From 90f081f9cf602fa1b75b74fad58977dd40111949 Mon Sep 17 00:00:00 2001
From: Masakazu Kitajo <mkitajou@yahoo-corp.jp>
Date: Thu, 14 Jul 2016 10:30:42 -0700
Subject: [PATCH] Add request_headers option

---
 include/urdl/detail/http_read_stream.hpp | 71 +++++++++++++++++-------
 include/urdl/http.hpp                    | 69 +++++++++++++++++++++++
 2 files changed, 121 insertions(+), 19 deletions(-)

diff --git a/include/urdl/detail/http_read_stream.hpp b/include/urdl/detail/http_read_stream.hpp
index 720bec7..bf9974c 100644
--- a/include/urdl/detail/http_read_stream.hpp
+++ b/include/urdl/detail/http_read_stream.hpp
@@ -22,6 +22,7 @@
 #include <algorithm>
 #include <ostream>
 #include <iterator>
+#include <map>
 #include "urdl/http.hpp"
 #include "urdl/option_set.hpp"
 #include "urdl/url.hpp"
@@ -86,6 +87,8 @@ class http_read_stream
       = options_.get_option<urdl::http::request_content_type>().value();
     std::string user_agent
       = options_.get_option<urdl::http::user_agent>().value();
+    std::map<std::string, std::string> headers
+      = options_.get_option<urdl::http::request_headers>().value();
 
     // Form the request. We specify the "Connection: close" header so that the
     // server will close the socket after transmitting the response. This will
@@ -94,23 +97,37 @@ class http_read_stream
     request_stream << request_method << " ";
     request_stream << u.to_string(url::path_component | url::query_component);
     request_stream << " HTTP/1.0\r\n";
-    request_stream << "Host: ";
-    request_stream << u.to_string(url::host_component | url::port_component);
-    request_stream << "\r\n";
-    request_stream << "Accept: */*\r\n";
+    if (headers.find("Host") == headers.end()) {
+      request_stream << "Host: ";
+      request_stream << u.to_string(url::host_component | url::port_component);
+      request_stream << "\r\n";
+    }
+    if (headers.find("Accept") == headers.end()) {
+      request_stream << "Accept: */*\r\n";
+    }
+
     if (request_content.length())
     {
-      request_stream << "Content-Length: ";
-      request_stream << request_content.length() << "\r\n";
-      if (request_content_type.length())
+      if (headers.find("Content-Length") == headers.end()) {
+        request_stream << "Content-Length: ";
+        request_stream << request_content.length() << "\r\n";
+      }
+      if (request_content_type.length() && headers.find("Content-Type") == headers.end())
       {
         request_stream << "Content-Type: ";
         request_stream << request_content_type << "\r\n";
       }
     }
-    if (user_agent.length())
+    if (user_agent.length() && headers.find("User-Agent") == headers.end())
       request_stream << "User-Agent: " << user_agent << "\r\n";
-    request_stream << "Connection: close\r\n\r\n";
+    if (headers.find("Connection") == headers.end())
+      request_stream << "Connection: close\r\n";
+
+    for (std::map<std::string, std::string>::const_iterator itr = headers.begin(); itr != headers.end(); ++itr) {
+      request_stream << itr->first << ": " << itr->second << "\r\n";
+    }
+    request_stream << "\r\n";
+
     request_stream << request_content;
 
     // Send the request.
@@ -236,6 +253,8 @@ class http_read_stream
           = options_.get_option<urdl::http::request_content_type>().value();
         std::string user_agent
           = options_.get_option<urdl::http::user_agent>().value();
+        std::map<std::string, std::string> headers
+          = options_.get_option<urdl::http::request_headers>().value();
 
         // Form the request. We specify the "Connection: close" header so that
         // the server will close the socket after transmitting the response.
@@ -246,24 +265,38 @@ class http_read_stream
         request_stream << url_.to_string(
             url::path_component | url::query_component);
         request_stream << " HTTP/1.0\r\n";
-        request_stream << "Host: ";
-        request_stream << url_.to_string(
-            url::host_component | url::port_component);
-        request_stream << "\r\n";
-        request_stream << "Accept: */*\r\n";
+        if (headers.find("Host") == headers.end()) {
+          request_stream << "Host: ";
+          request_stream << url_.to_string(
+              url::host_component | url::port_component);
+          request_stream << "\r\n";
+        }
+        if (headers.find("Accept") == headers.end()) {
+          request_stream << "Accept: */*\r\n";
+        }
+
         if (request_content.length())
         {
-          request_stream << "Content-Length: ";
-          request_stream << request_content.length() << "\r\n";
-          if (request_content_type.length())
+          if (headers.find("Content-Length") == headers.end()) {
+            request_stream << "Content-Length: ";
+            request_stream << request_content.length() << "\r\n";
+          }
+          if (request_content_type.length() && headers.find("Content-Type") == headers.end())
           {
             request_stream << "Content-Type: ";
             request_stream << request_content_type << "\r\n";
           }
         }
-        if (user_agent.length())
+        if (user_agent.length() && headers.find("User-Agent") == headers.end())
           request_stream << "User-Agent: " << user_agent << "\r\n";
-        request_stream << "Connection: close\r\n\r\n";
+        if (headers.find("Connection") == headers.end())
+          request_stream << "Connection: close\r\n";
+
+        for (std::map<std::string, std::string>::const_iterator itr = headers.begin(); itr != headers.end(); ++itr) {
+          request_stream << itr->first << ": " << itr->second << "\r\n";
+        }
+        request_stream << "\r\n";
+
         request_stream << request_content;
       }
 
diff --git a/include/urdl/http.hpp b/include/urdl/http.hpp
index 4442b84..f6480b6 100644
--- a/include/urdl/http.hpp
+++ b/include/urdl/http.hpp
@@ -12,6 +12,7 @@
 #define URDL_HTTP_HPP
 
 #include <string>
+#include <map>
 #include <boost/system/error_code.hpp>
 #include "urdl/detail/config.hpp"
 
@@ -104,6 +105,74 @@ class request_method
   std::string value_;
 };
 
+/// Option to send arbitrary HTTP headers.
+/**
+ * @par Remarks
+ * The default is no additional headers.
+ *
+ * @par Example
+ * To add a header to the HTTP request using an object of class @c std::map:
+ * @code
+ * std::map<std::string, std::string> headers = {
+ *   {"X-Foo", "bar"}
+ * };
+ * urdl::istream is;
+ * is.set_option(urdl::http::request_heders(headers));
+ * is.open("http://host/path");
+ * @endcode
+ *
+ * @par Requirements
+ * @e Header: @c <urdl/http.hpp> @n
+ * @e Namespace: @c urdl::http
+ */
+class request_headers {
+public:
+  /// Constructs an object of class @c request_headers.
+  /**
+   * @par Remarks
+   * Postcondition: <tt>value() == Empty map</tt>.
+   */
+  request_headers()
+  {
+  }
+
+  /// Constructs an object of class @c request_headers.
+  /**
+   * @param v The desired header names and values for the option.
+   *
+   * @par Remarks
+   * Postcondition: <tt>value() == v</tt>
+   */
+  explicit request_headers(const std::map<std::string, std::string>& v)
+    : value_(v)
+  {
+  }
+
+  /// Gets the value of the option.
+  /**
+   * @returns The value of the option.
+   */
+  std::map<std::string, std::string> value() const
+  {
+    return value_;
+  }
+
+  /// Sets the value of the option.
+  /**
+   * @param v The desired header names and values for the option.
+   *
+   * @par Remarks
+   * Postcondition: <tt>value() == v</tt>
+   */
+  void value(const std::map<std::string, std::string>& v)
+  {
+    value_ = v;
+  }
+
+private:
+  std::map<std::string, std::string> value_;
+};
+
 /// Option to specify content to accompany an HTTP request.
 /**
  * @par Remarks