APIs for Transactional Insertion

[xfoxfu]

It is common to have a pattern of:

1. detect if a item with a specific link exists,
2. if not,create a new item.

The two actions need to be wrapped into a transaction, which could be considered as conditional insertion, or to say upsert.

Such kind of APIs need to be provided directly, instead of letting developers write commit/rollback manually.

[xfoxfu]

Some ideas:

• add some by-name or by-link API endpoints
• let the user write commit - rollback calls