Application specific schema extensions for a hierarchical data structure

A method, comprising:

• performing, by one or more computing devices:
• receiving a request to access an object of a hierarchical data structure stored in a hierarchical data store, wherein the request is associated with a particular application of a plurality of applications granted access to the hierarchical data structure;
• responsive to receiving the request associated with the particular application, accessing a schema for the hierarchical data structure to identify a class of the schema applied to the object for the particular application, wherein the class of the schema was added to a common portion of the schema by the particular application or another one of the applications after the application of the schema to the hierarchical data structure and without modifying another class associated with the common portion of the schema utilized by a different one of the plurality of applications to process access requests received from the different application;
• and
• processing the request to access the object based, at least in part, on the identified class of the schema applied to the object.

A non-transitory, computer-readable storage medium, storing program instructions that when executed by one or more computing devices cause the one or more computing devices to implement:

• updating a common portion of a schema comprising one or more classes applied to a hierarchical data structure that is stored in a hierarchical data store to include an additional class without modifying the one or more classes associated with the common portion of the schema, wherein the additional class is applied for processing access requests received from a particular application of a plurality of applications granted access to the hierarchical data structure, and wherein the one or more classes are applied for processing access requests received from a different one of the plurality of applications;
• receiving a request to access an object of the hierarchical data structure from the particular application;
• accessing the schema for the hierarchical data structure to identify the additional class in the schema as applied to the object for processing the request;
• and
• processing the request to access the object based, at least in part, on the additional class in the schema.