allow proc to be called before redirecting fixes #56

README.md

@@ -198,6 +198,19 @@ config.middleware.use Rack::SslEnforcer, :only => "/login", :force_secure_cookie
 But be aware that if you do so, you have to make sure that the content of you cookie is encoded.
 This can be done using a coder with [Rack::Session::Cookie](https://github.com/rack/rack/blob/master/lib/rack/session/cookie.rb#L28-42).
 
+### Running code before redirect
+
+You may want to run some code before rack-ssl-enforcer forces a redirect.  This code could do something like log that a redirect was done, or if this is used in a Rails app, keeping the flash when redirecting:
+
+
+```ruby
+config.middleware.use Rack::SslEnforcer, :only => '/login', :before_redirect => Proc.new {
+  #keep flash on redirect
+  @request.session[:flash].keep if [email protected]? && @request.session.key?('flash') && [email protected]['flash'].empty?
+}
+```
+
+
 ## Deployment
 
 If you run your application behind a proxy (e.g. Nginx) you may need to do some configuration on that side. If you don't you may experience an infinite redirect loop.

lib/rack/ssl-enforcer.rb

@@ -22,7 +22,8 @@ def initialize(app, options={})
         :hsts                 => nil,
         :http_port            => nil,
         :https_port           => nil,
-        :force_secure_cookies => true
+        :force_secure_cookies => true,
+        :before_redirect      => nil
       }
       CONSTRAINTS_BY_TYPE.values.each do |constraints|
         constraints.each { |constraint| default_options[constraint] = nil }
@@ -43,7 +44,8 @@ def call(env)
       end
 
       if redirect_required?
-        modify_location_and_redirect
+        call_before_redirect
+        modify_location_and_redirect 
       elsif ssl_request?
         status, headers, body = @app.call(env)
         flag_cookies_as_secure!(headers) if @options[:force_secure_cookies]
@@ -79,6 +81,10 @@ def host_mismatch?
       destination_host && destination_host != @request.host
     end
 
+    def call_before_redirect
+       @options[:before_redirect].call unless @options[:before_redirect].nil?
+    end
+
     def modify_location_and_redirect
       location = "#{current_scheme}://#{@request.host}#{@request.fullpath}"
       location = replace_scheme(location, @scheme)

test/rack-ssl-enforcer_test.rb

@@ -123,6 +123,23 @@ class TestRackSslEnforcer < Test::Unit::TestCase
     end
   end
 
+  context ":before_redirect" do
+    def self.startup
+      @before_redirect_called = false
+    end
+    setup { mock_app :redirect_to => 'https://www.google.com', :before_redirect => Proc.new {
+      @before_redirect_called = true
+    }}
+    should "call before_direct when redirecting" do
+      get 'http://www.google.com/'
+      assert @before_redirect_called, "before_redirect was not called"
+    end
+    should "not call before_direct when not redirecting" do
+      get 'https://www.google.com/'
+      refute @before_redirect_called, "before_redirect was called"
+    end
+  end
+
   context ':redirect_code' do
     setup { mock_app :redirect_code => 302 }