()
def get_actual_log_level(config, *setting_names):
"""Return the actual logging level."""
for setting_name in setting_names:
log_level = config.getoption(setting_name)
if log_level is None:
log_level = config.getini(setting_name)
if log_level:
break
else:
return
if isinstance(log_level, six.string_types):
log_level = log_level.upper()
try:
return int(getattr(logging, log_level, log_level))
except ValueError:
# Python logging does not recognise this as a logging level
raise pytest.UsageError(
"'{}' is not recognized as a logging level name for "
"'{}'. Please consider passing the "
"logging level num instead.".format(log_level, setting_name)
)
def pytest_configure(config):
config.pluginmanager.register(LoggingPlugin(config), "logging-plugin")
class LoggingPlugin(object):
"""Attaches to the logging module and captures log messages for each test.
"""
def __init__(self, config):
"""Creates a new plugin to capture log messages.
The formatter can be safely shared across all handlers so
create a single one for the entire test session here.
"""
self._config = config
# enable verbose output automatically if live logging is enabled
if self._log_cli_enabled() and not config.getoption("verbose"):
# sanity check: terminal reporter should not have been loaded at this point
assert self._config.pluginmanager.get_plugin("terminalreporter") is None
config.option.verbose = 1
self.print_logs = get_option_ini(config, "log_print")
self.formatter = logging.Formatter(
get_option_ini(config, "log_format"),
get_option_ini(config, "log_date_format"),
)
self.log_level = get_actual_log_level(config, "log_level")
log_file = get_option_ini(config, "log_file")
if log_file:
self.log_file_level = get_actual_log_level(config, "log_file_level")
log_file_format = get_option_ini(config, "log_file_format", "log_format")
log_file_date_format = get_option_ini(
config, "log_file_date_format", "log_date_format"
)
# Each pytest runtests session will write to a clean logfile
self.log_file_handler = logging.FileHandler(
log_file, mode="w", encoding="UTF-8"
)
log_file_formatter = logging.Formatter(
log_file_format, datefmt=log_file_date_format
)
self.log_file_handler.setFormatter(log_file_formatter)
else:
self.log_file_handler = None
# initialized during pytest_runtestloop
self.log_cli_handler = None
def _log_cli_enabled(self):
"""Return True if log_cli should be considered enabled, either explicitly
or because --log-cli-level was given in the command-line.
"""
return self._config.getoption(
"--log-cli-level"
) is not None or self._config.getini("log_cli")
@contextmanager
def _runtest_for(self, item, when):
"""Implements the internals of pytest_runtest_xxx() hook."""
with catching_logs(
LogCaptureHandler(), formatter=self.formatter, level=self.log_level
) as log_handler:
if self.log_cli_handler:
self.log_cli_handler.set_when(when)
if item is None:
yield # run the test
return
if not hasattr(item, "catch_log_handlers"):
item.catch_log_handlers = {}
item.catch_log_handlers[when] = log_handler
item.catch_log_handler = log_handler
try:
yield # run test
finally:
del item.catch_log_handler
if when == "teardown":
del item.catch_log_handlers
if self.print_logs:
# Add a captured log section to the report.
log = log_handler.stream.getvalue().strip()
item.add_report_section(when, "log", log)
@pytest.hookimpl(hookwrapper=True)
def pytest_runtest_setup(self, item):
with self._runtest_for(item, "setup"):
yield
@pytest.hookimpl(hookwrapper=True)
def pytest_runtest_call(self, item):
with self._runtest_for(item, "call"):
yield
@pytest.hookimpl(hookwrapper=True)
def pytest_runtest_teardown(self, item):
with self._runtest_for(item, "teardown"):
yield
@pytest.hookimpl(hookwrapper=True)
def pytest_runtest_logstart(self):
if self.log_cli_handler:
self.log_cli_handler.reset()
with self._runtest_for(None, "start"):
yield
@pytest.hookimpl(hookwrapper=True)
def pytest_runtest_logfinish(self):
with self._runtest_for(None, "finish"):
yield
@pytest.hookimpl(hookwrapper=True)
def pytest_runtestloop(self, session):
"""Runs all collected test items."""
self._setup_cli_logging()
with self.live_logs_context:
if self.log_file_handler is not None:
with closing(self.log_file_handler):
with catching_logs(
self.log_file_handler, level=self.log_file_level
):
yield # run all the tests
else:
yield # run all the tests
def _setup_cli_logging(self):
"""Sets up the handler and logger for the Live Logs feature, if enabled.
This must be done right before starting the loop so we can access the terminal reporter plugin.
"""
terminal_reporter = self._config.pluginmanager.get_plugin("terminalreporter")
if self._log_cli_enabled() and terminal_reporter is not None:
capture_manager = self._config.pluginmanager.get_plugin("capturemanager")
log_cli_handler = _LiveLoggingStreamHandler(
terminal_reporter, capture_manager
)
log_cli_format = get_option_ini(
self._config, "log_cli_format", "log_format"
)
log_cli_date_format = get_option_ini(
self._config, "log_cli_date_format", "log_date_format"
)
if (
self._config.option.color != "no"
and ColoredLevelFormatter.LEVELNAME_FMT_REGEX.search(log_cli_format)
):
log_cli_formatter = ColoredLevelFormatter(
create_terminal_writer(self._config),
log_cli_format,
datefmt=log_cli_date_format,
)
else:
log_cli_formatter = logging.Formatter(
log_cli_format, datefmt=log_cli_date_format
)
log_cli_level = get_actual_log_level(
self._config, "log_cli_level", "log_level"
)
self.log_cli_handler = log_cli_handler
self.live_logs_context = catching_logs(
log_cli_handler, formatter=log_cli_formatter, level=log_cli_level
)
else:
self.live_logs_context = dummy_context_manager()
class _LiveLoggingStreamHandler(logging.StreamHandler):
"""
Custom StreamHandler used by the live logging feature: it will write a newline before the first log message
in each test.
During live logging we must also explicitly disable stdout/stderr capturing otherwise it will get captured
and won't appear in the terminal.
"""
def __init__(self, terminal_reporter, capture_manager):
"""
:param _pytest.terminal.TerminalReporter terminal_reporter:
:param _pytest.capture.CaptureManager capture_manager:
"""
logging.StreamHandler.__init__(self, stream=terminal_reporter)
self.capture_manager = capture_manager
self.reset()
self.set_when(None)
self._test_outcome_written = False
def reset(self):
"""Reset the handler; should be called before the start of each test"""
self._first_record_emitted = False
def set_when(self, when):
"""Prepares for the given test phase (setup/call/teardown)"""
self._when = when
self._section_name_shown = False
if when == "start":
self._test_outcome_written = False
def emit(self, record):
ctx_manager = (
self.capture_manager.global_and_fixture_disabled()
if self.capture_manager
else dummy_context_manager()
)
with ctx_manager:
if not self._first_record_emitted:
self.stream.write("\n")
self._first_record_emitted = True
elif self._when in ("teardown", "finish"):
if not self._test_outcome_written:
self._test_outcome_written = True
self.stream.write("\n")
if not self._section_name_shown and self._when:
self.stream.section("live log " + self._when, sep="-", bold=True)
self._section_name_shown = True
logging.StreamHandler.emit(self, record)