objectid
– Tools for working with MongoDB ObjectIds¶
Tools for working with MongoDB ObjectIds.
-
class
bson.objectid.
ObjectId
([oid=None])¶ Initialize a new ObjectId.
If oid is
None
, create a new (unique) ObjectId. If oid is an instance of (basestring
(str
orbytes
in python 3),ObjectId
) validate it and use that. Otherwise, aTypeError
is raised. If oid is invalid,InvalidId
is raised.Parameters: - oid (optional): a valid ObjectId (12 byte binary or 24 character hex string)
New in version 1.2.1: The oid parameter can be a
unicode
instance (that contains only hexadecimal digits).-
str(o)
Get a hex encoded version of
ObjectId
o.The following property always holds:
>>> o = ObjectId() >>> o == ObjectId(str(o)) True
This representation is useful for urls or other places where
o.binary
is inappropriate.
-
binary
¶ 12-byte binary representation of this ObjectId.
-
classmethod
from_datetime
(generation_time)¶ Create a dummy ObjectId instance with a specific generation time.
This method is useful for doing range queries on a field containing
ObjectId
instances.Warning
It is not safe to insert a document containing an ObjectId generated using this method. This method deliberately eliminates the uniqueness guarantee that ObjectIds generally provide. ObjectIds generated with this method should be used exclusively in queries.
generation_time will be converted to UTC. Naive datetime instances will be treated as though they already contain UTC.
An example using this helper to get documents where
"_id"
was generated before January 1, 2010 would be:>>> gen_time = datetime.datetime(2010, 1, 1) >>> dummy_id = ObjectId.from_datetime(gen_time) >>> result = collection.find({"_id": {"$lt": dummy_id}})
Parameters: - generation_time:
datetime
to be used as the generation time for the resulting ObjectId.
Changed in version 1.8: Properly handle timezone aware values for generation_time.
New in version 1.6.
- generation_time:
-
generation_time
¶ A
datetime.datetime
instance representing the time of generation for thisObjectId
.The
datetime.datetime
is timezone aware, and represents the generation time in UTC. It is precise to the second.Changed in version 1.8: Now return an aware datetime instead of a naive one.
New in version 1.2.
-
classmethod
is_valid
(oid)¶ Checks if a oid string is valid or not.
Parameters: - oid: the object id to validate
New in version 2.3.