Change the completionhandler to accept Res

These modifications are from WIP:Redfish:Query parameters:Only
(https://gerrit.openbmc-project.xyz/c/openbmc/bmcweb/+/47474). It will
be used in future CLs for Query Parameters.

The code changed the completion handle to accept Res to be able to
recall handle with a new Response object.
AsyncResp owns a new res, so there is no need to pass in a res.

Also fixed a self-move assignment bug.

Context:
Originally submitted:
https://gerrit.openbmc-project.xyz/c/openbmc/bmcweb/+/480020

Reveted here:
https://gerrit.openbmc-project.xyz/c/openbmc/bmcweb/+/48880

Because of failures here:
https://gerrit.openbmc-project.xyz/c/openbmc/openbmc/+/48864

Tested:
1. Romulus QEMU + Robot tests; all passed
2. Use scripts/websocket_test.py to test websockets. It is still work correctly.
3. Tested in real hardware; no new validator errors; tested both
   authless, session, and basic auth.
4. Hacked codes to return 500 errors on certain resource; response is
   expected;
5. Tested Eventing, the push style one (not SSE which is still under
   review), worked as expected.
6. Tested 404 errors; response is expected.

Signed-off-by: Nan Zhou <nanzhoumails@gmail.com>
Signed-off-by: John Edward Broadbent <jebr@google.com>
Change-Id: I52adb174476e0f6656335baa6657456752a031be

1 files changed, 40 insertions, 14 deletions

diff --git a/http/http_response.hpp b/http/http_response.hpp
index 08b76f2478..3c2a3f98b9 100644
--- a/http/http_response.hpp
+++ b/http/http_response.hpp
@@ -43,15 +43,25 @@ struct Response
 
     Response(const Response&) = delete;
     Response(Response&&) = delete;
+
     Response& operator=(const Response& r) = delete;
 
     Response& operator=(Response&& r) noexcept
     {
-        BMCWEB_LOG_DEBUG << "Moving response containers";
+        BMCWEB_LOG_DEBUG << "Moving response containers; this: " << this
+                         << "; other: " << &r;
+        if (this == &r)
+        {
+            return *this;
+        }
         stringResponse = std::move(r.stringResponse);
         r.stringResponse.emplace(response_type{});
         jsonValue = std::move(r.jsonValue);
         completed = r.completed;
+        completeRequestHandler = std::move(r.completeRequestHandler);
+        isAliveHelper = std::move(r.isAliveHelper);
+        r.completeRequestHandler = nullptr;
+        r.isAliveHelper = nullptr;
         return *this;
     }
 
@@ -117,37 +127,53 @@ struct Response
     {
         if (completed)
         {
-            BMCWEB_LOG_ERROR << "Response was ended twice";
+            BMCWEB_LOG_ERROR << this << " Response was ended twice";
             return;
         }
         completed = true;
-        BMCWEB_LOG_DEBUG << "calling completion handler";
+        BMCWEB_LOG_DEBUG << this << " calling completion handler";
         if (completeRequestHandler)
         {
-            BMCWEB_LOG_DEBUG << "completion handler was valid";
-            completeRequestHandler();
+            BMCWEB_LOG_DEBUG << this << " completion handler was valid";
+            completeRequestHandler(*this);
         }
     }
 
-    void end(std::string_view bodyPart)
+    bool isAlive()
     {
-        write(bodyPart);
-        end();
+        return isAliveHelper && isAliveHelper();
     }
 
-    bool isAlive()
+    void setCompleteRequestHandler(std::function<void(Response&)>&& handler)
     {
-        return isAliveHelper && isAliveHelper();
+        BMCWEB_LOG_DEBUG << this << " setting completion handler";
+        completeRequestHandler = std::move(handler);
+    }
+
+    std::function<void(Response&)> releaseCompleteRequestHandler()
+    {
+        BMCWEB_LOG_DEBUG << this << " releasing completion handler"
+                         << static_cast<bool>(completeRequestHandler);
+        std::function<void(Response&)> ret = completeRequestHandler;
+        completeRequestHandler = nullptr;
+        return ret;
+    }
+
+    void setIsAliveHelper(std::function<bool()>&& handler)
+    {
+        isAliveHelper = std::move(handler);
     }
 
-    void setCompleteRequestHandler(std::function<void()> newHandler)
+    std::function<bool()> releaseIsAliveHelper()
     {
-        completeRequestHandler = std::move(newHandler);
+        std::function<bool()> ret = std::move(isAliveHelper);
+        isAliveHelper = nullptr;
+        return ret;
     }
 
   private:
-    bool completed{};
-    std::function<void()> completeRequestHandler;
+    bool completed = false;
+    std::function<void(Response&)> completeRequestHandler;
     std::function<bool()> isAliveHelper;
 
     // In case of a JSON object, set the Content-Type header