import base64 from collections import OrderedDict import logging from .properties import InvalidField from .util import create_element, xml_to_str, value_to_xml_text, is_iterable from .version import EXCHANGE_2010 log = logging.getLogger(__name__) class Q: """A class with an API similar to Django Q objects. Used to implemnt advanced filtering logic.""" # Connection types AND = 'AND' OR = 'OR' NOT = 'NOT' CONN_TYPES = {AND, OR, NOT} # EWS Operators EQ = '==' NE = '!=' GT = '>' GTE = '>=' LT = '<' LTE = '<=' EXACT = 'exact' IEXACT = 'iexact' CONTAINS = 'contains' ICONTAINS = 'icontains' STARTSWITH = 'startswith' ISTARTSWITH = 'istartswith' EXISTS = 'exists' OP_TYPES = {EQ, NE, GT, GTE, LT, LTE, EXACT, IEXACT, CONTAINS, ICONTAINS, STARTSWITH, ISTARTSWITH, EXISTS} CONTAINS_OPS = {EXACT, IEXACT, CONTAINS, ICONTAINS, STARTSWITH, ISTARTSWITH} # Valid lookups LOOKUP_RANGE = 'range' LOOKUP_IN = 'in' LOOKUP_NOT = 'not' LOOKUP_GT = 'gt' LOOKUP_GTE = 'gte' LOOKUP_LT = 'lt' LOOKUP_LTE = 'lte' LOOKUP_EXACT = 'exact' LOOKUP_IEXACT = 'iexact' LOOKUP_CONTAINS = 'contains' LOOKUP_ICONTAINS = 'icontains' LOOKUP_STARTSWITH = 'startswith' LOOKUP_ISTARTSWITH = 'istartswith' LOOKUP_EXISTS = 'exists' LOOKUP_TYPES = {LOOKUP_RANGE, LOOKUP_IN, LOOKUP_NOT, LOOKUP_GT, LOOKUP_GTE, LOOKUP_LT, LOOKUP_LTE, LOOKUP_EXACT, LOOKUP_IEXACT, LOOKUP_CONTAINS, LOOKUP_ICONTAINS, LOOKUP_STARTSWITH, LOOKUP_ISTARTSWITH, LOOKUP_EXISTS} __slots__ = ('conn_type', 'field_path', 'op', 'value', 'children', 'query_string') def __init__(self, *args, **kwargs): self.conn_type = kwargs.pop('conn_type', self.AND) self.field_path = None # Name of the field we want to filter on self.op = None self.value = None self.query_string = None # Parsing of args and kwargs may require child elements self.children = [] # Remove any empty Q elements in args before proceeding args = tuple(a for a in args if not (isinstance(a, self.__class__) and a.is_empty())) # Check for query string, or Q object containing query string, as the only argument if len(args) == 1 and not kwargs: if isinstance(args[0], str): self.query_string = args[0] return if isinstance(args[0], self.__class__) and args[0].query_string: self.query_string = args[0].query_string return # Parse args which must be Q objects for q in args: if not isinstance(q, self.__class__): raise ValueError("Non-keyword arg %r must be a Q instance" % q) if q.query_string: raise ValueError( 'A query string cannot be combined with other restrictions (args: %r, kwargs: %r)' % (args, kwargs) ) self.children.append(q) # Parse keyword args and extract the filter is_single_kwarg = len(args) == 0 and len(kwargs) == 1 for key, value in kwargs.items(): children = self._get_children_from_kwarg(key=key, value=value, is_single_kwarg=is_single_kwarg) self.children.extend(children) if len(self.children) == 1 and self.field_path is None and self.conn_type != self.NOT: # We only have one child and no expression on ourselves, so we are a no-op. Flatten by taking over the child self._promote() def _get_children_from_kwarg(self, key, value, is_single_kwarg=False): # Generates Q objects corresponding to a single keyword argument. Makes this a leaf if there are no children to # generate. key_parts = key.rsplit('__', 1) if len(key_parts) == 2 and key_parts[1] in self.LOOKUP_TYPES: # This is a kwarg with a lookup at the end field_path, lookup = key_parts if lookup == self.LOOKUP_EXISTS: # value=True will fall through to further processing if not value: return [~self.__class__(**{key: True})] if lookup == self.LOOKUP_RANGE: # EWS doesn't have a 'range' operator. Emulate 'foo__range=(1, 2)' as 'foo__gte=1 and foo__lte=2' # (both values inclusive). if len(value) != 2: raise ValueError("Value of lookup '%s' must have exactly 2 elements" % key) return [ self.__class__(**{'%s__gte' % field_path: value[0]}), self.__class__(**{'%s__lte' % field_path: value[1]}), ] if lookup == self.LOOKUP_IN: # EWS doesn't have an '__in' operator. Allow '__in' lookups on list and non-list field types, # specifying a list value. We'll emulate it as a set of OR'ed exact matches. if not is_iterable(value, generators_allowed=True): raise ValueError("Value for lookup %r must be a list" % key) children = [self.__class__(**{field_path: v}) for v in value] return [self.__class__(*children, conn_type=self.OR)] # Filtering on list types is a bit quirky. The only lookup type I have found to work is: # # item:Categories == 'foo' AND item:Categories == 'bar' AND ... # # item:Categories == 'foo' OR item:Categories == 'bar' OR ... # # The former returns items that have all these categories, but maybe also others. The latter returns # items that have at least one of these categories. This translates to the 'contains' and 'in' lookups. # Both versions are case-insensitive. # # Exact matching and case-sensitive or partial-string matching is not possible since that requires the # 'Contains' element which only supports matching on string elements, not arrays. # # Exact matching of categories (i.e. match ['a', 'b'] but not ['a', 'b', 'c']) could be implemented by # post-processing items by fetch the categories field unconditionally and removing the items that don't # have an exact match. if lookup == self.LOOKUP_CONTAINS and is_iterable(value, generators_allowed=True): # '__contains' lookups on list field types children = [self.__class__(**{field_path: v}) for v in value] return [self.__class__(*children, conn_type=self.AND)] try: op = self._lookup_to_op(lookup) except KeyError: raise ValueError("Lookup '%s' is not supported (called as '%s=%r')" % (lookup, key, value)) else: field_path, op = key, self.EQ if not is_single_kwarg: return [self.__class__(**{key: value})] # This is a single-kwarg Q object with a lookup that requires a single value. Make this a leaf self.field_path = field_path self.op = op self.value = value return [] def _promote(self): # Flatten by taking over the only child if len(self.children) != 1: raise ValueError('Can only flatten when child count is 1') if self.field_path is not None: raise ValueError("Can only flatten when 'field_path' is not set") q = self.children[0] self.conn_type = q.conn_type self.field_path = q.field_path self.op = q.op self.value = q.value self.query_string = q.query_string self.children = q.children def clean(self, version): # Do some basic checks on the attributes, using a generic folder. to_xml() does a really good job of # validating. There's no reason to replicate much of that here. from .folders import Folder self.to_xml(folders=[Folder()], version=version, applies_to=Restriction.ITEMS) @classmethod def _lookup_to_op(cls, lookup): return { cls.LOOKUP_NOT: cls.NE, cls.LOOKUP_GT: cls.GT, cls.LOOKUP_GTE: cls.GTE, cls.LOOKUP_LT: cls.LT, cls.LOOKUP_LTE: cls.LTE, cls.LOOKUP_EXACT: cls.EXACT, cls.LOOKUP_IEXACT: cls.IEXACT, cls.LOOKUP_CONTAINS: cls.CONTAINS, cls.LOOKUP_ICONTAINS: cls.ICONTAINS, cls.LOOKUP_STARTSWITH: cls.STARTSWITH, cls.LOOKUP_ISTARTSWITH: cls.ISTARTSWITH, cls.LOOKUP_EXISTS: cls.EXISTS, }[lookup] @classmethod def _conn_to_xml(cls, conn_type): xml_tag_map = { cls.AND: 't:And', cls.OR: 't:Or', cls.NOT: 't:Not', } return create_element(xml_tag_map[conn_type]) @classmethod def _op_to_xml(cls, op): xml_tag_map = { cls.EQ: 't:IsEqualTo', cls.NE: 't:IsNotEqualTo', cls.GTE: 't:IsGreaterThanOrEqualTo', cls.LTE: 't:IsLessThanOrEqualTo', cls.LT: 't:IsLessThan', cls.GT: 't:IsGreaterThan', cls.EXISTS: 't:Exists', } if op in xml_tag_map: return create_element(xml_tag_map[op]) valid_ops = cls.EXACT, cls.IEXACT, cls.CONTAINS, cls.ICONTAINS, cls.STARTSWITH, cls.ISTARTSWITH if op not in valid_ops: raise ValueError("'op' %s must be one of %s" % (op, valid_ops)) # For description of Contains attribute values, see # https://docs.microsoft.com/en-us/exchange/client-developer/web-service-reference/contains # # Possible ContainmentMode values: # FullString, Prefixed, Substring, PrefixOnWords, ExactPhrase # Django lookups have no equivalent of PrefixOnWords and ExactPhrase (and I'm unsure how they actually # work). # # EWS has no equivalent of '__endswith' or '__iendswith'. That could be emulated using '__contains' and # '__icontains' and filtering results afterwards in Python. But it could be inefficient because we might be # fetching and discarding a lot of non-matching items, plus we would need to always fetch the field we're # matching on, to be able to do the filtering. I think it's better to leave this to the consumer, i.e.: # # items = [i for i in fld.filter(subject__contains=suffix) if i.subject.endswith(suffix)] # items = [i for i in fld.filter(subject__icontains=suffix) if i.subject.lower().endswith(suffix.lower())] # # Possible ContainmentComparison values (there are more, but the rest are "To be removed"): # Exact, IgnoreCase, IgnoreNonSpacingCharacters, IgnoreCaseAndNonSpacingCharacters # I'm unsure about non-spacing characters, but as I read # https://en.wikipedia.org/wiki/Graphic_character#Spacing_and_non-spacing_characters # we shouldn't ignore them ('a' would match both 'a' and 'å', the latter having a non-spacing character). if op in {cls.EXACT, cls.IEXACT}: match_mode = 'FullString' elif op in (cls.CONTAINS, cls.ICONTAINS): match_mode = 'Substring' elif op in (cls.STARTSWITH, cls.ISTARTSWITH): match_mode = 'Prefixed' else: raise ValueError('Unsupported op: %s' % op) if op in (cls.IEXACT, cls.ICONTAINS, cls.ISTARTSWITH): compare_mode = 'IgnoreCase' else: compare_mode = 'Exact' return create_element( 't:Contains', attrs=OrderedDict([ ('ContainmentMode', match_mode), ('ContainmentComparison', compare_mode), ]) ) def is_leaf(self): return not self.children def is_empty(self): return self.is_leaf() and self.field_path is None and self.query_string is None def expr(self): if self.is_empty(): return None if self.query_string: return self.query_string if self.is_leaf(): expr = '%s %s %r' % (self.field_path, self.op, self.value) else: # Sort children by field name so we get stable output (for easier testing). Children should never be empty. expr = (' %s ' % (self.AND if self.conn_type == self.NOT else self.conn_type)).join( (c.expr() if c.is_leaf() or c.conn_type == self.NOT else '(%s)' % c.expr()) for c in sorted(self.children, key=lambda i: i.field_path or '') ) if self.conn_type == self.NOT: # Add the NOT operator. Put children in parens if there is more than one child. if self.is_leaf() or len(self.children) == 1: return self.conn_type + ' %s' % expr return self.conn_type + ' (%s)' % expr return expr def to_xml(self, folders, version, applies_to): if self.query_string: if version.build < EXCHANGE_2010: raise NotImplementedError('QueryString filtering is only supported for Exchange 2010 servers and later') elem = create_element('m:QueryString') elem.text = self.query_string return elem # Translate this Q object to a valid Restriction XML tree elem = self.xml_elem(folders=folders, version=version, applies_to=applies_to) if elem is None: return None restriction = create_element('m:Restriction') restriction.append(elem) return restriction def _check_integrity(self): if self.is_empty(): return if self.query_string: if any([self.field_path, self.op, self.value, self.children]): raise ValueError('Query strings cannot be combined with other settings') return if self.conn_type not in self.CONN_TYPES: raise ValueError("'conn_type' %s must be one of %s" % (self.conn_type, self.CONN_TYPES)) if not self.is_leaf(): return if not self.field_path: raise ValueError("'field_path' must be set") if self.op not in self.OP_TYPES: raise ValueError("'op' %s must be one of %s" % (self.op, self.OP_TYPES)) if self.op == self.EXISTS: if self.value is not True: raise ValueError("'value' must be True when operator is EXISTS") if self.value is None: raise ValueError('Value for filter on field path "%s" cannot be None' % self.field_path) if is_iterable(self.value, generators_allowed=True): raise ValueError( 'Value %r for filter on field path "%s" must be a single value' % (self.value, self.field_path) ) def _validate_field_path(self, field_path, folder, applies_to, version): from .indexed_properties import MultiFieldIndexedElement if applies_to == Restriction.FOLDERS: # This is a restriction on Folder fields folder.validate_field(field=field_path.field, version=version) else: folder.validate_item_field(field=field_path.field, version=version) if not field_path.field.is_searchable: raise ValueError("EWS does not support filtering on field '%s'" % field_path.field.name) if field_path.subfield and not field_path.subfield.is_searchable: raise ValueError("EWS does not support filtering on subfield '%s'" % field_path.subfield.name) if issubclass(field_path.field.value_cls, MultiFieldIndexedElement) and not field_path.subfield: raise ValueError("Field path '%s' must contain a subfield" % self.field_path) def _get_field_path(self, folders, applies_to, version): # Convert the string field path to a real FieldPath object. The path is validated using the given folders. from .fields import FieldPath for folder in folders: try: if applies_to == Restriction.FOLDERS: # This is a restriction on Folder fields field = folder.get_field_by_fieldname(fieldname=self.field_path) field_path = FieldPath(field=field) else: field_path = FieldPath.from_string(field_path=self.field_path, folder=folder) except ValueError: continue self._validate_field_path(field_path=field_path, folder=folder, applies_to=applies_to, version=version) break else: raise InvalidField("Unknown field path %r on folders %s" % (self.field_path, folders)) return field_path def _get_clean_value(self, field_path, version): if self.op == self.EXISTS: return None clean_field = field_path.subfield if (field_path.subfield and field_path.label) else field_path.field if clean_field.is_list: # With __contains, we allow filtering by only one value even though the field is a list type return clean_field.clean(value=[self.value], version=version)[0] else: return clean_field.clean(value=self.value, version=version) def xml_elem(self, folders, version, applies_to): # Recursively build an XML tree structure of this Q object. If this is an empty leaf (the equivalent of Q()), # return None. from .indexed_properties import SingleFieldIndexedElement from .extended_properties import ExtendedProperty from .fields import DateTimeBackedDateField # Don't check self.value just yet. We want to return error messages on the field path first, and then the value. # This is done in _get_field_path() and _get_clean_value(), respectively. self._check_integrity() if self.is_empty(): return None if self.is_leaf(): elem = self._op_to_xml(self.op) field_path = self._get_field_path(folders, applies_to=applies_to, version=version) clean_value = self._get_clean_value(field_path=field_path, version=version) if issubclass(field_path.field.value_cls, ExtendedProperty) and field_path.field.value_cls.is_binary_type(): # We need to base64-encode binary data clean_value = base64.b64encode(clean_value.value).decode('ascii') elif issubclass(field_path.field.value_cls, SingleFieldIndexedElement) and not field_path.label: # We allow a filter shortcut of e.g. email_addresses__contains=EmailAddress(label='Foo', ...) instead of # email_addresses__Foo_email_address=.... Set FieldPath label now so we can generate the field_uri. field_path.label = clean_value.label elif isinstance(field_path.field, DateTimeBackedDateField): # We need to convert to datetime clean_value = field_path.field.date_to_datetime(clean_value) elem.append(field_path.to_xml()) constant = create_element('t:Constant') if self.op != self.EXISTS: # Use .set() to not fill up the create_element() cache with unique values constant.set('Value', value_to_xml_text(clean_value)) if self.op in self.CONTAINS_OPS: elem.append(constant) else: uriorconst = create_element('t:FieldURIOrConstant') uriorconst.append(constant) elem.append(uriorconst) elif len(self.children) == 1: # We have only one child elem = self.children[0].xml_elem(folders=folders, version=version, applies_to=applies_to) else: # We have multiple children. If conn_type is NOT, then group children with AND. We'll add the NOT later elem = self._conn_to_xml(self.AND if self.conn_type == self.NOT else self.conn_type) # Sort children by field name so we get stable output (for easier testing). Children should never be empty for c in sorted(self.children, key=lambda i: i.field_path or ''): elem.append(c.xml_elem(folders=folders, version=version, applies_to=applies_to)) if elem is None: return None # Should not be necessary, but play safe if self.conn_type == self.NOT: # Encapsulate everything in the NOT element not_elem = self._conn_to_xml(self.conn_type) not_elem.append(elem) return not_elem return elem def __and__(self, other): # & operator. Return a new Q with two children and conn_type AND return self.__class__(self, other, conn_type=self.AND) def __or__(self, other): # | operator. Return a new Q with two children and conn_type OR return self.__class__(self, other, conn_type=self.OR) def __invert__(self): # ~ operator. If op has an inverse, change op. Else return a new Q with conn_type NOT if self.conn_type == self.NOT: # This is NOT NOT. Change to AND self.conn_type = self.AND if len(self.children) == 1 and self.field_path is None: self._promote() return self if self.is_leaf(): if self.op == self.EQ: self.op = self.NE return self if self.op == self.NE: self.op = self.EQ return self if self.op == self.GT: self.op = self.LTE return self if self.op == self.GTE: self.op = self.LT return self if self.op == self.LT: self.op = self.GTE return self if self.op == self.LTE: self.op = self.GT return self return self.__class__(self, conn_type=self.NOT) def __eq__(self, other): return repr(self) == repr(other) def __hash__(self): return hash(repr(self)) def __str__(self): return self.expr() or 'Q()' def __repr__(self): if self.is_leaf(): if self.query_string: return self.__class__.__name__ + '(%r)' % self.query_string return self.__class__.__name__ + '(%s %s %r)' % (self.field_path, self.op, self.value) sorted_children = tuple(sorted(self.children, key=lambda i: i.field_path or '')) if self.conn_type == self.NOT or len(self.children) > 1: return self.__class__.__name__ + repr((self.conn_type,) + sorted_children) return self.__class__.__name__ + repr(sorted_children) class Restriction: """ Implements an EWS Restriction type. """ # The type of item the restriction applies to FOLDERS = 'folders' ITEMS = 'items' RESTRICTION_TYPES = (FOLDERS, ITEMS) def __init__(self, q, folders, applies_to): if not isinstance(q, Q): raise ValueError("'q' value %r must be a Q instance" % q) if q.is_empty(): raise ValueError("Q object must not be empty") from .folders import BaseFolder for folder in folders: if not isinstance(folder, BaseFolder): raise ValueError("'folder' value %r must be a Folder instance" % folder) if applies_to not in self.RESTRICTION_TYPES: raise ValueError("'applies_to' must be one of %s" % (self.RESTRICTION_TYPES,)) self.q = q self.folders = folders self.applies_to = applies_to def to_xml(self, version): return self.q.to_xml(folders=self.folders, version=version, applies_to=self.applies_to) def __str__(self): """ Prints the XML syntax tree """ return xml_to_str(self.to_xml(version=self.folders[0].account.version))