basic.rb

# Copyright 2016-2018 The NATS Authors
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#

require 'nats/io/client'

nats = NATS::IO::Client.new

nats.connect(:servers => ["nats://127.0.0.1:4222"])
puts "Connected to #{nats.connected_server}"

nats.subscribe(">") do |msg, reply, subject|
  puts "Received on '#{subject} #{reply}': #{msg}"
  nats.publish(reply, "A" * 100) if reply
end

total = 0
payload = "b"
loop do
  nats.publish("hello.#{total}", payload)

  begin
    nats.flush(1)

    # Request which waits until given a response or a timeout
    msg = nats.request("hello", "world")
    puts "Received on '#{msg.subject} #{msg.reply}': #{msg.data}"

    total += 1
    sleep 0.0001 if total % 1000 == 0
  rescue NATS::IO::Timeout
    puts "ERROR: flush timeout"
  end
end