def decorator_interceptor(*args, **kwargs):
"""
The interceptor function for the transaction decorator.
"""
# retrieves the self reference
self = args[0]
# retrieves the request reference and uses it to retrieve
# the associated parameters instance to be used in the
# operations to be done in the decorator
request = args[1]
parameters = request.parameters
try:
# calls the callback function,
# retrieving the return value
return_value = colony.call_safe(function, *args, **kwargs)
except BaseException as exception:
# logs a warning message because if an exception reached
# this area it must be considered not handled gracefully
# and must be considered an anomaly
self.warning(
"There was an exception in controller (%s): " %\
exception.__class__.__name__ + colony.legacy.UNICODE(exception)
)
# retrieves the serializer and the exception
# values from the parameters
serializer = parameters.get("serializer", None)
exception_handler = parameters.get("exception_handler", None)
# in case the serializer and the exception
# handler are not set must raise the exception
# to the top levels, nothing to be done here
if not serializer and not exception_handler: raise
# verifies if the current exception contains a status
# code attribute and in case it does uses it instead
# of the default (fallback) error status code
has_status_code = hasattr(exception, "status_code")
status_code = exception.status_code if\
has_status_code else ERROR_STATUS_CODE
# sets the error status code in the current request indicating
# that a problem has occurred (default behavior)
self.set_status_code(request, status_code)
# retrieves the exception map for the exception, this map should
# include extra information on the request together with the "base"
# information about the exception to be handled
exception_map = self.get_exception_map(exception, request)
# retrieves the exception value from the exception map and then
# unpacks it into its components of message or traceback
exception = exception_map.get("exception")
message = exception.get("message")
traceback = exception.get("traceback")
# in case the serializer is set (uses it as it
# is has priority)
if serializer:
# dumps the exception map to the serialized form ant then
# sets the serialized map as the request contents with
# the appropriate mime type
exception_map_serialized = serializer.dumps(exception_map)
mime_type = serializer.get_mime_type()
self.set_contents(
request,
exception_map_serialized,
content_type = mime_type
)
# sets the return value as invalid (error)
return_value = False
# in case the exception handler is set, must call the proper action
# method so that the visual exception handler is called
elif exception_handler:
# retrieves the proper name for the exception handler action method
# taking into account the "complex" naming scheme and the simplified
# one os that it maintain compatibility with both schemes, then calls
# the action method (handler) with the exception map as argument
has_simple = hasattr(exception_handler, "exception")
method_name = "exception" if has_simple else "handle_exception"
method = getattr(exception_handler, method_name)
return_value = colony.call_safe(
method,
request,
parameters = exception_map,
message = message,
traceback = traceback
)
else:
# checks if the current message is already flushed (data sent to
# the output) and in case it's not and there should be a default
# success message sent the default success message is create, then
# serialized and written to the output stream in the request
is_flushed = request.is_flushed()
serializer = parameters.get("serializer", None)
should_default = not is_flushed and default_success and serializer
if should_default:
success_serialized = serializer.dumps(dict(result = "success"))
mime_type = serializer.get_mime_type()
self.set_contents(
request,
success_serialized,
content_type = mime_type
)
# returns the return value, resulting from the decorated method
# this should be an already serialized value
return return_value
def decorator_interceptor(*args, **kwargs):
"""
The interceptor function for the transaction decorator.
"""
# retrieves the self reference
self = args[0]
# retrieves the request reference and uses it to retrieve
# the associated parameters instance to be used in the
# operations to be done in the decorator
request = args[1]
parameters = request.parameters
# retrieves the value for the serializer attribute, if this
# value is defined it must contain a callable object that is
# able to serialize any dictionary oriented value
seralizer = parameters.get("serializer", None)
# in case the call validation flag is not defined the value
# of the should call (validation) flag must be inferred from
# the existence or not of the serializer, because serialized
# methods are not considered to be validated
if call_validation_failed == None:
should_call = False if seralizer else True
# otherwise simply use the call validation failed value as the
# value for the should call boolean flag (transition of value)
else: should_call = call_validation_failed
# in case the controller instance does not have the validate method
# an exception should be raised indicating the problem
if not hasattr(self, "validate"):
raise exceptions.ControllerValidationError("validation method not found", self)
# tests if the controller instance contains the validate method and
# then tries to retrieve the current state of validation for the request
# workflow, if the current request is already validated or if the current
# controller does not contain a validate method the validation should
# not be ran
contains_validate = hasattr(self, "validate")
validated = parameters.get("validated", False)
run_validate = contains_validate and not validated
# calls the validate method with the request
# the parameters and the validation parameters and retrieves
# the list with the validation failure reasons, in case no validate
# method is present ignores the call
reasons_list = run_validate and\
self.validate(request, parameters, validation_parameters) or []
# updates the validated flag for the current request workflow so that
# no second validation occurs, this is the default (top to down) expected
# behavior as only the front-end method gets validated
parameters["validated"] = True
# tries to retrieves the validation failed method from the current controller
# instance, this is going to be used in case the validation method is enabled
validation_failed_method = hasattr(self, "validation_failed") and\
self.validation_failed or None
# in case the reasons list is not empty, there was a validation that failed
# and so either the validation failed method must be called or an exception
# should be immediately raised indicating the problem
if reasons_list:
# in case a validation failed method is defined and
# the validation method should be called (by flag)
if validation_failed_method and should_call:
# calls the validation failed method with the request the parameters the
# validation parameters and the reasons list and sets the return value
return_value = validation_failed_method(
request,
parameters,
validation_parameters,
reasons_list
)
# otherwise there is no validation method defined and the exception
# must be raised (default fallback strategy)
else:
# raises the controller validation failed exception to indicate that
# there was a problem validating the controller's action method
raise exceptions.ControllerValidationReasonFailed(
"validation failed for a series of reasons: " + str(reasons_list),
self,
reasons_list
)
# otherwise the reason list is empty (no errors have occurred) and so the
# "normal" function call workflow must be used
else: return_value = colony.call_safe(function, *args, **kwargs)
# returns the return value, retrieved from either the
# validation method or form the decorated function
return return_value
