added CORS

source/login/SessionHandler.cpp

@@ -0,0 +1,77 @@
+#include "SessionHandler.hpp"
+#include <random>
+#include <thread>
+#include "crow/logging.h"
+
+using namespace login;
+
+// generate random string
+std::string randomString(size_t length) {
+    static const char charset[] =
+        "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
+    std::string result;
+    result.resize(length);
+    std::mt19937 rng(std::random_device{}());
+    std::uniform_int_distribution<> dist(0, sizeof(charset)-2);
+    for (size_t i = 0; i < length; ++i) result[i] = charset[dist(rng)];
+    return result;
+}
+
+SessionHandler::SessionHandler()
+: cleanupThread(std::thread(&SessionHandler::cleanupWorker, this))
+, stopCleanupThread(false)
+{
+}
+
+SessionHandler::~SessionHandler() {
+    stopCleanupThread = true;
+    if (cleanupThread.joinable())
+        cleanupThread.join();
+}
+
+void SessionHandler::cleanupWorker(){
+    while (!stopCleanupThread) {
+        std::this_thread::sleep_for(std::chrono::minutes(5));
+        auto now = std::chrono::steady_clock::now();
+        {
+            std::lock_guard<std::mutex> lock(sessionMutex);
+            for (auto it = sessions.begin(); it != sessions.end();) {
+                if (it->second.isExpired(now)){
+                    CROW_LOG_INFO << "Session " << it->first << " expired for userId: " << it->second.userId();  
+                    it = sessions.erase(it);
+                }
+                else {
+                    ++it;
+                }
+            }
+        }
+    }
+}
+
+std::optional<std::string> SessionHandler::createSession(int userId){
+    std::string sessionId = randomString(Session::SESSION_ID_SIZE);
+    std::lock_guard<std::mutex> lock(sessionMutex);
+    if (!sessions.emplace(sessionId, Session(userId)).second){
+        return {};
+    }
+    return sessionId;
+}
+
+std::optional<int> SessionHandler::isSessionValid(const std::string& sessionId){
+    auto now = std::chrono::steady_clock::now();
+    std::lock_guard<std::mutex> lock(sessionMutex);
+    
+    auto it = sessions.find(sessionId);
+    if(it != sessions.end()){
+        if (it->second.isExpired(now)){
+            CROW_LOG_INFO << "Session " << it->first << " expired for userId: " << it->second.userId();  
+            it = sessions.erase(it);
+            return {};
+        }
+        it->second.extend(now); // extend session life time
+        return it->second.userId();
+    }
+    return {};
+}
+
+