R Bindings to 'hiredis'

A 'hiredis' wrapper that includes support for transactions, pipelining, blocking subscription, serialisation of all keys and values, 'Redis' error handling with R errors. Includes an automatically generated 'R6' interface to the full 'hiredis' API. Generated functions are faithful to the 'hiredis' documentation while attempting to match R's argument semantics. Serialisation must be explicitly done by the user, but both binary and text-mode serialisation is supported.

redux

redux provides an interface to Redis. Two interfaces are provided; a low level interface (allowing execution of arbitrary Redis commands with almost no interface) and a high-level interface with an API that matches all of the several hundred Redis commands.

As well as supporting Redis commands, redux supports:

• pipelineing: execute more than one command in a single Redis roundtrip, which can greatly increase performance, especially over high-latency connections.
• socket connections: can connect to a locally running Redis instance over a unix socket (if Redis is configured to do so) for faster communication.
• flexible serialisation: serialise any part of a Redis command, including keys and fields. Binary serialisation is supported via object_to_bin / bin_to_object, which are thin wrappers around serialize / unserialize
• subscriptions: create a simple blocking subscribe client, applying a callback function to every message received.
• error handling: Every Redis error becomes an R error.

redux also provides a driver for storr, allowing easy exchange of R objects between computers.

Usage

Create a hiredis object:

r <- redux::hiredis()

The hiredis object is a hiredis object with many (many methods), each corresponding to a different Redis command.

r
## <redis_api>
##   Redis commands:
##     APPEND: function
##     AUTH: function
##     BGREWRITEAOF: function
##     BGSAVE: function
##     ...
##     ZSCORE: function
##     ZUNIONSTORE: function
##   Other public methods:
##     clone: function
##     command: function
##     config: function
##     initialize: function
##     pipeline: function
##     reconnect: function
##     subscribe: function
##     type: function

All the methods are available from this object; for example to set "foo" to "bar", use:

r$SET("foo", "bar")

See the package vignette for more information (vignette("redux")) or https://richfitz.github.io/redux/articles/redux.html

Testing

To use the test suite, please set the environment variables

• NOT_CRAN=true
• REDUX_TEST_USE_REDIS=true
• REDUX_TEST_ISOLATED=true

The first two opt in to using redis at all, and the third activates commands that may be destructive or undesirable to use on a production server.

Installation

Install from CRAN with

install.packages("redux")

or install the development version with

remotes::install_github("richfitz/redux", upgrade = FALSE)

See also

There is considerable prior work in this space:

• rredis, the original R Redis client
• RcppRedis, Dirk Eddelbuettel's R Redis client, which greatly influenced the design decisions here
• hiredis-rb, the Ruby Redis client that inspired the subscribe and pipeline support here.
• rrlite, an almost identical interface to rlite, a serverless-zero configuration database with an identical interface to Redis

License

GPL-2 © Rich FitzJohn.