Made number of threads in thread pool configurable

Changed thread pool to create threads only on first use

CHANGELOG

@@ -2,6 +2,9 @@ Features under the section marked 'Current' are completed but pending release as
 
 Features under a numbered section are complete and available in the Wrest gem.
 
+== 1.5.4
+ * Make thread pool configurable
+
 == 1.5.3
  * Implemented a thread pool for async requests using ThreadBackend
  * Updated request/response logging to include current thread id

README.md

@@ -1,6 +1,6 @@
 [![Build Status](https://travis-ci.org/c42/wrest.svg?branch=master)](https://travis-ci.org/c42/wrest)
 
-# Wrest 1.5.3
+# Wrest 1.5.4
 
 (c) Copyright 2009-2015 [Sidu Ponnappa](http://twitter.com/ponnappa). All Rights Reserved.
 
@@ -9,10 +9,7 @@ Wrest is a ruby REST/HTTP client library which
 * Allows you to use Net::HTTP or libCurl
 * Allows you to pick your Ruby: use 2.x.x, JRuby 1.7.6 (and higher), JRuby 9.0.0.0.pre2
 * Supports RFC 2616 based [caching](https://github.com/kaiwren/wrest/blob/caching/Caching.markdown)
-* **_Alpha_**
-
-      Allows you to go async: use Threads or EventMachine
-
+* Async http calls using Threads (reliable only on JRuby) or EventMachine
 * Allows you to quickly build object oriented wrappers around any web service
 * Is designed to be used as a library, not just a command line REST client (fewer class/static methods, more object oriented)
 * Is spec driven, strongly favours immutable objects and avoids class methods and setters making it better suited for use as a library, especially in multi-threaded environments
@@ -31,15 +28,16 @@ For Facebook, Twitter, Delicious, GitHub and other API examples, see http://gith
 * Basic API calls
 
     ```
-    'http://twitter.com/statuses/public_timeline.json'.to_uri.get.deserialise  # works with json and xml out of the box
-
-    'http://twitter.com/statuses/public_timeline.xml'.to_uri.get.deserialise   # see lib/wrest/components/translators to add other formats
+    # Works with json and xml out of the box
+    # See lib/wrest/components/translators to add other formats
+    
+    'https://api.github.com/repos/c42/wrest/issues'.to_uri.get.deserialize
     ```
 
 * Timeout support
 
     ```
-    'http://twitter.com/statuses/public_timeline.json'.to_uri.get(:timeout => 5).body
+    'https://api.github.com/repos/c42/wrest/issues'.to_uri.get(:timeout => 5).body
     ```
 
 * Redirect support
@@ -217,11 +215,15 @@ Asynchronous requests support pluggable backends. The default backend used for a
   Wrest::AsyncRequest.wait_for_thread_pool!
 ```
 
-You can change the default to eventmachine.
+You can change the default to eventmachine or to threads.
 
 ```
   Wrest::AsyncRequest.default_to_em!
 ```
+or
+```
+  Wrest::AsyncRequest.default_to_threads!
+```
 
 You can also override the default on Uri objects.
 
@@ -233,7 +235,16 @@ You can also override the default on Uri objects.
   end
 ```
 
-Note: The current implementation of asynchronous requests is currently in alpha and should not be used in production.
+You can decide which AsyncBackend to use at runtime through to `to_uri`'s options hash.
+
+```
+  "http://c42.in".to_uri(asynchronous_backend: ThreadBackend.new(number_of_threads)).get_async do |callback|
+    callback.on_ok do |response|
+      Wrest.logger.info "Ok."
+    end
+  end
+```
+
 
 ### Other useful stuff
 

lib/wrest/async_request.rb

@@ -27,8 +27,8 @@ def self.default_to_em!
     end
 
     # Assign default backend for asynchronous request to using threads. 
-    def self.default_to_threads!
-      self.default_backend = Wrest::AsyncRequest::ThreadBackend.new
+    def self.default_to_threads!(number_of_threads = 5)
+      self.default_backend = Wrest::AsyncRequest::ThreadBackend.new(number_of_threads)
     end
 
     # Returns the default backend, which is the ThreadBackend

lib/wrest/async_request/thread_pool.rb

@@ -14,12 +14,10 @@ def initialize(number_of_threads)
         @threads = []
         @number_of_threads = number_of_threads
         @queue = Queue.new
-        halt_on_sigint
-        halt_on_int
-        initialize_thread_pool
       end
 
       def execute_eventually(request)
+        initialize_thread_pool if @threads.empty?
         @queue.push(request)
         nil
       end
@@ -32,6 +30,8 @@ def join_pool_threads!
 
       private
       def initialize_thread_pool
+        halt_on_sigint
+        halt_on_int
         main_thread = Thread.current
         @threads =  @number_of_threads.times.map do |i|
           Thread.new do |thread|
@@ -55,9 +55,11 @@ def halt_on_int
       end
 
       def halt
-        Wrest.logger.debug "Shutting down ThreadPool..."
-        @threads.each(&:terminate)
-        Wrest.logger.debug "Halted ThreadPool, continuing with shutdown..."
+        unless @threads.empty?
+          Wrest.logger.debug "Wrest: Shutting down ThreadPool..."
+          @threads.each(&:terminate)
+          Wrest.logger.debug "Wrest: Halted ThreadPool, continuing with shutdown."
+        end
         Process.exit
       end
     end

lib/wrest/version.rb

@@ -8,5 +8,5 @@
 # See the License for the specific language governing permissions and limitations under the License.
 
 module Wrest
-  VERSION = "1.5.3"
+  VERSION = "1.5.4"
 end