Module: NebulousStomp

Defined in:
lib/nebulous_stomp.rb,
lib/nebulous_stomp/param.rb,
lib/nebulous_stomp/target.rb,
lib/nebulous_stomp/message.rb,
lib/nebulous_stomp/request.rb,
lib/nebulous_stomp/version.rb,
lib/nebulous_stomp/listener.rb,
lib/nebulous_stomp/msg/body.rb,
lib/nebulous_stomp/msg/header.rb,
lib/nebulous_stomp/redis_helper.rb,
lib/nebulous_stomp/redis_handler.rb,
lib/nebulous_stomp/stomp_handler.rb,
lib/nebulous_stomp/redis_handler_null.rb,
lib/nebulous_stomp/stomp_handler_null.rb

Overview

NebulousStomp

A little module that implements The Nebulous Protocol, a way of passing data over STOMP between different systems. Specifically, it allows you to send a message, a Request, and receive another message in answer, a Response. (Which is not something STOMP does, out of the box).

This library covers two specific use cases (three if you are picky):

1) Request-Response: a program that consumes incoming messages, works out what message to
   send in response, and sends it.

2) Question-Answer: a program that sends a request and then waits for a response; the other
   end of the Request-Response use case. We support optional caching of responses in Redis,
   to speed things up if your program is likely to make the same request repeatedly within a
   short time.

3) Since we are talking to Redis, we expose a basic, simple interface for you to talk to it
   yourself.

These are the externally-facing classes:

* Listener      -- implements the request-response use case
* Message       -- a Nebulous-Stomp message
* NebulousStomp -- main class
* RedisHelper   -- implements the Redis use case
* Request       -- implements the Request-Response use case; a wrapper for Message
* Target        -- represents a single Target

These classes are used internally:

* Param            -- helper class to store and return configuration
* RedisHandler     -- internal class to wrap the Redis gem
* RedisHandlerNull -- a "mock" version of  RedisHandler for use in testing
* StompHandler     -- internal class to wrap the Stomp gem
* StompHandlerNull -- a "mock" version of StompHandler for use in testing

Defined Under Namespace

Modules: Msg, Param Classes: ConnectionError, Listener, Message, NebulousError, NebulousTimeout, RedisHandler, RedisHandlerNull, RedisHelper, Request, StompHandler, StompHandlerNull, Target

Constant Summary collapse

VERSION =

Nebulous version number

"3.1.1"

Class Method Summary collapse

Class Method Details

.add_target(name, targetHash) ⇒ Object

:call-seq: NebulousStomp.add_target(name, targetHash) -> Target

Add a Nebulous target called <name> with a details as per <targetHash>.

<targetHash> must contain a send queue and a receive queue, or a NebulousError will be raised. Have a look in NebulousStomp::Target for the default hash you are overriding here.

Note that Param expects the target hash to have a :name key. We don’t; we add it in.



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# File 'lib/nebulous_stomp.rb', line 90

def self.add_target(name, targetHash) 
  t = NebulousStomp::Target.new targetHash.merge(name: name)
  Param.add_target(t)
  t
end

.get_target(name) ⇒ Object

:call-seq:

NebulousStomp.get_target(name) # -> Target

Given a target name, return the Target object.



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# File 'lib/nebulous_stomp.rb', line 102

def self.get_target(name)
  Param.get_target(name)
end

.init(paramHash = {}) ⇒ Object

:call-seq: NebulousStomp.init(paramHash) -> (nil)

Initialise library for use and override default options with any in <paramHash>.

The default options are defined in Nebulous::Param.



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# File 'lib/nebulous_stomp.rb', line 74

def self.init(paramHash={}) 
  Param.set(paramHash)
  nil
end

.logger ⇒ Object

:call-seq:

NebulousStomp.logger.info(__FILE__) { "message" }

Return a Logger instance to log things to. If one was not given to Param, return a logger instance that uses a DevNull IO object, that is, goes nowhere.



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# File 'lib/nebulous_stomp.rb', line 123

def self.logger
  Param.get_logger || Logger.new( DevNull.new )
end

.on? ⇒ Boolean

:call-seq:

Nebulous.on? -> Boolean

True if Nebulous is configured to be running

Returns:

  • (Boolean) 


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# File 'lib/nebulous_stomp.rb', line 133

def self.on?
  h = Param.get(:stompConnectHash)
  !(h.nil? || h.empty?)
end

.redis_on? ⇒ Boolean

:call-seq:

Nebulous.redis_on? -> Boolean

True if the Redis cache is configured to be running

Returns:

  • (Boolean) 


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# File 'lib/nebulous_stomp.rb', line 144

def self.redis_on?
  h = Param.get(:redisConnectHash)
  !(h.nil? || h.empty?)
end

.set_logger(logger) ⇒ Object

:call-seq:

NebulousStomp.set_logger(Logger.new STDOUT)

Set an instance of Logger to log stuff to.



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# File 'lib/nebulous_stomp.rb', line 112

def self.set_logger(logger)
  Param.set_logger(logger)
end