def __init__(self, node_name: valid_node_name, cage_name: valid_cage_name,
cage_directory: os_path.isdir, log: callable, log_priority: int):
self._node_name, self._cage_name = node_name, cage_name
self._log, self._log_priority = log, log_priority
self._cage_directory = cage_directory
self._module_locator = ModuleLocator(self._cage_directory)
self._lock, self._modules, self._loggers = Lock(), {}, {}
class ModuleLoader:
@typecheck
def __init__(self, node_name: valid_node_name, cage_name: valid_cage_name,
cage_directory: os_path.isdir, log: callable, log_priority: int):
self._node_name, self._cage_name = node_name, cage_name
self._log, self._log_priority = log, log_priority
self._cage_directory = cage_directory
self._module_locator = ModuleLocator(self._cage_directory)
self._lock, self._modules, self._loggers = Lock(), {}, {}
###################################
class _Logger:
def __init__(self, log, log_priority, src_module):
self._log, self._log_priority = log, log_priority
self._src_module = src_module
def __call__(self, s, priority = None):
try:
if priority is None:
return self(s, priority = 4)
elif priority <= self._log_priority:
while not isinstance(s, str):
try:
s = str(s)
except:
s = str(s.__class__)
request = getattr(current_thread(), "_request", None)
req_desc = request.description if request else ""
req_desc = " by {0:s}".format(req_desc) if req_desc else ""
if self._src_module:
line, func = extract_stack(None, 3)[-3][1:3]
s += " # {0:s}.py:{1:d} in {2:s}(){3:s}".\
format(self._src_module, line, func, req_desc)
elif req_desc:
s += " #{0:s}".format(req_desc)
self._log(s, priority = priority)
except:
pass # do nothing
error = lambda self, s: self(s, priority = 1)
message = lambda self, s: self(s, priority = 2)
warning = lambda self, s: self(s, priority = 3)
info = lambda self, s: self(s, priority = 5)
debug = lambda self, s: self(s, priority = 6)
def set_log_priority(self, log_priority):
with self._lock:
if self._log_priority != log_priority:
self._log_priority = log_priority
self._loggers.clear()
###################################
def __getattr__(self, module_name, src_module = None):
# special case #1: pmnc.log[.error|.message|.warning|.info|.debug](s)
# I prefer to cache logger instances created for each module for two
# reasons: (1) runtime exception safety and (2) performance
if module_name == "log":
with self._lock:
logger = self._loggers.get(src_module)
if logger is None:
logger = ModuleLoader._Logger(self._log, self._log_priority, src_module)
self._loggers[src_module] = logger
return logger
# special case #2: pmnc.request
request = current_thread()._request
if module_name == "request":
return request
# reserve a private namespace for modules
if module_name.startswith("_"):
raise InvalidModuleNameError("module name cannot start with underscore")
# locate the file containing the required module
module_filename = \
self._module_locator.locate("{0:s}.py".format(module_name)) or \
self._module_locator.locate("{0:s}.pyc".format(module_name))
if module_filename is None:
raise ModuleNotFoundError("file {0:s}.py was not found".format(module_name))
# see if such module has already been loaded, create an empty object if it hasn't
with self._lock:
module = self._modules.get(module_name)
if not module:
module = Module(module_name, self)
self._modules[module_name] = module
# reload the module if necessary and return the proxy object
return module.reload(module_filename, request, src_module)
