Add closeOnBackpressureLimit option

src/App.h

@@ -139,6 +139,7 @@ public:
         unsigned int maxPayloadLength = 16 * 1024;
         unsigned int idleTimeout = 120;
         unsigned int maxBackpressure = 1 * 1024 * 1024;
+        bool closeOnBackpressureLimit = false;
         fu2::unique_function<void(HttpResponse<SSL> *, HttpRequest *, struct us_socket_context_t *)> upgrade = nullptr;
         fu2::unique_function<void(uWS::WebSocket<SSL, true> *)> open = nullptr;
         fu2::unique_function<void(uWS::WebSocket<SSL, true> *, std::string_view, uWS::OpCode)> message = nullptr;
@@ -200,6 +201,7 @@ public:
         webSocketContext->getExt()->maxPayloadLength = behavior.maxPayloadLength;
         webSocketContext->getExt()->idleTimeout = behavior.idleTimeout;
         webSocketContext->getExt()->maxBackpressure = behavior.maxBackpressure;
+        webSocketContext->getExt()->closeOnBackpressureLimit = behavior.closeOnBackpressureLimit;
         webSocketContext->getExt()->compression = behavior.compression;
 
         httpContext->onHttp("get", pattern, [webSocketContext, behavior = std::move(behavior)](auto *res, auto *req) mutable {

src/WebSocket.h

@@ -64,6 +64,10 @@ public:
 
         /* Skip sending and report success if we are over the limit of maxBackpressure */
         if (webSocketContextData->maxBackpressure && webSocketContextData->maxBackpressure < getBufferedAmount()) {
+            /* Also defer a close if we should */
+            if (webSocketContextData->closeOnBackpressureLimit) {
+                us_socket_shutdown_read(SSL, (us_socket_t *) this);
+            }
             return true;
         }
 

src/WebSocketContextData.h

@@ -64,6 +64,7 @@ public:
 
     /* There needs to be a maxBackpressure which will force close everything over that limit */
     size_t maxBackpressure = 0;
+    bool closeOnBackpressureLimit;
 
     /* Each websocket context has a topic tree for pub/sub */
     TopicTree topicTree;
@@ -143,6 +144,11 @@ public:
 
         /* If we have too much backpressure, simply skip sending from here */
 
+        /* Also (defer) a close if we have too much backpressure if that is what we want */
+        if (maxBackpressure && closeOnBackpressureLimit && asyncSocket->getBufferedAmount() > maxBackpressure) {
+            us_socket_shutdown_read(SSL, (us_socket_t *) asyncSocket);
+        }
+
         /* Reserved, unused */
         return 0;
     }) {