# coding=utf-8 import datetime import decimal import functools import time import itertools import pprint import re import translationstring import warnings import types from .compat import ( text_, text_type, string_types, xrange, is_nonstr_iter, ) from . import iso8601 _ = translationstring.TranslationStringFactory('colander') class _required(object): """ Represents a required value in colander-related operations. """ def __repr__(self): return '' required = _required() _marker = required # bw compat class _null(object): """ Represents a null value in colander-related operations. """ def __nonzero__(self): return False # py3 compat __bool__ = __nonzero__ def __repr__(self): return '' def __reduce__(self): return 'null' # when unpickled, refers to "null" below (singleton) null = _null() class _drop(object): """ Represents a value that will be dropped from the schema if it is missing during *serialization* or *deserialization*. Passed as a value to the `missing` or `default` keyword argument of :class:`SchemaNode`. """ def __repr__(self): return '' drop = _drop() def interpolate(msgs): for s in msgs: if hasattr(s, 'interpolate'): yield s.interpolate() else: yield s class UnboundDeferredError(Exception): """ An exception raised by :meth:`SchemaNode.deserialize` when an attempt is made to deserialize a node which has an unbound :class:`deferred` validator. """ class Invalid(Exception): """ An exception raised by data types and validators indicating that the value for a particular node was not valid. The constructor receives a mandatory ``node`` argument. This must be an instance of the :class:`colander.SchemaNode` class, or at least something with the same interface. The constructor also receives an optional ``msg`` keyword argument, defaulting to ``None``. The ``msg`` argument is a freeform field indicating the error circumstance. The constructor additionally may receive an optional ``value`` keyword, indicating the value related to the error. """ pos = None positional = False def __init__(self, node, msg=None, value=None): Exception.__init__(self, node, msg) self.node = node self.msg = msg self.value = value self.children = [] def messages(self): """ Return an iterable of error messages for this exception using the ``msg`` attribute of this error node. If the ``msg`` attribute is iterable, it is returned. If it is not iterable, and is non-``None``, a single-element list containing the ``msg`` value is returned. If the value is ``None``, an empty list is returned.""" if is_nonstr_iter(self.msg): return self.msg if self.msg is None: return [] return [self.msg] def add(self, exc, pos=None): """ Add a child exception; ``exc`` must be an instance of :class:`colander.Invalid` or a subclass. ``pos`` is a value important for accurate error reporting. If it is provided, it must be an integer representing the position of ``exc`` relative to all other subexceptions of this exception node. For example, if the exception being added is about the third child of the exception which is ``self``, ``pos`` might be passed as ``3``. If ``pos`` is provided, it will be assigned to the ``pos`` attribute of the provided ``exc`` object. """ if self.node and isinstance(self.node.typ, Positional): exc.positional = True if pos is not None: exc.pos = pos self.children.append(exc) def __setitem__(self, name, msg): """ Add a subexception related to a child node with the message ``msg``. ``name`` must be present in the names of the set of child nodes of this exception's node; if this is not so, a :exc:`KeyError` is raised. For example, if the exception upon which ``__setitem__`` is called has a node attribute, and that node attribute has children that have the names ``name`` and ``title``, you may successfully call ``__setitem__('name', 'Bad name')`` or ``__setitem__('title', 'Bad title')``. But calling ``__setitem__('wrong', 'whoops')`` will result in a :exc:`KeyError`. This method is typically only useful if the ``node`` attribute of the exception upon which it is called is a schema node representing a mapping. """ for num, child in enumerate(self.node.children): if child.name == name: exc = Invalid(child, msg) self.add(exc, num) return raise KeyError(name) def paths(self): """ A generator which returns each path through the exception graph. Each path is represented as a tuple of exception nodes. Within each tuple, the leftmost item will represent the root schema node, the rightmost item will represent the leaf schema node.""" def traverse(node, stack): stack.append(node) if not node.children: yield tuple(stack) for child in node.children: for path in traverse(child, stack): yield path stack.pop() return traverse(self, []) def _keyname(self): if self.positional: return str(self.pos) return str(self.node.name) def asdict(self, translate=None, separator='; '): """ Return a dictionary containing a basic (non-language-translated) error report for this exception. If ``translate`` is supplied, it must be a callable taking a translation string as its sole argument and returning a localized, interpolated string. If ``separator`` is supplied, error messages are joined with that. """ paths = self.paths() errors = {} for path in paths: keyparts = [] msgs = [] for exc in path: exc.msg and msgs.extend(exc.messages()) keyname = exc._keyname() keyname and keyparts.append(keyname) if translate: msgs = [translate(msg) for msg in msgs] msgs = interpolate(msgs) if separator: msgs = separator.join(msgs) else: msgs = list(msgs) errors['.'.join(keyparts)] = msgs return errors def __str__(self): """ Return a pretty-formatted string representation of the result of an execution of this exception's ``asdict`` method""" return pprint.pformat(self.asdict()) class UnsupportedFields(Invalid): """ Exception used when schema object detect unknown fields in the cstruct during deserialize. """ def __init__(self, node, fields, msg=None): super(UnsupportedFields, self).__init__(node, msg) self.fields = fields class All(object): """ Composite validator which succeeds if none of its subvalidators raises an :class:`colander.Invalid` exception""" def __init__(self, *validators): self.validators = validators def __call__(self, node, value): excs = [] for validator in self.validators: try: validator(node, value) except Invalid as e: excs.append(e) if excs: exc = Invalid(node, [exc.msg for exc in excs]) for e in excs: exc.children.extend(e.children) raise exc class Any(All): """ Composite validator which succeeds if at least one of its subvalidators does not raise an :class:`colander.Invalid` exception.""" def __call__(self, node, value): try: return super(Any, self).__call__(node, value) except Invalid as e: if len(e.msg) < len(self.validators): # At least one validator did not fail: return raise class Function(object): """ Validator which accepts a function and an optional message; the function is called with the ``value`` during validation. If the function returns anything falsy (``None``, ``False``, the empty string, ``0``, an object with a ``__nonzero__`` that returns ``False``, etc) when called during validation, an :exc:`colander.Invalid` exception is raised (validation fails); its msg will be the value of the ``msg`` argument passed to this class' constructor. If the function returns a stringlike object (a ``str`` or ``unicode`` object) that is *not* the empty string , a :exc:`colander.Invalid` exception is raised using the stringlike value returned from the function as the exeption message (validation fails). If the function returns anything *except* a stringlike object object which is truthy (e.g. ``True``, the integer ``1``, an object with a ``__nonzero__`` that returns ``True``, etc), an :exc:`colander.Invalid` exception is *not* raised (validation succeeds). The default value for the ``msg`` when not provided via the constructor is ``Invalid value``. The ``message`` parameter has been deprecated, use ``msg`` instead. """ def __init__(self, function, msg=None, message=None): self.function = function if msg is not None and message is not None: raise ValueError('Only one of msg and message can be passed') # Handle bw compat if msg is None and message is None: msg = _('Invalid value') elif message is not None: warnings.warn( 'The "message" argument has been deprecated, use "msg" ' 'instead.', DeprecationWarning ) msg = message self.msg = msg def __call__(self, node, value): result = self.function(value) if not result: raise Invalid( node, translationstring.TranslationString( self.msg, mapping={'val':value})) if isinstance(result, string_types): raise Invalid( node, translationstring.TranslationString( result, mapping={'val':value})) class Regex(object): """ Regular expression validator. Initialize it with the string regular expression ``regex`` that will be compiled and matched against ``value`` when validator is called. It uses Python's :py:func:`re.match`, which only matches at the beginning of the string and not at the beginning of each line. To match the entire string, enclose the regular expression with ``^`` and ``$``. If ``msg`` is supplied, it will be the error message to be used; otherwise, defaults to 'String does not match expected pattern'. The ``regex`` expression behaviour can be modified by specifying any ``flags`` value taken by ``re.compile``. The ``regex`` argument may also be a pattern object (the result of ``re.compile``) instead of a string. When calling, if ``value`` matches the regular expression, validation succeeds; otherwise, :exc:`colander.Invalid` is raised with the ``msg`` error message. """ def __init__(self, regex, msg=None, flags=0): if isinstance(regex, string_types): self.match_object = re.compile(regex, flags) else: self.match_object = regex if msg is None: self.msg = _("String does not match expected pattern") else: self.msg = msg def __call__(self, node, value): if self.match_object.match(value) is None: raise Invalid(node, self.msg) EMAIL_RE = "(?i)^[A-Z0-9._%!#$%&'*+-/=?^_`{|}~()]+@[A-Z0-9]+([.-][A-Z0-9]+)*\.[A-Z]{2,22}$" class Email(Regex): """ Email address validator. If ``msg`` is supplied, it will be the error message to be used when raising :exc:`colander.Invalid`; otherwise, defaults to 'Invalid email address'. """ def __init__(self, msg=None): email_regex = text_(EMAIL_RE) if msg is None: msg = _("Invalid email address") super(Email, self).__init__(email_regex, msg=msg) class Range(object): """ Validator which succeeds if the value it is passed is greater or equal to ``min`` and less than or equal to ``max``. If ``min`` is not specified, or is specified as ``None``, no lower bound exists. If ``max`` is not specified, or is specified as ``None``, no upper bound exists. ``min_err`` is used to form the ``msg`` of the :exc:`colander.Invalid` error when reporting a validation failure caused by a value not meeting the minimum. If ``min_err`` is specified, it must be a string. The string may contain the replacement targets ``${min}`` and ``${val}``, representing the minimum value and the provided value respectively. If it is not provided, it defaults to ``'${val} is less than minimum value ${min}'``. ``max_err`` is used to form the ``msg`` of the :exc:`colander.Invalid` error when reporting a validation failure caused by a value exceeding the maximum. If ``max_err`` is specified, it must be a string. The string may contain the replacement targets ``${max}`` and ``${val}``, representing the maximum value and the provided value respectively. If it is not provided, it defaults to ``'${val} is greater than maximum value ${max}'``. """ _MIN_ERR = _('${val} is less than minimum value ${min}') _MAX_ERR = _('${val} is greater than maximum value ${max}') def __init__(self, min=None, max=None, min_err=_MIN_ERR, max_err=_MAX_ERR): self.min = min self.max = max self.min_err = min_err self.max_err = max_err def __call__(self, node, value): if self.min is not None: if value < self.min: min_err = _( self.min_err, mapping={'val':value, 'min':self.min}) raise Invalid(node, min_err) if self.max is not None: if value > self.max: max_err = _( self.max_err, mapping={'val':value, 'max':self.max}) raise Invalid(node, max_err) class Length(object): """Validator which succeeds if the value passed to it has a length between a minimum and maximum, expressed in the optional ``min`` and ``max`` arguments. The value can be any sequence, most often a string. If ``min`` is not specified, or is specified as ``None``, no lower bound exists. If ``max`` is not specified, or is specified as ``None``, no upper bound exists. The default error messages are "Shorter than minimum length ${min}" and "Longer than maximum length ${max}". These can be customized: ``min_err`` is used to form the ``msg`` of the :exc:`colander.Invalid` error when reporting a validation failure caused by a value not meeting the minimum length. If ``min_err`` is specified, it must be a string. The string may contain the replacement target ``${min}``. ``max_err`` is used to form the ``msg`` of the :exc:`colander.Invalid` error when reporting a validation failure caused by a value exceeding the maximum length. If ``max_err`` is specified, it must be a string. The string may contain the replacement target ``${max}``. """ _MIN_ERR = _('Shorter than minimum length ${min}') _MAX_ERR = _('Longer than maximum length ${max}') def __init__(self, min=None, max=None, min_err=_MIN_ERR, max_err=_MAX_ERR): self.min = min self.max = max self.min_err = min_err self.max_err = max_err def __call__(self, node, value): if self.min is not None: if len(value) < self.min: min_err = _(self.min_err, mapping={'min': self.min}) raise Invalid(node, min_err) if self.max is not None: if len(value) > self.max: max_err = _(self.max_err, mapping={'max': self.max}) raise Invalid(node, max_err) class OneOf(object): """ Validator which succeeds if the value passed to it is one of a fixed set of values """ def __init__(self, choices): self.choices = choices def __call__(self, node, value): if not value in self.choices: choices = ', '.join(['%s' % x for x in self.choices]) err = _('"${val}" is not one of ${choices}', mapping={'val':value, 'choices':choices}) raise Invalid(node, err) class NoneOf(object): """ Validator which succeeds if the value passed to it is none of a fixed set of values. ``msg_err`` is used to form the ``msg`` of the :exc:`colander.Invalid` error when reporting a validation failure. If ``msg_err`` is specified, it must be a string. The string may contain the replacement targets ``${choices}`` and ``${val}``, representing the set of forbidden values and the provided value respectively. """ _MSG_ERR = _('"${val}" must not be one of ${choices}') def __init__(self, choices, msg_err=_MSG_ERR): self.forbidden = choices self.msg_err = msg_err def __call__(self, node, value): if value not in self.forbidden: return choices = ', '.join(['%s' % x for x in self.forbidden]) err = _(self.msg_err, mapping={'val': value, 'choices': choices}) raise Invalid(node, err) class ContainsOnly(object): """ Validator which succeeds if the value passed to is a sequence and each element in the sequence is also in the sequence passed as ``choices``. This validator is useful when attached to a schemanode with, e.g. a :class:`colander.Set` or another sequencetype. """ err_template = _( 'One or more of the choices you made was not acceptable' ) def __init__(self, choices): self.choices = choices def __call__(self, node, value): if not set(value).issubset(self.choices): err = _( self.err_template, mapping = {'val':value, 'choices':self.choices} ) raise Invalid(node, err) def luhnok(node, value): """ Validator which checks to make sure that the value passes a luhn mod-10 checksum (credit cards). ``value`` must be a string, not an integer.""" try: sum = _luhnok(value) except: raise Invalid(node, _('"${val}" is not a valid credit card number', mapping={'val': value})) if not (sum % 10) == 0: raise Invalid(node, _('"${val}" is not a valid credit card number', mapping={'val': value})) def _luhnok(value): sum = 0 num_digits = len(value) oddeven = num_digits & 1 for count in range(0, num_digits): digit = int(value[count]) if not (( count & 1 ) ^ oddeven ): digit = digit * 2 if digit > 9: digit = digit - 9 sum = sum + digit return sum URL_REGEX = r"""(?i)\b((?:[a-z][\w-]+:(?:/{1,3}|[a-z0-9%])|www\d{0,3}[.]|[a-z0-9.\-]+[.][a-z]{2,4}/)(?:[^\s()<>]+|\(([^\s()<>]+|(\([^\s()<>]+\)))*\))+(?:\(([^\s()<>]+|(\([^\s()<>]+\)))*\)|[^\s`!()\[\]{};:'".,<>?«»“”‘’]))""" # "emacs! url = Regex(URL_REGEX, _('Must be a URL')) UUID_REGEX = r"""^(?:urn:uuid:)?\{?[a-f0-9]{8}(?:-?[a-f0-9]{4}){3}-?[a-f0-9]{12}\}?$""" uuid = Regex(UUID_REGEX, _('Invalid UUID string'), re.IGNORECASE) class SchemaType(object): """ Base class for all schema types """ def flatten(self, node, appstruct, prefix='', listitem=False): result = {} if listitem: selfname = prefix else: selfname = '%s%s' % (prefix, node.name) result[selfname.rstrip('.')] = appstruct return result def unflatten(self, node, paths, fstruct): name = node.name assert paths == [name], "paths should be [name] for leaf nodes." return fstruct[name] def set_value(self, node, appstruct, path, value): raise AssertionError("Can't call 'set_value' on a leaf node.") def get_value(self, node, appstruct, path): raise AssertionError("Can't call 'get_value' on a leaf node.") def cstruct_children(self, node, cstruct): return [] class Mapping(SchemaType): """ A type which represents a mapping of names to nodes. The subnodes of the :class:`colander.SchemaNode` that wraps this type imply the named keys and values in the mapping. The constructor of this type accepts one extra optional keyword argument that other types do not: ``unknown``. An attribute of the same name can be set on a type instance to control the behavior after construction. unknown ``unknown`` controls the behavior of this type when an unknown key is encountered in the cstruct passed to the ``deserialize`` method of this instance. All the potential values of ``unknown`` are strings. They are: - ``ignore`` means that keys that are not present in the schema associated with this type will be ignored during deserialization. - ``raise`` will cause a :exc:`colander.Invalid` exception to be raised when unknown keys are present in the cstruct during deserialization. - ``preserve`` will preserve the 'raw' unknown keys and values in the appstruct returned by deserialization. Default: ``ignore``. Special behavior is exhibited when a subvalue of a mapping is present in the schema but is missing from the mapping passed to either the ``serialize`` or ``deserialize`` method of this class. In this case, the :attr:`colander.null` value will be passed to the ``serialize`` or ``deserialize`` method of the schema node representing the subvalue of the mapping respectively. During serialization, this will result in the behavior described in :ref:`serializing_null` for the subnode. During deserialization, this will result in the behavior described in :ref:`deserializing_null` for the subnode. If the :attr:`colander.null` value is passed to the serialize method of this class, a dictionary will be returned, where each of the values in the returned dictionary is the serialized representation of the null value for its type. """ def __init__(self, unknown='ignore'): self.unknown = unknown def _set_unknown(self, value): if not value in ('ignore', 'raise', 'preserve'): raise ValueError( 'unknown attribute must be one of "ignore", "raise", ' 'or "preserve"') self._unknown = value def _get_unknown(self): return self._unknown unknown = property(_get_unknown, _set_unknown) def _validate(self, node, value): try: if hasattr(value, 'items'): return dict(value) else: raise TypeError('Does not implement dict-like functionality.') except Exception as e: raise Invalid(node, _('"${val}" is not a mapping type: ${err}', mapping = {'val':value, 'err':e}) ) def cstruct_children(self, node, cstruct): if cstruct is null: value = {} else: value = self._validate(node, cstruct) children = [] for subnode in node.children: name = subnode.name subval = value.get(name, _marker) if subval is _marker: subval = subnode.serialize(null) children.append(subval) return children def _impl(self, node, value, callback): value = self._validate(node, value) error = None result = {} for num, subnode in enumerate(node.children): name = subnode.name subval = value.pop(name, null) if subval is drop or (subval is null and subnode.default is drop): continue try: sub_result = callback(subnode, subval) except Invalid as e: if error is None: error = Invalid(node) error.add(e, num) else: if sub_result is drop: continue result[name] = sub_result if self.unknown == 'raise': if value: raise UnsupportedFields( node, value, msg=_('Unrecognized keys in mapping: "${val}"', mapping={'val': value})) elif self.unknown == 'preserve': result.update(value) if error is not None: raise error return result def serialize(self, node, appstruct): if appstruct is null: appstruct = {} def callback(subnode, subappstruct): return subnode.serialize(subappstruct) return self._impl(node, appstruct, callback) def deserialize(self, node, cstruct): if cstruct is null: return null def callback(subnode, subcstruct): return subnode.deserialize(subcstruct) return self._impl(node, cstruct, callback) def flatten(self, node, appstruct, prefix='', listitem=False): result = {} if listitem: selfprefix = prefix else: if node.name: selfprefix = '%s%s.' % (prefix, node.name) else: selfprefix = prefix for subnode in node.children: name = subnode.name substruct = appstruct.get(name, null) result.update(subnode.typ.flatten(subnode, substruct, prefix=selfprefix)) return result def unflatten(self, node, paths, fstruct): return _unflatten_mapping(node, paths, fstruct) def set_value(self, node, appstruct, path, value): if '.' in path: next_name, rest = path.split('.', 1) next_node = node[next_name] next_appstruct = appstruct[next_name] appstruct[next_name] = next_node.typ.set_value( next_node, next_appstruct, rest, value) else: appstruct[path] = value return appstruct def get_value(self, node, appstruct, path): if '.' in path: name, rest = path.split('.', 1) next_node = node[name] return next_node.typ.get_value(next_node, appstruct[name], rest) return appstruct[path] class Positional(object): """ Marker abstract base class meaning 'this type has children which should be addressed by position instead of name' (e.g. via seq[0], but never seq['name']). This is consulted by Invalid.asdict when creating a dictionary representation of an error tree. """ class Tuple(Positional, SchemaType): """ A type which represents a fixed-length sequence of nodes. The subnodes of the :class:`colander.SchemaNode` that wraps this type imply the positional elements of the tuple in the order they are added. This type is willing to serialize and deserialized iterables that, when converted to a tuple, have the same number of elements as the number of the associated node's subnodes. If the :attr:`colander.null` value is passed to the serialize method of this class, the :attr:`colander.null` value will be returned. """ def _validate(self, node, value): if not hasattr(value, '__iter__'): raise Invalid( node, _('"${val}" is not iterable', mapping={'val':value}) ) valuelen, nodelen = len(value), len(node.children) if valuelen != nodelen: raise Invalid( node, _('"${val}" has an incorrect number of elements ' '(expected ${exp}, was ${was})', mapping={'val':value, 'exp':nodelen, 'was':valuelen}) ) return list(value) def cstruct_children(self, node, cstruct): childlen = len(node.children) if cstruct is null: cstruct = [] structlen = len(cstruct) if structlen < childlen: missing_children = node.children[structlen:] cstruct = list(cstruct) for child in missing_children: cstruct.append(child.serialize(null)) elif structlen > childlen: cstruct = cstruct[:childlen] else: cstruct = list(cstruct) return cstruct def _impl(self, node, value, callback): value = self._validate(node, value) error = None result = [] for num, subnode in enumerate(node.children): subval = value[num] try: result.append(callback(subnode, subval)) except Invalid as e: if error is None: error = Invalid(node) error.add(e, num) if error is not None: raise error return tuple(result) def serialize(self, node, appstruct): if appstruct is null: return null def callback(subnode, subappstruct): return subnode.serialize(subappstruct) return self._impl(node, appstruct, callback) def deserialize(self, node, cstruct): if cstruct is null: return null def callback(subnode, subval): return subnode.deserialize(subval) return self._impl(node, cstruct, callback) def flatten(self, node, appstruct, prefix='', listitem=False): result = {} if listitem: selfprefix = prefix else: selfprefix = '%s%s.' % (prefix, node.name) for num, subnode in enumerate(node.children): substruct = appstruct[num] result.update(subnode.typ.flatten(subnode, substruct, prefix=selfprefix)) return result def unflatten(self, node, paths, fstruct): mapstruct = _unflatten_mapping(node, paths, fstruct) appstruct = [] for subnode in node.children: appstruct.append(mapstruct[subnode.name]) return tuple(appstruct) def set_value(self, node, appstruct, path, value): appstruct = list(appstruct) if '.' in path: next_name, rest = path.split('.', 1) else: next_name, rest = path, None for index, next_node in enumerate(node.children): if next_node.name == next_name: break else: raise KeyError(next_name) if rest is not None: next_appstruct = appstruct[index] appstruct[index] = next_node.typ.set_value( next_node, next_appstruct, rest, value) else: appstruct[index] = value return tuple(appstruct) def get_value(self, node, appstruct, path): if '.' in path: name, rest = path.split('.', 1) else: name, rest = path, None for index, next_node in enumerate(node.children): if next_node.name == name: break else: raise KeyError(name) if rest is not None: return next_node.typ.get_value(next_node, appstruct[index], rest) return appstruct[index] class Set(SchemaType): """ A type representing a non-overlapping set of items. Deserializes an iterable to a ``set`` object. If the :attr:`colander.null` value is passed to the serialize method of this class, the :attr:`colander.null` value will be returned. .. versionadded: 1.0a1 """ def serialize(self, node, appstruct): if appstruct is null: return null return appstruct def deserialize(self, node, cstruct): if cstruct is null: return null if not is_nonstr_iter(cstruct): raise Invalid( node, _('${cstruct} is not iterable', mapping={'cstruct': cstruct}) ) return set(cstruct) class List(SchemaType): """ Type representing an ordered sequence of items. Desrializes an iterable to a ``list`` object. If the :attr:`colander.null` value is passed to the serialize method of this class, the :attr:`colander.null` value will be returned. .. versionadded: 1.0a6 """ def serialize(self, node, appstruct): if appstruct is null: return null return appstruct def deserialize(self, node, cstruct): if cstruct is null: return null if not is_nonstr_iter(cstruct): raise Invalid( node, _('${cstruct} is not iterable', mapping={'cstruct': cstruct}) ) return list(cstruct) class SequenceItems(list): """ List marker subclass for use by Sequence.cstruct_children, which indicates to a caller of that method that the result is from a sequence type. Usually these values need to be treated specially, because all of the children of a Sequence are not present in a schema. """ class Sequence(Positional, SchemaType): """ A type which represents a variable-length sequence of nodes, all of which must be of the same type. The type of the first subnode of the :class:`colander.SchemaNode` that wraps this type is considered the sequence type. The optional ``accept_scalar`` argument to this type's constructor indicates what should happen if the value found during serialization or deserialization does not have an ``__iter__`` method or is a mapping type. If ``accept_scalar`` is ``True`` and the value does not have an ``__iter__`` method or is a mapping type, the value will be turned into a single element list. If ``accept_scalar`` is ``False`` and the value does not have an ``__iter__`` method or is a mapping type, an :exc:`colander.Invalid` error will be raised during serialization and deserialization. The default value of ``accept_scalar`` is ``False``. If the :attr:`colander.null` value is passed to the serialize method of this class, the :attr:`colander.null` value is returned. """ def __init__(self, accept_scalar=False): self.accept_scalar = accept_scalar def _validate(self, node, value, accept_scalar): if (hasattr(value, '__iter__') and not hasattr(value, 'get') and not isinstance(value, string_types)): return list(value) if accept_scalar: return [value] else: raise Invalid(node, _('"${val}" is not iterable', mapping={'val':value}) ) def cstruct_children(self, node, cstruct): if cstruct is null: return SequenceItems([]) return SequenceItems(cstruct) def _impl(self, node, value, callback, accept_scalar): if accept_scalar is None: accept_scalar = self.accept_scalar value = self._validate(node, value, accept_scalar) error = None result = [] subnode = node.children[0] for num, subval in enumerate(value): if subval is drop or (subval is null and subnode.default is drop): continue try: sub_result = callback(subnode, subval) except Invalid as e: if error is None: error = Invalid(node) error.add(e, num) else: if sub_result is drop: continue result.append(sub_result) if error is not None: raise error return result def serialize(self, node, appstruct, accept_scalar=None): """ Along with the normal ``node`` and ``appstruct`` arguments, this method accepts an additional optional keyword argument: ``accept_scalar``. This keyword argument can be used to override the constructor value of the same name. If ``accept_scalar`` is ``True`` and the ``appstruct`` does not have an ``__iter__`` method or is a mapping type, the value will be turned into a single element list. If ``accept_scalar`` is ``False`` and the ``appstruct`` does not have an ``__iter__`` method or is a mapping type, an :exc:`colander.Invalid` error will be raised during serialization and deserialization. The default of ``accept_scalar`` is ``None``, which means respect the default ``accept_scalar`` value attached to this instance via its constructor. """ if appstruct is null: return null def callback(subnode, subappstruct): return subnode.serialize(subappstruct) return self._impl(node, appstruct, callback, accept_scalar) def deserialize(self, node, cstruct, accept_scalar=None): """ Along with the normal ``node`` and ``cstruct`` arguments, this method accepts an additional optional keyword argument: ``accept_scalar``. This keyword argument can be used to override the constructor value of the same name. If ``accept_scalar`` is ``True`` and the ``cstruct`` does not have an ``__iter__`` method or is a mapping type, the value will be turned into a single element list. If ``accept_scalar`` is ``False`` and the ``cstruct`` does not have an ``__iter__`` method or is a mapping type, an :exc:`colander.Invalid` error will be raised during serialization and deserialization. The default of ``accept_scalar`` is ``None``, which means respect the default ``accept_scalar`` value attached to this instance via its constructor. """ if cstruct is null: return null def callback(subnode, subcstruct): return subnode.deserialize(subcstruct) return self._impl(node, cstruct, callback, accept_scalar) def flatten(self, node, appstruct, prefix='', listitem=False): result = {} if listitem: selfprefix = prefix else: selfprefix = '%s%s.' % (prefix, node.name) childnode = node.children[0] for num, subval in enumerate(appstruct): subname = '%s%s' % (selfprefix, num) subprefix = subname + '.' result.update(childnode.typ.flatten( childnode, subval, prefix=subprefix, listitem=True)) return result def unflatten(self, node, paths, fstruct): only_child = node.children[0] child_name = only_child.name def get_child(name): return only_child def rewrite_subpath(subpath): if '.' in subpath: suffix = subpath.split('.', 1)[1] return '%s.%s' % (child_name, suffix) return child_name mapstruct = _unflatten_mapping(node, paths, fstruct, get_child, rewrite_subpath) return [mapstruct[str(index)] for index in xrange(len(mapstruct))] def set_value(self, node, appstruct, path, value): if '.' in path: next_name, rest = path.split('.', 1) index = int(next_name) next_node = node.children[0] next_appstruct = appstruct[index] appstruct[index] = next_node.typ.set_value( next_node, next_appstruct, rest, value) else: index = int(path) appstruct[index] = value return appstruct def get_value(self, node, appstruct, path): if '.' in path: name, rest = path.split('.', 1) index = int(name) next_node = node.children[0] return next_node.typ.get_value(next_node, appstruct[index], rest) return appstruct[int(path)] Seq = Sequence class String(SchemaType): """ A type representing a Unicode string. This type constructor accepts two arguments: ``encoding`` Represents the encoding which should be applied to value serialization and deserialization, for example ``utf-8``. If ``encoding`` is passed as ``None``, the ``serialize`` method of this type will not do any special encoding of the appstruct it is provided, nor will the ``deserialize`` method of this type do any special decoding of the cstruct it is provided; inputs and outputs will be assumed to be Unicode. ``encoding`` defaults to ``None``. If ``encoding`` is ``None``: - A Unicode input value to ``serialize`` is returned untouched. - A non-Unicode input value to ``serialize`` is run through the ``unicode()`` function without an ``encoding`` parameter (``unicode(value)``) and the result is returned. - A Unicode input value to ``deserialize`` is returned untouched. - A non-Unicode input value to ``deserialize`` is run through the ``unicode()`` function without an ``encoding`` parameter (``unicode(value)``) and the result is returned. If ``encoding`` is not ``None``: - A Unicode input value to ``serialize`` is run through the ``unicode`` function with the encoding parameter (``unicode(value, encoding)``) and the result (a ``str`` object) is returned. - A non-Unicode input value to ``serialize`` is converted to a Unicode using the encoding (``unicode(value, encoding)``); subsequently the Unicode object is re-encoded to a ``str`` object using the encoding and returned. - A Unicode input value to ``deserialize`` is returned untouched. - A non-Unicode input value to ``deserialize`` is converted to a ``str`` object using ``str(value``). The resulting str value is converted to Unicode using the encoding (``unicode(value, encoding)``) and the result is returned. A corollary: If a string (as opposed to a unicode object) is provided as a value to either the serialize or deserialize method of this type, and the type also has an non-None ``encoding``, the string must be encoded with the type's encoding. If this is not true, an :exc:`colander.Invalid` error will result. ``allow_empty`` Boolean, if True allows deserialization of an empty string. If False (default), empty strings will deserialize to :attr:`colander.null` The subnodes of the :class:`colander.SchemaNode` that wraps this type are ignored. """ def __init__(self, encoding=None, allow_empty=False): self.encoding = encoding self.allow_empty = allow_empty def serialize(self, node, appstruct): if appstruct is null: return null try: if isinstance(appstruct, (text_type, bytes)): encoding = self.encoding if encoding: result = text_(appstruct, encoding).encode(encoding) else: result = text_type(appstruct) else: result = text_type(appstruct) if self.encoding: result = result.encode(self.encoding) return result except Exception as e: raise Invalid(node, _('${val} cannot be serialized: ${err}', mapping={'val':appstruct, 'err':e}) ) def deserialize(self, node, cstruct): if cstruct == '' and self.allow_empty: return text_type('') if not cstruct: return null try: result = cstruct if isinstance(result, (text_type, bytes)): if self.encoding: result = text_(cstruct, self.encoding) else: result = text_type(cstruct) else: raise Invalid(node) except Exception as e: raise Invalid(node, _('${val} is not a string: ${err}', mapping={'val':cstruct, 'err':e})) return result Str = String class Number(SchemaType): """ Abstract base class for float, int, decimal """ num = None def serialize(self, node, appstruct): if appstruct is null: return null try: return str(self.num(appstruct)) except Exception: raise Invalid(node, _('"${val}" is not a number', mapping={'val':appstruct}), ) def deserialize(self, node, cstruct): if cstruct != 0 and not cstruct: return null try: return self.num(cstruct) except Exception: raise Invalid(node, _('"${val}" is not a number', mapping={'val':cstruct}) ) class Integer(Number): """ A type representing an integer. If the :attr:`colander.null` value is passed to the serialize method of this class, the :attr:`colander.null` value will be returned. The subnodes of the :class:`colander.SchemaNode` that wraps this type are ignored. """ num = int Int = Integer class Float(Number): """ A type representing a float. If the :attr:`colander.null` value is passed to the serialize method of this class, the :attr:`colander.null` value will be returned. The subnodes of the :class:`colander.SchemaNode` that wraps this type are ignored. """ num = float class Decimal(Number): """ A type representing a decimal floating point. Deserialization returns an instance of the Python ``decimal.Decimal`` type. If the :attr:`colander.null` value is passed to the serialize method of this class, the :attr:`colander.null` value will be returned. The Decimal constructor takes three optional arguments, ``quant``, ``rounding`` and ``normalize``. If supplied, ``quant`` should be a string, (e.g. ``1.00``). If supplied, ``rounding`` should be one of the Python ``decimal`` module rounding options (e.g. ``decimal.ROUND_UP``, ``decimal.ROUND_DOWN``, etc). The serialized and deserialized result will be quantized and rounded via ``result.quantize(decimal.Decimal(quant), rounding)``. ``rounding`` is ignored if ``quant`` is not supplied. If ``normalize`` is ``True``, the serialized and deserialized result will be normalized by stripping the rightmost trailing zeros. The subnodes of the :class:`colander.SchemaNode` that wraps this type are ignored. """ def __init__(self, quant=None, rounding=None, normalize=False): if quant is None: self.quant = None else: self.quant = decimal.Decimal(quant) self.rounding = rounding self.normalize = normalize def num(self, val): result = decimal.Decimal(str(val)) if self.quant is not None: if self.rounding is None: result = result.quantize(self.quant) else: result = result.quantize(self.quant, self.rounding) if self.normalize: result = result.normalize() return result class Money(Decimal): """ A type representing a money value with two digit precision. Deserialization returns an instance of the Python ``decimal.Decimal`` type (quantized to two decimal places, rounded up). If the :attr:`colander.null` value is passed to the serialize method of this class, the :attr:`colander.null` value will be returned. The subnodes of the :class:`colander.SchemaNode` that wraps this type are ignored. """ def __init__(self): super(Money, self).__init__(decimal.Decimal('.01'), decimal.ROUND_UP) class Boolean(SchemaType): """ A type representing a boolean object. The constructor accepts these keyword arguments: - ``false_choices``: The set of strings representing a ``False`` value on deserialization. - ``true_choices``: The set of strings representing a ``True`` value on deserialization. - ``false_val``: The value returned on serialization of a False value. - ``true_val``: The value returned on serialization of a True value. During deserialization, a value contained in :attr:`false_choices`, will be considered ``False``. The behaviour for values not contained in :attr:`false_choices` depends on :attr:`true_choices`: if it's empty, any value is considered ``True``; otherwise, only values contained in :attr:`true_choices` are considered ``True``, and an Invalid exception would be raised for values outside of both :attr:`false_choices` and :attr:`true_choices`. Serialization will produce :attr:`true_val` or :attr:`false_val` based on the value. If the :attr:`colander.null` value is passed to the serialize method of this class, the :attr:`colander.null` value will be returned. The subnodes of the :class:`colander.SchemaNode` that wraps this type are ignored. """ def __init__(self, false_choices=('false', '0'), true_choices=(), false_val='false', true_val='true'): self.false_choices = false_choices self.true_choices = true_choices self.false_val = false_val self.true_val = true_val self.true_reprs = ', '.join([repr(c) for c in self.true_choices]) self.false_reprs = ', '.join([repr(c) for c in self.false_choices]) def serialize(self, node, appstruct): if appstruct is null: return null return appstruct and self.true_val or self.false_val def deserialize(self, node, cstruct): if cstruct is null: return null try: result = str(cstruct) except: raise Invalid(node, _('${val} is not a string', mapping={'val':cstruct}) ) result = result.lower() if result in self.false_choices: return False elif self.true_choices: if result in self.true_choices: return True else: raise Invalid(node, _('"${val}" is neither in (${false_choices}) ' 'nor in (${true_choices})', mapping={'val':cstruct, 'false_choices': self.false_reprs, 'true_choices': self.true_reprs }) ) return True Bool = Boolean class GlobalObject(SchemaType): """ A type representing an importable Python object. This type serializes 'global' Python objects (objects which can be imported) to dotted Python names. Two dotted name styles are supported during deserialization: - ``pkg_resources``-style dotted names where non-module attributes of a module are separated from the rest of the path using a ':' e.g. ``package.module:attr``. - ``zope.dottedname``-style dotted names where non-module attributes of a module are separated from the rest of the path using a '.' e.g. ``package.module.attr``. These styles can be used interchangeably. If the serialization contains a ``:`` (colon), the ``pkg_resources`` resolution mechanism will be chosen, otherwise the ``zope.dottedname`` resolution mechanism will be chosen. The constructor accepts a single argument named ``package`` which should be a Python module or package object; it is used when *relative* dotted names are supplied to the ``deserialize`` method. A serialization which has a ``.`` (dot) or ``:`` (colon) as its first character is treated as relative. E.g. if ``.minidom`` is supplied to ``deserialize``, and the ``package`` argument to this type was passed the ``xml`` module object, the resulting import would be for ``xml.minidom``. If a relative package name is supplied to ``deserialize``, and no ``package`` was supplied to the constructor, an :exc:`colander.Invalid` error will be raised. If the :attr:`colander.null` value is passed to the serialize method of this class, the :attr:`colander.null` value will be returned. The subnodes of the :class:`colander.SchemaNode` that wraps this type are ignored. """ def __init__(self, package): self.package = package def _pkg_resources_style(self, node, value): """ package.module:attr style """ import pkg_resources if value.startswith('.') or value.startswith(':'): if not self.package: raise Invalid( node, _('relative name "${val}" irresolveable without package', mapping={'val':value}) ) if value in ['.', ':']: value = self.package.__name__ else: value = self.package.__name__ + value return pkg_resources.EntryPoint.parse( 'x=%s' % value).load(False) def _zope_dottedname_style(self, node, value): """ package.module.attr style """ module = self.package and self.package.__name__ or None if value == '.': if self.package is None: raise Invalid( node, _('relative name "${val}" irresolveable without package', mapping={'val':value}) ) name = module.split('.') else: name = value.split('.') if not name[0]: if module is None: raise Invalid( node, _('relative name "${val}" irresolveable without ' 'package', mapping={'val':value}) ) module = module.split('.') name.pop(0) while not name[0]: module.pop() name.pop(0) name = module + name used = name.pop(0) found = __import__(used) for n in name: used += '.' + n try: found = getattr(found, n) except AttributeError: # pragma: no cover __import__(used) found = getattr(found, n) return found def serialize(self, node, appstruct): if appstruct is null: return null try: if isinstance(appstruct, types.ModuleType): return appstruct.__name__ else: return '{0.__module__}.{0.__name__}'.format(appstruct) except AttributeError: raise Invalid(node, _('"${val}" has no __name__', mapping={'val':appstruct}) ) def deserialize(self, node, cstruct): if not cstruct: return null if not isinstance(cstruct, string_types): raise Invalid(node, _('"${val}" is not a string', mapping={'val':cstruct})) try: if ':' in cstruct: return self._pkg_resources_style(node, cstruct) else: return self._zope_dottedname_style(node, cstruct) except ImportError: raise Invalid(node, _('The dotted name "${name}" cannot be imported', mapping={'name':cstruct})) class DateTime(SchemaType): """ A type representing a Python ``datetime.datetime`` object. This type serializes python ``datetime.datetime`` objects to a `ISO8601 `_ string format. The format includes the date, the time, and the timezone of the datetime. The constructor accepts an argument named ``default_tzinfo`` which should be a Python ``tzinfo`` object. If ``default_tzinfo`` is not specified the default tzinfo will be equivalent to UTC (Zulu time). The ``default_tzinfo`` tzinfo object is used to convert 'naive' datetimes to a timezone-aware representation during serialization. If ``default_tzinfo`` is explicitly set to ``None`` then no default tzinfo will be applied to naive datetimes. You can adjust the error message reported by this class by changing its ``err_template`` attribute in a subclass on an instance of this class. By default, the ``err_template`` attribute is the string ``Invalid date``. This string is used as the interpolation subject of a dictionary composed of ``val`` and ``err``. ``val`` and ``err`` are the unvalidatable value and the exception caused trying to convert the value, respectively. These may be used in an overridden err_template as ``${val}`` and ``${err}`` respectively as necessary, e.g. ``_('${val} cannot be parsed as an iso8601 date: ${err}')``. For convenience, this type is also willing to coerce ``datetime.date`` objects to a DateTime ISO string representation during serialization. It does so by using midnight of the day as the time, and uses the ``default_tzinfo`` to give the serialization a timezone. Likewise, for convenience, during deserialization, this type will convert ``YYYY-MM-DD`` ISO8601 values to a datetime object. It does so by using midnight of the day as the time, and uses the ``default_tzinfo`` to give the serialization a timezone. If the :attr:`colander.null` value is passed to the serialize method of this class, the :attr:`colander.null` value will be returned. The subnodes of the :class:`colander.SchemaNode` that wraps this type are ignored. """ err_template = _('Invalid date') def __init__(self, default_tzinfo=iso8601.UTC): self.default_tzinfo = default_tzinfo def serialize(self, node, appstruct): if not appstruct: return null if type(appstruct) is datetime.date: # cant use isinstance; dt subs date appstruct = datetime.datetime.combine(appstruct, datetime.time()) if not isinstance(appstruct, datetime.datetime): raise Invalid(node, _('"${val}" is not a datetime object', mapping={'val':appstruct}) ) if appstruct.tzinfo is None: appstruct = appstruct.replace(tzinfo=self.default_tzinfo) return appstruct.isoformat() def deserialize(self, node, cstruct): if not cstruct: return null try: result = iso8601.parse_date( cstruct, default_timezone=self.default_tzinfo) except iso8601.ParseError as e: raise Invalid(node, _(self.err_template, mapping={'val':cstruct, 'err':e})) return result class Date(SchemaType): """ A type representing a Python ``datetime.date`` object. This type serializes python ``datetime.date`` objects to a `ISO8601 `_ string format. The format includes the date only. The constructor accepts no arguments. You can adjust the error message reported by this class by changing its ``err_template`` attribute in a subclass on an instance of this class. By default, the ``err_template`` attribute is the string ``Invalid date``. This string is used as the interpolation subject of a dictionary composed of ``val`` and ``err``. ``val`` and ``err`` are the unvalidatable value and the exception caused trying to convert the value, respectively. These may be used in an overridden err_template as ``${val}`` and ``${err}`` respectively as necessary, e.g. ``_('${val} cannot be parsed as an iso8601 date: ${err}')``. For convenience, this type is also willing to coerce ``datetime.datetime`` objects to a date-only ISO string representation during serialization. It does so by stripping off any time information, converting the ``datetime.datetime`` into a date before serializing. Likewise, for convenience, this type is also willing to coerce ISO representations that contain time info into a ``datetime.date`` object during deserialization. It does so by throwing away any time information related to the serialized value during deserialization. If the :attr:`colander.null` value is passed to the serialize method of this class, the :attr:`colander.null` value will be returned. The subnodes of the :class:`colander.SchemaNode` that wraps this type are ignored. """ err_template = _('Invalid date') def serialize(self, node, appstruct): if not appstruct: return null if isinstance(appstruct, datetime.datetime): appstruct = appstruct.date() if not isinstance(appstruct, datetime.date): raise Invalid(node, _('"${val}" is not a date object', mapping={'val':appstruct}) ) return appstruct.isoformat() def deserialize(self, node, cstruct): if not cstruct: return null try: result = iso8601.parse_date(cstruct) result = result.date() except iso8601.ParseError as e: raise Invalid(node, _(self.err_template, mapping={'val':cstruct, 'err':e}) ) return result class Time(SchemaType): """ A type representing a Python ``datetime.time`` object. .. note:: This type is new as of Colander 0.9.3. This type serializes python ``datetime.time`` objects to a `ISO8601 `_ string format. The format includes the time only. The constructor accepts no arguments. You can adjust the error message reported by this class by changing its ``err_template`` attribute in a subclass on an instance of this class. By default, the ``err_template`` attribute is the string ``Invalid date``. This string is used as the interpolation subject of a dictionary composed of ``val`` and ``err``. ``val`` and ``err`` are the unvalidatable value and the exception caused trying to convert the value, respectively. These may be used in an overridden err_template as ``${val}`` and ``${err}`` respectively as necessary, e.g. ``_('${val} cannot be parsed as an iso8601 date: ${err}')``. For convenience, this type is also willing to coerce ``datetime.datetime`` objects to a time-only ISO string representation during serialization. It does so by stripping off any date information, converting the ``datetime.datetime`` into a time before serializing. Likewise, for convenience, this type is also willing to coerce ISO representations that contain time info into a ``datetime.time`` object during deserialization. It does so by throwing away any date information related to the serialized value during deserialization. If the :attr:`colander.null` value is passed to the serialize method of this class, the :attr:`colander.null` value will be returned. The subnodes of the :class:`colander.SchemaNode` that wraps this type are ignored. """ err_template = _('Invalid time') def serialize(self, node, appstruct): if isinstance(appstruct, datetime.datetime): appstruct = appstruct.time() if not isinstance(appstruct, datetime.time): if not appstruct: return null raise Invalid(node, _('"${val}" is not a time object', mapping={'val':appstruct}) ) return appstruct.isoformat().split('.')[0] def deserialize(self, node, cstruct): if not cstruct: return null try: result = iso8601.parse_date(cstruct) result = result.time() except (iso8601.ParseError, TypeError): try: result = timeparse(cstruct, '%H:%M:%S') except ValueError: try: result = timeparse(cstruct, '%H:%M') except Exception as e: raise Invalid(node, _(self.err_template, mapping={'val':cstruct, 'err':e}) ) return result def timeparse(t, format): return datetime.datetime(*time.strptime(t, format)[0:6]).time() def _add_node_children(node, children): for n in children: insert_before = getattr(n, 'insert_before', None) exists = node.get(n.name, _marker) is not _marker # use exists for microspeed; we could just call __setitem__ # exclusively, but it does an enumeration that's unnecessary in the # common (nonexisting) case (.add is faster) if insert_before is None: if exists: node[n.name] = n else: node.add(n) else: if exists: del node[n.name] node.add_before(insert_before, n) class _SchemaNode(object): """ Fundamental building block of schemas. The constructor accepts these positional arguments: - ``typ``: The 'type' for this node. It should be an instance of a class that implements the :class:`colander.interfaces.Type` interface. If ``typ`` is not passed, a call to the ``schema_type()`` method on this class is made to get a default type. (When subclassing, ``schema_type()`` should be overridden to provide a reasonable default type). - ``*children``: a sequence of subnodes. If the subnodes of this node are not known at construction time, they can later be added via the ``add`` method. The constructor accepts these keyword arguments: - ``name``: The name of this node. - ``typ``: The 'type' for this node can optionally be passed in as a keyword argument. See the documentation for the positional arg above. - ``default``: The default serialization value for this node when not set. If ``default`` is :attr:`colander.drop`, the node will be dropped from schema serialization. If not provided, the node will be serialized to :attr:`colander.null`. - ``missing``: The default deserialization value for this node. If it is not provided, the missing value of this node will be the special marker value :attr:`colander.required`, indicating that it is considered 'required'. When ``missing`` is :attr:`colander.required`, the ``required`` computed attribute will be ``True``. When ``missing`` is :attr:`colander.drop`, the node is dropped from the schema if it isn't set during deserialization. - ``missing_msg``: Optional error message to be used if the value is required and missing. - ``preparer``: Optional preparer for this node. It should be an object that implements the :class:`colander.interfaces.Preparer` interface. - ``validator``: Optional validator for this node. It should be an object that implements the :class:`colander.interfaces.Validator` interface. - ``after_bind``: A callback which is called after a clone of this node has 'bound' all of its values successfully. This callback is useful for performing arbitrary actions to the cloned node, or direct children of the cloned node (such as removing or adding children) at bind time. A 'binding' is the result of an execution of the ``bind`` method of the clone's prototype node, or one of the parents of the clone's prototype nodes. The deepest nodes in the node tree are bound first, so the ``after_bind`` methods of the deepest nodes are called before the shallowest. The ``after_bind`` callback should accept two values: ``node`` and ``kw``. ``node`` will be a clone of the bound node object, ``kw`` will be the set of keywords passed to the ``bind`` method. - ``title``: The title of this node. Defaults to a titleization of the ``name`` (underscores replaced with empty strings and the first letter of every resulting word capitalized). The title is used by higher-level systems (not by Colander itself). - ``description``: The description for this node. Defaults to ``''`` (the empty string). The description is used by higher-level systems (not by Colander itself). - ``widget``: The 'widget' for this node. Defaults to ``None``. The widget attribute is not interpreted by Colander itself, it is only meaningful to higher-level systems such as Deform. - ``insert_before``: if supplied, it names a sibling defined by a superclass for its parent node; the current node will be inserted before the named node. It is not useful unless a mapping schema is inherited from another mapping schema, and you need to control the ordering of the resulting nodes. Arbitrary keyword arguments remaining will be attached to the node object unmolested. """ _counter = itertools.count() preparer = None validator = None default = null missing = required missing_msg = 'Required' name = '' raw_title = _marker # only changes if title is explicitly set title = _marker description = '' widget = None after_bind = None bindings = None def __new__(cls, *args, **kw): node = object.__new__(cls) node._order = next(cls._counter) node.children = [] _add_node_children(node, cls.__all_schema_nodes__) return node def __init__(self, *arg, **kw): # bw compat forces us to treat first arg as type if not a _SchemaNode if 'typ' in kw: self.typ = kw.pop('typ') elif arg and not isinstance(arg[0], _SchemaNode): self.typ, arg = arg[0], arg[1:] else: self.typ = self.schema_type() _add_node_children(self, arg) # bw compat forces us to manufacture a title if one is not supplied title = kw.get('title', self.title) if title is _marker: name = kw.get('name', self.name) kw['title'] = name.replace('_', ' ').title() else: kw['raw_title'] = title self.__dict__.update(kw) @staticmethod def schema_type(): raise NotImplementedError( 'Schema node construction without a `typ` argument or ' 'a schema_type() callable present on the node class ' ) @property def required(self): """ A property which returns ``True`` if the ``missing`` value related to this node was not specified. A return value of ``True`` implies that a ``missing`` value wasn't specified for this node or that the ``missing`` value of this node is :attr:`colander.required`. A return value of ``False`` implies that a 'real' ``missing`` value was specified for this node.""" if isinstance(self.missing, deferred): # unbound schema with deferreds return True return self.missing is required def serialize(self, appstruct=null): """ Serialize the :term:`appstruct` to a :term:`cstruct` based on the schema represented by this node and return the cstruct. If ``appstruct`` is :attr:`colander.null`, return the serialized value of this node's ``default`` attribute (by default, the serialization of :attr:`colander.null`). If an ``appstruct`` argument is not explicitly provided, it defaults to :attr:`colander.null`. """ if appstruct is null: appstruct = self.default if isinstance(appstruct, deferred): # unbound schema with deferreds appstruct = null cstruct = self.typ.serialize(self, appstruct) return cstruct def flatten(self, appstruct): """ Create and return a data structure which is a flattened representation of the passed in struct based on the schema represented by this node. The return data structure is a dictionary; its keys are dotted names. Each dotted name represents a path to a location in the schema. The values of of the flattened dictionary are subvalues of the passed in struct.""" flat = self.typ.flatten(self, appstruct) return flat def unflatten(self, fstruct): """ Create and return a data structure with nested substructures based on the schema represented by this node using the flattened representation passed in. This is the inverse operation to :meth:`colander.SchemaNode.flatten`.""" paths = sorted(fstruct.keys()) return self.typ.unflatten(self, paths, fstruct) def set_value(self, appstruct, dotted_name, value): """ Uses the schema to set a value in a nested datastructure from a dotted name path. """ self.typ.set_value(self, appstruct, dotted_name, value) def get_value(self, appstruct, dotted_name): """ Traverses the nested data structure using the schema and retrieves the value specified by the dotted name path.""" return self.typ.get_value(self, appstruct, dotted_name) def deserialize(self, cstruct=null): """ Deserialize the :term:`cstruct` into an :term:`appstruct` based on the schema, run this :term:`appstruct` through the preparer, if one is present, then validate the prepared appstruct. The ``cstruct`` value is deserialized into an ``appstruct`` unconditionally. If ``appstruct`` returned by type deserialization and preparation is the value :attr:`colander.null`, do something special before attempting validation: - If the ``missing`` attribute of this node has been set explicitly, return its value. No validation of this value is performed; it is simply returned. - If the ``missing`` attribute of this node has not been set explicitly, raise a :exc:`colander.Invalid` exception error. If the appstruct is not ``colander.null`` and cannot be validated , a :exc:`colander.Invalid` exception will be raised. If a ``cstruct`` argument is not explicitly provided, it defaults to :attr:`colander.null`. """ appstruct = self.typ.deserialize(self, cstruct) if self.preparer is not None: # if the preparer is a function, call a single preparer if hasattr(self.preparer, '__call__'): appstruct = self.preparer(appstruct) # if the preparer is a list, call each separate preparer elif is_nonstr_iter(self.preparer): for preparer in self.preparer: appstruct = preparer(appstruct) if appstruct is null: appstruct = self.missing if appstruct is required: raise Invalid(self, _(self.missing_msg, mapping={'title': self.title, 'name':self.name})) if isinstance(appstruct, deferred): # unbound schema with deferreds raise Invalid(self, self.missing_msg) # We never deserialize or validate the missing value return appstruct if self.validator is not None: if isinstance(self.validator, deferred): # unbound raise UnboundDeferredError( "Schema node {node} has an unbound deferred validator" .format(node=self)) self.validator(self, appstruct) return appstruct def add(self, node): """ Append a subnode to this node. ``node`` must be a SchemaNode.""" self.children.append(node) def insert(self, index, node): """ Insert a subnode into the position ``index``. ``node`` must be a SchemaNode.""" self.children.insert(index, node) def add_before(self, name, node): """ Insert a subnode into the position before the node named ``name`` """ for pos, sub in enumerate(self.children[:]): if sub.name == name: self.insert(pos, node) return raise KeyError('No such node named %s' % name) def get(self, name, default=None): """ Return the subnode associated with ``name`` or ``default`` if no such node exists.""" for node in self.children: if node.name == name: return node return default def clone(self): """ Clone the schema node and return the clone. All subnodes are also cloned recursively. Attributes present in node dictionaries are preserved.""" cloned = self.__class__(self.typ) cloned.__dict__.update(self.__dict__) cloned.children = [node.clone() for node in self.children] return cloned def bind(self, **kw): """ Resolve any deferred values attached to this schema node and its children (recursively), using the keywords passed as ``kw`` as input to each deferred value. This function *clones* the schema it is called upon and returns the cloned value. The original schema node (the source of the clone) is not modified.""" cloned = self.clone() cloned._bind(kw) return cloned def _bind(self, kw): self.bindings = kw for child in self.children: child._bind(kw) names = dir(self) for k in names: v = getattr(self, k) if isinstance(v, deferred): v = v(self, kw) if isinstance(v, SchemaNode): self[k] = v else: setattr(self, k, v) if getattr(self, 'after_bind', None): self.after_bind(self, kw) def cstruct_children(self, cstruct): """ Will call the node's type's ``cstruct_children`` method with this node as a first argument, and ``cstruct`` as a second argument.""" cstruct_children = getattr(self.typ, 'cstruct_children', None) if cstruct_children is None: warnings.warn( 'The node type %s has no cstruct_children method.' 'This method is required to be implemented by schema types for ' 'compatibility with Colander 0.9.9+. In a future Colander ' 'version, the absence of this method will cause an ' 'exception. Returning [] for compatibility although it ' 'may not be the right value.' % self.typ.__class__, DeprecationWarning, stacklevel=2 ) return [] return cstruct_children(self, cstruct) def __delitem__(self, name): """ Remove a subnode by name """ for idx, node in enumerate(self.children[:]): if node.name == name: return self.children.pop(idx) raise KeyError(name) def __getitem__(self, name): """ Get a subnode by name. """ val = self.get(name, _marker) if val is _marker: raise KeyError(name) return val def __setitem__(self, name, newnode): """ Replace a subnode by name. ``newnode`` must be a SchemaNode. If a subnode named ``name`` doesn't already exist, calling this method is the same as setting the node's name to ``name`` and calling the ``add`` method with the node (it will be appended to the children list).""" newnode.name = name for idx, node in enumerate(self.children[:]): if node.name == name: self.children[idx] = newnode return node self.add(newnode) def __iter__(self): """ Iterate over the children nodes of this schema node """ return iter(self.children) def __contains__(self, name): """ Return True if subnode named ``name`` exists in this node """ return self.get(name, _marker) is not _marker def __repr__(self): return '<%s.%s object at %d (named %s)>' % ( self.__module__, self.__class__.__name__, id(self), self.name, ) def raise_invalid(self, msg, node=None): """ Raise a :exc:`colander.Invalid` exception with the message ``msg``. ``node``, if supplied, should be an instance of a :class:`colander.SchemaNode`. If it is not supplied, ``node`` will be this node. Example usage:: class CustomSchemaNode(SchemaNode): def validator(self, node, cstruct): if cstruct != 'the_right_thing': self.raise_invalid('Not the right thing') """ if node is None: node = self raise Invalid(node, msg) class _SchemaMeta(type): def __init__(cls, name, bases, clsattrs): nodes = [] for name, value in clsattrs.items(): if isinstance(value, _SchemaNode): delattr(cls, name) if not value.name: value.name = name if value.raw_title is _marker: value.title = name.replace('_', ' ').title() nodes.append((value._order, value)) nodes.sort(key=lambda n: n[0]) cls.__class_schema_nodes__ = [ n[1] for n in nodes ] # Combine all attrs from this class and its _SchemaNode superclasses. cls.__all_schema_nodes__ = [] for c in reversed(cls.__mro__): csn = getattr(c, '__class_schema_nodes__', []) cls.__all_schema_nodes__.extend(csn) # metaclass spelling compatibility across Python 2 and Python 3 SchemaNode = _SchemaMeta( 'SchemaNode', (_SchemaNode,), {'__doc__': _SchemaNode.__doc__} ) class Schema(SchemaNode): schema_type = Mapping MappingSchema = Schema class TupleSchema(SchemaNode): schema_type = Tuple class SequenceSchema(SchemaNode): schema_type = Sequence def __init__(self, *args, **kw): SchemaNode.__init__(self, *args, **kw) if len(self.children) != 1: raise Invalid(self, 'Sequence schemas must have exactly one child node') def clone(self): """ Clone the schema node and return the clone. All subnodes are also cloned recursively. Attributes present in node dictionaries are preserved.""" # Cloning a ``SequenceSchema`` doesn't work with ``_SchemaNode.clone``. children = [node.clone() for node in self.children] cloned = self.__class__(self.typ, *children) attributes = self.__dict__.copy() attributes.pop('children', None) cloned.__dict__.update(attributes) return cloned class deferred(object): """ A decorator which can be used to define deferred schema values (missing values, widgets, validators, etc.)""" def __init__(self, wrapped): try: functools.update_wrapper(self, wrapped) except AttributeError: #non-function self.__doc__ = getattr(wrapped, '__doc__', None) self.wrapped = wrapped def __call__(self, node, kw): return self.wrapped(node, kw) def _unflatten_mapping(node, paths, fstruct, get_child=None, rewrite_subpath=None): if get_child is None: get_child = node.__getitem__ if rewrite_subpath is None: def rewrite_subpath(subpath): return subpath node_name = node.name if node_name: prefix = node_name + '.' else: prefix = '' prefix_len = len(prefix) appstruct = {} subfstruct = {} subpaths = [] curname = None for path in paths: if path == node_name: # flattened structs contain non-leaf nodes which are ignored # during unflattening. continue assert path.startswith(prefix), "Bad node: %s" % path subpath = path[prefix_len:] if '.' in subpath: name = subpath[:subpath.index('.')] else: name = subpath if curname is None: curname = name elif name != curname: subnode = get_child(curname) appstruct[curname] = subnode.typ.unflatten( subnode, subpaths, subfstruct) subfstruct = {} subpaths = [] curname = name subpath = rewrite_subpath(subpath) subfstruct[subpath] = fstruct[path] subpaths.append(subpath) if curname is not None: subnode = get_child(curname) appstruct[curname] = subnode.typ.unflatten( subnode, subpaths, subfstruct) return appstruct class instantiate(object): """ A decorator which can be used to instantiate :class:`SchemaNode` elements inline within a class definition. All parameters passed to the decorator and passed along to the :class:`SchemaNode` during instantiation. """ def __init__(self,*args,**kw): self.args,self.kw = args,kw def __call__(self,class_): return class_(*self.args,**self.kw)