redis-lua is a pure Lua client library for the Redis advanced key-value database.
- Support for Redis >= 1.2
- Command pipelining
- Redis transactions (MULTI/EXEC) with CAS
- User-definable commands
- UNIX domain sockets (when available in LuaSocket)
This library is tested and works with Lua 5.1, Lua 5.2 (using a compatible version of LuaSocket) and LuaJit 2.0.
Just require the redis module assigning it to a variable:
localredis=require'redis'Previous versions of the library defined a global Redis alias as soon as the module was
imported by the user. This global alias is still defined but it is considered deprecated
and it will be removed in the next major version.
localredis=require'redis'localclient=redis.connect('127.0.0.1', 6379)
localresponse=client:ping() -- trueIt is also possible to connect to a local redis instance using UNIX domain sockets if LuaSocket has been compiled with them enabled (unfortunately it is not the default):
localredis=require'redis'localclient=redis.connect('unix:///tmp/redis.sock')client:set('usr:nrk', 10)
client:set('usr:nobody', 5)
localvalue=client:get('usr:nrk') -- 10for_,vinipairs({ 10,3,2,6,1,4,23 }) doclient:rpush('usr:nrk:ids',v)
endlocalsorted=client:sort('usr:nrk:ids', {
sort='asc', alpha=true, limit= { 1, 5 }
}) -- {1=10,2=2,3=23,4=3,5=4}localreplies=client:pipeline(function(p)
p:incrby('counter', 10)
p:incrby('counter', 30)
p:get('counter')
end)Some commands such as RPUSH, SADD, SINTER and others have been improved in Redis 2.4
to accept a list of values or keys depending on the nature of the command. Sometimes
it can be useful to pass these arguments as a list in a table, but since redis-lua does
not currently do anything to handle such a case you can use unpack() albeit with a
limitation on the maximum number of items which is defined in Lua by LUAI_MAXCSTACK
(the default on Lua 5.1 is set to 8000, see luaconf.h):
localvalues= { 'value1', 'value2', 'value3' }
client:rpush('list', unpack(values))
-- the previous line has the same effect of the following one:client:rpush('list', 'value1', 'value2', 'value3')localreplies=client:transaction(function(t)
t:incrby('counter', 10)
t:incrby('counter', 30)
t:get('counter')
end)localoptions= { watch="key_to_watch", cas=true, retry=2 }
localreplies=client:transaction(options, function(t)
localval=t:get("key_to_watch")
t:multi()
t:set("akey", val)
t:set("anotherkey", val)
end)fork,vinpairs(client:info()) doprint(k..' => ' ..tostring(v))
end--[[redis_git_dirty => 0redis_git_sha1 => aaed0894process_id => 23115vm_enabled => 0hash_max_zipmap_entries => 64expired_keys => 9changes_since_last_save => 2role => masterlast_save_time => 1283621624used_memory => 537204bgsave_in_progress => 0redis_version => 2.0.0multiplexing_api => epolltotal_connections_received => 314db0 => {keys=3,expires=0}pubsub_patterns => 0used_memory_human => 524.61Kpubsub_channels => 0uptime_in_seconds => 1033connected_slaves => 0connected_clients => 1bgrewriteaof_in_progress => 0blocked_clients => 0arch_bits => 32total_commands_processed => 3982hash_max_zipmap_value => 512db15 => {keys=1,expires=0}uptime_in_days => 0]]- Lua 5.1 and 5.2 or LuaJIT 2.0
- LuaSocket 2.0
- Telescope (required to run the test suite)
The code for redis-lua is distributed under the terms of the MIT/X11 license (see LICENSE).