Add post parse rpc validation to rpc::body template.

include/bitcoin/network/protocols/protocol_http.hpp

@@ -79,6 +79,7 @@ class BCT_API protocol_http
     /// Senders.
     virtual void send_ok(const http::request& request={}) NOEXCEPT;
     virtual void send_bad_host(const http::request& request={}) NOEXCEPT;
+    virtual void send_bad_request(const http::request& request={}) NOEXCEPT;
     virtual void send_not_found(const http::request& request={}) NOEXCEPT;
     virtual void send_not_acceptable(const http::request& request={}) NOEXCEPT;
     virtual void send_forbidden(const http::request& request={}) NOEXCEPT;

src/messages/rpc_body.cpp

@@ -20,6 +20,7 @@
 
 #include <memory>
 #include <utility>
+#include <variant>
 #include <bitcoin/network/define.hpp>
 #include <bitcoin/network/messages/messages.hpp>
 #include <bitcoin/network/rpc/rpc.hpp>
@@ -119,6 +120,31 @@ finish(boost_code& ec) NOEXCEPT
         // As a catch-all we blame alloc.
         ec = to_http_code(http_error_t::bad_alloc);
     }
+
+    // Post-parse semantic validation.
+
+    if (value_.message.jsonrpc == version::undefined)
+        value_.message.jsonrpc = version::v1;
+
+    if (value_.message.method.empty() ||
+        !value_.message.params.has_value())
+    {
+        ec = to_boost_code(boost_error_t::bad_message);
+        return;
+    }
+
+    if (value_.message.jsonrpc == version::v1)
+    {
+        if (!value_.message.id.has_value())
+            ec = to_boost_code(boost_error_t::bad_message);
+        else if (!std::holds_alternative<array_t>(
+            value_.message.params.value()))
+            ec = to_boost_code(boost_error_t::bad_message);
+
+        // TODO: v1 batch is not allowed.
+        ////else if (value_.message.is_batch())
+        ////    ec = to_boost_code(boost_error_t::bad_message);
+    }
 }
 
 template <>

src/protocols/protocol_http.cpp

@@ -245,6 +245,19 @@ void protocol_http::send_forbidden(const request& request) NOEXCEPT
     SEND(std::move(out), handle_complete, _1, error::forbidden);
 }
 
+// Closes channel.
+void protocol_http::send_bad_request(const request& request) NOEXCEPT
+{
+    BC_ASSERT(stranded());
+    const auto code = status::bad_request;
+    const auto media = to_media_type(request[field::accept]);
+    response out{ code, request.version() };
+    add_common_headers(out, request, true);
+    out.body() = string_status(code, out.reason(), media);
+    out.prepare_payload();
+    SEND(std::move(out), handle_complete, _1, error::bad_request);
+}
+
 // Closes channel.
 void protocol_http::send_bad_host(const request& request) NOEXCEPT
 {

src/rpc/model.cpp

@@ -299,18 +299,26 @@ DEFINE_JSON_FROM_TAG(response_t)
     {
         const auto& result = instance.error.value();
 
-        object["error"] =
-        {
-            { "code", result.code },
-            { "message", result.message }
-        };
-
         if (result.data.has_value())
         {
-            object["data"] = value_from(result.data.value());
+            object["error"] =
+            {
+                { "code", result.code },
+                { "message", result.message },
+                { "data", value_from(result.data.value()) }
+            };
+        }
+        else
+        {
+            object["error"] =
+            {
+                { "code", result.code },
+                { "message", result.message }
+            };
         }
     }
-    else if (instance.jsonrpc != version::v2)
+    else if (instance.jsonrpc == version::v1 || 
+        instance.jsonrpc == version::undefined)
     {
         object["error"] = boost::json::value{};
     }
@@ -319,6 +327,11 @@ DEFINE_JSON_FROM_TAG(response_t)
     {
         object["result"] = value_from(instance.result.value());
     }
+    else if (instance.jsonrpc == version::v1 ||
+        instance.jsonrpc == version::undefined)
+    {
+        object["result"] = boost::json::value{};
+    }
 
     value = object;
 }