message::prepare_payload replaces message::prepare (API Change):

Actions Required:

* Change calls to msg.prepare to msg.prepare_payload. For messages
  with a user-defined Fields, provide the function prepare_payload_impl
  in the fields type according to the Fields requirements.

test/http/doc_examples.cpp

@@ -73,7 +73,7 @@ public:
                 req.target("/");
                 req.insert(field::user_agent, "test");
                 req.body = "Hello, world!";
-                req.prepare();
+                req.prepare_payload();
 
                 error_code ec;
                 send_expect_100_continue(
@@ -106,7 +106,7 @@ public:
         req.target("/");
         req.insert(field::user_agent, "test");
         req.body = "Hello, world!";
-        req.prepare();
+        req.prepare_payload();
 
         test::pipe downstream{ios_};
         downstream.server.read_size(3);
@@ -272,7 +272,7 @@ public:
             req.method(verb::put);
             req.target("/");
             req.body = body;
-            req.prepare();
+            req.prepare_payload();
             write(c.client, req);
         }
         {
@@ -293,7 +293,7 @@ public:
             res.result(status::ok);
             res.insert(field::server, "test");
             res.body = path;
-            res.prepare();
+            res.prepare_payload();
             write(c.server, res);
         }
         {

test/http/doc_snippets.cpp

@@ -49,7 +49,7 @@ void fxx() {
     res.result(status::ok);
     res.set(field::server, "Beast");
     res.body = "Hello, world!";
-    res.prepare();
+    res.prepare_payload();
 
 //]
 }

test/http/fields.cpp

@@ -8,6 +8,8 @@
 // Test that header file is self-contained.
 #include <beast/http/fields.hpp>
 
+#include <beast/http/empty_body.hpp>
+#include <beast/http/message.hpp>
 #include <beast/test/test_allocator.hpp>
 #include <beast/unit_test/suite.hpp>
 #include <boost/lexical_cast.hpp>
@@ -397,6 +399,188 @@ public:
         }
     }
 
+    struct sized_body
+    {
+        using value_type = std::uint64_t;
+
+        static
+        std::uint64_t
+        size(value_type const& v)
+        {
+            return v;
+        }
+    };
+
+    struct unsized_body
+    {
+        struct value_type {};
+    };
+
+    void
+    testPreparePayload()
+    {
+        // GET, empty
+        {
+            request<empty_body> req;
+            req.version = 11;
+            req.method(verb::get);
+
+            req.prepare_payload();
+            BEAST_EXPECT(req.count(field::content_length) == 0);
+            BEAST_EXPECT(req.count(field::transfer_encoding) == 0);
+
+            req.set(field::content_length, "0");
+            req.set(field::transfer_encoding, "chunked");
+            req.prepare_payload();
+
+            BEAST_EXPECT(req.count(field::content_length) == 0);
+            BEAST_EXPECT(req.count(field::transfer_encoding) == 0);
+
+            req.set(field::transfer_encoding, "deflate");
+            req.prepare_payload();
+            BEAST_EXPECT(req.count(field::content_length) == 0);
+            BEAST_EXPECT(req[field::transfer_encoding] == "deflate");
+
+            req.set(field::transfer_encoding, "deflate, chunked");
+            req.prepare_payload();
+            BEAST_EXPECT(req.count(field::content_length) == 0);
+            BEAST_EXPECT(req[field::transfer_encoding] == "deflate");
+        }
+
+        // GET, sized
+        {
+            request<sized_body> req;
+            req.version = 11;
+            req.method(verb::get);
+            req.body = 50;
+
+            req.prepare_payload();
+            BEAST_EXPECT(req[field::content_length] == "50");
+            BEAST_EXPECT(req[field::transfer_encoding] == "");
+
+            req.set(field::content_length, "0");
+            req.set(field::transfer_encoding, "chunked");
+            req.prepare_payload();
+            BEAST_EXPECT(req[field::content_length] == "50");
+            BEAST_EXPECT(req.count(field::transfer_encoding) == 0);
+
+            req.set(field::transfer_encoding, "deflate, chunked");
+            req.prepare_payload();
+            BEAST_EXPECT(req[field::content_length] == "50");
+            BEAST_EXPECT(req[field::transfer_encoding] == "deflate");
+        }
+
+        // PUT, empty
+        {
+            request<empty_body> req;
+            req.version = 11;
+            req.method(verb::put);
+
+            req.prepare_payload();
+            BEAST_EXPECT(req[field::content_length] == "0");
+            BEAST_EXPECT(req.count(field::transfer_encoding) == 0);
+
+            req.set(field::content_length, "50");
+            req.set(field::transfer_encoding, "deflate, chunked");
+            req.prepare_payload();
+            BEAST_EXPECT(req[field::content_length] == "0");
+            BEAST_EXPECT(req[field::transfer_encoding] == "deflate");
+        }
+
+        // PUT, sized
+        {
+            request<sized_body> req;
+            req.version = 11;
+            req.method(verb::put);
+            req.body = 50;
+
+            req.prepare_payload();
+            BEAST_EXPECT(req[field::content_length] == "50");
+            BEAST_EXPECT(req.count(field::transfer_encoding) == 0);
+
+            req.set(field::content_length, "25");
+            req.set(field::transfer_encoding, "deflate, chunked");
+            req.prepare_payload();
+            BEAST_EXPECT(req[field::content_length] == "50");
+            BEAST_EXPECT(req[field::transfer_encoding] == "deflate");
+        }
+
+        // POST, unsized
+        {
+            request<unsized_body> req;
+            req.version = 11;
+            req.method(verb::post);
+
+            req.prepare_payload();
+            BEAST_EXPECT(req.count(field::content_length) == 0);
+            BEAST_EXPECT(req[field::transfer_encoding] == "chunked");
+
+            req.set(field::transfer_encoding, "deflate");
+            req.prepare_payload();
+            BEAST_EXPECT(req.count(field::content_length) == 0);
+            BEAST_EXPECT(req[field::transfer_encoding] == "deflate, chunked");
+        }
+
+        // POST, unsized HTTP/1.0
+        {
+            request<unsized_body> req;
+            req.version = 10;
+            req.method(verb::post);
+
+            req.prepare_payload();
+            BEAST_EXPECT(req.count(field::content_length) == 0);
+            BEAST_EXPECT(req.count(field::transfer_encoding) == 0);
+
+            req.set(field::transfer_encoding, "deflate");
+            req.prepare_payload();
+            BEAST_EXPECT(req.count(field::content_length) == 0);
+            BEAST_EXPECT(req[field::transfer_encoding] == "deflate");
+        }
+
+        // OK, empty
+        {
+            response<empty_body> res;
+            res.version = 11;
+
+            res.prepare_payload();
+            BEAST_EXPECT(res[field::content_length] == "0");
+            BEAST_EXPECT(res.count(field::transfer_encoding) == 0);
+
+            res.erase(field::content_length);
+            res.set(field::transfer_encoding, "chunked");
+            res.prepare_payload();
+            BEAST_EXPECT(res[field::content_length] == "0");
+            BEAST_EXPECT(res.count(field::transfer_encoding) == 0);
+        }
+
+        // OK, sized
+        {
+            response<sized_body> res;
+            res.version = 11;
+            res.body = 50;
+
+            res.prepare_payload();
+            BEAST_EXPECT(res[field::content_length] == "50");
+            BEAST_EXPECT(res.count(field::transfer_encoding) == 0);
+
+            res.erase(field::content_length);
+            res.set(field::transfer_encoding, "chunked");
+            res.prepare_payload();
+            BEAST_EXPECT(res[field::content_length] == "50");
+            BEAST_EXPECT(res.count(field::transfer_encoding) == 0);
+        }
+
+        // OK, unsized
+        {
+            response<unsized_body> res;
+            res.version = 11;
+
+            res.prepare_payload();
+            BEAST_EXPECT(res.count(field::content_length) == 0);
+            BEAST_EXPECT(res[field::transfer_encoding] == "chunked");
+        }
+    }
+
     void run() override
     {
         testMembers();
@@ -404,6 +588,7 @@ public:
         testRFC2616();
         testErase();
         testContainer();
+        testPreparePayload();
     }
 };
 

test/http/string_view_body.cpp

@@ -31,7 +31,7 @@ public:
         req.version = 11;
         req.method(verb::post);
         req.target("/");
-        req.prepare();
+        req.prepare_payload();
         static_buffer_n<512> b;
         ostream(b) << req;
         string_view const s{

test/http/write.cpp

@@ -532,7 +532,7 @@ public:
             m.version = 10;
             m.insert(field::user_agent, "test");
             m.body = "*";
-            m.prepare();
+            m.prepare_payload();
             BEAST_EXPECT(str(m) ==
                 "GET / HTTP/1.0\r\n"
                 "User-Agent: test\r\n"
@@ -549,7 +549,7 @@ public:
             m.version = 10;
             m.insert(field::user_agent, "test");
             m.body = "*";
-            m.prepare();
+            m.prepare_payload();
             test::string_ostream ss(ios_);
             error_code ec;
             write(ss, m, ec);
@@ -569,7 +569,7 @@ public:
             m.version = 11;
             m.insert(field::user_agent, "test");
             m.body = "*";
-            m.prepare();
+            m.prepare_payload();
             BEAST_EXPECT(str(m) ==
                 "GET / HTTP/1.1\r\n"
                 "User-Agent: test\r\n"
@@ -586,7 +586,7 @@ public:
             m.version = 11;
             m.insert(field::user_agent, "test");
             m.body = "*";
-            m.prepare();
+            m.prepare_payload();
             test::string_ostream ss(ios_);
             error_code ec;
             write(ss, m, ec);