add initializer on Faraday::Adapter that accept and store a block wit…

…h custom configuration

use the `@custom_config` block on `net_http` and `net_http_persistent` adapters
added tests

lib/faraday/adapter.rb

@@ -30,6 +30,11 @@ def inherited(subclass)
     extend Parallelism
     self.supports_parallel = false
 
+    def initialize(app = nil, &block)
+      super
+      @custom_config = block if block_given?
+    end
+
     def call(env)
       env.clear_body if env.needs_body?
     end

lib/faraday/adapter/net_http.rb

@@ -32,10 +32,7 @@ def call(env)
         super
         with_net_http_connection(env) do |http|
           configure_ssl(http, env[:ssl]) if env[:url].scheme == 'https' and env[:ssl]
-
-          req = env[:request]
-          http.read_timeout = http.open_timeout = req[:timeout] if req[:timeout]
-          http.open_timeout = req[:open_timeout]                if req[:open_timeout]
+          configure_request(http, env[:request])
 
           begin
             http_response = perform_request(http, env)
@@ -109,6 +106,13 @@ def configure_ssl(http, ssl)
         http.ssl_version  = ssl[:version]      if ssl[:version]
       end
 
+      def configure_request(http, req)
+        http.read_timeout = http.open_timeout = req[:timeout] if req[:timeout]
+        http.open_timeout = req[:open_timeout]                if req[:open_timeout]
+
+        @custom_config.call(http) if @custom_config
+      end
+
       def ssl_cert_store(ssl)
         return ssl[:cert_store] if ssl[:cert_store]
         # Use the default cert store by default, i.e. system ca certs

lib/faraday/adapter/net_http_persistent.rb

@@ -7,18 +7,19 @@ class Adapter
     class NetHttpPersistent < NetHttp
       dependency 'net/http/persistent'
 
-      def with_net_http_connection(env)
-        if proxy = env[:request][:proxy]
+      def net_http_connection(env)
+        if (proxy = env[:request][:proxy])
           proxy_uri = ::URI::HTTP === proxy[:uri] ? proxy[:uri].dup : ::URI.parse(proxy[:uri].to_s)
           proxy_uri.user = proxy_uri.password = nil
           # awful patch for net-http-persistent 2.8 not unescaping user/password
           (class << proxy_uri; self; end).class_eval do
             define_method(:user) { proxy[:user] }
             define_method(:password) { proxy[:password] }
           end if proxy[:user]
+          return Net::HTTP::Persistent.new 'Faraday', proxy_uri
         end
 
-        yield Net::HTTP::Persistent.new 'Faraday', proxy_uri
+        Net::HTTP::Persistent.new 'Faraday'
       end
 
       def perform_request(http, env)

test/adapters/net_http_persistent_test.rb

@@ -16,5 +16,17 @@ def setup
       end if ssl_mode?
     end
 
+    def test_custom_adapter_config
+      url = URI('https://example.com:1234')
+
+      adapter = Faraday::Adapter::NetHttpPersistent.new do |http|
+        http.idle_timeout = 123
+      end
+
+      http = adapter.net_http_connection(:url => url, :request => {})
+      adapter.configure_request(http, {})
+
+      assert_equal 123, http.idle_timeout
+    end
   end
 end

test/adapters/net_http_test.rb

@@ -40,5 +40,17 @@ def test_explicit_port_number
       assert_equal 1234, http.port
     end
 
+    def test_custom_adapter_config
+      url = URI('https://example.com:1234')
+
+      adapter = Faraday::Adapter::NetHttp.new do |http|
+        http.continue_timeout = 123
+      end
+
+      http = adapter.net_http_connection(:url => url, :request => {})
+      adapter.configure_request(http, {})
+
+      assert_equal 123, http.continue_timeout
+    end
   end
 end