import datetime
import decimal
import itertools
import re
import socket
import time
import uuid
import warnings
from collections import Mapping
from operator import itemgetter
from bson import Binary, DBRef, ObjectId, SON
import gridfs
import pymongo
import six
try:
import dateutil
except ImportError:
dateutil = None
else:
import dateutil.parser
try:
from bson.int64 import Int64
except ImportError:
Int64 = long
from mongoengine.base import (BaseDocument, BaseField, ComplexBaseField,
GeoJsonBaseField, ObjectIdField, get_document)
from mongoengine.connection import DEFAULT_CONNECTION_NAME, get_db
from mongoengine.document import Document, EmbeddedDocument
from mongoengine.errors import DoesNotExist, InvalidQueryError, ValidationError
from mongoengine.python_support import StringIO
from mongoengine.queryset import DO_NOTHING, QuerySet
try:
from PIL import Image, ImageOps
except ImportError:
Image = None
ImageOps = None
__all__ = (
'StringField', 'URLField', 'EmailField', 'IntField', 'LongField',
'FloatField', 'DecimalField', 'BooleanField', 'DateTimeField',
'ComplexDateTimeField', 'EmbeddedDocumentField', 'ObjectIdField',
'GenericEmbeddedDocumentField', 'DynamicField', 'ListField',
'SortedListField', 'EmbeddedDocumentListField', 'DictField',
'MapField', 'ReferenceField', 'CachedReferenceField',
'GenericReferenceField', 'BinaryField', 'GridFSError', 'GridFSProxy',
'FileField', 'ImageGridFsProxy', 'ImproperlyConfigured', 'ImageField',
'GeoPointField', 'PointField', 'LineStringField', 'PolygonField',
'SequenceField', 'UUIDField', 'MultiPointField', 'MultiLineStringField',
'MultiPolygonField', 'GeoJsonBaseField'
)
RECURSIVE_REFERENCE_CONSTANT = 'self'
class StringField(BaseField):
"""A unicode string field."""
def __init__(self, regex=None, max_length=None, min_length=None, **kwargs):
self.regex = re.compile(regex) if regex else None
self.max_length = max_length
self.min_length = min_length
super(StringField, self).__init__(**kwargs)
def to_python(self, value):
if isinstance(value, six.text_type):
return value
try:
value = value.decode('utf-8')
except Exception:
pass
return value
def validate(self, value):
if not isinstance(value, six.string_types):
self.error('StringField only accepts string values')
if self.max_length is not None and len(value) > self.max_length:
self.error('String value is too long')
if self.min_length is not None and len(value) < self.min_length:
self.error('String value is too short')
if self.regex is not None and self.regex.match(value) is None:
self.error('String value did not match validation regex')
def lookup_member(self, member_name):
return None
def prepare_query_value(self, op, value):
if not isinstance(op, six.string_types):
return value
if op.lstrip('i') in ('startswith', 'endswith', 'contains', 'exact'):
flags = 0
if op.startswith('i'):
flags = re.IGNORECASE
op = op.lstrip('i')
regex = r'%s'
if op == 'startswith':
regex = r'^%s'
elif op == 'endswith':
regex = r'%s$'
elif op == 'exact':
regex = r'^%s$'
# escape unsafe characters which could lead to a re.error
value = re.escape(value)
value = re.compile(regex % value, flags)
return super(StringField, self).prepare_query_value(op, value)
class URLField(StringField):
"""A field that validates input as an URL.
.. versionadded:: 0.3
"""
_URL_REGEX = re.compile(
r'^(?:[a-z0-9\.\-]*)://' # scheme is validated separately
r'(?:(?:[A-Z0-9](?:[A-Z0-9-]{0,61}[A-Z0-9])?\.)+(?:[A-Z]{2,6}\.?|[A-Z0-9-]{2,}(?<!-)\.?)|' # domain...
r'localhost|' # localhost...
r'\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}|' # ...or ipv4
r'\[?[A-F0-9]*:[A-F0-9:]+\]?)' # ...or ipv6
r'(?::\d+)?' # optional port
r'(?:/?|[/?]\S+)$', re.IGNORECASE)
_URL_SCHEMES = ['http', 'https', 'ftp', 'ftps']
def __init__(self, verify_exists=False, url_regex=None, schemes=None, **kwargs):
self.verify_exists = verify_exists
self.url_regex = url_regex or self._URL_REGEX
self.schemes = schemes or self._URL_SCHEMES
super(URLField, self).__init__(**kwargs)
def validate(self, value):
# Check first if the scheme is valid
scheme = value.split('://')[0].lower()
if scheme not in self.schemes:
self.error(u'Invalid scheme {} in URL: {}'.format(scheme, value))
return
# Then check full URL
if not self.url_regex.match(value):
self.error(u'Invalid URL: {}'.format(value))
return
class EmailField(StringField):
"""A field that validates input as an email address.
.. versionadded:: 0.4
"""
USER_REGEX = re.compile(
# `dot-atom` defined in RFC 5322 Section 3.2.3.
r"(^[-!#$%&'*+/=?^_`{}|~0-9A-Z]+(\.[-!#$%&'*+/=?^_`{}|~0-9A-Z]+)*\Z"
# `quoted-string` defined in RFC 5322 Section 3.2.4.
r'|^"([\001-\010\013\014\016-\037!#-\[\]-\177]|\\[\001-\011\013\014\016-\177])*"\Z)',
re.IGNORECASE
)
UTF8_USER_REGEX = re.compile(
six.u(
# RFC 6531 Section 3.3 extends `atext` (used by dot-atom) to
# include `UTF8-non-ascii`.
r"(^[-!#$%&'*+/=?^_`{}|~0-9A-Z\u0080-\U0010FFFF]+(\.[-!#$%&'*+/=?^_`{}|~0-9A-Z\u0080-\U0010FFFF]+)*\Z"
# `quoted-string`
r'|^"([\001-\010\013\014\016-\037!#-\[\]-\177]|\\[\001-\011\013\014\016-\177])*"\Z)'
), re.IGNORECASE | re.UNICODE
)
DOMAIN_REGEX = re.compile(
r'((?:[A-Z0-9](?:[A-Z0-9-]{0,61}[A-Z0-9])?\.)+)(?:[A-Z0-9-]{2,63}(?<!-))\Z',
re.IGNORECASE
)
error_msg = u'Invalid email address: %s'
def __init__(self, domain_whitelist=None, allow_utf8_user=False,
allow_ip_domain=False, *args, **kwargs):
"""Initialize the EmailField.
Args:
domain_whitelist (list) - list of otherwise invalid domain
names which you'd like to support.
allow_utf8_user (bool) - if True, the user part of the email
address can contain UTF8 characters.
False by default.
allow_ip_domain (bool) - if True, the domain part of the email
can be a valid IPv4 or IPv6 address.
"""
self.domain_whitelist = domain_whitelist or []
self.allow_utf8_user = allow_utf8_user
self.allow_ip_domain = allow_ip_domain
super(EmailField, self).__init__(*args, **kwargs)
def validate_user_part(self, user_part):
"""Validate the user part of the email address. Return True if
valid and False otherwise.
"""
if self.allow_utf8_user:
return self.UTF8_USER_REGEX.match(user_part)
return self.USER_REGEX.match(user_part)
def validate_domain_part(self, domain_part):
"""Validate the domain part of the email address. Return True if
valid and False otherwise.
"""
# Skip domain validation if it's in the whitelist.
if domain_part in self.domain_whitelist:
return True
if self.DOMAIN_REGEX.match(domain_part):
return True
# Validate IPv4/IPv6, e.g. user@[192.168.0.1]
if (
self.allow_ip_domain and
domain_part[0] == '[' and
domain_part[-1] == ']'
):
for addr_family in (socket.AF_INET, socket.AF_INET6):
try:
socket.inet_pton(addr_family, domain_part[1:-1])
return True
except (socket.error, UnicodeEncodeError):
pass
return False
def validate(self, value):
super(EmailField, self).validate(value)
if '@' not in value:
self.error(self.error_msg % value)
user_part, domain_part = value.rsplit('@', 1)
# Validate the user part.
if not self.validate_user_part(user_part):
self.error(self.error_msg % value)
# Validate the domain and, if invalid, see if it's IDN-encoded.
if not self.validate_domain_part(domain_part):
try:
domain_part = domain_part.encode('idna').decode('ascii')
except UnicodeError:
self.error(self.error_msg % value)
else:
if not self.validate_domain_part(domain_part):
self.error(self.error_msg % value)
class IntField(BaseField):
"""32-bit integer field."""
def __init__(self, min_value=None, max_value=None, **kwargs):
self.min_value, self.max_value = min_value, max_value
super(IntField, self).__init__(**kwargs)
def to_python(self, value):
try:
value = int(value)
except ValueError:
pass
return value
def validate(self, value):
try:
value = int(value)
except Exception:
self.error('%s could not be converted to int' % value)
if self.min_value is not None and value < self.min_value:
self.error('Integer value is too small')
if self.max_value is not None and value > self.max_value:
self.error('Integer value is too large')
def prepare_query_value(self, op, value):
if value is None:
return value
return super(IntField, self).prepare_query_value(op, int(value))
class LongField(BaseField):
"""64-bit integer field."""
def __init__(self, min_value=None, max_value=None, **kwargs):
self.min_value, self.max_value = min_value, max_value
super(LongField, self).__init__(**kwargs)
def to_python(self, value):
try:
value = long(value)
except ValueError:
pass
return value
def to_mongo(self, value):
return Int64(value)
def validate(self, value):
try:
value = long(value)
except Exception:
self.error('%s could not be converted to long' % value)
if self.min_value is not None and value < self.min_value:
self.error('Long value is too small')
if self.max_value is not None and value > self.max_value:
self.error('Long value is too large')
def prepare_query_value(self, op, value):
if value is None:
return value
return super(LongField, self).prepare_query_value(op, long(value))
class FloatField(BaseField):
"""Floating point number field."""
def __init__(self, min_value=None, max_value=None, **kwargs):
self.min_value, self.max_value = min_value, max_value
super(FloatField, self).__init__(**kwargs)
def to_python(self, value):
try:
value = float(value)
except ValueError:
pass
return value
def validate(self, value):
if isinstance(value, six.integer_types):
try:
value = float(value)
except OverflowError:
self.error('The value is too large to be converted to float')
if not isinstance(value, float):
self.error('FloatField only accepts float and integer values')
if self.min_value is not None and value < self.min_value:
self.error('Float value is too small')
if self.max_value is not None and value > self.max_value:
self.error('Float value is too large')
def prepare_query_value(self, op, value):
if value is None:
return value
return super(FloatField, self).prepare_query_value(op, float(value))
class DecimalField(BaseField):
"""Fixed-point decimal number field.
.. versionchanged:: 0.8
.. versionadded:: 0.3
"""
def __init__(self, min_value=None, max_value=None, force_string=False,
precision=2, rounding=decimal.ROUND_HALF_UP, **kwargs):
"""
:param min_value: Validation rule for the minimum acceptable value.
:param max_value: Validation rule for the maximum acceptable value.
:param force_string: Store as a string.
:param precision: Number of decimal places to store.
:param rounding: The rounding rule from the python decimal library:
- decimal.ROUND_CEILING (towards Infinity)
- decimal.ROUND_DOWN (towards zero)
- decimal.ROUND_FLOOR (towards -Infinity)
- decimal.ROUND_HALF_DOWN (to nearest with ties going towards zero)
- decimal.ROUND_HALF_EVEN (to nearest with ties going to nearest even integer)
- decimal.ROUND_HALF_UP (to nearest with ties going away from zero)
- decimal.ROUND_UP (away from zero)
- decimal.ROUND_05UP (away from zero if last digit after rounding towards zero would have been 0 or 5; otherwise towards zero)
Defaults to: ``decimal.ROUND_HALF_UP``
"""
self.min_value = min_value
self.max_value = max_value
self.force_string = force_string
self.precision = precision
self.rounding = rounding
super(DecimalField, self).__init__(**kwargs)
def to_python(self, value):
if value is None:
return value
# Convert to string for python 2.6 before casting to Decimal
try:
value = decimal.Decimal('%s' % value)
except decimal.InvalidOperation:
return value
return value.quantize(decimal.Decimal('.%s' % ('0' * self.precision)), rounding=self.rounding)
def to_mongo(self, value):
if value is None:
return value
if self.force_string:
return six.text_type(self.to_python(value))
return float(self.to_python(value))
def validate(self, value):
if not isinstance(value, decimal.Decimal):
if not isinstance(value, six.string_types):
value = six.text_type(value)
try:
value = decimal.Decimal(value)
except Exception as exc:
self.error('Could not convert value to decimal: %s' % exc)
if self.min_value is not None and value < self.min_value:
self.error('Decimal value is too small')
if self.max_value is not None and value > self.max_value:
self.error('Decimal value is too large')
def prepare_query_value(self, op, value):
return super(DecimalField, self).prepare_query_value(op, self.to_mongo(value))
class BooleanField(BaseField):
"""Boolean field type.
.. versionadded:: 0.1.2
"""
def to_python(self, value):
try:
value = bool(value)
except ValueError:
pass
return value
def validate(self, value):
if not isinstance(value, bool):
self.error('BooleanField only accepts boolean values')
class DateTimeField(BaseField):
"""Datetime field.
Uses the python-dateutil library if available alternatively use time.strptime
to parse the dates. Note: python-dateutil's parser is fully featured and when
installed you can utilise it to convert varying types of date formats into valid
python datetime objects.
Note: Microseconds are rounded to the nearest millisecond.
Pre UTC microsecond support is effectively broken.
Use :class:`~mongoengine.fields.ComplexDateTimeField` if you
need accurate microsecond support.
"""
def validate(self, value):
new_value = self.to_mongo(value)
if not isinstance(new_value, (datetime.datetime, datetime.date)):
self.error(u'cannot parse date "%s"' % value)
def to_mongo(self, value):
if value is None:
return value
if isinstance(value, datetime.datetime):
return value
if isinstance(value, datetime.date):
return datetime.datetime(value.year, value.month, value.day)
if callable(value):
return value()
if not isinstance(value, six.string_types):
return None
# Attempt to parse a datetime:
if dateutil:
try:
return dateutil.parser.parse(value)
except (TypeError, ValueError):
return None
# split usecs, because they are not recognized by strptime.
if '.' in value:
try:
value, usecs = value.split('.')
usecs = int(usecs)
except ValueError:
return None
else:
usecs = 0
kwargs = {'microsecond': usecs}
try: # Seconds are optional, so try converting seconds first.
return datetime.datetime(*time.strptime(value,
'%Y-%m-%d %H:%M:%S')[:6], **kwargs)
except ValueError:
try: # Try without seconds.
return datetime.datetime(*time.strptime(value,
'%Y-%m-%d %H:%M')[:5], **kwargs)
except ValueError: # Try without hour/minutes/seconds.
try:
return datetime.datetime(*time.strptime(value,
'%Y-%m-%d')[:3], **kwargs)
except ValueError:
return None
def prepare_query_value(self, op, value):
return super(DateTimeField, self).prepare_query_value(op, self.to_mongo(value))
class ComplexDateTimeField(StringField):
"""
ComplexDateTimeField handles microseconds exactly instead of rounding
like DateTimeField does.
Derives from a StringField so you can do `gte` and `lte` filtering by
using lexicographical comparison when filtering / sorting strings.
The stored string has the following format:
YYYY,MM,DD,HH,MM,SS,NNNNNN
Where NNNNNN is the number of microseconds of the represented `datetime`.
The `,` as the separator can be easily modified by passing the `separator`
keyword when initializing the field.
.. versionadded:: 0.5
"""
def __init__(self, separator=',', **kwargs):
self.names = ['year', 'month', 'day', 'hour', 'minute', 'second', 'microsecond']
self.separator = separator
self.format = separator.join(['%Y', '%m', '%d', '%H', '%M', '%S', '%f'])
super(ComplexDateTimeField, self).__init__(**kwargs)
def _convert_from_datetime(self, val):
"""
Convert a `datetime` object to a string representation (which will be
stored in MongoDB). This is the reverse function of
`_convert_from_string`.
>>> a = datetime(2011, 6, 8, 20, 26, 24, 92284)
>>> ComplexDateTimeField()._convert_from_datetime(a)
'2011,06,08,20,26,24,092284'
"""
return val.strftime(self.format)
def _convert_from_string(self, data):
"""
Convert a string representation to a `datetime` object (the object you
will manipulate). This is the reverse function of
`_convert_from_datetime`.
>>> a = '2011,06,08,20,26,24,092284'
>>> ComplexDateTimeField()._convert_from_string(a)
datetime.datetime(2011, 6, 8, 20, 26, 24, 92284)
"""
values = map(int, data.split(self.separator))
return datetime.datetime(*values)
def __get__(self, instance, owner):
data = super(ComplexDateTimeField, self).__get__(instance, owner)
if data is None:
return None if self.null else datetime.datetime.now()
if isinstance(data, datetime.datetime):
return data
return self._convert_from_string(data)
def __set__(self, instance, value):
value = self._convert_from_datetime(value) if value else value
return super(ComplexDateTimeField, self).__set__(instance, value)
def validate(self, value):
value = self.to_python(value)
if not isinstance(value, datetime.datetime):
self.error('Only datetime objects may used in a '
'ComplexDateTimeField')
def to_python(self, value):
original_value = value
try:
return self._convert_from_string(value)
except Exception:
return original_value
def to_mongo(self, value):
value = self.to_python(value)
return self._convert_from_datetime(value)
def prepare_query_value(self, op, value):
return super(ComplexDateTimeField, self).prepare_query_value(op, self._convert_from_datetime(value))
class EmbeddedDocumentField(BaseField):
"""An embedded document field - with a declared document_type.
Only valid values are subclasses of :class:`~mongoengine.EmbeddedDocument`.
"""
def __init__(self, document_type, **kwargs):
if (
not isinstance(document_type, six.string_types) and
not issubclass(document_type, EmbeddedDocument)
):
self.error('Invalid embedded document class provided to an '
'EmbeddedDocumentField')
self.document_type_obj = document_type
super(EmbeddedDocumentField, self).__init__(**kwargs)
@property
def document_type(self):
if isinstance(self.document_type_obj, six.string_types):
if self.document_type_obj == RECURSIVE_REFERENCE_CONSTANT:
self.document_type_obj = self.owner_document
else:
self.document_type_obj = get_document(self.document_type_obj)
return self.document_type_obj
def to_python(self, value):
if not isinstance(value, self.document_type):
return self.document_type._from_son(value, _auto_dereference=self._auto_dereference)
return value
def to_mongo(self, value, use_db_field=True, fields=None):
if not isinstance(value, self.document_type):
return value
return self.document_type.to_mongo(value, use_db_field, fields)
def validate(self, value, clean=True):
"""Make sure that the document instance is an instance of the
EmbeddedDocument subclass provided when the document was defined.
"""
# Using isinstance also works for subclasses of self.document
if not isinstance(value, self.document_type):
self.error('Invalid embedded document instance provided to an '
'EmbeddedDocumentField')
self.document_type.validate(value, clean)
def lookup_member(self, member_name):
return self.document_type._fields.get(member_name)
def prepare_query_value(self, op, value):
if value is not None and not isinstance(value, self.document_type):
try:
value = self.document_type._from_son(value)
except ValueError:
raise InvalidQueryError("Querying the embedded document '%s' failed, due to an invalid query value" %
(self.document_type._class_name,))
super(EmbeddedDocumentField, self).prepare_query_value(op, value)
return self.to_mongo(value)
class GenericEmbeddedDocumentField(BaseField):
"""A generic embedded document field - allows any
:class:`~mongoengine.EmbeddedDocument` to be stored.
Only valid values are subclasses of :class:`~mongoengine.EmbeddedDocument`.
.. note ::
You can use the choices param to limit the acceptable
EmbeddedDocument types
"""
def prepare_query_value(self, op, value):
return super(GenericEmbeddedDocumentField, self).prepare_query_value(op, self.to_mongo(value))
def to_python(self, value):
if isinstance(value, dict):
doc_cls = get_document(value['_cls'])
value = doc_cls._from_son(value)
return value
def validate(self, value, clean=True):
if not isinstance(value, EmbeddedDocument):
self.error('Invalid embedded document instance provided to an '
'GenericEmbeddedDocumentField')
value.validate(clean=clean)
def to_mongo(self, document, use_db_field=True, fields=None):
if document is None:
return None
data = document.to_mongo(use_db_field, fields)
if '_cls' not in data:
data['_cls'] = document._class_name
return data
class DynamicField(BaseField):
"""A truly dynamic field type capable of handling different and varying
types of data.
Used by :class:`~mongoengine.DynamicDocument` to handle dynamic data"""
def __init__(self, container_class=dict, *args, **kwargs):
self._container_cls = container_class
if not issubclass(self._container_cls, Mapping):
self.error('The class that is specified in `container_class` parameter '
'must be a subclass of `dict`.')
super(DynamicField, self).__init__(*args, **kwargs)
def to_mongo(self, value, use_db_field=True, fields=None):
"""Convert a Python type to a MongoDB compatible type.
"""
if isinstance(value, six.string_types):
return value
if hasattr(value, 'to_mongo'):
cls = value.__class__
val = value.to_mongo(use_db_field, fields)
# If we its a document thats not inherited add _cls
if isinstance(value, Document):
val = {'_ref': value.to_dbref(), '_cls': cls.__name__}
if isinstance(value, EmbeddedDocument):
val['_cls'] = cls.__name__
return val
if not isinstance(value, (dict, list, tuple)):
return value
is_list = False
if not hasattr(value, 'items'):
is_list = True
value = {k: v for k, v in enumerate(value)}
data = self._container_cls()
for k, v in value.iteritems():
data[k] = self.to_mongo(v, use_db_field, fields)
value = data
if is_list: # Convert back to a list
value = [v for k, v in sorted(data.iteritems(), key=itemgetter(0))]
return value
def to_python(self, value):
if isinstance(value, dict) and '_cls' in value:
doc_cls = get_document(value['_cls'])
if '_ref' in value:
value = doc_cls._get_db().dereference(value['_ref'])
return doc_cls._from_son(value)
return super(DynamicField, self).to_python(value)
def lookup_member(self, member_name):
return member_name
def prepare_query_value(self, op, value):
if isinstance(value, six.string_types):
return StringField().prepare_query_value(op, value)
return super(DynamicField, self).prepare_query_value(op, self.to_mongo(value))
def validate(self, value, clean=True):
if hasattr(value, 'validate'):
value.validate(clean=clean)
class ListField(ComplexBaseField):
"""A list field that wraps a standard field, allowing multiple instances
of the field to be used as a list in the database.
If using with ReferenceFields see: :ref:`one-to-many-with-listfields`
.. note::
Required means it cannot be empty - as the default for ListFields is []
"""
def __init__(self, field=None, **kwargs):
self.field = field
kwargs.setdefault('default', lambda: [])
super(ListField, self).__init__(**kwargs)
def validate(self, value):
"""Make sure that a list of valid fields is being used."""
if (not isinstance(value, (list, tuple, QuerySet)) or
isinstance(value, six.string_types)):
self.error('Only lists and tuples may be used in a list field')
super(ListField, self).validate(value)
def prepare_query_value(self, op, value):
if self.field:
# If the value is iterable and it's not a string nor a
# BaseDocument, call prepare_query_value for each of its items.
if (
op in ('set', 'unset', None) and
hasattr(value, '__iter__') and
not isinstance(value, six.string_types) and
not isinstance(value, BaseDocument)
):
return [self.field.prepare_query_value(op, v) for v in value]
return self.field.prepare_query_value(op, value)
return super(ListField, self).prepare_query_value(op, value)
class EmbeddedDocumentListField(ListField):
"""A :class:`~mongoengine.ListField` designed specially to hold a list of
embedded documents to provide additional query helpers.
.. note::
The only valid list values are subclasses of
:class:`~mongoengine.EmbeddedDocument`.
.. versionadded:: 0.9
"""
def __init__(self, document_type, **kwargs):
"""
:param document_type: The type of
:class:`~mongoengine.EmbeddedDocument` the list will hold.
:param kwargs: Keyword arguments passed directly into the parent
:class:`~mongoengine.ListField`.
"""
super(EmbeddedDocumentListField, self).__init__(
field=EmbeddedDocumentField(document_type), **kwargs
)
class SortedListField(ListField):
"""A ListField that sorts the contents of its list before writing to
the database in order to ensure that a sorted list is always
retrieved.
.. warning::
There is a potential race condition when handling lists. If you set /
save the whole list then other processes trying to save the whole list
as well could overwrite changes. The safest way to append to a list is
to perform a push operation.
.. versionadded:: 0.4
.. versionchanged:: 0.6 - added reverse keyword
"""
_ordering = None
_order_reverse = False
def __init__(self, field, **kwargs):
if 'ordering' in kwargs.keys():
self._ordering = kwargs.pop('ordering')
if 'reverse' in kwargs.keys():
self._order_reverse = kwargs.pop('reverse')
super(SortedListField, self).__init__(field, **kwargs)
def to_mongo(self, value, use_db_field=True, fields=None):
value = super(SortedListField, self).to_mongo(value, use_db_field, fields)
if self._ordering is not None:
return sorted(value, key=itemgetter(self._ordering),
reverse=self._order_reverse)
return sorted(value, reverse=self._order_reverse)
def key_not_string(d):
"""Helper function to recursively determine if any key in a
dictionary is not a string.
"""
for k, v in d.items():
if not isinstance(k, six.string_types) or (isinstance(v, dict) and key_not_string(v)):
return True
def key_has_dot_or_dollar(d):
"""Helper function to recursively determine if any key in a
dictionary contains a dot or a dollar sign.
"""
for k, v in d.items():
if ('.' in k or '$' in k) or (isinstance(v, dict) and key_has_dot_or_dollar(v)):
return True
class DictField(ComplexBaseField):
"""A dictionary field that wraps a standard Python dictionary. This is
similar to an embedded document, but the structure is not defined.
.. note::
Required means it cannot be empty - as the default for DictFields is {}
.. versionadded:: 0.3
.. versionchanged:: 0.5 - Can now handle complex / varying types of data
"""
def __init__(self, basecls=None, field=None, *args, **kwargs):
self.field = field
self._auto_dereference = False
self.basecls = basecls or BaseField
if not issubclass(self.basecls, BaseField):
self.error('DictField only accepts dict values')
kwargs.setdefault('default', lambda: {})
super(DictField, self).__init__(*args, **kwargs)
def validate(self, value):
"""Make sure that a list of valid fields is being used."""
if not isinstance(value, dict):
self.error('Only dictionaries may be used in a DictField')
if key_not_string(value):
msg = ('Invalid dictionary key - documents must '
'have only string keys')
self.error(msg)
if key_has_dot_or_dollar(value):
self.error('Invalid dictionary key name - keys may not contain "."'
' or "$" characters')
super(DictField, self).validate(value)
def lookup_member(self, member_name):
return DictField(basecls=self.basecls, db_field=member_name)
def prepare_query_value(self, op, value):
match_operators = ['contains', 'icontains', 'startswith',
'istartswith', 'endswith', 'iendswith',
'exact', 'iexact']
if op in match_operators and isinstance(value, six.string_types):
return StringField().prepare_query_value(op, value)
if hasattr(self.field, 'field'):
if op in ('set', 'unset') and isinstance(value, dict):
return {
k: self.field.prepare_query_value(op, v)
for k, v in value.items()
}
return self.field.prepare_query_value(op, value)
return super(DictField, self).prepare_query_value(op, value)
class MapField(DictField):
"""A field that maps a name to a specified field type. Similar to
a DictField, except the 'value' of each item must match the specified
field type.
.. versionadded:: 0.5
"""
def __init__(self, field=None, *args, **kwargs):
if not isinstance(field, BaseField):
self.error('Argument to MapField constructor must be a valid '
'field')
super(MapField, self).__init__(field=field, *args, **kwargs)
class ReferenceField(BaseField):
"""A reference to a document that will be automatically dereferenced on
access (lazily).
Use the `reverse_delete_rule` to handle what should happen if the document
the field is referencing is deleted. EmbeddedDocuments, DictFields and
MapFields does not support reverse_delete_rule and an `InvalidDocumentError`
will be raised if trying to set on one of these Document / Field types.
The options are:
* DO_NOTHING (0) - don't do anything (default).
* NULLIFY (1) - Updates the reference to null.
* CASCADE (2) - Deletes the documents associated with the reference.
* DENY (3) - Prevent the deletion of the reference object.
* PULL (4) - Pull the reference from a :class:`~mongoengine.fields.ListField` of references
Alternative syntax for registering delete rules (useful when implementing
bi-directional delete rules)
.. code-block:: python
class Bar(Document):
content = StringField()
foo = ReferenceField('Foo')
Foo.register_delete_rule(Bar, 'foo', NULLIFY)
.. versionchanged:: 0.5 added `reverse_delete_rule`
"""
def __init__(self, document_type, dbref=False,
reverse_delete_rule=DO_NOTHING, **kwargs):
"""Initialises the Reference Field.
:param dbref: Store the reference as :class:`~pymongo.dbref.DBRef`
or as the :class:`~pymongo.objectid.ObjectId`.id .
:param reverse_delete_rule: Determines what to do when the referring
object is deleted
.. note ::
A reference to an abstract document type is always stored as a
:class:`~pymongo.dbref.DBRef`, regardless of the value of `dbref`.
"""
if (
not isinstance(document_type, six.string_types) and
not issubclass(document_type, Document)
):
self.error('Argument to ReferenceField constructor must be a '
'document class or a string')
self.dbref = dbref
self.document_type_obj = document_type
self.reverse_delete_rule = reverse_delete_rule
super(ReferenceField, self).__init__(**kwargs)
@property
def document_type(self):
if isinstance(self.document_type_obj, six.string_types):
if self.document_type_obj == RECURSIVE_REFERENCE_CONSTANT:
self.document_type_obj = self.owner_document
else:
self.document_type_obj = get_document(self.document_type_obj)
return self.document_type_obj
def __get__(self, instance, owner):
"""Descriptor to allow lazy dereferencing."""
if instance is None:
# Document class being used rather than a document object
return self
# Get value from document instance if available
value = instance._data.get(self.name)
self._auto_dereference = instance._fields[self.name]._auto_dereference
# Dereference DBRefs
if self._auto_dereference and isinstance(value, DBRef):
if hasattr(value, 'cls'):
# Dereference using the class type specified in the reference
cls = get_document(value.cls)
else:
cls = self.document_type
dereferenced = cls._get_db().dereference(value)
if dereferenced is None:
raise DoesNotExist('Trying to dereference unknown document %s' % value)
else:
instance._data[self.name] = cls._from_son(dereferenced)
return super(ReferenceField, self).__get__(instance, owner)
def to_mongo(self, document):
if isinstance(document, DBRef):
if not self.dbref:
return document.id
return document
if isinstance(document, Document):
# We need the id from the saved object to create the DBRef
id_ = document.pk
if id_ is None:
self.error('You can only reference documents once they have'
' been saved to the database')
# Use the attributes from the document instance, so that they
# override the attributes of this field's document type
cls = document
else:
id_ = document
cls = self.document_type
id_field_name = cls._meta['id_field']
id_field = cls._fields[id_field_name]
id_ = id_field.to_mongo(id_)
if self.document_type._meta.get('abstract'):
collection = cls._get_collection_name()
return DBRef(collection, id_, cls=cls._class_name)
elif self.dbref:
collection = cls._get_collection_name()
return DBRef(collection, id_)
return id_
def to_python(self, value):
"""Convert a MongoDB-compatible type to a Python type."""
if (not self.dbref and
not isinstance(value, (DBRef, Document, EmbeddedDocument))):
collection = self.document_type._get_collection_name()
value = DBRef(collection, self.document_type.id.to_python(value))
return value
def prepare_query_value(self, op, value):
if value is None:
return None
super(ReferenceField, self).prepare_query_value(op, value)
return self.to_mongo(value)
def validate(self, value):
if not isinstance(value, (self.document_type, DBRef, ObjectId)):
self.error('A ReferenceField only accepts DBRef, ObjectId or documents')
if isinstance(value, Document) and value.id is None:
self.error('You can only reference documents once they have been '
'saved to the database')
if self.document_type._meta.get('abstract') and \
not isinstance(value, self.document_type):
self.error(
'%s is not an instance of abstract reference type %s' % (
self.document_type._class_name)
)
def lookup_member(self, member_name):
return self.document_type._fields.get(member_name)
class CachedReferenceField(BaseField):
"""
A referencefield with cache fields to purpose pseudo-joins
.. versionadded:: 0.9
"""
def __init__(self, document_type, fields=None, auto_sync=True, **kwargs):
"""Initialises the Cached Reference Field.
:param fields: A list of fields to be cached in document
:param auto_sync: if True documents are auto updated.
"""
if fields is None:
fields = []
if (
not isinstance(document_type, six.string_types) and
not issubclass(document_type, Document)
):
self.error('Argument to CachedReferenceField constructor must be a'
' document class or a string')
self.auto_sync = auto_sync
self.document_type_obj = document_type
self.fields = fields
super(CachedReferenceField, self).__init__(**kwargs)
def start_listener(self):
from mongoengine import signals
signals.post_save.connect(self.on_document_pre_save,
sender=self.document_type)
def on_document_pre_save(self, sender, document, created, **kwargs):
if created:
return None
update_kwargs = {
'set__%s__%s' % (self.name, key): val
for key, val in document._delta()[0].items()
if key in self.fields
}
if update_kwargs:
filter_kwargs = {}
filter_kwargs[self.name] = document
self.owner_document.objects(
**filter_kwargs).update(**update_kwargs)
def to_python(self, value):
if isinstance(value, dict):
collection = self.document_type._get_collection_name()
value = DBRef(
collection, self.document_type.id.to_python(value['_id']))
return self.document_type._from_son(self.document_type._get_db().dereference(value))
return value
@property
def document_type(self):
if isinstance(self.document_type_obj, six.string_types):
if self.document_type_obj == RECURSIVE_REFERENCE_CONSTANT:
self.document_type_obj = self.owner_document
else:
self.document_type_obj = get_document(self.document_type_obj)
return self.document_type_obj
def __get__(self, instance, owner):
if instance is None:
# Document class being used rather than a document object
return self
# Get value from document instance if available
value = instance._data.get(self.name)
self._auto_dereference = instance._fields[self.name]._auto_dereference
# Dereference DBRefs
if self._auto_dereference and isinstance(value, DBRef):
dereferenced = self.document_type._get_db().dereference(value)
if dereferenced is None:
raise DoesNotExist('Trying to dereference unknown document %s' % value)
else:
instance._data[self.name] = self.document_type._from_son(dereferenced)
return super(CachedReferenceField, self).__get__(instance, owner)
def to_mongo(self, document, use_db_field=True, fields=None):
id_field_name = self.document_type._meta['id_field']
id_field = self.document_type._fields[id_field_name]
if isinstance(document, Document):
# We need the id from the saved object to create the DBRef
id_ = document.pk
if id_ is None:
self.error('You can only reference documents once they have'
' been saved to the database')
else:
self.error('Only accept a document object')
# TODO: should raise here or will fail next statement
value = SON((
('_id', id_field.to_mongo(id_)),
))
if fields:
new_fields = [f for f in self.fields if f in fields]
else:
new_fields = self.fields
value.update(dict(document.to_mongo(use_db_field, fields=new_fields)))
return value
def prepare_query_value(self, op, value):
if value is None:
return None
if isinstance(value, Document):
if value.pk is None:
self.error('You can only reference documents once they have'
' been saved to the database')
return {'_id': value.pk}
raise NotImplementedError
def validate(self, value):
if not isinstance(value, self.document_type):
self.error('A CachedReferenceField only accepts documents')
if isinstance(value, Document) and value.id is None:
self.error('You can only reference documents once they have been '
'saved to the database')
def lookup_member(self, member_name):
return self.document_type._fields.get(member_name)
def sync_all(self):
"""
Sync all cached fields on demand.
Caution: this operation may be slower.
"""
update_key = 'set__%s' % self.name
for doc in self.document_type.objects:
filter_kwargs = {}
filter_kwargs[self.name] = doc
update_kwargs = {}
update_kwargs[update_key] = doc
self.owner_document.objects(
**filter_kwargs).update(**update_kwargs)
class GenericReferenceField(BaseField):
"""A reference to *any* :class:`~mongoengine.document.Document` subclass
that will be automatically dereferenced on access (lazily).
.. note ::
* Any documents used as a generic reference must be registered in the
document registry. Importing the model will automatically register
it.
* You can use the choices param to limit the acceptable Document types
.. versionadded:: 0.3
"""
def __init__(self, *args, **kwargs):
choices = kwargs.pop('choices', None)
super(GenericReferenceField, self).__init__(*args, **kwargs)
self.choices = []
# Keep the choices as a list of allowed Document class names
if choices:
for choice in choices:
if isinstance(choice, six.string_types):
self.choices.append(choice)
elif isinstance(choice, type) and issubclass(choice, Document):
self.choices.append(choice._class_name)
else:
self.error('Invalid choices provided: must be a list of'
'Document subclasses and/or six.string_typess')
def _validate_choices(self, value):
if isinstance(value, dict):
# If the field has not been dereferenced, it is still a dict
# of class and DBRef
value = value.get('_cls')
elif isinstance(value, Document):
value = value._class_name
super(GenericReferenceField, self)._validate_choices(value)
def __get__(self, instance, owner):
if instance is None:
return self
value = instance._data.get(self.name)
self._auto_dereference = instance._fields[self.name]._auto_dereference
if self._auto_dereference and isinstance(value, (dict, SON)):
dereferenced = self.dereference(value)
if dereferenced is None:
raise DoesNotExist('Trying to dereference unknown document %s' % value)
else:
instance._data[self.name] = dereferenced
return super(GenericReferenceField, self).__get__(instance, owner)
def validate(self, value):
if not isinstance(value, (Document, DBRef, dict, SON)):
self.error('GenericReferences can only contain documents')
if isinstance(value, (dict, SON)):
if '_ref' not in value or '_cls' not in value:
self.error('GenericReferences can only contain documents')
# We need the id from the saved object to create the DBRef
elif isinstance(value, Document) and value.id is None:
self.error('You can only reference documents once they have been'
' saved to the database')
def dereference(self, value):
doc_cls = get_document(value['_cls'])
reference = value['_ref']
doc = doc_cls._get_db().dereference(reference)
if doc is not None:
doc = doc_cls._from_son(doc)
return doc
def to_mongo(self, document):
if document is None:
return None
if isinstance(document, (dict, SON, ObjectId, DBRef)):
return document
id_field_name = document.__class__._meta['id_field']
id_field = document.__class__._fields[id_field_name]
if isinstance(document, Document):
# We need the id from the saved object to create the DBRef
id_ = document.id
if id_ is None:
self.error('You can only reference documents once they have'
' been saved to the database')
else:
id_ = document
id_ = id_field.to_mongo(id_)
collection = document._get_collection_name()
ref = DBRef(collection, id_)
return SON((
('_cls', document._class_name),
('_ref', ref)
))
def prepare_query_value(self, op, value):
if value is None:
return None
return self.to_mongo(value)
class BinaryField(BaseField):
"""A binary data field."""
def __init__(self, max_bytes=None, **kwargs):
self.max_bytes = max_bytes
super(BinaryField, self).__init__(**kwargs)
def __set__(self, instance, value):
"""Handle bytearrays in python 3.1"""
if six.PY3 and isinstance(value, bytearray):
value = six.binary_type(value)
return super(BinaryField, self).__set__(instance, value)
def to_mongo(self, value):
return Binary(value)
def validate(self, value):
if not isinstance(value, (six.binary_type, six.text_type, Binary)):
self.error('BinaryField only accepts instances of '
'(%s, %s, Binary)' % (
six.binary_type.__name__, six.text_type.__name__))
if self.max_bytes is not None and len(value) > self.max_bytes:
self.error('Binary value is too long')
class GridFSError(Exception):
pass
class GridFSProxy(object):
"""Proxy object to handle writing and reading of files to and from GridFS
.. versionadded:: 0.4
.. versionchanged:: 0.5 - added optional size param to read
.. versionchanged:: 0.6 - added collection name param
"""
_fs = None
def __init__(self, grid_id=None, key=None,
instance=None,
db_alias=DEFAULT_CONNECTION_NAME,
collection_name='fs'):
self.grid_id = grid_id # Store GridFS id for file
self.key = key
self.instance = instance
self.db_alias = db_alias
self.collection_name = collection_name
self.newfile = None # Used for partial writes
self.gridout = None
def __getattr__(self, name):
attrs = ('_fs', 'grid_id', 'key', 'instance', 'db_alias',
'collection_name', 'newfile', 'gridout')
if name in attrs:
return self.__getattribute__(name)
obj = self.get()
if hasattr(obj, name):
return getattr(obj, name)
raise AttributeError
def __get__(self, instance, value):
return self
def __nonzero__(self):
return bool(self.grid_id)
def __getstate__(self):
self_dict = self.__dict__
self_dict['_fs'] = None
return self_dict
def __copy__(self):
copied = GridFSProxy()
copied.__dict__.update(self.__getstate__())
return copied
def __deepcopy__(self, memo):
return self.__copy__()
def __repr__(self):
return '<%s: %s>' % (self.__class__.__name__, self.grid_id)
def __str__(self):
name = getattr(
self.get(), 'filename', self.grid_id) if self.get() else '(no file)'
return '<%s: %s>' % (self.__class__.__name__, name)
def __eq__(self, other):
if isinstance(other, GridFSProxy):
return ((self.grid_id == other.grid_id) and
(self.collection_name == other.collection_name) and
(self.db_alias == other.db_alias))
else:
return False
@property
def fs(self):
if not self._fs:
self._fs = gridfs.GridFS(
get_db(self.db_alias), self.collection_name)
return self._fs
def get(self, grid_id=None):
if grid_id:
self.grid_id = grid_id
if self.grid_id is None:
return None
try:
if self.gridout is None:
self.gridout = self.fs.get(self.grid_id)
return self.gridout
except Exception:
# File has been deleted
return None
def new_file(self, **kwargs):
self.newfile = self.fs.new_file(**kwargs)
self.grid_id = self.newfile._id
self._mark_as_changed()
def put(self, file_obj, **kwargs):
if self.grid_id:
raise GridFSError('This document already has a file. Either delete '
'it or call replace to overwrite it')
self.grid_id = self.fs.put(file_obj, **kwargs)
self._mark_as_changed()
def write(self, string):
if self.grid_id:
if not self.newfile:
raise GridFSError('This document already has a file. Either '
'delete it or call replace to overwrite it')
else:
self.new_file()
self.newfile.write(string)
def writelines(self, lines):
if not self.newfile:
self.new_file()
self.grid_id = self.newfile._id
self.newfile.writelines(lines)
def read(self, size=-1):
gridout = self.get()
if gridout is None:
return None
else:
try:
return gridout.read(size)
except Exception:
return ''
def delete(self):
# Delete file from GridFS, FileField still remains
self.fs.delete(self.grid_id)
self.grid_id = None
self.gridout = None
self._mark_as_changed()
def replace(self, file_obj, **kwargs):
self.delete()
self.put(file_obj, **kwargs)
def close(self):
if self.newfile:
self.newfile.close()
def _mark_as_changed(self):
"""Inform the instance that `self.key` has been changed"""
if self.instance:
self.instance._mark_as_changed(self.key)
class FileField(BaseField):
"""A GridFS storage field.
.. versionadded:: 0.4
.. versionchanged:: 0.5 added optional size param for read
.. versionchanged:: 0.6 added db_alias for multidb support
"""
proxy_class = GridFSProxy
def __init__(self, db_alias=DEFAULT_CONNECTION_NAME, collection_name='fs',
**kwargs):
super(FileField, self).__init__(**kwargs)
self.collection_name = collection_name
self.db_alias = db_alias
def __get__(self, instance, owner):
if instance is None:
return self
# Check if a file already exists for this model
grid_file = instance._data.get(self.name)
if not isinstance(grid_file, self.proxy_class):
grid_file = self.get_proxy_obj(key=self.name, instance=instance)
instance._data[self.name] = grid_file
if not grid_file.key:
grid_file.key = self.name
grid_file.instance = instance
return grid_file
def __set__(self, instance, value):
key = self.name
if (
(hasattr(value, 'read') and not isinstance(value, GridFSProxy)) or
isinstance(value, (six.binary_type, six.string_types))
):
# using "FileField() = file/string" notation
grid_file = instance._data.get(self.name)
# If a file already exists, delete it
if grid_file:
try:
grid_file.delete()
except Exception:
pass
# Create a new proxy object as we don't already have one
instance._data[key] = self.get_proxy_obj(
key=key, instance=instance)
instance._data[key].put(value)
else:
instance._data[key] = value
instance._mark_as_changed(key)
def get_proxy_obj(self, key, instance, db_alias=None, collection_name=None):
if db_alias is None:
db_alias = self.db_alias
if collection_name is None:
collection_name = self.collection_name
return self.proxy_class(key=key, instance=instance,
db_alias=db_alias,
collection_name=collection_name)
def to_mongo(self, value):
# Store the GridFS file id in MongoDB
if isinstance(value, self.proxy_class) and value.grid_id is not None:
return value.grid_id
return None
def to_python(self, value):
if value is not None:
return self.proxy_class(value,
collection_name=self.collection_name,
db_alias=self.db_alias)
def validate(self, value):
if value.grid_id is not None:
if not isinstance(value, self.proxy_class):
self.error('FileField only accepts GridFSProxy values')
if not isinstance(value.grid_id, ObjectId):
self.error('Invalid GridFSProxy value')
class ImageGridFsProxy(GridFSProxy):
"""
Proxy for ImageField
versionadded: 0.6
"""
def put(self, file_obj, **kwargs):
"""
Insert a image in database
applying field properties (size, thumbnail_size)
"""
field = self.instance._fields[self.key]
# Handle nested fields
if hasattr(field, 'field') and isinstance(field.field, FileField):
field = field.field
try:
img = Image.open(file_obj)
img_format = img.format
except Exception as e:
raise ValidationError('Invalid image: %s' % e)
# Progressive JPEG
# TODO: fixme, at least unused, at worst bad implementation
progressive = img.info.get('progressive') or False
if (kwargs.get('progressive') and
isinstance(kwargs.get('progressive'), bool) and
img_format == 'JPEG'):
progressive = True
else:
progressive = False
if (field.size and (img.size[0] > field.size['width'] or
img.size[1] > field.size['height'])):
size = field.size
if size['force']:
img = ImageOps.fit(img,
(size['width'],
size['height']),
Image.ANTIALIAS)
else:
img.thumbnail((size['width'],
size['height']),
Image.ANTIALIAS)
thumbnail = None
if field.thumbnail_size:
size = field.thumbnail_size
if size['force']:
thumbnail = ImageOps.fit(
img, (size['width'], size['height']), Image.ANTIALIAS)
else:
thumbnail = img.copy()
thumbnail.thumbnail((size['width'],
size['height']),
Image.ANTIALIAS)
if thumbnail:
thumb_id = self._put_thumbnail(thumbnail, img_format, progressive)
else:
thumb_id = None
w, h = img.size
io = StringIO()
img.save(io, img_format, progressive=progressive)
io.seek(0)
return super(ImageGridFsProxy, self).put(io,
width=w,
height=h,
format=img_format,
thumbnail_id=thumb_id,
**kwargs)
def delete(self, *args, **kwargs):
# deletes thumbnail
out = self.get()
if out and out.thumbnail_id:
self.fs.delete(out.thumbnail_id)
return super(ImageGridFsProxy, self).delete()
def _put_thumbnail(self, thumbnail, format, progressive, **kwargs):
w, h = thumbnail.size
io = StringIO()
thumbnail.save(io, format, progressive=progressive)
io.seek(0)
return self.fs.put(io, width=w,
height=h,
format=format,
**kwargs)
@property
def size(self):
"""
return a width, height of image
"""
out = self.get()
if out:
return out.width, out.height
@property
def format(self):
"""
return format of image
ex: PNG, JPEG, GIF, etc
"""
out = self.get()
if out:
return out.format
@property
def thumbnail(self):
"""
return a gridfs.grid_file.GridOut
representing a thumbnail of Image
"""
out = self.get()
if out and out.thumbnail_id:
return self.fs.get(out.thumbnail_id)
def write(self, *args, **kwargs):
raise RuntimeError('Please use "put" method instead')
def writelines(self, *args, **kwargs):
raise RuntimeError('Please use "put" method instead')
class ImproperlyConfigured(Exception):
pass
class ImageField(FileField):
"""
A Image File storage field.
@size (width, height, force):
max size to store images, if larger will be automatically resized
ex: size=(800, 600, True)
@thumbnail (width, height, force):
size to generate a thumbnail
.. versionadded:: 0.6
"""
proxy_class = ImageGridFsProxy
def __init__(self, size=None, thumbnail_size=None,
collection_name='images', **kwargs):
if not Image:
raise ImproperlyConfigured('PIL library was not found')
params_size = ('width', 'height', 'force')
extra_args = {
'size': size,
'thumbnail_size': thumbnail_size
}
for att_name, att in extra_args.items():
value = None
if isinstance(att, (tuple, list)):
if six.PY3:
value = dict(itertools.zip_longest(params_size, att,
fillvalue=None))
else:
value = dict(map(None, params_size, att))
setattr(self, att_name, value)
super(ImageField, self).__init__(
collection_name=collection_name,
**kwargs)
class SequenceField(BaseField):
"""Provides a sequential counter see:
http://www.mongodb.org/display/DOCS/Object+IDs#ObjectIDs-SequenceNumbers
.. note::
Although traditional databases often use increasing sequence
numbers for primary keys. In MongoDB, the preferred approach is to
use Object IDs instead. The concept is that in a very large
cluster of machines, it is easier to create an object ID than have
global, uniformly increasing sequence numbers.
:param collection_name: Name of the counter collection (default 'mongoengine.counters')
:param sequence_name: Name of the sequence in the collection (default 'ClassName.counter')
:param value_decorator: Any callable to use as a counter (default int)
Use any callable as `value_decorator` to transform calculated counter into
any value suitable for your needs, e.g. string or hexadecimal
representation of the default integer counter value.
.. note::
In case the counter is defined in the abstract document, it will be
common to all inherited documents and the default sequence name will
be the class name of the abstract document.
.. versionadded:: 0.5
.. versionchanged:: 0.8 added `value_decorator`
"""
_auto_gen = True
COLLECTION_NAME = 'mongoengine.counters'
VALUE_DECORATOR = int
def __init__(self, collection_name=None, db_alias=None, sequence_name=None,
value_decorator=None, *args, **kwargs):
self.collection_name = collection_name or self.COLLECTION_NAME
self.db_alias = db_alias or DEFAULT_CONNECTION_NAME
self.sequence_name = sequence_name
self.value_decorator = (callable(value_decorator) and
value_decorator or self.VALUE_DECORATOR)
super(SequenceField, self).__init__(*args, **kwargs)
def generate(self):
"""
Generate and Increment the counter
"""
sequence_name = self.get_sequence_name()
sequence_id = '%s.%s' % (sequence_name, self.name)
collection = get_db(alias=self.db_alias)[self.collection_name]
counter = collection.find_and_modify(query={'_id': sequence_id},
update={'$inc': {'next': 1}},
new=True,
upsert=True)
return self.value_decorator(counter['next'])
def set_next_value(self, value):
"""Helper method to set the next sequence value"""
sequence_name = self.get_sequence_name()
sequence_id = "%s.%s" % (sequence_name, self.name)
collection = get_db(alias=self.db_alias)[self.collection_name]
counter = collection.find_and_modify(query={"_id": sequence_id},
update={"$set": {"next": value}},
new=True,
upsert=True)
return self.value_decorator(counter['next'])
def get_next_value(self):
"""Helper method to get the next value for previewing.
.. warning:: There is no guarantee this will be the next value
as it is only fixed on set.
"""
sequence_name = self.get_sequence_name()
sequence_id = '%s.%s' % (sequence_name, self.name)
collection = get_db(alias=self.db_alias)[self.collection_name]
data = collection.find_one({'_id': sequence_id})
if data:
return self.value_decorator(data['next'] + 1)
return self.value_decorator(1)
def get_sequence_name(self):
if self.sequence_name:
return self.sequence_name
owner = self.owner_document
if issubclass(owner, Document) and not owner._meta.get('abstract'):
return owner._get_collection_name()
else:
return ''.join('_%s' % c if c.isupper() else c
for c in owner._class_name).strip('_').lower()
def __get__(self, instance, owner):
value = super(SequenceField, self).__get__(instance, owner)
if value is None and instance._initialised:
value = self.generate()
instance._data[self.name] = value
instance._mark_as_changed(self.name)
return value
def __set__(self, instance, value):
if value is None and instance._initialised:
value = self.generate()
return super(SequenceField, self).__set__(instance, value)
def prepare_query_value(self, op, value):
"""
This method is overridden in order to convert the query value into to required
type. We need to do this in order to be able to successfully compare query
values passed as string, the base implementation returns the value as is.
"""
return self.value_decorator(value)
def to_python(self, value):
if value is None:
value = self.generate()
return value
class UUIDField(BaseField):
"""A UUID field.
.. versionadded:: 0.6
"""
_binary = None
def __init__(self, binary=True, **kwargs):
"""
Store UUID data in the database
:param binary: if False store as a string.
.. versionchanged:: 0.8.0
.. versionchanged:: 0.6.19
"""
self._binary = binary
super(UUIDField, self).__init__(**kwargs)
def to_python(self, value):
if not self._binary:
original_value = value
try:
if not isinstance(value, six.string_types):
value = six.text_type(value)
return uuid.UUID(value)
except Exception:
return original_value
return value
def to_mongo(self, value):
if not self._binary:
return six.text_type(value)
elif isinstance(value, six.string_types):
return uuid.UUID(value)
return value
def prepare_query_value(self, op, value):
if value is None:
return None
return self.to_mongo(value)
def validate(self, value):
if not isinstance(value, uuid.UUID):
if not isinstance(value, six.string_types):
value = str(value)
try:
uuid.UUID(value)
except Exception as exc:
self.error('Could not convert to UUID: %s' % exc)
class GeoPointField(BaseField):
"""A list storing a longitude and latitude coordinate.
.. note:: this represents a generic point in a 2D plane and a legacy way of
representing a geo point. It admits 2d indexes but not "2dsphere" indexes
in MongoDB > 2.4 which are more natural for modeling geospatial points.
See :ref:`geospatial-indexes`
.. versionadded:: 0.4
"""
_geo_index = pymongo.GEO2D
def validate(self, value):
"""Make sure that a geo-value is of type (x, y)"""
if not isinstance(value, (list, tuple)):
self.error('GeoPointField can only accept tuples or lists '
'of (x, y)')
if not len(value) == 2:
self.error('Value (%s) must be a two-dimensional point' %
repr(value))
elif (not isinstance(value[0], (float, int)) or
not isinstance(value[1], (float, int))):
self.error(
'Both values (%s) in point must be float or int' % repr(value))
class PointField(GeoJsonBaseField):
"""A GeoJSON field storing a longitude and latitude coordinate.
The data is represented as:
.. code-block:: js
{'type' : 'Point' ,
'coordinates' : [x, y]}
You can either pass a dict with the full information or a list
to set the value.
Requires mongodb >= 2.4
.. versionadded:: 0.8
"""
_type = 'Point'
class LineStringField(GeoJsonBaseField):
"""A GeoJSON field storing a line of longitude and latitude coordinates.
The data is represented as:
.. code-block:: js
{'type' : 'LineString' ,
'coordinates' : [[x1, y1], [x1, y1] ... [xn, yn]]}
You can either pass a dict with the full information or a list of points.
Requires mongodb >= 2.4
.. versionadded:: 0.8
"""
_type = 'LineString'
class PolygonField(GeoJsonBaseField):
"""A GeoJSON field storing a polygon of longitude and latitude coordinates.
The data is represented as:
.. code-block:: js
{'type' : 'Polygon' ,
'coordinates' : [[[x1, y1], [x1, y1] ... [xn, yn]],
[[x1, y1], [x1, y1] ... [xn, yn]]}
You can either pass a dict with the full information or a list
of LineStrings. The first LineString being the outside and the rest being
holes.
Requires mongodb >= 2.4
.. versionadded:: 0.8
"""
_type = 'Polygon'
class MultiPointField(GeoJsonBaseField):
"""A GeoJSON field storing a list of Points.
The data is represented as:
.. code-block:: js
{'type' : 'MultiPoint' ,
'coordinates' : [[x1, y1], [x2, y2]]}
You can either pass a dict with the full information or a list
to set the value.
Requires mongodb >= 2.6
.. versionadded:: 0.9
"""
_type = 'MultiPoint'
class MultiLineStringField(GeoJsonBaseField):
"""A GeoJSON field storing a list of LineStrings.
The data is represented as:
.. code-block:: js
{'type' : 'MultiLineString' ,
'coordinates' : [[[x1, y1], [x1, y1] ... [xn, yn]],
[[x1, y1], [x1, y1] ... [xn, yn]]]}
You can either pass a dict with the full information or a list of points.
Requires mongodb >= 2.6
.. versionadded:: 0.9
"""
_type = 'MultiLineString'
class MultiPolygonField(GeoJsonBaseField):
"""A GeoJSON field storing list of Polygons.
The data is represented as:
.. code-block:: js
{'type' : 'MultiPolygon' ,
'coordinates' : [[
[[x1, y1], [x1, y1] ... [xn, yn]],
[[x1, y1], [x1, y1] ... [xn, yn]]
], [
[[x1, y1], [x1, y1] ... [xn, yn]],
[[x1, y1], [x1, y1] ... [xn, yn]]
]
}
You can either pass a dict with the full information or a list
of Polygons.
Requires mongodb >= 2.6
.. versionadded:: 0.9
"""
_type = 'MultiPolygon'