role_type is in boost/beast/core/role.hpp (API Change):

This enumeration is now part of the library core and
not specific to websocket.

test/beast/core/CMakeLists.txt

@@ -62,6 +62,7 @@ add_executable (tests-beast-core
     ostream.cpp
     rate_policy.cpp
     read_size.cpp
+    role.cpp
     saved_handler.cpp
     span.cpp
     static_buffer.cpp

test/beast/core/Jamfile

@@ -50,6 +50,7 @@ local SOURCES =
     ostream.cpp
     rate_policy.cpp
     read_size.cpp
+    role.cpp
     saved_handler.cpp
     span.cpp
     static_buffer.cpp

test/beast/core/basic_stream.cpp

@@ -1200,13 +1200,13 @@ public:
         {
             error_code ec;
             stream_type s(ioc);
-            teardown(websocket::role_type::client, s, ec);
+            teardown(role_type::client, s, ec);
         }
 
         {
             error_code ec;
             stream_type s(ioc);
-            async_teardown(websocket::role_type::server, s,
+            async_teardown(role_type::server, s,
                 [](error_code)
                 {
                 });

test/beast/core/flat_stream.cpp

@@ -14,7 +14,7 @@
 
 #include <boost/beast/_experimental/unit_test/suite.hpp>
 #include <boost/beast/_experimental/test/stream.hpp>
-#include <boost/beast/websocket/role.hpp>
+#include <boost/beast/core/role.hpp>
 #include <initializer_list>
 #include <vector>
 
@@ -162,14 +162,14 @@ public:
             flat_stream<test::stream> s(ioc);
             ts.connect(s.next_layer());
             error_code ec;
-            teardown(websocket::role_type::client, s, ec);
+            teardown(role_type::client, s, ec);
         }
 
         {
             test::stream ts(ioc);
             flat_stream<test::stream> s(ioc);
             ts.connect(s.next_layer());
-            async_teardown(websocket::role_type::client, s,
+            async_teardown(role_type::client, s,
                 [](error_code)
                 {
                 });

test/beast/core/role.cpp

@@ -0,0 +1,11 @@
+//
+// Copyright (c) 2016-2019 Vinnie Falco (vinnie dot falco at gmail dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+// Official repository: https://github.com/boostorg/beast
+//
+
+// Test that header file is self-contained.
+#include <boost/beast/core/role.hpp>