[ARROW-840] [Python] Provide Python API for creating user-defined data types that can survive Arrow IPC

• Type: New Feature
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.14.0
• Component/s: Python
• Labels: pull-request-available
• External issue URL: https://github.com/apache/arrow/issues/15390
• Assignee: Antoine Pitrou
• Reporter: Wes McKinney
• Created: 16/Apr/17 23:38
• Updated: 11/Jan/23 07:11
• Resolved: 14/Jun/19 12:53

Description

The user will provide:

• Data type subclass that can indicate the physical storage type
• "get state" and "set state" functions for serializing custom metadata to bytes
• An optional function for "boxing" scalar values from the physical array storage

Internally, this will build on an analogous C++ API for defining user data types

Issue Links

• is depended upon by: ARROW-2428 [Python] Add API to map Arrow types (including extension types) to pandas ExtensionArray instances for to_pandas conversions
• is related to: ARROW-5610 [Python] Define extension type API in Python to "receive" or "send" a foreign extension type
• links to: GitHub Pull Request #4532