Add UpgradeSync example

examples/UpgradeSync.cpp

@@ -0,0 +1,77 @@
+/* We simply call the root header file "App.h", giving you uWS::App and uWS::SSLApp */
+#include "App.h"
+
+/* This is a simple WebSocket "sync" upgrade example.
+ * You may compile it with "WITH_OPENSSL=1 make" or with "make" */
+
+int main() {
+    /* ws->getUserData returns one of these */
+    struct PerSocketData {
+        /* Define your user data */
+        int something;
+    };
+
+    /* Keep in mind that uWS::SSLApp({options}) is the same as uWS::App() when compiled without SSL support.
+     * You may swap to using uWS:App() if you don't need SSL */
+    uWS::SSLApp({
+        /* There are example certificates in uWebSockets.js repo */
+	    .key_file_name = "../misc/key.pem",
+	    .cert_file_name = "../misc/cert.pem",
+	    .passphrase = "1234"
+	}).ws<PerSocketData>("/*", {
+        /* Settings */
+        .compression = uWS::SHARED_COMPRESSOR,
+        .maxPayloadLength = 16 * 1024,
+        .idleTimeout = 10,
+        .maxBackpressure = 1 * 1024 * 1024,
+        /* Handlers */
+        .upgrade = [](auto *res, auto *req, auto *context) {
+
+            /* You may read from req only here, and COPY whatever you need into your PerSocketData.
+             * PerSocketData is valid from .open to .close event, accessed with ws->getUserData().
+             * HttpRequest (req) is ONLY valid in this very callback, so any data you will need later
+             * has to be COPIED into PerSocketData here. */
+
+            /* Immediately upgrading without doing anything "async" before, is simple */
+            res->template upgrade<PerSocketData>({
+                /* We initialize PerSocketData struct here */
+                .something = 13
+            }, req->getHeader("sec-websocket-key"),
+                req->getHeader("sec-websocket-protocol"),
+                req->getHeader("sec-websocket-extensions"),
+                context);
+
+            /* If you don't want to upgrade you can instead respond with custom HTTP here,
+             * such as res->writeStatus(...)->writeHeader(...)->end(...); or similar.*/
+
+            /* Performing async upgrade, such as checking with a database is a little more complex;
+             * see UpgradeAsync example instead. */
+        },
+        .open = [](auto *ws) {
+            /* Open event here, you may access ws->getUserData() which points to a PerSocketData struct.
+             * Here we simply validate that indeed, something == 13 as set in upgrade handler. */
+            std::cout << "Something is: " << static_cast<PerSocketData *>(ws->getUserData())->something << std::endl;
+        },
+        .message = [](auto *ws, std::string_view message, uWS::OpCode opCode) {
+            /* We simply echo whatever data we get */
+            ws->send(message, opCode);
+        },
+        .drain = [](auto *ws) {
+            /* Check ws->getBufferedAmount() here */
+        },
+        .ping = [](auto *ws) {
+            /* You don't need to handle this one, we automatically respond to pings as per standard */
+        },
+        .pong = [](auto *ws) {
+            /* You don't need to handle this one either */
+        },
+        .close = [](auto *ws, int code, std::string_view message) {
+            /* You may access ws->getUserData() here, but sending or
+             * doing any kind of I/O with the socket is not valid. */
+        }
+    }).listen(9001, [](auto *token) {
+        if (token) {
+            std::cout << "Listening on port " << 9001 << std::endl;
+        }
+    }).run();
+}