Using Rack::Proxy as a middleware instead of using it as a standard Ruby class

.travis.yml

@@ -0,0 +1,19 @@
+sudo: false
+cache: bundler
+language: ruby
+before_install:
+  - "echo 'gem: --no-ri --no-rdoc' > ~/.gemrc"
+  - gem install bundler
+  - gem update bundler
+script: bundle exec rake test
+rvm:
+  - 2.0.0
+  - 2.1.5
+  - 2.2.2
+  - 2.2.3
+  - 2.3.0
+  - 2.3.1
+env:
+ - RAILS_ENV=test RACK_ENV=test
+notifications:
+  email: false

Gemfile.lock

@@ -7,10 +7,13 @@ PATH
 GEM
   remote: http://rubygems.org/
   specs:
+    power_assert (0.2.6)
     rack (1.2.1)
     rack-test (0.5.6)
       rack (>= 1.0)
     rake (0.9.2.2)
+    test-unit (3.1.5)
+      power_assert
 
 PLATFORMS
   ruby
@@ -19,3 +22,7 @@ DEPENDENCIES
   rack-proxy!
   rack-test
   rake
+  test-unit
+
+BUNDLED WITH
+   1.12.4

README.md

@@ -1,8 +1,7 @@
-A request/response rewriting HTTP proxy. A Rack app.
-Subclass `Rack::Proxy` and provide your `rewrite_env` and `rewrite_response` methods.
+A request/response rewriting HTTP proxy. A Rack app. Subclass `Rack::Proxy` and provide your `rewrite_env` and `rewrite_response` methods.
 
-
-## Example
+Example
+-------
 
 ```ruby
 class Foo < Rack::Proxy
@@ -44,12 +43,54 @@ The same can be achieved for *all* requests going through the `Rack::Proxy` inst
 Rack::Proxy.new(ssl_verify_none: true)
 ```
 
+Using it as a middleware:
+-------------------------
+
+Example: Proxying only requests that end with ".php" could be done like this:
+
+```ruby
+require 'rack/proxy'
+class RackPhpProxy < Rack::Proxy
+
+  def perform_request(env)
+    request = Rack::Request.new(env)
+    if request.path =~ %r{\.php}
+      env["HTTP_HOST"] = "localhost"
+      env["REQUEST_PATH"] = "/php/#{request.fullpath}"
+      super(env)
+    else
+      @app.call(env)
+    end
+  end
+end
+```
+
+To use the middleware, please consider the following:
+
+1) For Rails we could add a configuration in config/application.rb
+
+```ruby
+  config.middleware.use RackPhpProxy, {ssl_verify_none: true}
+```
+
+2) For Sinatra or any Rack-based application:
+
+```ruby
+class MyAwesomeSinatra < Sinatra::Base
+   use  RackPhpProxy, {ssl_verify_none: true}
+end
+```
+
+This will allow to run the other requests through the application and only proxy the requests that match the condition from the middleware.
+
 See tests for more examples.
 
-## WARNING
+WARNING
+-------
 
 Doesn't work with fakeweb/webmock. Both libraries monkey-patch net/http code.
 
-## Todos
+Todos
+-----
 
-* Make the docs up to date with the current use case for this code: everything except streaming which involved a rather ugly monkey patch and only worked in 1.8, but does not work now.
+-	Make the docs up to date with the current use case for this code: everything except streaming which involved a rather ugly monkey patch and only worked in 1.8, but does not work now.

lib/rack/proxy.rb

@@ -39,7 +39,13 @@ def reconstruct_header_name(name)
     end
 
     # @option opts [String, URI::HTTP] :backend Backend host to proxy requests to
-    def initialize(opts = {})
+    def initialize(app = nil, opts= {})
+      if app.is_a?(Hash)
+        opts = app
+        @app = nil
+      else
+        @app = app
+      end
       @streaming = opts.fetch(:streaming, true)
       @ssl_verify_none = opts.fetch(:ssl_verify_none, false)
       @backend = URI(opts[:backend]) if opts[:backend]

rack-proxy.gemspec

@@ -21,4 +21,5 @@ Gem::Specification.new do |s|
 
   s.add_dependency("rack")
   s.add_development_dependency("rack-test")
+  s.add_development_dependency("test-unit")
 end

test/test_helper.rb

@@ -1,4 +1,6 @@
 require "rubygems"
+require 'bundler/setup'
+require 'bundler/gem_tasks'
 require "test/unit"
 
 require "rack"