omhiredis: Redis Output Module¶

Module Name: omhiredis

Original Author: Brian Knox <bknox@digitalocean.com>

Description

This module provides native support for writing to Redis, using the hiredis client library.

Action Parameters

server Name or address of the Redis server
serverport Port of the Redis server if the server is not listening on the default port.
mode Mode to run the output action in: “queue” or “publish”. If not supplied, the original “template” mode is used. Note due to a config parsing bug in 8.13, explicitly setting this to “template” mode will result in a config parsing error.
template Template is required if using “template” mode.
key Key is required if using “publish” or “queue” mode.

Examples

Mode: template

In “template” mode, the string constructed by the template is sent to Redis as a command. Note this mode has problems with strings with spaces in them - full message won’t work correctly. In this mode, the template argument is required, and the key argument is meaningless.

::

module(load=”omhiredis”)

template(: name=”program_count_tmpl” type=”string” string=”HINCRBY progcount %programname% 1”)
action(: name=”count_programs” server=”my-redis-server.example.com” port=”6379” type=”omhiredis” mode=”template” template=”program_count_tmpl”)

Here’s an example redis-cli session where we HGETALL the counts:

::: > redis-cli 127.0.0.1:6379> HGETALL progcount 1) “rsyslogd” 2) “35” 3) “rsyslogd-pstats” 4) “4302”

Mode: queue

In “queue” mode, the syslog message is pushed into a Redis list at “key”, using the LPUSH command. If a template is not supplied, the plugin will default to the RSYSLOG_ForwardFormat template.

::

module(load=”omhiredis”)

action(: name=”push_redis” server=”my-redis-server.example.com” port=”6379” type=”omhiredis” mode=”queue” key=”my_queue”)

Here’s an example redis-cli session where we RPOP from the queue:

::

> redis-cli 127.0.0.1:6379> RPOP my_queue

“<46>2015-09-17T10:54:50.080252-04:00 myhost rsyslogd: [origin software=”rsyslogd” swVersion=”8.13.0.master” x-pid=”6452” x-info=”http://www.rsyslog.com“] start”

127.0.0.1:6379>

Mode: publish

In “publish” mode, the syslog message is published to a Redis topic set by “key”. If a template is not supplied, the plugin will default to the RSYSLOG_ForwardFormat template.

::

module(load=”omhiredis”)

action(: name=”publish_redis” server=”my-redis-server.example.com” port=”6379” type=”omhiredis” mode=”publish” key=”my_channel”)

Here’s an example redis-cli session where we SUBSCRIBE to the topic:

::

> redis-cli

127.0.0.1:6379> subscribe my_channel

Reading messages... (press Ctrl-C to quit)

“subscribe”
“my_channel”
(integer) 1

“message”
“my_channel”
“<46>2015-09-17T10:55:44.486416-04:00 myhost rsyslogd-pstats: {“name”:”imuxsock”,”origin”:”imuxsock”,”submitted”:0,”ratelimit.discarded”:0,”ratelimit.numratelimiters”:0}”

This documentation is part of the rsyslog project.