Changelog.txt implementation

README.md

@@ -7,6 +7,7 @@ Currently can upload new files, and update existing ones, and delete files from
 # todos: 
 - ~~add deletion~~
 - ~~update files~~
+- ~~changelog.txt~~
 
 compile:
 ```

server.cpp

@@ -21,9 +21,9 @@ bool fileExists(const std::string& filename) {  // check if the file exists
 }
 
 time_t getFileLastModifiedTime(const std::string& filename) { // get the last modified time of the file
-    struct stat buffer;
-    stat(filename.c_str(), &buffer);
-    return buffer.st_mtime;
+    struct stat buffer; // create a buffer to store the file information
+    stat(filename.c_str(), &buffer); // get the file information and store it in the buffer
+    return buffer.st_mtime; // return the last modified time
 }
 
 void receiveFile(int clientSocket, const std::string& filename) {
@@ -69,8 +69,18 @@ void receiveFile(int clientSocket, const std::string& filename) {
 }
 
 void synchronizeFiles(int clientSocket) { // synchronize the files
+    #include <fstream> // Add missing include directive for the <fstream> library
+
     std::vector<std::string> files; // vector to store received filenames from local directory
 
+    // create changelog if it doesn't exist
+    std::ofstream changelog(SERVER_FOLDER "changelog.txt", std::ios::app); // open the changelog file in append mode (to append new logs to the end of the file)
+    if (!changelog.is_open()) {
+        std::cerr << "Error opening changelog file" << std::endl;
+        return;
+    }
+
+
     // Receive missing files and update existing ones
     while (true) { 
         // Receive file name from the client
@@ -82,26 +92,35 @@ void synchronizeFiles(int clientSocket) { // synchronize the files
             break;  // End of file list
         }
         std::string filename(buffer); // convert the buffer to a string to get the file name 
-        files.push_back(filename);
+        files.push_back(filename); // add the file name to the vector of files to compare later on the server side (to delete files that are no longer existing on client side)
         send(clientSocket, "OK", 2, 0); // send the acknowledgment to the client that the file name was received successfully
 
         time_t lastModifiedTime; // create a variable to store the last modified time
         std::memset(buffer, 0, sizeof(buffer)); // reset the buffer
         bytesRead = recv(clientSocket, buffer, sizeof(buffer), 0); // receive the last modified time from the client
-        if (bytesRead != sizeof(lastModifiedTime)) {
+        if (bytesRead != sizeof(lastModifiedTime)) { // if the last modified time is not received correctly
             std::cerr << "Error receiving last modified time for: " << filename << std::endl;
             continue; // continue to the next file
         }
 
         std::memcpy(&lastModifiedTime, buffer, sizeof(lastModifiedTime)); // copy the last modified time from the buffer to the variable
 
         if (!fileExists(SERVER_FOLDER + filename) || lastModifiedTime > getFileLastModifiedTime(SERVER_FOLDER + filename)) {
+            bool existing = fileExists(SERVER_FOLDER + filename); // check if the file already exists before receiving it, to know if we need to log an update or a receive
             send(clientSocket, "SEND", 4, 0); // send the message to the client to send the file
-            if (fileExists(SERVER_FOLDER + filename)) std::cout<<"[UPDATED]";
             receiveFile(clientSocket, filename); // receive the file from the client
+            time_t now = time(0); // get the current time to log it
+            if (existing){ // if the file already existed before receiving, we log an update
+                changelog << now << " [UPDATED] "<< filename << " from " << getFileLastModifiedTime(SERVER_FOLDER + filename) << " to " << lastModifiedTime << std::endl;
+            } else {
+                changelog << now << " RECEIVED "<< filename << std::endl; // if the file didn't exist before receiving, we log a receive
+            }
+
         } else {
             send(clientSocket, "SKIP", 4, 0); // send the message to the client to skip the file if the file already exists
         }
+
+        changelog.close(); // close the changelog file
     }
 
     // compare client names to files on remote directory, to delete files that are no longer existing on client side
@@ -110,10 +129,12 @@ void synchronizeFiles(int clientSocket) { // synchronize the files
     // check all files in server directory to see if they are in the vector, if not, we delete
     if ((dir = opendir(SERVER_FOLDER)) != nullptr) { // open the server folder and check if it is not null (nullptr)
         while ((ent = readdir(dir)) != nullptr) { // read the directory entries one by one and check if it is not null (nullptr)
-            if ((ent->d_type == DT_REG) && (strcmp(ent->d_name, "server") != 0)) {  // regular file and not "server"
+            if ((ent->d_type == DT_REG) && (strcmp(ent->d_name, "server") != 0) && (strcmp(ent->d_name, "changelog.txt") != 0)) {  // regular file and not "server" or "changelog.txt"
                 std::string filename(ent->d_name); // get the filename from the directory entry
                 if (std::find(files.begin(), files.end(), filename) == files.end()) { // if the file is not found in the vector
-                    std::cout << "[DELETED] " << filename << std::endl;
+                    time_t now = time(0);
+                    changelog << now <<  " [DELETED] " << filename << std::endl;
+                    std::cout << now <<  " [DELETED] " << filename << std::endl;
                     remove((SERVER_FOLDER + filename).c_str()); // delete the file
                 }
             }