Embedded Redis server for Erlang

Start Redis as an Erlang application. Project inspired by kstyrc/embedded-redis.

Using in your project

As a rebar dependency

{deps, [
  {erl_embedded_redis, ".*",
    {git, "https://github.com/gossiperl/erl_embedded_redis.git", {tag, "3.0.3"}}}
]}.

rebar get-deps compile

Directly from terminal

git clone git://github.com/gossiperl/erl_embedded_redis.git
cd erl_embedded_redis
./rebar get-deps compile
erl -pa ebin/ -pa deps/*/ebin
{ok, R} = redis:start_link(server).
{ok, Timestamp} = redis:lastsave(R).
redis:stop(server, R).

Supported operations

The redis module supports all Redis server commands except of monitor.

Custom configuration

To start Redis with custom configuration, do the following:

Cfg = [ { <<"port">>, <<"19000">> }, { <<"requirepass">>, <<"meh">> } ].
{ok, R} = redis:start_link(server, Cfg).

All keys and values in the Cfg proplist must be binary.

If you already have a redis.conf file which you would like to use, do the following:

CfgFromFile = redis_config:from_file( "/path/to/the/redis.conf" ).
{ok, R} = redis:start_link(server, CfgFromFile).

How does it work

erl_embedded_redis comes with a 64bit binaries of Redis for OS X and Linux. The binaries are in priv directory.

Issuing redis:start_link(server) opens an Erlang port, then an eredis client is created.

This client is used for all communication with the server and is also responsible for issuing shutdown command to Redis when redis:stor(server, Pid) is called.

The client will use a hd(value) of <<"bind">>, value of <<"port">> and value of <<"requirepass">> properties. The defaults (if not specified) are "127.0.0.1", 6379 and "" respecitely.

Every call to redis:start_link(server) will create a temp directory in the priv folder. A new redis.conf will be placed in there and the server will use that copy of the configuration. Issuing redis:stop(server, ...) will result in the temp folder being removed. Temporary configuration is a result of merge of the default redis.conf and given startup configuration where keys from given configuration take priority over defaults.

Windows is currently not supported and ARM not tested (most likely a separate redis build for ARM is required).

Known issues

• eredis client is created at least 100ms after Redis is started; as eredis is required for stopping the server, the minimum time between start_link and stop should be at least 100ms
• if your Erlang process crashes, Redis will continue running, temporary configuration will not get cleaned up either

License

Licensed under the Apache License, Version 2.0