from copy import deepcopy
import collections
from flask import current_app, request
from werkzeug.datastructures import MultiDict, FileStorage
from werkzeug import exceptions
import flask_restful
import decimal
import six
class Namespace(dict):
def __getattr__(self, name):
try:
return self[name]
except KeyError:
raise AttributeError(name)
def __setattr__(self, name, value):
self[name] = value
_friendly_location = {
u'json': u'the JSON body',
u'form': u'the post body',
u'args': u'the query string',
u'values': u'the post body or the query string',
u'headers': u'the HTTP headers',
u'cookies': u'the request\'s cookies',
u'files': u'an uploaded file',
}
text_type = lambda x: six.text_type(x)
class Argument(object):
"""
:param name: Either a name or a list of option strings, e.g. foo or
-f, --foo.
:param default: The value produced if the argument is absent from the
request.
:param dest: The name of the attribute to be added to the object
returned by :meth:`~reqparse.RequestParser.parse_args()`.
:param bool required: Whether or not the argument may be omitted (optionals
only).
:param action: The basic type of action to be taken when this argument
is encountered in the request. Valid options are "store" and "append".
:param ignore: Whether to ignore cases where the argument fails type
conversion
:param type: The type to which the request argument should be
converted. If a type raises an exception, the message in the
error will be returned in the response. Defaults to :class:`unicode`
in python2 and :class:`str` in python3.
:param location: The attributes of the :class:`flask.Request` object
to source the arguments from (ex: headers, args, etc.), can be an
iterator. The last item listed takes precedence in the result set.
:param choices: A container of the allowable values for the argument.
:param help: A brief description of the argument, returned in the
response when the argument is invalid. May optionally contain
an "{error_msg}" interpolation token, which will be replaced with
the text of the error raised by the type converter.
:param bool case_sensitive: Whether argument values in the request are
case sensitive or not (this will convert all values to lowercase)
:param bool store_missing: Whether the arguments default value should
be stored if the argument is missing from the request.
:param bool trim: If enabled, trims whitespace around the argument.
:param bool nullable: If enabled, allows null value in argument.
"""
def __init__(self, name, default=None, dest=None, required=False,
ignore=False, type=text_type, location=('json', 'values',),
choices=(), action='store', help=None, operators=('=',),
case_sensitive=True, store_missing=True, trim=False,
nullable=True):
self.name = name
self.default = default
self.dest = dest
self.required = required
self.ignore = ignore
self.location = location
self.type = type
self.choices = choices
self.action = action
self.help = help
self.case_sensitive = case_sensitive
self.operators = operators
self.store_missing = store_missing
self.trim = trim
self.nullable = nullable
def __str__(self):
if len(self.choices) > 5:
choices = self.choices[0:3]
choices.append('...')
choices.append(self.choices[-1])
else:
choices = self.choices
return 'Name: {0}, type: {1}, choices: {2}'.format(self.name, self.type, choices)
def __repr__(self):
return "{0}('{1}', default={2}, dest={3}, required={4}, ignore={5}, location={6}, " \
"type=\"{7}\", choices={8}, action='{9}', help={10}, case_sensitive={11}, " \
"operators={12}, store_missing={13}, trim={14}, nullable={15})".format(
self.__class__.__name__, self.name, self.default, self.dest, self.required, self.ignore, self.location,
self.type, self.choices, self.action, self.help, self.case_sensitive,
self.operators, self.store_missing, self.trim, self.nullable)
def source(self, request):
"""Pulls values off the request in the provided location
:param request: The flask request object to parse arguments from
"""
if isinstance(self.location, six.string_types):
value = getattr(request, self.location, MultiDict())
if callable(value):
value = value()
if value is not None:
return value
else:
values = MultiDict()
for l in self.location:
value = getattr(request, l, None)
if callable(value):
value = value()
if value is not None:
values.update(value)
return values
return MultiDict()
def convert(self, value, op):
# Don't cast None
if value is None:
if self.nullable:
return None
else:
raise ValueError('Must not be null!')
# and check if we're expecting a filestorage and haven't overridden `type`
# (required because the below instantiation isn't valid for FileStorage)
elif isinstance(value, FileStorage) and self.type == FileStorage:
return value
try:
return self.type(value, self.name, op)
except TypeError:
try:
if self.type is decimal.Decimal:
return self.type(str(value), self.name)
else:
return self.type(value, self.name)
except TypeError:
return self.type(value)
def handle_validation_error(self, error, bundle_errors):
"""Called when an error is raised while parsing. Aborts the request
with a 400 status and an error message
:param error: the error that was raised
:param bundle_errors: do not abort when first error occurs, return a
dict with the name of the argument and the error message to be
bundled
"""
error_str = six.text_type(error)
error_msg = self.help.format(error_msg=error_str) if self.help else error_str
msg = {self.name: error_msg}
if current_app.config.get("BUNDLE_ERRORS", False) or bundle_errors:
return error, msg
flask_restful.abort(400, message=msg)
def parse(self, request, bundle_errors=False):
"""Parses argument value(s) from the request, converting according to
the argument's type.
:param request: The flask request object to parse arguments from
:param bundle_errors: Do not abort when first error occurs, return a
dict with the name of the argument and the error message to be
bundled
"""
source = self.source(request)
results = []
# Sentinels
_not_found = False
_found = True
for operator in self.operators:
name = self.name + operator.replace("=", "", 1)
if name in source:
# Account for MultiDict and regular dict
if hasattr(source, "getlist"):
values = source.getlist(name)
else:
values = source.get(name)
if not (isinstance(values, collections.MutableSequence) and self.action == 'append'):
values = [values]
for value in values:
if hasattr(value, "strip") and self.trim:
value = value.strip()
if hasattr(value, "lower") and not self.case_sensitive:
value = value.lower()
if hasattr(self.choices, "__iter__"):
self.choices = [choice.lower()
for choice in self.choices]
try:
value = self.convert(value, operator)
except Exception as error:
if self.ignore:
continue
return self.handle_validation_error(error, bundle_errors)
if self.choices and value not in self.choices:
if current_app.config.get("BUNDLE_ERRORS", False) or bundle_errors:
return self.handle_validation_error(
ValueError(u"{0} is not a valid choice".format(
value)), bundle_errors)
self.handle_validation_error(
ValueError(u"{0} is not a valid choice".format(
value)), bundle_errors)
if name in request.unparsed_arguments:
request.unparsed_arguments.pop(name)
results.append(value)
if not results and self.required:
if isinstance(self.location, six.string_types):
error_msg = u"Missing required parameter in {0}".format(
_friendly_location.get(self.location, self.location)
)
else:
friendly_locations = [_friendly_location.get(loc, loc)
for loc in self.location]
error_msg = u"Missing required parameter in {0}".format(
' or '.join(friendly_locations)
)
if current_app.config.get("BUNDLE_ERRORS", False) or bundle_errors:
return self.handle_validation_error(ValueError(error_msg), bundle_errors)
self.handle_validation_error(ValueError(error_msg), bundle_errors)
if not results:
if callable(self.default):
return self.default(), _not_found
else:
return self.default, _not_found
if self.action == 'append':
return results, _found
if self.action == 'store' or len(results) == 1:
return results[0], _found
return results, _found
class RequestParser(object):
"""Enables adding and parsing of multiple arguments in the context of a
single request. Ex::
from flask_restful import reqparse
parser = reqparse.RequestParser()
parser.add_argument('foo')
parser.add_argument('int_bar', type=int)
args = parser.parse_args()
:param bool trim: If enabled, trims whitespace on all arguments in this
parser
:param bool bundle_errors: If enabled, do not abort when first error occurs,
return a dict with the name of the argument and the error message to be
bundled and return all validation errors
"""
def __init__(self, argument_class=Argument, namespace_class=Namespace,
trim=False, bundle_errors=False):
self.args = []
self.argument_class = argument_class
self.namespace_class = namespace_class
self.trim = trim
self.bundle_errors = bundle_errors
def add_argument(self, *args, **kwargs):
"""Adds an argument to be parsed.
Accepts either a single instance of Argument or arguments to be passed
into :class:`Argument`'s constructor.
See :class:`Argument`'s constructor for documentation on the
available options.
"""
if len(args) == 1 and isinstance(args[0], self.argument_class):
self.args.append(args[0])
else:
self.args.append(self.argument_class(*args, **kwargs))
# Do not know what other argument classes are out there
if self.trim and self.argument_class is Argument:
# enable trim for appended element
self.args[-1].trim = kwargs.get('trim', self.trim)
return self
def parse_args(self, req=None, strict=False, http_error_code=400):
"""Parse all arguments from the provided request and return the results
as a Namespace
:param req: Can be used to overwrite request from Flask
:param strict: if req includes args not in parser, throw 400 BadRequest exception
:param http_error_code: use custom error code for `flask_restful.abort()`
"""
if req is None:
req = request
namespace = self.namespace_class()
# A record of arguments not yet parsed; as each is found
# among self.args, it will be popped out
req.unparsed_arguments = dict(self.argument_class('').source(req)) if strict else {}
errors = {}
for arg in self.args:
value, found = arg.parse(req, self.bundle_errors)
if isinstance(value, ValueError):
errors.update(found)
found = None
if found or arg.store_missing:
namespace[arg.dest or arg.name] = value
if errors:
flask_restful.abort(http_error_code, message=errors)
if strict and req.unparsed_arguments:
raise exceptions.BadRequest('Unknown arguments: %s'
% ', '.join(req.unparsed_arguments.keys()))
return namespace
def copy(self):
""" Creates a copy of this RequestParser with the same set of arguments """
parser_copy = self.__class__(self.argument_class, self.namespace_class)
parser_copy.args = deepcopy(self.args)
parser_copy.trim = self.trim
parser_copy.bundle_errors = self.bundle_errors
return parser_copy
def replace_argument(self, name, *args, **kwargs):
""" Replace the argument matching the given name with a new version. """
new_arg = self.argument_class(name, *args, **kwargs)
for index, arg in enumerate(self.args[:]):
if new_arg.name == arg.name:
del self.args[index]
self.args.append(new_arg)
break
return self
def remove_argument(self, name):
""" Remove the argument matching the given name. """
for index, arg in enumerate(self.args[:]):
if name == arg.name:
del self.args[index]
break
return self