kumomta/docs/reference/redis/open.md

redis.open { PARAMS }

Opens a connection to a Redis data store and returns a connection handle.

local redis = require 'redis'

-- Open a connection and increment a counter, returning its new value
local conn = redis.open { node = 'redis://127.0.0.1/' }
print(conn:query('incr', 'test-count'))

PARAMS is a lua table with the following keys:

• node - the redis URL string identifying the server. Can be a table listing multiple servers if you have a redis cluster deployed.

• pool_size - optional integer. Specifies the maximum number of spare connections to be maintained by the connection pool. The default is 10.

• read_from_replicas - optional boolean. If true, when connecting to a redis cluster, reads are issued to replicas while writes are issued to the primary data stores.

• username - optional string. convenience for working with the cluster, so that you only need to specify the username once. This is not used for connecting to a single node.

• password - optional string. convenience for working with the cluster, so that you only need to specify the password once. This is not used for connecting to a single node.

• connect_timeout - optional string. Specify how long to keep attempting to connect to redis. The default is 30 seconds. {{since('dev', inline=True)}}

The returned connection handle has a single "query" method:

conn:query(CMD, [ARGS])

Issue a redis command and return the result.

See Redis Commands for a list of commands.

The redis INCRBY command increments a key by a value; it has the syntax:

INCRBY key increment

To use INCRBY to increment my-key by 2:

conn:query("INCRBY", "my-key", 2)