Connect

Overview

Every KubeMQ application starts the same way: open a connection to the broker and prove it actually works before building anything on top of it. This tutorial is that first lesson — create a client, give it a stable identity, and confirm connectivity with a health check, so the pattern is muscle memory before you move on to real messaging.

KubeMQ::PubSubClient.new (or QueuesClient / CQClient) is constructed with an address and a client_id — the ID tags this connection in broker logs, subscriptions, and management views, so pick something stable rather than a random string. client.ping verifies the round trip cheaply: it returns broker metadata (version, uptime) instead of just "no exception," proving the client is talking to a real broker rather than silently misconfigured. client.close releases the connection; wrap it in ensure so cleanup runs even if ping raises.

Gotchas: a successful construction doesn't always mean the broker is reachable — connection can happen lazily, so ping is the only reliable proof; reusing the same client ID across running instances causes routing confusion on the broker; and forgetting close (or an ensure block) in quick scripts is a common source of leaked connections under load.

Prerequisites

• KubeMQ server running on localhost:50000
• Ruby SDK installed (gem install kubemq)

Code

require 'kubemq'

address = ENV.fetch('KUBEMQ_ADDRESS', 'localhost:50000')

begin
  client = KubeMQ::PubSubClient.new(address: address, client_id: 'connect-example')
  info = client.ping
  puts "Minimal client connected. Server: #{info.version}"
  client.close

  client = KubeMQ::QueuesClient.new(address: address, client_id: 'connect-configured')
  info = client.ping
  puts "Configured client connected. Server: #{info.version}"
  client.close
rescue KubeMQ::Error => e
  puts "KubeMQ error: #{e.message}"
ensure
  puts 'Done'
end

How It Works

• The SDK provides three client classes (PubSubClient, QueuesClient, CQClient) — each connects identically via keyword arguments.
• ping verifies connectivity and returns broker metadata including version and uptime.
• Review timeouts, channel names, and client IDs before running against shared environments.

Related

• Ruby SDK Reference
• Close
• Ping