Merge pull request #706 from ZyX-I/better-errors

Better error handling
This commit is contained in:
ZyX-I 2014-01-26 10:43:16 -08:00
commit a4e8f36f36
4 changed files with 96 additions and 12 deletions

View File

@ -10,10 +10,43 @@ from powerline.lib.config import ConfigLoader
from threading import Lock, Event
try:
from __builtin__ import unicode
except ImportError:
unicode = str # NOQA
DEFAULT_SYSTEM_CONFIG_DIR = None
def safe_unicode(s):
'''Return unicode instance without raising an exception.
'''
try:
try:
return unicode(s)
except UnicodeDecodeError:
try:
return unicode(s, 'utf-8')
except TypeError:
return unicode(str(s), 'utf-8')
except Exception as e:
return safe_unicode(e)
class FailedUnicode(unicode):
'''Builtin ``unicode`` (``str`` in python 3) subclass indicating fatal
error.
If your code for some reason wants to determine whether `.render()` method
failed it should check returned string for being a FailedUnicode instance.
Alternatively you could subclass Powerline and override `.render()` method
to do what you like in place of catching the exception and returning
FailedUnicode.
'''
pass
def find_config_file(search_paths, config_file):
config_file += '.json'
for path in search_paths:
@ -61,6 +94,29 @@ class PowerlineLogger(object):
self._log('debug', msg, *args, **kwargs)
_fallback_logger = None
def _get_fallback_logger():
global _fallback_logger
if _fallback_logger:
return _fallback_logger
log_format = '%(asctime)s:%(levelname)s:%(message)s'
formatter = logging.Formatter(log_format)
level = logging.WARNING
handler = logging.StreamHandler()
handler.setLevel(level)
handler.setFormatter(formatter)
logger = logging.getLogger('powerline')
logger.setLevel(level)
logger.addHandler(handler)
_fallback_logger = PowerlineLogger(None, logger, '_fallback_')
return _fallback_logger
class Powerline(object):
'''Main powerline class, entrance point for all powerline uses. Sets
powerline up and loads the configuration.
@ -233,7 +289,7 @@ class Powerline(object):
try:
Renderer = __import__(self.renderer_module, fromlist=['renderer']).renderer
except Exception as e:
self.pl.exception('Failed to import renderer module: {0}', str(e))
self.exception('Failed to import renderer module: {0}', str(e))
sys.exit(1)
# Renderer updates configuration file via segments .startup thus it
@ -242,7 +298,7 @@ class Powerline(object):
try:
renderer = Renderer(**self.renderer_options)
except Exception as e:
self.pl.exception('Failed to construct renderer object: {0}', str(e))
self.exception('Failed to construct renderer object: {0}', str(e))
if not hasattr(self, 'renderer'):
raise
else:
@ -360,16 +416,34 @@ class Powerline(object):
try:
self.create_renderer(**create_renderer_kwargs)
except Exception as e:
self.pl.exception('Failed to create renderer: {0}', str(e))
finally:
self.create_renderer_kwargs.clear()
self.exception('Failed to create renderer: {0}', str(e))
if hasattr(self, 'renderer'):
with self.cr_kwargs_lock:
self.create_renderer_kwargs.clear()
else:
raise
else:
with self.cr_kwargs_lock:
self.create_renderer_kwargs.clear()
def render(self, *args, **kwargs):
'''Update/create renderer if needed and pass all arguments further to
``self.renderer.render()``.
'''
self.update_renderer()
return self.renderer.render(*args, **kwargs)
try:
self.update_renderer()
return self.renderer.render(*args, **kwargs)
except Exception as e:
try:
self.exception('Failed to render: {0}', str(e))
except Exception as e:
# Updates e variable to new value, masking previous one.
# Normally it is the same exception (due to raise in case pl is
# unset), but it may also show error in logger. Note that latter
# is not logged by logger for obvious reasons, thus this also
# prevents us from seeing logger traceback.
pass
return FailedUnicode(safe_unicode(e))
def shutdown(self):
'''Shut down all background threads. Must be run only prior to exiting
@ -410,3 +484,9 @@ class Powerline(object):
def __exit__(self, *args):
self.shutdown()
def exception(self, msg, *args, **kwargs):
if 'prefix' not in kwargs:
kwargs['prefix'] = 'powerline'
pl = getattr(self, 'pl', None) or _get_fallback_logger()
return pl.exception(msg, *args, **kwargs)

View File

@ -155,6 +155,10 @@ class ConfigLoader(MultiRunnedThread):
try:
self.loaded[path] = deepcopy(self._load(path))
except Exception as e:
try:
self.loaded.pop(path)
except KeyError:
pass
self.exception('Error while loading {0}: {1}', path, str(e))
def run(self):

View File

@ -707,13 +707,13 @@ class NetworkLoadSegment(KwThreadedSegment):
total = activity
interface = name
if interface in self.interfaces:
try:
idata = self.interfaces[interface]
try:
idata['prev'] = idata['last']
except KeyError:
pass
else:
except KeyError:
idata = {}
if self.run_once:
idata['prev'] = (monotonic(), _get_bytes(interface))

View File

@ -141,7 +141,7 @@ class TestConfigReload(TestCase):
self.assertEqual(p.render(), '<1 2 1> s <2 4 False>>><3 4 4>g <4 False False>>><None None None>')
self.assertAccessEvents('config', 'themes/test/nonexistent')
# It should normally handle file missing error
self.assertEqual(p.logger._pop_msgs(), ['exception:test:Failed to create renderer: themes/test/nonexistent'])
self.assertEqual(p.logger._pop_msgs(), ['exception:test:powerline:Failed to create renderer: themes/test/nonexistent'])
config['config']['ext']['test']['theme'] = 'default'
add_watcher_events(p, 'config')
@ -154,7 +154,7 @@ class TestConfigReload(TestCase):
self.assertEqual(p.render(), '<1 2 1> s <2 4 False>>><3 4 4>g <4 False False>>><None None None>')
self.assertAccessEvents('config', 'colorschemes/test/nonexistent')
# It should normally handle file missing error
self.assertEqual(p.logger._pop_msgs(), ['exception:test:Failed to create renderer: colorschemes/test/nonexistent'])
self.assertEqual(p.logger._pop_msgs(), ['exception:test:powerline:Failed to create renderer: colorschemes/test/nonexistent'])
config['config']['ext']['test']['colorscheme'] = '2'
add_watcher_events(p, 'config')
@ -187,7 +187,7 @@ class TestConfigReload(TestCase):
add_watcher_events(p, 'config')
self.assertEqual(p.render(), '<1 2 1> s<2 4 False>>><3 4 4>g<4 False False>>><None None None>')
self.assertAccessEvents('config')
self.assertIn('exception:test:Failed to create renderer: fcf:colorschemes/test/nonexistentraise', p.logger._pop_msgs())
self.assertIn('exception:test:powerline:Failed to create renderer: fcf:colorschemes/test/nonexistentraise', p.logger._pop_msgs())
config['colorschemes/test/nonexistentraise'] = {
'groups': {