Python collections.MutableMapping() Examples

def attributes(self):
        """The attributes of this name (:requires-ext:`rfc6680`)

        The attributes are presenting in the form of a
        :class:`~collections.MutableMapping` (a dict-like object).

        Retrieved values will always be in the form of :class:`frozensets`.

        When assigning values, if iterables are used, they be considered to be
        the set of values for the given attribute.  If a non-iterable is used,
        it will be considered a single value, and automatically wrapped in an
        iterable.

        Note:
            String types (includes :class:`bytes`) are not considered to
            be iterables in this case.
        """
        if self._attr_obj is None:
            raise NotImplementedError("Your GSSAPI implementation does not "
                                      "support RFC 6680 (the GSSAPI naming "
                                      "extensions)")

        return self._attr_obj 

def transform_incoming(self, son, collection):
        """Replace embedded documents with DBRefs.
        """

        def transform_value(value):
            if isinstance(value, collections.MutableMapping):
                if "_id" in value and "_ns" in value:
                    return DBRef(value["_ns"], transform_value(value["_id"]))
                else:
                    return transform_dict(SON(value))
            elif isinstance(value, list):
                return [transform_value(v) for v in value]
            return value

        def transform_dict(object):
            for (key, value) in object.items():
                object[key] = transform_value(value)
            return object

        return transform_dict(SON(son)) 

def view(tpl_name, **defaults):
    ''' Decorator: renders a template for a handler.
        The handler can control its behavior like that:

          - return a dict of template vars to fill out the template
          - return something other than a dict and the view decorator will not
            process the template, but return the handler result as is.
            This includes returning a HTTPResponse(dict) to get,
            for instance, JSON with autojson or other castfilters.
    '''
    def decorator(func):
        @functools.wraps(func)
        def wrapper(*args, **kwargs):
            result = func(*args, **kwargs)
            if isinstance(result, (dict, DictMixin)):
                tplvars = defaults.copy()
                tplvars.update(result)
                return template(tpl_name, **tplvars)
            elif result is None:
                return template(tpl_name, defaults)
            return result
        return wrapper
    return decorator 

def view(tpl_name, **defaults):
    ''' Decorator: renders a template for a handler.
        The handler can control its behavior like that:

          - return a dict of template vars to fill out the template
          - return something other than a dict and the view decorator will not
            process the template, but return the handler result as is.
            This includes returning a HTTPResponse(dict) to get,
            for instance, JSON with autojson or other castfilters.
    '''
    def decorator(func):
        @functools.wraps(func)
        def wrapper(*args, **kwargs):
            result = func(*args, **kwargs)
            if isinstance(result, (dict, DictMixin)):
                tplvars = defaults.copy()
                tplvars.update(result)
                return template(tpl_name, **tplvars)
            elif result is None:
                return template(tpl_name, defaults)
            return result
        return wrapper
    return decorator 

def view(tpl_name, **defaults):
    ''' Decorator: renders a template for a handler.
        The handler can control its behavior like that:

          - return a dict of template vars to fill out the template
          - return something other than a dict and the view decorator will not
            process the template, but return the handler result as is.
            This includes returning a HTTPResponse(dict) to get,
            for instance, JSON with autojson or other castfilters.
    '''
    def decorator(func):
        @functools.wraps(func)
        def wrapper(*args, **kwargs):
            result = func(*args, **kwargs)
            if isinstance(result, (dict, DictMixin)):
                tplvars = defaults.copy()
                tplvars.update(result)
                return template(tpl_name, **tplvars)
            elif result is None:
                return template(tpl_name, defaults)
            return result
        return wrapper
    return decorator 

def parse(cls, headers):
        """Returns a dictionary from HTTP header text.

        >>> h = HTTPHeaders.parse("Content-Type: text/html\\r\\nContent-Length: 42\\r\\n")
        >>> sorted(h.items())
        [('Content-Length', '42'), ('Content-Type', 'text/html')]

        .. versionchanged:: 5.1

           Raises `HTTPInputError` on malformed headers instead of a
           mix of `KeyError`, and `ValueError`.

        """
        h = cls()
        for line in _CRLF_RE.split(headers):
            if line:
                h.parse_line(line)
        return h

    # MutableMapping abstract method implementations. 

def add_field(self, name, type, key=False):
        '''
        Add a schema field

        Parameters
        ----------
        name : string
            Name of the field
        type : string
            Data type of the field
        key : bool, optional
            Indicates whether or not the field is a key field

        '''
        self.fields[name] = SchemaField(name, type, key=key)

#
# MutableMapping methods
# 

def view(tpl_name, **defaults):
    ''' Decorator: renders a template for a handler.
        The handler can control its behavior like that:

          - return a dict of template vars to fill out the template
          - return something other than a dict and the view decorator will not
            process the template, but return the handler result as is.
            This includes returning a HTTPResponse(dict) to get,
            for instance, JSON with autojson or other castfilters.
    '''
    def decorator(func):
        @functools.wraps(func)
        def wrapper(*args, **kwargs):
            result = func(*args, **kwargs)
            if isinstance(result, (dict, DictMixin)):
                tplvars = defaults.copy()
                tplvars.update(result)
                return template(tpl_name, **tplvars)
            elif result is None:
                return template(tpl_name, defaults)
            return result
        return wrapper
    return decorator 

def view(tpl_name, **defaults):
    ''' Decorator: renders a template for a handler.
        The handler can control its behavior like that:

          - return a dict of template vars to fill out the template
          - return something other than a dict and the view decorator will not
            process the template, but return the handler result as is.
            This includes returning a HTTPResponse(dict) to get,
            for instance, JSON with autojson or other castfilters.
    '''
    def decorator(func):
        @functools.wraps(func)
        def wrapper(*args, **kwargs):
            result = func(*args, **kwargs)
            if isinstance(result, (dict, DictMixin)):
                tplvars = defaults.copy()
                tplvars.update(result)
                return template(tpl_name, **tplvars)
            elif result is None:
                return template(tpl_name, defaults)
            return result
        return wrapper
    return decorator 

def flatten(dictionary, parent_key=False, separator='.'):
    """
    Turn a nested dictionary into a flattened dictionary

    :param dictionary: The dictionary to flatten
    :param parent_key: The string to prepend to dictionary's keys
    :param separator: The string used to separate flattened keys
    :return: A flattened dictionary
    """

    items = []
    for key, value in dictionary.items():
        new_key = str(parent_key) + separator + key if parent_key else key
        if isinstance(value, collections.MutableMapping):
            items.extend(flatten(value, new_key, separator).items())
        elif isinstance(value, list):
            for k, v in enumerate(value):
                items.extend(flatten({str(k): v}, new_key).items())
        else:
            items.append((new_key, value))
    return dict(items) 

def view(tpl_name, **defaults):
    ''' Decorator: renders a template for a handler.
        The handler can control its behavior like that:

          - return a dict of template vars to fill out the template
          - return something other than a dict and the view decorator will not
            process the template, but return the handler result as is.
            This includes returning a HTTPResponse(dict) to get,
            for instance, JSON with autojson or other castfilters.
    '''
    def decorator(func):
        @functools.wraps(func)
        def wrapper(*args, **kwargs):
            result = func(*args, **kwargs)
            if isinstance(result, (dict, DictMixin)):
                tplvars = defaults.copy()
                tplvars.update(result)
                return template(tpl_name, **tplvars)
            elif result is None:
                return template(tpl_name, defaults)
            return result
        return wrapper
    return decorator 

def view(tpl_name, **defaults):
    ''' Decorator: renders a template for a handler.
        The handler can control its behavior like that:

          - return a dict of template vars to fill out the template
          - return something other than a dict and the view decorator will not
            process the template, but return the handler result as is.
            This includes returning a HTTPResponse(dict) to get,
            for instance, JSON with autojson or other castfilters.
    '''
    def decorator(func):
        @functools.wraps(func)
        def wrapper(*args, **kwargs):
            result = func(*args, **kwargs)
            if isinstance(result, (dict, DictMixin)):
                tplvars = defaults.copy()
                tplvars.update(result)
                return template(tpl_name, **tplvars)
            elif result is None:
                return template(tpl_name, defaults)
            return result
        return wrapper
    return decorator 

def view(tpl_name, **defaults):
    ''' Decorator: renders a template for a handler.
        The handler can control its behavior like that:

          - return a dict of template vars to fill out the template
          - return something other than a dict and the view decorator will not
            process the template, but return the handler result as is.
            This includes returning a HTTPResponse(dict) to get,
            for instance, JSON with autojson or other castfilters.
    '''
    def decorator(func):
        @functools.wraps(func)
        def wrapper(*args, **kwargs):
            result = func(*args, **kwargs)
            if isinstance(result, (dict, DictMixin)):
                tplvars = defaults.copy()
                tplvars.update(result)
                return template(tpl_name, **tplvars)
            elif result is None:
                return template(tpl_name, defaults)
            return result
        return wrapper
    return decorator 

def __init__(self, func, items, cache=True):
        """Applies the given function on the given items at the moment of data request.

        On the moment one of the keys of this dict class is requested we apply the given function on the given items
        and return the result of that function. The advantage of this class is that it defers an expensive operation
        until it is needed.

        Items added to this dictionary after creation are assumed to be final, that is, we won't run the
        function on them.

        Args:
            func (Function): the callback function to apply on the given items at request, with signature:

                .. code-block:: python

                    def callback(key, value)

            items (collections.MutableMapping): the items on which we operate
            cache (boolean): if we want to cache computed results
        """
        self._func = func
        self._items = copy.copy(items)
        self._applied_on_key = {}
        self._cache = cache 

def view(tpl_name, **defaults):
    ''' Decorator: renders a template for a handler.
        The handler can control its behavior like that:

          - return a dict of template vars to fill out the template
          - return something other than a dict and the view decorator will not
            process the template, but return the handler result as is.
            This includes returning a HTTPResponse(dict) to get,
            for instance, JSON with autojson or other castfilters.
    '''
    def decorator(func):
        @functools.wraps(func)
        def wrapper(*args, **kwargs):
            result = func(*args, **kwargs)
            if isinstance(result, (dict, DictMixin)):
                tplvars = defaults.copy()
                tplvars.update(result)
                return template(tpl_name, **tplvars)
            return result
        return wrapper
    return decorator 

def update(self, *args, **kwargs):
        """Updates stored values.  Works like :func:`dict.update`."""
        if len(args) > 1:
            raise ValueError('update() takes at most one positional argument, '
                             '%d given.' % len(args))
        # We have this here instead of just letting MutableMapping.update()
        # handle things because it will iterate over keys and for each key
        # retrieve the value.  With Trie, this may be expensive since the path
        # to the node would have to be walked twice.  Instead, we have our own
        # implementation where iteritems() is used avoiding the unnecessary
        # value look-up.
        if args and isinstance(args[0], Trie):
            for key, value in _iteritems(args[0]):
                self[key] = value
            args = ()
        super(Trie, self).update(*args, **kwargs) 

def flatten_dict(d, parent_key='', sep='.'):
    """
    Remove the deep of a dictionary. All value are referenced by a key composed of all parent key (join by a dot).

    :param d: dictionary to flat
    :param parent_key: key of the parent of this dictionary
    :param sep: string to separate key and parent
    :return: the flat dictionary
    """
    items = []
    for k, v in d.items():
        new_key = parent_key + sep + k if parent_key else k
        if isinstance(v, collections.MutableMapping):
            items.extend(flatten_dict(v, new_key, sep=sep).items())
        else:
            items.append((new_key, v))
    return dict(items) 

def nested_dict_to_dot_map_dict(d, parent_key=''):
    """
    Convert a recursive dictionary into a flat, dot-map dictionary.

    :param d: e.g. {'a': {'b': 2, 'c': 3}}
    :param parent_key: Used for recursion
    :return: e.g. {'a.b': 2, 'a.c': 3}
    """
    items = []
    for k, v in d.items():
        new_key = parent_key + "." + k if parent_key else k
        if isinstance(v, collections.MutableMapping):
            items.extend(nested_dict_to_dot_map_dict(v, new_key).items())
        else:
            items.append((new_key, v))
    return dict(items) 

def parse(cls, headers):
        """Returns a dictionary from HTTP header text.

        >>> h = HTTPHeaders.parse("Content-Type: text/html\\r\\nContent-Length: 42\\r\\n")
        >>> sorted(h.items())
        [('Content-Length', '42'), ('Content-Type', 'text/html')]

        .. versionchanged:: 5.1

           Raises `HTTPInputError` on malformed headers instead of a
           mix of `KeyError`, and `ValueError`.

        """
        h = cls()
        for line in _CRLF_RE.split(headers):
            if line:
                h.parse_line(line)
        return h

    # MutableMapping abstract method implementations. 

def transform_outgoing(self, son, collection):
        """Replace DBRefs with embedded documents.
        """

        def transform_value(value):
            if isinstance(value, DBRef):
                return self.database.dereference(value)
            elif isinstance(value, list):
                return [transform_value(v) for v in value]
            elif isinstance(value, collections.MutableMapping):
                return transform_dict(SON(value))
            return value

        def transform_dict(object):
            for (key, value) in object.items():
                object[key] = transform_value(value)
            return object

        return transform_dict(SON(son))

# TODO make a generic translator for custom types. Take encode, decode,
# should_encode and should_decode functions and just encode and decode where
# necessary. See examples/custom_type.py for where this would be useful.
# Alternatively it could take a should_encode, to_binary, from_binary and
# binary subtype. 

def modifies_known_mutable(obj, attr):
    """This function checks if an attribute on a builtin mutable object
    (list, dict, set or deque) would modify it if called.  It also supports
    the "user"-versions of the objects (`sets.Set`, `UserDict.*` etc.) and
    with Python 2.6 onwards the abstract base classes `MutableSet`,
    `MutableMapping`, and `MutableSequence`.

    >>> modifies_known_mutable({}, "clear")
    True
    >>> modifies_known_mutable({}, "keys")
    False
    >>> modifies_known_mutable([], "append")
    True
    >>> modifies_known_mutable([], "index")
    False

    If called with an unsupported object (such as unicode) `False` is
    returned.

    >>> modifies_known_mutable("foo", "upper")
    False
    """
    for typespec, unsafe in _mutable_spec:
        if isinstance(obj, typespec):
            return attr in unsafe
    return False 

def __set__(self, instance, value):
        if isinstance(value, collections.MutableMapping):
            value = self.model(**value)

        super().__set__(instance, value) 

def _resolve(self, value):
        result = []
        for item in value:
            if item is None and self.skip_none:    # Skip none values
                continue

            if self.model and isinstance(item, collections.MutableMapping):
                item = self.model(**item)
            result.append(item)
        return result 

def copy(self):
        # defined in dict but not in MutableMapping.
        return HTTPHeaders(self)

    # Use our overridden copy method for the copy.copy module.
    # This makes shallow copies one level deeper, but preserves
    # the appearance that HTTPHeaders is a single container. 

def __new__(cls, document_class=dict,
                tz_aware=False, uuid_representation=PYTHON_LEGACY,
                unicode_decode_error_handler="strict",
                tzinfo=None):
        if not (issubclass(document_class, MutableMapping) or
                _raw_document_class(document_class)):
            raise TypeError("document_class must be dict, bson.son.SON, "
                            "bson.raw_bson_document.RawBSONDocument, or a "
                            "sublass of collections.MutableMapping")
        if not isinstance(tz_aware, bool):
            raise TypeError("tz_aware must be True or False")
        if uuid_representation not in ALL_UUID_REPRESENTATIONS:
            raise ValueError("uuid_representation must be a value "
                             "from bson.binary.ALL_UUID_REPRESENTATIONS")
        if not isinstance(unicode_decode_error_handler, (string_type, None)):
            raise ValueError("unicode_decode_error_handler must be a string "
                             "or None")
        if tzinfo is not None:
            if not isinstance(tzinfo, datetime.tzinfo):
                raise TypeError(
                    "tzinfo must be an instance of datetime.tzinfo")
            if not tz_aware:
                raise ValueError(
                    "cannot specify tzinfo without also setting tz_aware=True")

        return tuple.__new__(
            cls, (document_class, tz_aware, uuid_representation,
                  unicode_decode_error_handler, tzinfo)) 

def validate_is_document_type(option, value):
    """Validate the type of method arguments that expect a MongoDB document."""
    if not isinstance(value, (collections.MutableMapping, RawBSONDocument)):
        raise TypeError("%s must be an instance of dict, bson.son.SON, "
                        "bson.raw_bson.RawBSONDocument, or "
                        "a type that inherits from "
                        "collections.MutableMapping" % (option,)) 

def validate_document_class(option, value):
    """Validate the document_class option."""
    if not issubclass(value, (collections.MutableMapping, RawBSONDocument)):
        raise TypeError("%s must be dict, bson.son.SON, "
                        "bson.raw_bson.RawBSONDocument, or a "
                        "sublass of collections.MutableMapping" % (option,))
    return value 

def modifies_known_mutable(obj, attr):
    """This function checks if an attribute on a builtin mutable object
    (list, dict, set or deque) would modify it if called.  It also supports
    the "user"-versions of the objects (`sets.Set`, `UserDict.*` etc.) and
    with Python 2.6 onwards the abstract base classes `MutableSet`,
    `MutableMapping`, and `MutableSequence`.

    >>> modifies_known_mutable({}, "clear")
    True
    >>> modifies_known_mutable({}, "keys")
    False
    >>> modifies_known_mutable([], "append")
    True
    >>> modifies_known_mutable([], "index")
    False

    If called with an unsupported object (such as unicode) `False` is
    returned.

    >>> modifies_known_mutable("foo", "upper")
    False
    """
    for typespec, unsafe in _mutable_spec:
        if isinstance(obj, typespec):
            return attr in unsafe
    return False 

def __setattr__(self, key, value):
            if key in ('_config', '_prefix'):
                self.__dict__[key] = value
                return
            depr('Attribute assignment is deprecated.') #0.12
            if hasattr(DictMixin, key):
                raise AttributeError('Read-only attribute.')
            if key in self and self[key] and isinstance(self[key], self.__class__):
                raise AttributeError('Non-empty namespace attribute.')
            self[key] = value 

def modifies_known_mutable(obj, attr):
    """This function checks if an attribute on a builtin mutable object
    (list, dict, set or deque) would modify it if called.  It also supports
    the "user"-versions of the objects (`sets.Set`, `UserDict.*` etc.) and
    with Python 2.6 onwards the abstract base classes `MutableSet`,
    `MutableMapping`, and `MutableSequence`.

    >>> modifies_known_mutable({}, "clear")
    True
    >>> modifies_known_mutable({}, "keys")
    False
    >>> modifies_known_mutable([], "append")
    True
    >>> modifies_known_mutable([], "index")
    False

    If called with an unsupported object (such as unicode) `False` is
    returned.

    >>> modifies_known_mutable("foo", "upper")
    False
    """
    for typespec, unsafe in _mutable_spec:
        if isinstance(obj, typespec):
            return attr in unsafe
    return False