Remove middlewares

Middlewares, while kinda cool from an academic standpoint, make our
build times even worse than they already are.  Given that we only really
use 1 real middleware today (token auth) and it needs to move into the
parser mode anyway (for security limiting buffer sizes), we might as well
use this as an opportunity to delete some code.

Some other things that happen:
1. Persistent data now moves out of the crow namespace
2. App is no longer a template
3. All request_routes implementations no longer become templates.  This
should be a decent (unmeasured) win on compile times.

This commit was part of a commit previously called "various cleanups".
This separates ONLY the middleware deletion part of that.

Note, this also deletes about 400 lines of hard to understand code.

Change-Id: I4c19e25491a153a2aa2e4ef46fc797bcb5b3581a
Signed-off-by: Ed Tanous <ed@tanous.net>

1 files changed, 15 insertions, 212 deletions

diff --git a/http/http_connection.h b/http/http_connection.h
index 8dba3d6b59..609d4a10b1 100644
--- a/http/http_connection.h
+++ b/http/http_connection.h
@@ -3,7 +3,6 @@
 
 #include "http_response.h"
 #include "logging.h"
-#include "middleware_context.h"
 #include "timer_queue.h"
 #include "utility.h"
 
@@ -19,6 +18,7 @@
 #include <boost/beast/http.hpp>
 #include <boost/beast/ssl/ssl_stream.hpp>
 #include <boost/beast/websocket.hpp>
+#include <security_headers.hpp>
 #include <ssl_key_handler.hpp>
 
 #include <atomic>
@@ -61,186 +61,6 @@ inline void prettyPrintJson(crow::Response& res)
 using namespace boost;
 using tcp = asio::ip::tcp;
 
-namespace detail
-{
-template <typename MW>
-struct CheckBeforeHandleArity3Const
-{
-    template <typename T,
-              void (T::*)(Request&, Response&, typename MW::Context&) const =
-                  &T::beforeHandle>
-    struct Get
-    {};
-};
-
-template <typename MW>
-struct CheckBeforeHandleArity3
-{
-    template <typename T, void (T::*)(Request&, Response&,
-                                      typename MW::Context&) = &T::beforeHandle>
-    struct Get
-    {};
-};
-
-template <typename MW>
-struct CheckAfterHandleArity3Const
-{
-    template <typename T,
-              void (T::*)(Request&, Response&, typename MW::Context&) const =
-                  &T::afterHandle>
-    struct Get
-    {};
-};
-
-template <typename MW>
-struct CheckAfterHandleArity3
-{
-    template <typename T, void (T::*)(Request&, Response&,
-                                      typename MW::Context&) = &T::afterHandle>
-    struct Get
-    {};
-};
-
-template <typename T>
-struct IsBeforeHandleArity3Impl
-{
-    template <typename C>
-    static std::true_type
-        f(typename CheckBeforeHandleArity3Const<T>::template Get<C>*);
-
-    template <typename C>
-    static std::true_type
-        f(typename CheckBeforeHandleArity3<T>::template Get<C>*);
-
-    template <typename C>
-    static std::false_type f(...);
-
-  public:
-    static constexpr bool value = decltype(f<T>(nullptr))::value;
-};
-
-template <typename T>
-struct IsAfterHandleArity3Impl
-{
-    template <typename C>
-    static std::true_type
-        f(typename CheckAfterHandleArity3Const<T>::template Get<C>*);
-
-    template <typename C>
-    static std::true_type
-        f(typename CheckAfterHandleArity3<T>::template Get<C>*);
-
-    template <typename C>
-    static std::false_type f(...);
-
-  public:
-    static constexpr bool value = decltype(f<T>(nullptr))::value;
-};
-
-template <typename MW, typename Context, typename ParentContext>
-typename std::enable_if<!IsBeforeHandleArity3Impl<MW>::value>::type
-    beforeHandlerCall(MW& mw, Request& req, Response& res, Context& ctx,
-                      ParentContext& /*parent_ctx*/)
-{
-    mw.beforeHandle(req, res, ctx.template get<MW>(), ctx);
-}
-
-template <typename MW, typename Context, typename ParentContext>
-typename std::enable_if<IsBeforeHandleArity3Impl<MW>::value>::type
-    beforeHandlerCall(MW& mw, Request& req, Response& res, Context& ctx,
-                      ParentContext& /*parent_ctx*/)
-{
-    mw.beforeHandle(req, res, ctx.template get<MW>());
-}
-
-template <typename MW, typename Context, typename ParentContext>
-typename std::enable_if<!IsAfterHandleArity3Impl<MW>::value>::type
-    afterHandlerCall(MW& mw, Request& req, Response& res, Context& ctx,
-                     ParentContext& /*parent_ctx*/)
-{
-    mw.afterHandle(req, res, ctx.template get<MW>(), ctx);
-}
-
-template <typename MW, typename Context, typename ParentContext>
-typename std::enable_if<IsAfterHandleArity3Impl<MW>::value>::type
-    afterHandlerCall(MW& mw, Request& req, Response& res, Context& ctx,
-                     ParentContext& /*parent_ctx*/)
-{
-    mw.afterHandle(req, res, ctx.template get<MW>());
-}
-
-template <size_t N, typename Context, typename Container, typename CurrentMW,
-          typename... Middlewares>
-bool middlewareCallHelper(Container& middlewares, Request& req, Response& res,
-                          Context& ctx)
-{
-    using parent_context_t = typename Context::template partial<N - 1>;
-    beforeHandlerCall<CurrentMW, Context, parent_context_t>(
-        std::get<N>(middlewares), req, res, ctx,
-        static_cast<parent_context_t&>(ctx));
-
-    if (res.isCompleted())
-    {
-        afterHandlerCall<CurrentMW, Context, parent_context_t>(
-            std::get<N>(middlewares), req, res, ctx,
-            static_cast<parent_context_t&>(ctx));
-        return true;
-    }
-
-    if (middlewareCallHelper<N + 1, Context, Container, Middlewares...>(
-            middlewares, req, res, ctx))
-    {
-        afterHandlerCall<CurrentMW, Context, parent_context_t>(
-            std::get<N>(middlewares), req, res, ctx,
-            static_cast<parent_context_t&>(ctx));
-        return true;
-    }
-
-    return false;
-}
-
-template <size_t N, typename Context, typename Container>
-bool middlewareCallHelper(Container& /*middlewares*/, Request& /*req*/,
-                          Response& /*res*/, Context& /*ctx*/)
-{
-    return false;
-}
-
-template <size_t N, typename Context, typename Container>
-typename std::enable_if<(N < 0)>::type
-    afterHandlersCallHelper(Container& /*middlewares*/, Context& /*Context*/,
-                            Request& /*req*/, Response& /*res*/)
-{}
-
-template <size_t N, typename Context, typename Container>
-typename std::enable_if<(N == 0)>::type
-    afterHandlersCallHelper(Container& middlewares, Context& ctx, Request& req,
-                            Response& res)
-{
-    using parent_context_t = typename Context::template partial<N - 1>;
-    using CurrentMW = typename std::tuple_element<
-        N, typename std::remove_reference<Container>::type>::type;
-    afterHandlerCall<CurrentMW, Context, parent_context_t>(
-        std::get<N>(middlewares), req, res, ctx,
-        static_cast<parent_context_t&>(ctx));
-}
-
-template <size_t N, typename Context, typename Container>
-typename std::enable_if<(N > 0)>::type
-    afterHandlersCallHelper(Container& middlewares, Context& ctx, Request& req,
-                            Response& res)
-{
-    using parent_context_t = typename Context::template partial<N - 1>;
-    using CurrentMW = typename std::tuple_element<
-        N, typename std::remove_reference<Container>::type>::type;
-    afterHandlerCall<CurrentMW, Context, parent_context_t>(
-        std::get<N>(middlewares), req, res, ctx,
-        static_cast<parent_context_t&>(ctx));
-    afterHandlersCallHelper<N - 1, Context, Container>(middlewares, ctx, req,
-                                                       res);
-}
-} // namespace detail
-
 #ifdef BMCWEB_ENABLE_DEBUG
 static std::atomic<int> connectionCount;
 #endif
@@ -261,21 +81,18 @@ static constexpr const size_t loggedInAttempts =
 static constexpr const size_t loggedOutAttempts =
     (15 / timerQueueTimeoutSeconds);
 
-template <typename Adaptor, typename Handler, typename... Middlewares>
+template <typename Adaptor, typename Handler>
 class Connection :
-    public std::enable_shared_from_this<
-        Connection<Adaptor, Handler, Middlewares...>>
+    public std::enable_shared_from_this<Connection<Adaptor, Handler>>
 {
   public:
     Connection(boost::asio::io_context& ioService, Handler* handlerIn,
                const std::string& ServerNameIn,
-               std::tuple<Middlewares...>* middlewaresIn,
                std::function<std::string()>& get_cached_date_str_f,
                detail::TimerQueue& timerQueueIn, Adaptor adaptorIn) :
         adaptor(std::move(adaptorIn)),
         handler(handlerIn), serverName(ServerNameIn),
-        middlewares(middlewaresIn), getCachedDateStr(get_cached_date_str_f),
-        timerQueue(timerQueueIn)
+        getCachedDateStr(get_cached_date_str_f), timerQueue(timerQueueIn)
     {
         parser.emplace(std::piecewise_construct, std::make_tuple());
         parser->body_limit(httpReqBodyLimit);
@@ -285,7 +102,7 @@ class Connection :
 #ifdef BMCWEB_ENABLE_MUTUAL_TLS_AUTHENTICATION
         auto ca_available = !std::filesystem::is_empty(
             std::filesystem::path(ensuressl::trustStorePath));
-        if (ca_available && crow::persistent_data::SessionStore::getInstance()
+        if (ca_available && persistent_data::SessionStore::getInstance()
                                 .getAuthMethodsConfig()
                                 .tls)
         {
@@ -301,7 +118,7 @@ class Connection :
                                         bool preverified,
                                         boost::asio::ssl::verify_context& ctx) {
             // do nothing if TLS is disabled
-            if (!crow::persistent_data::SessionStore::getInstance()
+            if (!persistent_data::SessionStore::getInstance()
                      .getAuthMethodsConfig()
                      .tls)
             {
@@ -444,10 +261,10 @@ class Connection :
             }
             sslUser.resize(lastChar);
 
-            session = persistent_data::SessionStore::getInstance()
-                          .generateUserSession(
-                              sslUser,
-                              crow::persistent_data::PersistenceType::TIMEOUT);
+            session =
+                persistent_data::SessionStore::getInstance()
+                    .generateUserSession(
+                        sslUser, persistent_data::PersistenceType::TIMEOUT);
             if (auto sp = session.lock())
             {
                 BMCWEB_LOG_DEBUG << this
@@ -538,15 +355,9 @@ class Connection :
             res.completeRequestHandler = [] {};
             res.isAliveHelper = [this]() -> bool { return isAlive(); };
 
-            ctx = detail::Context<Middlewares...>();
-            req->middlewareContext = static_cast<void*>(&ctx);
             req->ioService = static_cast<decltype(req->ioService)>(
                 &adaptor.get_executor().context());
 
-            detail::middlewareCallHelper<
-                0U, decltype(ctx), decltype(*middlewares), Middlewares...>(
-                *middlewares, *req, res, ctx);
-
             if (!res.completed)
             {
                 needToCallAfterHandlers = true;
@@ -618,16 +429,10 @@ class Connection :
         BMCWEB_LOG_INFO << "Response: " << this << ' ' << req->url << ' '
                         << res.resultInt() << " keepalive=" << req->keepAlive();
 
+        addSecurityHeaders(res);
+
         if (needToCallAfterHandlers)
         {
-            needToCallAfterHandlers = false;
-
-            // call all afterHandler of middlewares
-            detail::afterHandlersCallHelper<sizeof...(Middlewares) - 1,
-                                            decltype(ctx),
-                                            decltype(*middlewares)>(
-                *middlewares, ctx, *req, res);
-
             crow::authorization::cleanupTempSession(*req);
         }
 
@@ -949,7 +754,8 @@ class Connection :
 
     std::optional<crow::Request> req;
     crow::Response res;
-    std::weak_ptr<crow::persistent_data::UserSession> session;
+
+    std::weak_ptr<persistent_data::UserSession> session;
 
     const std::string& serverName;
 
@@ -958,13 +764,10 @@ class Connection :
     bool needToCallAfterHandlers{};
     bool needToStartReadAfterComplete{};
 
-    std::tuple<Middlewares...>* middlewares;
-    detail::Context<Middlewares...> ctx;
-
     std::function<std::string()>& getCachedDateStr;
     detail::TimerQueue& timerQueue;
 
     using std::enable_shared_from_this<
-        Connection<Adaptor, Handler, Middlewares...>>::shared_from_this;
+        Connection<Adaptor, Handler>>::shared_from_this;
 };
 } // namespace crow