7.2 Back-Ends

With standoff mode you have some options where to store you annotations and in which format. Storing annotations is done by a back-end. Before working with standoff mode, it is required to choose a back-end.

The annotations can be stored in a file on the local disk or in a central database. The JSON file back-end and the dummy back-end store them locally on disk. The JSON rest back-end (under development) stores them in a database communicating via a restful web-service.

The JSON file back-end stores the annotations in JSON format, and the names of keys of the JSON objects are configurable. The dummy back-end stores the annotations as s-expressions known from programming languages like LISP, in fact they are dumped Emacs-lisp expressions. The JSON rest back-end uses JSON to communicate with the database.

User Option: standoff-backend

Configuring, which back-end to use, is simple. There are two ways: (1) Customize the user option standoff-backend. You are automatically directed to the customization dialog if you try working with stand-off mode without a back-end. (2) Edit your Emacs startup file by adding:

(setq standoff-backend 'standoff-json-file)

for using the JSON file back-end, or

(setq standoff-backend 'standoff-dummy)

for using the dummy back-end.

Note, that the type of standoff-backend must be a feature, and thus must be quoted like a symbol.