System and method for logical deletion of stored data objects

摘要

Systems and methods for providing object versioning in a storage system may support the logical deletion of stored objects. In response to a delete operation specifying both a user key and a version identifier, the storage system may permanently delete the specified version of an object having the specified key. In response to a delete operation specifying a user key, but not a version identifier, the storage system may create a delete marker object that does not contain object data, and may generate a new version identifier for the delete marker. The delete marker may be stored as the latest object version of the user key, and may be addressable in the storage system using a composite key comprising the user key and the new version identifier. Subsequent attempts to retrieve the user key without specifying a version identifier may return an error, although the object was not actually deleted.

主权项

1. A system, comprising:
a data store that stores a plurality of objects, wherein each of the plurality of objects comprises a user key and a version identifier, wherein at least two of the plurality of objects further comprise object data, and wherein at least two versions of at least two of the plurality of objects correspond to respective access control lists; one or more processors; a memory coupled to the one or more processors and storing program instructions that when executed by the one or more processors cause the one or more processors to perform:
receiving a request, from a requester, to retrieve a particular access control list corresponding to a particular object version of a particular object from the data store, wherein the request specifies a user key; andin response to receiving the request to retrieve the particular access control list:
determining whether the particular object version is a delete marker object comprising the specified user key, wherein the presence of a delete marker object comprising the specified user key in the data store indicates a prior logical deletion of the particular object from the data store;determining whether the requester has permission to retrieve the particular access control list;in response to determining that the particular object version is a delete marker object comprising the specified user key, returning an error indication;in response to determining that the requester does not have permission to retrieve the particular access control list, returning an error indication; andin response to determining that the particular object version is not a delete marker object and that the requester has permission to retrieve the particular access control list, returning the particular access control list.