Accessing session values from .js file

Question

I have set the user ID and password values from a login page for a session using the following code in a .jsp file:

    <%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>
<!DOCTYPE html>
<html>
    <head>
        <meta charset="ISO-8859-1">
        <title>Insert title here</title>
    </head>
    <body>
        <script>alert("Hey")</script>
        <%
            String userName = request.getParameter("username");
            String password = request.getParameter("password");
            session.setAttribute("username", userName);
            session.setAttribute("password", password);
            response.sendRedirect("somefile.jsp");
        %>
    </body>

I want to access the username in a .js file, to send it to REST API. Tried this:

var uName = <%=session.getAttribute("username")%>;

But that doesn't work, since <% won't get parsed as needed in a .js file. Any suggestions?

`` — This is the 21st century. We have Unicode now. – Quentin Dec 10 '18 at 15:20 — Quentin, Dec 10 '18 at 15:20

score 1 · Answer 1 · answered Dec 10 '18 at 15:20

You have four options.

Read the data from the URL directly with JS and don't involve JSP at all (but you shouldn't be passing passwords about in the query string in the first place)
Generate your JS from JSP
Inject the data into the HTML (e.g. using a data-* attribute) when the HTML document is generated from JSP and then read it from there with JS
Create a web service that supplies the data and make an Ajax request to it

Accessing session values from .js file

1 Answers1