.. _library_redis:

``redis``
=========

Redis client library. Supports GNU Prolog, XVM, SICStus Prolog,
SWI-Prolog, and XSB. Support for Ciao Prolog and ECLiPSe is also
included but requires fixes for issues in these systems.

For general information on Redis, including a list of the available
commands, visit:

::

   https://redis.io

API documentation
-----------------

Open the
`../../docs/library_index.html#redis <../../docs/library_index.html#redis>`__
link in a web browser.

Loading
-------

To load this library, load the ``loader.lgt`` file:

::

   | ?- logtalk_load(redis(loader)).

Testing
-------

To test this library predicates, load the ``tester.lgt`` file:

::

   | ?- logtalk_load(redis(tester)).

The tests assume a localhost Redis server running on the default port
(6379) if the ``REDIS_HOST`` and ``REDIS_PORT`` environment variables
are not defined. If the server is not detected, the tests are skipped.

The unit tests were originally written by Sean Charles for his GNU
Prolog Redis client library:

::

   https://github.com/emacstheviking/gnuprolog-redisclient

The Logtalk version is a straight-forward port of the original tests
using the ``test/1`` dialect of ``lgtunit``.

Credits
-------

This library is inspired by the Sean Charles GNU Prolog Redis client
library.

Known issues
------------

Recent versions of macOS seem to disable the mapping of ``localhost`` to
``127.0.0.1``. This issue may prevent running this library unit tests
and the ``redis::connect/1`` predicate from working. This can be fixed
either by editing the
``/etc/hosts file or by using in alternative the predicate``\ redis::connect/3\ ``with``'127.0.0.1'\`
as the first argument.
