RBKubeMQ

This is a quick gem created to manage KubeMQ with Ruby.

To install ArangoRB: gem install RBKubeMQ
To use it in your application: require rbkubemq
For examples, look the tests in "/spec/lib/spec_helper".
It requires the gems "HTTParty", "Oj" and "faye-websocket".

Used classes

• RBKubeMQ::Client: to manage a general client
• RBKubeMQ::Sender: to manage a sender
• RBKubeMQ::Streamer: to create a websocket to send data
• RBKubeMQ::Subscriber: to create a websocket to receive data
• RBKubeMQ::Utility: to parse and load easier the data
• RBKubeMQ::Error: to manage generic error

RBKubeMQ::Client

Arango::Server is used to manage a connection with KubeMQ.

client = RBKubeMQ::Client.new host: "YOUR_HOST", port: "8080", tls: false # tls is true then it will make your requests with https and wss instead of http or ws

RBKubeMQ::Sender

Sender it is used to do HTTP requests to KubeMQ. It manage event, request, query and response requests.

sender = client.sender client_id: "YOUR_CLIENT", channel: "YOUR_CHANNEL",
meta: nil, store: false, timeout: 1000, cache_key: nil, cache_ttl: nil

The possible request that you can do are the following:

sender.event("YOUR MESSAGE") # send an event
sender.request("YOUR MESSAGE") # send a request (we do not expect a body)
sender.query("YOUR MESSAGE") # send a query  (we expect a body)
sender.response(received_request, message: "YOUR MESSAGE") # send a response to a request (the received request is the one received with a subscriber)

You can overwrite the default values by inserting them as attributes, like this:

sender.event("YOUR MESSAGE", client_id: "client_id")

Note that client_id, channel are mandatory values that need to be insert either at the initialization or during the request.

RBKubeMQ::Streamer

Streamer it is used to create a stream websocket that it will be used to communicate with the KubeMQ. By using an eventmachine the structure of a streamer can be similar to one of a websocket.

i = 0
EM.run do
  streamer = client.streamer(client_id: "YOUR_CLIENT", channel: "YOUR_CHANNEL",
    meta: nil, store: false)

  streamer.on :open do |event|
    p [:open]
  end

  streamer.on :message do |event|
    p [:message, RBKubeMQ::Utility.load(event.data)]
  end

  streamer.on :close do |event|
    p [:close]
    streamer = nil; EM.stop
  end

  # Send a message every second
  timer = EM::PeriodicTimer.new(1) do
    i += 1
    puts "SENDING #{i}"
    streamer.send(i, meta: "Stream")
  end
end

RBKubeMQ::Subscriber

Subscriber is liked the streamer but it is used only to subscribe to a client_id and a channel. You can use groups to subdivide the queue between different machines. It cannot be use to send data.

EM.run do
  subscriber = client.subscriber(client_id: "YOUR_CLIENT", channel: "YOUR_CHANNEL",
    group: "YOUR_GROUP")

  subscriber.on :open do |event|
    p [:open]
  end

  subscriber.on :message do |event|
    p [:message, RBKubeMQ::Utility.load(event.data)]
  end

  subscriber.on :close do |event|
    p [:close]
    subscriber = nil; EM.stop
  end
end

In the example the subscriber is for events. You can subscribe to "events_store", "commands", and "queries" by specifying "type: events_store" during the initialization.

RBKubeMQ::Utility

RBKubeMQ::Utility.dump(hash) # Convert hash in correct format for KubeMQ
RBKubeMQ::Utility.load(string) # Parse hash in human format from KubeMQ

RBKubeMQ::Error

RBKubeMQ::Error is used to manage generic errors inside of the gem.

Test

To test, create a file "config.yml" in the "spec" folder with inside:

host: YOUR_KYBEMQ_HOST

Then run the tests with rspec spec/lib/sender.rb.