Size.IO Proxy

The Size.IO Proxy server is a high performance, lightweight and scalable method for collecting data locally to be relayed to the Size.IO platform in a fast and network-efficient manner with offline message queueing. Send your messages to this proxy and let it worry about delivering them to the platform. It exposes several different interfaces supporting:

• Redis clients in general
• Plain TCP that is very Shell and one-liner friendly
• Plain UDP for fast non-blocking messaging

Official documentation and code samples are available at http://size.io/developer

Starting the proxy

The size.js is an executable Node.js script. Install Node.js (http://nodejs.org/download/) on your system and then simply execute the script:

> ./size.js
29 Aug 00:53:32 - SERVER UDP Proxy bound to udp://*:6125
29 Aug 00:53:32 - SERVER TCP Proxy bound to tcp://*:6120
29 Aug 00:53:32 - SERVER Redis Proxy bound to tcp://*:6379

See below for information on how to use an upstart script to keep the service running in the background.

Configuring the proxy

The config.js file contains configuration values worth reviewing. Outside of setting a new access token, the default settings will work out of the box.

• exports.publisher_access_token should be set to an Access Token with enough permissions to publish events via the Size.IO WebSocket interface.
• exports.subscriber_access_token should be set to an Access Token with enough permissions to subscribe to events via the Size.IO WebSocket interface.
• exports.use_local_time should be set to false unless you have a strong desire to assert the time of published events.
• exports.tcp.listen_ip can be set to any desired IP address; leave it as null to listen on any address.
• exports.tcp.listen_port can be set to any desired port. It defaults to 6120
• exports.udp.listen_ip can be set to any desired IP address; leave it as null to listen on any address.
• exports.udp.listen_port can be set to any desired port. It defaults to 6125
• exports.redis.listen_ip can be set to any desired IP address; leave it as null to listen on any address.
• exports.redis.listen_port can be set to any desired port. It defaults to 6379
• exports.debug_level can be set to any of the following values:
• 0 marked as DEBUG in the output
• 1 marked as INFO in the output
• 2 marked as WARN in the output
• 3 marked as ERROR in the output
• Higher values will be marked SERVER in the log output

Client examples

For event publishing, the different client interfaces exist to support software preferences and have no strong advantages over each other. Only the Redis client interface supports subscriptions.

PHP Redis Publish

$redis = new Redis();
$redis->connect('127.0.0.1', 6379);
while (true) {
    $redis->incrby('api.get', 1);
	usleep(100000);
}

PHP Redis Subscribe

$redis = new Redis();
$redis->connect('127.0.0.1', 6379);
function echoEvent($redis, $channel, $message) {
	echo "'$channel' message: '$message'\n";
}
$redis->subscribe(array('event'), 'echoEvent');

BASH TCP Publish

for i in {1..10}; do
    printf '{"k":"api.get","v":1}' | nc 127.0.0.1 6120
    sleep 0.1
done

BASH UDP Publish

for i in {1..10}; do
    printf '{"k":"api.get","v":1}' | nc -u -w0 127.0.0.1 6125
    sleep 0.1
done

Upstart script

An upstart script has been provided to automatically start the script on system start and to cleanly stop on system shutdown. Upstart will also restart the script should it crash for any reason. Installation is easy:

• Copy the size-proxy.conf to /etc/init/
• Edit the script to set the HOME and USER variables, adapted for your sytem
• Start the proxy with sudo start size-proxy
• Stop the proxy with sudo stop size-proxy

Log files can be found in /var/log/upstart/.