From b0e52dd24616bbfe18e9ed45282d2e6ea6402fc9 Mon Sep 17 00:00:00 2001
From: Vinnie Falco <vinnie.falco@gmail.com>
Date: Mon, 3 Jul 2017 20:33:54 -0700
Subject: [PATCH] Refactor header and message constructors:

fix #581

* request and response headers now have convenience
  constructors so important fields like method, target,
  result, and version may be set upon construction.

Actions Required:

* Evaluate each message constructor call site and
  adjust the constructor argument list as needed.
---
 CHANGELOG.md                                  |   9 +
 example/http-client/http_client.cpp           |   5 +-
 example/http-crawl/http_crawl.cpp             |   5 +-
 .../http_server_threaded.cpp                  |   9 +-
 example/server-framework/http_async_port.hpp  |   2 +-
 example/server-framework/http_sync_port.hpp   |   3 +-
 include/beast/http/impl/message.ipp           | 132 +++++++--
 include/beast/http/message.hpp                | 269 +++++++++++++-----
 test/http/message.cpp                         | 193 ++++++++-----
 test/http/string_view_body.cpp                |   3 +-
 test/http/write.cpp                           |  67 ++---
 11 files changed, 487 insertions(+), 210 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4bd26372..33c7df6c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,15 @@ HTTP:
 * basic_parser optimizations
 * Add basic_parser tests
 
+API Changes:
+
+* Refactor header and message constructors
+
+Actions Required:
+
+* Evaluate each message constructor call site and
+  adjust the constructor argument list as needed.
+
 --------------------------------------------------------------------------------
 
 Version 72:
diff --git a/example/http-client/http_client.cpp b/example/http-client/http_client.cpp
index 5440c7f1..5c3d0184 100644
--- a/example/http-client/http_client.cpp
+++ b/example/http-client/http_client.cpp
@@ -48,10 +48,7 @@ int main()
         return fail("connect", ec);
 
     // Set up an HTTP GET request message
-    http::request<http::string_body> req;
-    req.method(http::verb::get);
-    req.target("/");
-    req.version = 11;
+    http::request<http::string_body> req{http::verb::get, "/", 11};
     req.set(http::field::host, host + ":" +
         std::to_string(sock.remote_endpoint().port()));
     req.set(http::field::user_agent, BEAST_VERSION_STRING);
diff --git a/example/http-crawl/http_crawl.cpp b/example/http-crawl/http_crawl.cpp
index 8cee781b..03ae5172 100644
--- a/example/http-crawl/http_crawl.cpp
+++ b/example/http-crawl/http_crawl.cpp
@@ -75,10 +75,7 @@ main(int, char const*[])
         }
 
         // Set up an HTTP GET request
-        http::request<http::string_body> req;
-        req.version = 11;
-        req.method(http::verb::get);
-        req.target("/");
+        http::request<http::string_body> req{http::verb::get, "/", 11};
         req.set(http::field::host, host + std::string(":") + std::to_string(ep.port()));
         req.set(http::field::user_agent, BEAST_VERSION_STRING);
 
diff --git a/example/http-server-threaded/http_server_threaded.cpp b/example/http-server-threaded/http_server_threaded.cpp
index 84a00763..540a261b 100644
--- a/example/http-server-threaded/http_server_threaded.cpp
+++ b/example/http-server-threaded/http_server_threaded.cpp
@@ -60,8 +60,7 @@ private:
     http::response<http::string_view_body>
     client_error(http::status result, beast::string_view text)
     {
-        http::response<http::string_view_body> res;
-        res.result(result);
+        http::response<http::string_view_body> res{result, 11};
         res.set(http::field::server, BEAST_VERSION_STRING);
         res.set(http::field::content_type, "text/plain");
         res.set(http::field::connection, "close");
@@ -75,8 +74,7 @@ private:
     beast::http::response<beast::http::string_body>
     not_found() const
     {
-        beast::http::response<beast::http::string_body> res;
-        res.result(beast::http::status::not_found);
+        beast::http::response<beast::http::string_body> res{beast::http::status::not_found, 11};
         res.set(beast::http::field::server, BEAST_VERSION_STRING);
         res.set(beast::http::field::content_type, "text/html");
         res.set(http::field::connection, "close");
@@ -90,8 +88,7 @@ private:
     beast::http::response<beast::http::string_body>
     server_error(beast::error_code const& ec) const
     {
-        beast::http::response<beast::http::string_body> res;
-        res.result(beast::http::status::internal_server_error);
+        beast::http::response<beast::http::string_body> res{beast::http::status::internal_server_error, 11};
         res.set(beast::http::field::server, BEAST_VERSION_STRING);
         res.set(beast::http::field::content_type, "text/html");
         res.set(http::field::connection, "close");
diff --git a/example/server-framework/http_async_port.hpp b/example/server-framework/http_async_port.hpp
index 54db9266..7231ca7c 100644
--- a/example/server-framework/http_async_port.hpp
+++ b/example/server-framework/http_async_port.hpp
@@ -264,7 +264,7 @@ protected:
         // We construct the dynamic body with a 1MB limit
         // to prevent vulnerability to buffer attacks.
         //
-        parser_.emplace(1024 * 1024);
+        parser_.emplace(std::piecewise_construct, std::make_tuple(1024 * 1024));
 
         // Read just the header
         beast::http::async_read_header(
diff --git a/example/server-framework/http_sync_port.hpp b/example/server-framework/http_sync_port.hpp
index 6f581059..69fb1a68 100644
--- a/example/server-framework/http_sync_port.hpp
+++ b/example/server-framework/http_sync_port.hpp
@@ -188,7 +188,8 @@ private:
             // We construct the dynamic body with a 1MB limit
             // to prevent vulnerability to buffer attacks.
             //
-            beast::http::request_parser<beast::http::dynamic_body> parser(1024* 1024);
+            beast::http::request_parser<beast::http::dynamic_body> parser(
+                std::piecewise_construct, std::make_tuple(1024* 1024));
 
             // Read the header first
             beast::http::read_header(impl().stream(), buffer_, parser, ec);
diff --git a/include/beast/http/impl/message.ipp b/include/beast/http/impl/message.ipp
index 37216f03..af3c524a 100644
--- a/include/beast/http/impl/message.ipp
+++ b/include/beast/http/impl/message.ipp
@@ -111,6 +111,19 @@ header(Arg1&& arg1, ArgN&&... argn)
         std::forward<ArgN>(argn)...)
 {
 }
+
+#if 0
+template<class Fields>
+template<class... Args>
+header<false, Fields>::
+header(status result, unsigned version_, Args&&... args)
+    : Fields(std::forward<Args>(args)...)
+    , version(version_)
+    , result_(result)
+{
+}
+#endif
+
 template<class Fields>
 inline
 status
@@ -189,23 +202,118 @@ swap(
 //------------------------------------------------------------------------------
 
 template<bool isRequest, class Body, class Fields>
-template<class... Args>
+template<class... BodyArgs>
 message<isRequest, Body, Fields>::
-message(header_type&& h, Args&&... args)
+message(header_type&& h, BodyArgs&&... body_args)
     : header_type(std::move(h))
-    , body(std::forward<Args>(args)...)
+    , body(std::forward<BodyArgs>(body_args)...)
 {
 }
 
 template<bool isRequest, class Body, class Fields>
-template<class... Args>
+template<class... BodyArgs>
 message<isRequest, Body, Fields>::
-message(header_type const& h, Args&&... args)
+message(header_type const& h, BodyArgs&&... body_args)
     : header_type(h)
-    , body(std::forward<Args>(args)...)
+    , body(std::forward<BodyArgs>(body_args)...)
 {
 }
 
+template<bool isRequest, class Body, class Fields>
+template<class Version, class>
+message<isRequest, Body, Fields>::
+message(verb method, string_view target, Version version)
+    : header_type(method, target, version)
+{
+}
+
+template<bool isRequest, class Body, class Fields>
+template<class Version, class BodyArg, class>
+message<isRequest, Body, Fields>::
+message(verb method, string_view target,
+        Version version, BodyArg&& body_arg)
+    : header_type(method, target, version)
+    , body(std::forward<BodyArg>(body_arg))
+{
+}
+
+template<bool isRequest, class Body, class Fields>
+template<class Version, class BodyArg, class FieldsArg, class>
+message<isRequest, Body, Fields>::
+message(
+    verb method, string_view target, Version version,
+    BodyArg&& body_arg,
+    FieldsArg&& fields_arg)
+    : header_type(method, target, version,
+        std::forward<FieldsArg>(fields_arg))
+    , body(std::forward<BodyArg>(body_arg))
+{
+}
+
+template<bool isRequest, class Body, class Fields>
+template<class Version, class>
+message<isRequest, Body, Fields>::
+message(status result, Version version)
+    : header_type(result, version)
+{
+}
+
+template<bool isRequest, class Body, class Fields>
+template<class Version, class BodyArg, class>
+message<isRequest, Body, Fields>::
+message(status result, Version version,
+    BodyArg&& body_arg)
+    : header_type(result, version)
+    , body(std::forward<BodyArg>(body_arg))
+{
+}
+
+template<bool isRequest, class Body, class Fields>
+template<class Version, class BodyArg, class FieldsArg, class>
+message<isRequest, Body, Fields>::
+message(status result, Version version,
+    BodyArg&& body_arg, FieldsArg&& fields_arg)
+    : header_type(result, version,
+        std::forward<FieldsArg>(fields_arg))
+    , body(std::forward<BodyArg>(body_arg))
+{
+}
+
+template<bool isRequest, class Body, class Fields>
+message<isRequest, Body, Fields>::
+message(std::piecewise_construct_t)
+{
+}
+
+template<bool isRequest, class Body, class Fields>
+template<class... BodyArgs>
+message<isRequest, Body, Fields>::
+message(std::piecewise_construct_t,
+        std::tuple<BodyArgs...> body_args)
+    : message(std::piecewise_construct,
+        body_args,
+        beast::detail::make_index_sequence<
+            sizeof...(BodyArgs)>{})
+{
+}
+
+template<bool isRequest, class Body, class Fields>
+template<class... BodyArgs, class... FieldsArgs>
+message<isRequest, Body, Fields>::
+message(std::piecewise_construct_t,
+    std::tuple<BodyArgs...> body_args,
+    std::tuple<FieldsArgs...> fields_args)
+    : message(std::piecewise_construct,
+        body_args,
+        fields_args,
+        beast::detail::make_index_sequence<
+            sizeof...(BodyArgs)>{},
+        beast::detail::make_index_sequence<
+            sizeof...(FieldsArgs)>{})
+{
+}
+
+#if 0
 template<bool isRequest, class Body, class Fields>
 template<class BodyArg, class>
 message<isRequest, Body, Fields>::
@@ -223,17 +331,6 @@ message(BodyArg&& body_arg, HeaderArg&& header_arg)
 {
 }
 
-template<bool isRequest, class Body, class Fields>
-template<class... BodyArgs>
-message<isRequest, Body, Fields>::
-message(std::piecewise_construct_t,
-        std::tuple<BodyArgs...> body_args)
-    : message(std::piecewise_construct, body_args,
-        beast::detail::make_index_sequence<
-            sizeof...(BodyArgs)>{})
-{
-}
-
 template<bool isRequest, class Body, class Fields>
 template<class... BodyArgs, class... HeaderArgs>
 message<isRequest, Body, Fields>::
@@ -248,6 +345,7 @@ message(std::piecewise_construct_t,
                         sizeof...(HeaderArgs)>{})
 {
 }
+#endif
 
 template<bool isRequest, class Body, class Fields>
 boost::optional<std::uint64_t>
diff --git a/include/beast/http/message.hpp b/include/beast/http/message.hpp
index ec7692a7..93a39ff3 100644
--- a/include/beast/http/message.hpp
+++ b/include/beast/http/message.hpp
@@ -158,8 +158,8 @@ struct header<true, Fields> : Fields
     void
     target(string_view s);
 
-    // VFALCO Don't move these declarations around,
-    //        otherwise the documentation will be wrong.
+    // VFALCO Don't rearrange these declarations or
+    //        ifdefs, or else the documentation will break.
 
     /** Constructor
 
@@ -168,7 +168,8 @@ struct header<true, Fields> : Fields
 
         @note This constructor participates in overload
         resolution if and only if the first parameter is
-        not convertible to @ref header.
+        not convertible to @ref header, @ref verb, or
+        @ref status.
     */
 #if BEAST_DOXYGEN
     template<class... Args>
@@ -178,9 +179,13 @@ struct header<true, Fields> : Fields
 #else
     template<class Arg1, class... ArgN,
         class = typename std::enable_if<
-            (sizeof...(ArgN) > 0) || ! std::is_convertible<
-                typename std::decay<Arg1>::type,
-                    header>::value>::type>
+            ! std::is_convertible<typename
+                std::decay<Arg1>::type, header>::value &&
+            ! std::is_convertible<typename
+                std::decay<Arg1>::type, verb>::value &&
+            ! std::is_convertible<typename
+                std::decay<Arg1>::type, header>::value
+        >::type>
     explicit
     header(Arg1&& arg1, ArgN&&... argn);
 
@@ -193,6 +198,19 @@ private:
     void
     swap(header<true, T>& m1, header<true, T>& m2);
 
+    template<class... FieldsArgs>
+    header(
+        verb method,
+        string_view target_,
+        unsigned version_,
+        FieldsArgs&&... fields_args)
+        : Fields(std::forward<FieldsArgs>(fields_args)...)
+        , version(version_)
+        , method_(method)
+    {
+        target(target_);
+    }
+
     verb method_ = verb::unknown;
 };
 
@@ -207,11 +225,7 @@ struct header<false, Fields> : Fields
         "Fields requirements not met");
 
     /// Indicates if the header is a request or response.
-#if BEAST_DOXYGEN
-    using is_request = std::integral_constant<bool, isRequest>;
-#else
     using is_request = std::false_type;
-#endif
 
     /// The type representing the fields.
     using fields_type = Fields;
@@ -225,7 +239,8 @@ struct header<false, Fields> : Fields
             unsigned minor = version % 10;
         @endcode
 
-        Newly constructed headers will use HTTP/1.1 by default.
+        Newly constructed headers will use HTTP/1.1 by default
+        unless otherwise specified.
     */
     unsigned version = 11;
 
@@ -251,13 +266,16 @@ struct header<false, Fields> : Fields
 
         @note This constructor participates in overload
         resolution if and only if the first parameter is
-        not convertible to @ref header.
+        not convertible to @ref header, @ref verb, or
+        @ref status.
     */
     template<class Arg1, class... ArgN,
         class = typename std::enable_if<
-            (sizeof...(ArgN) > 0) || ! std::is_convertible<
-                typename std::decay<Arg1>::type,
-                    header>::value>::type>
+            ! std::is_convertible<typename
+                std::decay<Arg1>::type, status>::value &&
+            ! std::is_convertible<typename
+                std::decay<Arg1>::type, header>::value
+        >::type>
     explicit
     header(Arg1&& arg1, ArgN&&... argn);
 #endif
@@ -347,6 +365,17 @@ private:
     void
     swap(header<false, T>& m1, header<false, T>& m2);
 
+    template<class... FieldsArgs>
+    header(
+        status result,
+        unsigned version_,
+        FieldsArgs&&... fields_args)
+        : Fields(std::forward<FieldsArgs>(fields_args)...)
+        , version(version_)
+        , result_(result)
+    {
+    }
+
     status result_ = status::ok;
 #endif
 };
@@ -403,82 +432,184 @@ struct message : header<isRequest, Fields>
     /// A value representing the body.
     typename Body::value_type body;
 
-    /// Default constructor
+    /// Constructor
     message() = default;
 
-    /// Move constructor
+    /// Constructor
     message(message&&) = default;
 
-    /// Copy constructor
+    /// Constructor
     message(message const&) = default;
 
-    /// Move assignment
+    /// Assignment
     message& operator=(message&&) = default;
 
-    /// Copy assignment
+    /// Assignment
     message& operator=(message const&) = default;
 
-    /** Constructor.
+    /** Constructor
 
         @param h The header to move construct from.
 
-        @param args Optional arguments forwarded
-        to the body constructor.
+        @param body_args Optional arguments forwarded
+        to the `body` constructor.
     */
-    template<class... Args>
+    template<class... BodyArgs>
     explicit
-    message(header_type&& h, Args&&... args);
+    message(header_type&& h, BodyArgs&&... body_args);
 
     /** Constructor.
 
         @param h The header to copy construct from.
 
-        @param args Optional arguments forwarded
-        to the body constructor.
+        @param body_args Optional arguments forwarded
+        to the `body` constructor.
     */
-    template<class... Args>
+    template<class... BodyArgs>
     explicit
-    message(header_type const& h, Args&&... args);
+    message(header_type const& h, BodyArgs&&... body_args);
 
-    /** Construct a message.
+    /** Constructor
 
-        @param body_arg An argument forwarded to the body constructor.
+        @param method The request-method to use
 
-        @note This constructor participates in overload resolution
-        only if `body_arg` is not convertible to `header_type`.
+        @param target The request-target.
+
+        @param version The HTTP-version
+
+        @note This function is only available when `isRequest == true`.
     */
-    template<class BodyArg
-#if ! BEAST_DOXYGEN
-        , class = typename std::enable_if<
-            ! std::is_convertible<typename
-                std::decay<BodyArg>::type, header_type>::value>::type
+#if BEAST_DOXYGEN
+    message(verb method, string_view target, unsigned version);
+#else
+    template<class Version,
+        class = typename std::enable_if<isRequest &&
+            std::is_convertible<Version, unsigned>::value>::type>
+    message(verb method, string_view target, Version version);
 #endif
-    >
+
+    /** Constructor
+
+        @param method The request-method to use
+
+        @param target The request-target.
+
+        @param version The HTTP-version
+
+        @param body_arg An argument forwarded to the `body` constructor.
+
+        @note This function is only available when `isRequest == true`.
+    */
+#if BEAST_DOXYGEN
+    template<class BodyArg>
+    message(verb method, string_view target,
+        unsigned version, BodyArg&& body_arg);
+#else
+    template<class Version, class BodyArg,
+        class = typename std::enable_if<isRequest &&
+            std::is_convertible<Version, unsigned>::value>::type>
+    message(verb method, string_view target,
+        Version version, BodyArg&& body_arg);
+#endif
+
+    /** Constructor
+
+        @param method The request-method to use
+
+        @param target The request-target.
+
+        @param version The HTTP-version
+
+        @param body_arg An argument forwarded to the `body` constructor.
+
+        @param fields_arg An argument forwarded to the `Fields` constructor.
+
+        @note This function is only available when `isRequest == true`.
+    */
+#if BEAST_DOXYGEN
+    template<class BodyArg, class FieldsArg>
+    message(verb method, string_view target, unsigned version,
+        BodyArg&& body_arg, FieldsArg&& fields_arg);
+#else
+    template<class Version, class BodyArg, class FieldsArg,
+        class = typename std::enable_if<isRequest &&
+            std::is_convertible<Version, unsigned>::value>::type>
+    message(verb method, string_view target, Version version,
+        BodyArg&& body_arg, FieldsArg&& fields_arg);
+#endif
+
+    /** Constructor
+
+        @param result The status-code for the response
+
+        @param version The HTTP-version
+
+        @note This member is only available when `isRequest == false`.
+    */
+#if BEAST_DOXYGEN
+    message(status result, unsigned version);
+#else
+    template<class Version,
+        class = typename std::enable_if<! isRequest &&
+           std::is_convertible<Version, unsigned>::value>::type>
+    message(status result, Version version);
+#endif
+
+    /** Constructor
+
+        @param result The status-code for the response
+
+        @param version The HTTP-version
+
+        @param body_arg An argument forwarded to the `body` constructor.
+
+        @note This member is only available when `isRequest == false`.
+    */
+#if BEAST_DOXYGEN
+    template<class BodyArg>
+    message(status result, unsigned version, BodyArg&& body_arg);
+#else
+    template<class Version, class BodyArg,
+        class = typename std::enable_if<! isRequest &&
+           std::is_convertible<Version, unsigned>::value>::type>
+    message(status result, Version version, BodyArg&& body_arg);
+#endif
+
+    /** Constructor
+
+        @param result The status-code for the response
+
+        @param version The HTTP-version
+
+        @param body_arg An argument forwarded to the `body` constructor.
+
+        @param fields_arg An argument forwarded to the `Fields` base class constructor.
+
+        @note This member is only available when `isRequest == false`.
+    */
+#if BEAST_DOXYGEN
+    template<class BodyArg, class FieldsArg>
+    message(status result, unsigned version,
+        BodyArg&& body_arg, FieldsArg&& fields_arg);
+#else
+    template<class Version, class BodyArg, class FieldsArg,
+        class = typename std::enable_if<! isRequest &&
+           std::is_convertible<Version, unsigned>::value>::type>
+    message(status result, Version version,
+        BodyArg&& body_arg, FieldsArg&& fields_arg);
+#endif
+
+    /** Constructor
+
+        The header and body are default-constructed.
+    */
     explicit
-    message(BodyArg&& body_arg);
+    message(std::piecewise_construct_t);
 
     /** Construct a message.
 
-        @param body_arg An argument forwarded to the body constructor.
-
-        @param header_arg An argument forwarded to the header constructor.
-
-        @note This constructor participates in overload resolution
-        only if `body_arg` is not convertible to `header_type`.
-    */
-    template<class BodyArg, class HeaderArg
-#if ! BEAST_DOXYGEN
-        ,class = typename std::enable_if<
-            ! std::is_convertible<
-                typename std::decay<BodyArg>::type,
-                    header_type>::value>::type
-#endif
-    >
-    message(BodyArg&& body_arg, HeaderArg&& header_arg);
-
-    /** Construct a message.
-
-        @param body_args A tuple forwarded as a parameter pack to the body constructor.
+        @param body_args A tuple forwarded as a parameter
+        pack to the body constructor.
     */
     template<class... BodyArgs>
     message(std::piecewise_construct_t,
@@ -486,14 +617,16 @@ struct message : header<isRequest, Fields>
 
     /** Construct a message.
 
-        @param body_args A tuple forwarded as a parameter pack to the body constructor.
+        @param body_args A tuple forwarded as a parameter
+        pack to the body constructor.
 
-        @param header_args A tuple forwarded as a parameter pack to the fields constructor.
+        @param fields_args A tuple forwarded as a parameter
+        pack to the `Fields` constructor.
     */
-    template<class... BodyArgs, class... HeaderArgs>
+    template<class... BodyArgs, class... FieldsArgs>
     message(std::piecewise_construct_t,
-        std::tuple<BodyArgs...>&& body_args,
-            std::tuple<HeaderArgs...>&& header_args);
+        std::tuple<BodyArgs...> body_args,
+        std::tuple<FieldsArgs...> fields_args);
 
     /// Returns the header portion of the message
     header_type const&
@@ -524,7 +657,6 @@ struct message : header<isRequest, Fields>
     boost::optional<std::uint64_t>
     payload_size() const;
 
-
     /** Prepare the message payload fields for the body.
 
         This function will adjust the Content-Length and
@@ -533,10 +665,7 @@ struct message : header<isRequest, Fields>
 
         @par Example
         @code
-        request<string_body> req;
-        req.version = 11;
-        req.method(verb::upgrade);
-        req.target("/");
+        request<string_body> req{verb::post, "/"};
         req.set(field::user_agent, "Beast");
         req.body = "Hello, world!";
         req.prepare_payload();
diff --git a/test/http/message.cpp b/test/http/message.cpp
index d9469755..b4aa8ac5 100644
--- a/test/http/message.cpp
+++ b/test/http/message.cpp
@@ -8,6 +8,7 @@
 // Test that header file is self-contained.
 #include <beast/http/message.hpp>
 
+#include <beast/http/empty_body.hpp>
 #include <beast/http/string_body.hpp>
 #include <beast/http/fields.hpp>
 #include <beast/http/string_body.hpp>
@@ -70,62 +71,78 @@ public:
         };
     };
 
+    // 0-arg
+    BOOST_STATIC_ASSERT(std::is_constructible<
+        request<default_body>>::value);
+
+    // 1-arg
+    BOOST_STATIC_ASSERT(! std::is_constructible<request<one_arg_body>
+        >::value);
+
+    //BOOST_STATIC_ASSERT(! std::is_constructible<request<one_arg_body>,
+    //    verb, string_view, unsigned>::value);
+
+    BOOST_STATIC_ASSERT(std::is_constructible<request<one_arg_body>,
+        verb, string_view, unsigned, Arg1>::value);
+
+    BOOST_STATIC_ASSERT(std::is_constructible<request<one_arg_body>,
+        verb, string_view, unsigned, Arg1&&>::value);
+
+    BOOST_STATIC_ASSERT(std::is_constructible<request<one_arg_body>,
+        verb, string_view, unsigned, Arg1 const>::value);
+
+    BOOST_STATIC_ASSERT(std::is_constructible<request<one_arg_body>,
+        verb, string_view, unsigned, Arg1 const&>::value);
+
+    // 1-arg + fields
+    BOOST_STATIC_ASSERT(std::is_constructible<request<one_arg_body>,
+        verb, string_view, unsigned, Arg1, fields::allocator_type>::value);
+
+    BOOST_STATIC_ASSERT(std::is_constructible<request<one_arg_body>, std::piecewise_construct_t,
+            std::tuple<Arg1>>::value);
+
+    BOOST_STATIC_ASSERT(std::is_constructible<request<two_arg_body>, std::piecewise_construct_t,
+            std::tuple<Arg1, Arg2>>::value);
+
+    BOOST_STATIC_ASSERT(std::is_constructible<request<two_arg_body>, std::piecewise_construct_t,
+            std::tuple<Arg1, Arg2>, std::tuple<fields::allocator_type>>::value);
+
+    // special members
+    BOOST_STATIC_ASSERT(std::is_copy_constructible<header<true>>::value);
+    BOOST_STATIC_ASSERT(std::is_move_constructible<header<true>>::value);
+    BOOST_STATIC_ASSERT(std::is_copy_assignable<header<true>>::value);
+    BOOST_STATIC_ASSERT(std::is_move_assignable<header<true>>::value);
+    BOOST_STATIC_ASSERT(std::is_copy_constructible<header<false>>::value);
+    BOOST_STATIC_ASSERT(std::is_move_constructible<header<false>>::value);
+    BOOST_STATIC_ASSERT(std::is_copy_assignable<header<false>>::value);
+    BOOST_STATIC_ASSERT(std::is_move_assignable<header<false>>::value);
+
     void
     testMessage()
     {
-        BOOST_STATIC_ASSERT(std::is_constructible<
-            request<default_body>>::value);
-
-        BOOST_STATIC_ASSERT(std::is_constructible<
-            request<one_arg_body>, Arg1>::value);
-
-        BOOST_STATIC_ASSERT(std::is_constructible<
-            request<one_arg_body>, Arg1 const>::value);
-
-        BOOST_STATIC_ASSERT(std::is_constructible<
-            request<one_arg_body>, Arg1 const&>::value);
-
-        BOOST_STATIC_ASSERT(std::is_constructible<
-            request<one_arg_body>, Arg1&&>::value);
-
-        BOOST_STATIC_ASSERT(! std::is_constructible<
-            request<one_arg_body>>::value);
-
-        BOOST_STATIC_ASSERT(std::is_constructible<
-            request<one_arg_body>,
-                Arg1, fields::allocator_type>::value);
-
-        BOOST_STATIC_ASSERT(std::is_constructible<
-            request<one_arg_body>, std::piecewise_construct_t,
-                std::tuple<Arg1>>::value);
-
-        BOOST_STATIC_ASSERT(std::is_constructible<
-            request<two_arg_body>, std::piecewise_construct_t,
-                std::tuple<Arg1, Arg2>>::value);
-
-        BOOST_STATIC_ASSERT(std::is_constructible<
-            request<two_arg_body>, std::piecewise_construct_t,
-                std::tuple<Arg1, Arg2>, std::tuple<fields::allocator_type>>::value);
-
         {
             Arg1 arg1;
-            request<one_arg_body>{std::move(arg1)};
+            request<one_arg_body>{verb::get, "/", 11, std::move(arg1)};
             BEAST_EXPECT(arg1.moved);
         }
 
         {
             header<true> h;
-            h.insert(field::user_agent, "test");
-            request<one_arg_body> m{Arg1{}, h};
-            BEAST_EXPECT(h["User-Agent"] == "test");
-            BEAST_EXPECT(m["User-Agent"] == "test");
+            h.set(field::user_agent, "test");
+            BEAST_EXPECT(h[field::user_agent] == "test");
+            request<default_body> m{std::move(h)};
+            BEAST_EXPECT(m[field::user_agent] == "test");
+            BEAST_EXPECT(h.count(field::user_agent) == 0);
         }
         {
-            header<true> h;
-            h.insert(field::user_agent, "test");
-            request<one_arg_body> m{Arg1{}, std::move(h)};
-            BEAST_EXPECT(! h.count(http::field::user_agent));
+            request<empty_body> h{verb::get, "/", 10};
+            h.set(field::user_agent, "test");
+            request<one_arg_body> m{std::move(h.base()), Arg1{}};
             BEAST_EXPECT(m["User-Agent"] == "test");
+            BEAST_EXPECT(h.count(http::field::user_agent) == 0);
+            BEAST_EXPECT(m.method() == verb::get);
+            BEAST_EXPECT(m.target() == "/");
+            BEAST_EXPECT(m.version == 10);
         }
 
         // swap
@@ -166,31 +183,79 @@ public:
         }
     };
 
+    struct token {};
+
+    struct test_fields
+    {
+        std::string target;
+
+        test_fields() = delete;
+        test_fields(token) {}
+        void set_method_impl(string_view) {}
+        void set_target_impl(string_view s) { target = s.to_string(); }
+        void set_reason_impl(string_view) {}
+        string_view get_method_impl() const { return {}; }
+        string_view get_target_impl() const { return target; }
+        string_view get_reason_impl() const { return {}; }
+        void prepare_payload_impl(bool, boost::optional<std::uint64_t>) {}
+    };
+
     void
-    testHeaders()
+    testMessageCtors()
     {
         {
-            using req_type = header<true>;
-            BOOST_STATIC_ASSERT(std::is_copy_constructible<req_type>::value);
-            BOOST_STATIC_ASSERT(std::is_move_constructible<req_type>::value);
-            BOOST_STATIC_ASSERT(std::is_copy_assignable<req_type>::value);
-            BOOST_STATIC_ASSERT(std::is_move_assignable<req_type>::value);
-
-            using res_type = header<false>;
-            BOOST_STATIC_ASSERT(std::is_copy_constructible<res_type>::value);
-            BOOST_STATIC_ASSERT(std::is_move_constructible<res_type>::value);
-            BOOST_STATIC_ASSERT(std::is_copy_assignable<res_type>::value);
-            BOOST_STATIC_ASSERT(std::is_move_assignable<res_type>::value);
+            request<empty_body> req;
+            BEAST_EXPECT(req.version == 11);
+            BEAST_EXPECT(req.method() == verb::unknown);
+            BEAST_EXPECT(req.target() == "");
         }
-
         {
-            MoveFields h;
-            header<true, MoveFields> r{std::move(h)};
-            BEAST_EXPECT(h.moved_from);
-            BEAST_EXPECT(r.moved_to);
-            request<string_body, MoveFields> m{std::move(r)};
-            BEAST_EXPECT(r.moved_from);
-            BEAST_EXPECT(m.moved_to);
+            request<empty_body> req{verb::get, "/", 11};
+            BEAST_EXPECT(req.version == 11);
+            BEAST_EXPECT(req.method() == verb::get);
+            BEAST_EXPECT(req.target() == "/");
+        }
+        {
+            request<string_body> req{verb::get, "/", 11, "Hello"};
+            BEAST_EXPECT(req.version == 11);
+            BEAST_EXPECT(req.method() == verb::get);
+            BEAST_EXPECT(req.target() == "/");
+            BEAST_EXPECT(req.body == "Hello");
+        }
+        {
+            request<string_body, test_fields> req{
+                verb::get, "/", 11, "Hello", token{}};
+            BEAST_EXPECT(req.version == 11);
+            BEAST_EXPECT(req.method() == verb::get);
+            BEAST_EXPECT(req.target() == "/");
+            BEAST_EXPECT(req.body == "Hello");
+        }
+        {
+            response<string_body> res;
+            BEAST_EXPECT(res.version == 11);
+            BEAST_EXPECT(res.result() == status::ok);
+            BEAST_EXPECT(res.reason() == "OK");
+        }
+        {
+            response<string_body> res{status::bad_request, 10};
+            BEAST_EXPECT(res.version == 10);
+            BEAST_EXPECT(res.result() == status::bad_request);
+            BEAST_EXPECT(res.reason() == "Bad Request");
+        }
+        {
+            response<string_body> res{status::bad_request, 10, "Hello"};
+            BEAST_EXPECT(res.version == 10);
+            BEAST_EXPECT(res.result() == status::bad_request);
+            BEAST_EXPECT(res.reason() == "Bad Request");
+            BEAST_EXPECT(res.body == "Hello");
+        }
+        {
+            response<string_body, test_fields> res{
+                status::bad_request, 10, "Hello", token{}};
+            BEAST_EXPECT(res.version == 10);
+            BEAST_EXPECT(res.result() == status::bad_request);
+            BEAST_EXPECT(res.reason() == "Bad Request");
+            BEAST_EXPECT(res.body == "Hello");
         }
     }
 
@@ -292,7 +357,7 @@ public:
     run() override
     {
         testMessage();
-        testHeaders();
+        testMessageCtors();
         testSwap();
         testSpecialMembers();
         testMethod();
diff --git a/test/http/string_view_body.cpp b/test/http/string_view_body.cpp
index f709a8b9..e6a00a7f 100644
--- a/test/http/string_view_body.cpp
+++ b/test/http/string_view_body.cpp
@@ -27,10 +27,11 @@ public:
     {
         static_assert(is_body_reader<string_view_body>::value, "");
         static_assert(! is_body_writer<string_view_body>::value, "");
-        request<string_view_body> req{"Hello, world!"};
+        request<string_view_body> req;
         req.version = 11;
         req.method(verb::post);
         req.target("/");
+        req.body = "Hello, world!";
         req.prepare_payload();
         static_buffer_n<512> b;
         ostream(b) << req;
diff --git a/test/http/write.cpp b/test/http/write.cpp
index c36352b4..9d494014 100644
--- a/test/http/write.cpp
+++ b/test/http/write.cpp
@@ -278,9 +278,8 @@ public:
             response<string_body> m;
             m.version = 10;
             m.result(status::ok);
-            m.reason("OK");
-            m.insert(field::server, "test");
-            m.insert("Content-Length", "5");
+            m.set(field::server, "test");
+            m.set(field::content_length, "5");
             m.body = "*****";
             error_code ec;
             test::string_ostream ss{ios_};
@@ -297,9 +296,8 @@ public:
             response<string_body> m;
             m.version = 11;
             m.result(status::ok);
-            m.reason("OK");
-            m.insert(field::server, "test");
-            m.insert("Transfer-Encoding", "chunked");
+            m.set(field::server, "test");
+            m.set(field::transfer_encoding, "chunked");
             m.body = "*****";
             error_code ec;
             test::string_ostream ss(ios_);
@@ -327,11 +325,8 @@ public:
             test::fail_counter fc(n);
             test::fail_stream<
                 test::string_ostream> fs(fc, ios_);
-            request<fail_body> m{fc};
-            m.method(verb::get);
-            m.target("/");
-            m.version = 10;
-            m.insert(field::user_agent, "test");
+            request<fail_body> m(verb::get, "/", 10, fc);
+            m.set(field::user_agent, "test");
             m.set(field::connection, "keep-alive");
             m.set(field::content_length, "5");
             m.body = "*****";
@@ -360,12 +355,9 @@ public:
             test::fail_counter fc(n);
             test::fail_stream<
                 test::string_ostream> fs(fc, ios_);
-            request<fail_body> m{fc};
-            m.method(verb::get);
-            m.target("/");
-            m.version = 10;
-            m.insert(field::user_agent, "test");
-            m.insert("Transfer-Encoding", "chunked");
+            request<fail_body> m{verb::get, "/", 10, fc};
+            m.set(field::user_agent, "test");
+            m.set(field::transfer_encoding, "chunked");
             m.body = "*****";
             error_code ec = test::error::fail_error;
             write(fs, m, ec);
@@ -393,12 +385,9 @@ public:
             test::fail_counter fc(n);
             test::fail_stream<
                 test::string_ostream> fs(fc, ios_);
-            request<fail_body> m{fc};
-            m.method(verb::get);
-            m.target("/");
-            m.version = 10;
-            m.insert(field::user_agent, "test");
-            m.insert("Transfer-Encoding", "chunked");
+            request<fail_body> m{verb::get, "/", 10, fc};
+            m.set(field::user_agent, "test");
+            m.set(field::transfer_encoding, "chunked");
             m.body = "*****";
             error_code ec = test::error::fail_error;
             async_write(fs, m, do_yield[ec]);
@@ -426,11 +415,8 @@ public:
             test::fail_counter fc(n);
             test::fail_stream<
                 test::string_ostream> fs(fc, ios_);
-            request<fail_body> m{fc};
-            m.method(verb::get);
-            m.target("/");
-            m.version = 10;
-            m.insert(field::user_agent, "test");
+            request<fail_body> m{verb::get, "/", 10, fc};
+            m.set(field::user_agent, "test");
             m.set(field::connection, "keep-alive");
             m.set(field::content_length, "5");
             m.body = "*****";
@@ -456,11 +442,8 @@ public:
             test::fail_counter fc(n);
             test::fail_stream<
                 test::string_ostream> fs(fc, ios_);
-            request<fail_body> m{fc};
-            m.method(verb::get);
-            m.target("/");
-            m.version = 10;
-            m.insert(field::user_agent, "test");
+            request<fail_body> m{verb::get, "/", 10, fc};
+            m.set(field::user_agent, "test");
             m.set(field::connection, "keep-alive");
             m.set(field::content_length, "5");
             m.body = "*****";
@@ -491,7 +474,7 @@ public:
             m.method(verb::get);
             m.target("/");
             m.version = 10;
-            m.insert(field::user_agent, "test");
+            m.set(field::user_agent, "test");
             m.body = "*";
             m.prepare_payload();
             BEAST_EXPECT(str(m) ==
@@ -508,7 +491,7 @@ public:
             m.method(verb::get);
             m.target("/");
             m.version = 10;
-            m.insert(field::user_agent, "test");
+            m.set(field::user_agent, "test");
             m.body = "*";
             m.prepare_payload();
             test::string_ostream ss(ios_);
@@ -528,7 +511,7 @@ public:
             m.method(verb::get);
             m.target("/");
             m.version = 11;
-            m.insert(field::user_agent, "test");
+            m.set(field::user_agent, "test");
             m.body = "*";
             m.prepare_payload();
             BEAST_EXPECT(str(m) ==
@@ -545,7 +528,7 @@ public:
             m.method(verb::get);
             m.target("/");
             m.version = 11;
-            m.insert(field::user_agent, "test");
+            m.set(field::user_agent, "test");
             m.body = "*";
             m.prepare_payload();
             test::string_ostream ss(ios_);
@@ -570,7 +553,7 @@ public:
         m.method(verb::get);
         m.target("/");
         m.version = 11;
-        m.insert(field::user_agent, "test");
+        m.set(field::user_agent, "test");
         m.body = "*";
         BEAST_EXPECT(boost::lexical_cast<std::string>(m) ==
             "GET / HTTP/1.1\r\nUser-Agent: test\r\n\r\n*");
@@ -600,7 +583,7 @@ public:
             m.method(verb::get);
             m.version = 11;
             m.target("/");
-            m.insert("Content-Length", 5);
+            m.set("Content-Length", 5);
             m.body = "*****";
             async_write(os, m, handler{});
             BEAST_EXPECT(handler::count() > 0);
@@ -622,7 +605,7 @@ public:
                 m.method(verb::get);
                 m.version = 11;
                 m.target("/");
-                m.insert("Content-Length", 5);
+                m.set("Content-Length", 5);
                 m.body = "*****";
                 async_write(is, m, handler{});
                 BEAST_EXPECT(handler::count() > 0);
@@ -704,7 +687,7 @@ public:
         m0.version = 11;
         m0.result(status::ok);
         m0.reason("OK");
-        m0.insert(field::server, "test");
+        m0.set(field::server, "test");
         m0.body.s = "Hello, world!\n";
 
         {
@@ -761,7 +744,7 @@ public:
             }
         }
         {
-            m0.insert("Transfer-Encoding", "chunked");
+            m0.set("Transfer-Encoding", "chunked");
             {
                 auto m = m0;
                 error_code ec;