add endpoint to refresh auth token

Server/controllers/authController.js

@@ -173,6 +173,68 @@ const loginUser = async (req, res, next) => {
 	}
 };
 
+/**
+ * Generates new auth token if the refresh token is valid
+ * @function
+ * @param {Express.Request} req - The Express request object.
+ * @property {Object} req.headers - The parameter of the request.
+ * @param {Express.Response} res - The Express response object.
+ * @param {function} next - The next middleware function.
+ * @returns {Object} The response object with a success status, a message indicating new auth token is generated.
+ * @throws {Error} If there is an error during the process such as any of the token is not received
+ */
+const refreshAuthToken = (req, res, next) => {
+  try {
+    // check for refreshToken 
+    const refreshToken = req.headers["x-refresh-token"];
+
+    if (!refreshToken) {
+      // No refresh token provided
+      const error = new Error(errorMessages.NO_REFRESH_TOKEN);
+      error.status = 401;
+      error.service = SERVICE_NAME;
+      error.method = "handleExpiredJwtToken";
+      return next(error);
+    }
+
+    // Verify refresh token
+    const { refreshTokenSecret } = req.settingsService.getSettings();
+    jwt.verify(refreshToken, refreshTokenSecret, (refreshErr, refreshDecoded) => {
+      if (refreshErr) {
+        // Invalid or expired refresh token, trigger logout
+        const errorMessage =
+          refreshErr.name === "TokenExpiredError"
+            ? errorMessages.EXPIRED_REFRESH_TOKEN
+            : errorMessages.INVALID_REFRESH_TOKEN;
+        const error = new Error(errorMessage);
+        error.status = 401;
+        error.service = SERVICE_NAME;
+        return next(error);
+      }
+    });
+
+    // Refresh token is valid and unexpired, generate new access token
+    const oldAuthToken = getTokenFromHeaders(req.headers);
+    const { jwtSecret } = req.settingsService.getSettings();
+
+    const payloadData = jwt.verify(oldAuthToken, jwtSecret, { ignoreExpiration: true });
+    // delete old token related data
+    delete payloadData.iat;
+    delete payloadData.exp;
+
+    const newAuthToken = issueToken(payloadData, tokenType.ACCESS_TOKEN, req.settingsService.getSettings());
+
+    return res.status(200).json({
+      success: true,
+      msg: successMessages.AUTH_TOKEN_REFRESHED,
+      data: { user: payloadData, token: newAuthToken, refreshToken: refreshToken },
+    });
+  } catch (error) {
+    next(handleError(error, SERVICE_NAME, "refreshAuthToken"));
+  }
+};
+
+
 /**
  * Edits a user's information. If the user wants to change their password, the current password is checked before updating to the new password.
  * @async
@@ -455,6 +517,7 @@ export {
 	issueToken,
 	registerUser,
 	loginUser,
+  refreshAuthToken,
 	editUser,
 	checkSuperadminExists,
 	requestRecovery,

Server/routes/authRoute.js

@@ -11,6 +11,7 @@ const upload = multer();
 import {
 	registerUser,
 	loginUser,
+  refreshAuthToken,
 	editUser,
 	requestRecovery,
 	validateRecovery,
@@ -23,6 +24,7 @@ import {
 //Auth routes
 router.post("/register", upload.single("profileImage"), registerUser);
 router.post("/login", loginUser);
+router.post("/refresh", refreshAuthToken);
 router.put("/user/:userId", upload.single("profileImage"), verifyJWT, editUser);
 router.get("/users/superadmin", checkSuperadminExists);
 router.get("/users", verifyJWT, isAllowed(["admin", "superadmin"]), getAllUsers);

Server/utils/messages.js

@@ -75,6 +75,7 @@ const successMessages = {
   AUTH_RESET_PASSWORD: "Password reset successfully",
   AUTH_ADMIN_CHECK: "Admin check completed successfully",
   AUTH_DELETE_USER: "User deleted successfully",
+  AUTH_TOKEN_REFRESHED: "Auth token is refreshed",
 
   // Check Controller
   CHECK_CREATE: "Check created successfully",