Arm Treasure Data provides Server-Side Agent called Treasure Agent (td-agent), to collect server-side logs and events. This article explains 4 steps to streamingly import the data from Ruby applications, through Treasure Agent.

Prerequisites

• Basic knowledge of Ruby, Gems, and Bundler.
• Basic knowledge of Treasure Data.
• Ruby 1.9 or higher (for local testing).

What is Treasure Agent?

First of all, Treasure Agent (td-agent) needs to be installed on your application servers. Treasure Agent is an agent program sits within your application servers, focusing on uploading application logs to the cloud.

 

The td-logger-ruby library enables Ruby applications to post records to their local Treasure Agent. Treasure Agent in turn receives the records, buffers them, and uploads the data to the cloud every 5 minutes. Because the daemon runs on a local node, the logging latency is negligible.

How to install Treasure Agent?

To install Treasure Agent (td-agent), run one of the following commands based on your environment. The agent program is installed automatically by using the package management software for each platform like rpm/deb/dmg.

RHEL/CentOS 5,6,7

$ curl -L https://toolbelt.treasuredata.com/sh/install-redhat-td-agent3.sh | sh

Ubuntu & Debian

# 16.04 Xenial (64bit only)
$ curl -L https://toolbelt.treasuredata.com/sh/install-ubuntu-xenial-td-agent3.sh | sh
# 14.04 Trusty
$ curl -L https://toolbelt.treasuredata.com/sh/install-ubuntu-trusty-td-agent3.sh | sh
# 12.04 Precise
$ curl -L https://toolbelt.treasuredata.com/sh/install-ubuntu-precise-td-agent3.sh | sh

# Debian Stretch (64-bit only) 
$ curl -L https://toolbelt.treasuredata.com/sh/install-debian-stretch-td-agent3.sh | sh
# Debian Jessie (64-bit only)
$ curl -L https://toolbelt.treasuredata.com/sh/install-debian-jessie-td-agent3.sh | sh
# Debian Squeeze (64-bit only)
$ curl -L https://toolbelt.treasuredata.com/sh/install-debian-squeeze-td-agent2.sh | sh

Amazon Linux

$ curl -L https://toolbelt.treasuredata.com/sh/install-redhat-td-agent3.sh | sh

MacOS X 10.11+

$ open 'https://td-agent-package-browser.herokuapp.com/3/macosx/td-agent-3.1.1-0.dmg'

Windows Server 2012+

The Windows installation requires several steps detailed at:

• Installing Treasuer Agent using .msi Installer (Windows)

Opscode Chef (repository)

$ echo 'cookbook "td-agent"' >> Berksfile
$ berks install

AWS Elastic Beanstalk is also supported. Windows is NOT supported.

Modifying /etc/td-agent/td-agent.conf

Specify your API key by setting the apikey option in your /etc/td-agent/td-agent.conf file.

# Input from Logging Libraries
<source>
  type forward
  port 24224
</source>

# Treasure Data Output
<match td.*.*>
  type tdlog
  endpoint api.treasuredata.com
  apikey YOUR_API_KEY
  auto_create_table
  buffer_type file
  buffer_path /var/log/td-agent/buffer/td
  use_ssl true
</match>

Restart your agent after these lines are in place.

# Linux
$ sudo /etc/init.d/td-agent restart

# MacOS X
$ sudo launchctl unload /Library/LaunchDaemons/td-agent.plist
$ sudo launchctl load /Library/LaunchDaemons/td-agent.plist

td-agent accepts data via port 24224, buffers it (var/log/td-agent/buffer/td), and automatically uploads it into the cloud.

Using td-logger-ruby

Add the ‘td’ gem to your Gemfile.

gem 'td', "~> 0.10.6"

Initialize and post the records.

# Initialize
require 'td'
TreasureData::Logger.open_agent('td.test_db', :host=>'localhost', :port=>24224)

# Example1: login event
TD.event.post('login', {:uid=>123})

# Example2: follow event
TD.event.post('follow', {:uid=>123, :from=>'TD', :to=>'Heroku'})

# Example3: pay event
TD.event.post('pay',
              {:uid=>123, :item_name=>'Stone of Jordan',
               :category=>'ring', :price=>100, :count=>1})

Confirming Data Import

Execute the program.

$ ruby test.rb

Sending a SIGUSR1 signal will flush td-agent’s buffer. The upload starts immediately.

# Linux
$ kill -USR1 `cat /var/run/td-agent/td-agent.pid`

# MacOS X
$ sudo kill -USR1 `sudo launchctl list | grep td-agent | cut -f 1`

Using TD Console

To confirm that your data has been uploaded successfully, check your data set.

From CLI

Or,  issue the td tables command if you have a CLI.

$ td tables
+------------+------------+------+-----------+
| Database   | Table      | Type | Count     |
+------------+------------+------+-----------+
| test_db    | login      | log  | 1         |
| test_db    | follow     | log  | 1         |
| test_db    | pay        | log  | 1         |
+------------+------------+------+-----------+

Production Deployments

Use Rack-based Server Deployments

We recommend that you use unicorn, thin, mongrel, etc. Other setups have not been fully validated.

High Availability Configurations of td-agent

For high-traffic websites (more than 5 application nodes), we recommend using a high availability configuration of td-agent. This will improve data transfer reliability and query performance.

• High-Availability Configurations of td-agent

Monitoring td-agent

Monitoring td-agent itself is also important. For general monitoring methods for td-agent, see Monitoring td-agent