AssertionGeneration.java

package com.sap.refapp;

import java.util.List;
import java.io.IOException;
import java.security.Principal;
import java.sql.CallableStatement;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Map;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.sap.core.jpaas.security.saml2.service.SAML2BearerAssertionData;
import com.sap.core.jpaas.security.saml2.service.SAML2BearerGenerationService;
import com.sap.security.um.service.UserManagementAccessor;
import com.sap.security.um.user.PersistenceException;
import com.sap.security.um.user.User;
import com.sap.security.um.user.UserProvider;

/**
 * Servlet implementation class AssertGen
 */
public class AssertGen extends HttpServlet {
	private static final long serialVersionUID = 1L;
    private String assertion = null; 
    
    /**
     * @see HttpServlet#HttpServlet()
     */
    public AssertGen() {
        super();
        // TODO Auto-generated constructor stub
    }

	/**
	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		Principal userPrincipal = request.getUserPrincipal();
		String fname,lname,mail;
		String userName = request.getRemoteUser();
		User user = null;
		try {
		UserProvider userProvider = UserManagementAccessor.getUserProvider();
		user = userProvider.getUser(userName);
		} catch (PersistenceException e) {	
			e.printStackTrace();
		}
		try{
		fname = user.getAttribute("firstname");
		lname = user.getAttribute("lastname");
		mail = user.getAttribute("email");
		response.getWriter().println("Hello!" + userName + fname + lname + mail);
		
		SAML2BearerAssertionData data = new SAML2BearerAssertionData();
		Map<String, List<Object>> attributes = new HashMap<String, List<Object>>();
		data.setRecepientURI("http://example.com");
		data.setUserId(userName);
		
		List<Object> attValues = new ArrayList<Object>();    
		attValues.add("TestName");    
		attributes.put("testname", attValues);    
		data.setAttributes(attributes);
		data.setAudience("http://hostname:port/");
		data.setAuthnContextClassRef("urn:oasis:names:tc:SAML:2.0:ac:classes:PasswordProtectedTransport");
		data.setAssertionIssuer("<App certificate entityID>");
		SAML2BearerGenerationService service = SAML2BearerGenerationService.getInstance();
		response.getWriter().println("Generate Token");
		assertion = service.generateBearerAsserion(data);
		
		response.getWriter().println("SAML Token: " + assertion);
		String dbUser = establishConnection();
		response.getWriter().println("Database User : " + dbUser);
		
		} catch (Exception e) {	
			e.printStackTrace();
		}
		
	}

	/**
	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
	}
	
	public String establishConnection(){
		
		String result = null;
		
		try{
			Class.forName("com.sap.db.jdbc.Driver");
			java.sql.Connection conn = java.sql.DriverManager.getConnection("jdbc:sap://<hostname>:30015","",assertion);
			Statement stmt = conn.createStatement();
			ResultSet rs = stmt.executeQuery("SELECT CURRENT_USER FROM SYS.M_DATABASE");
			if(rs.next()){
				result = rs.getString("CURRENT_USER");
			}
			stmt.close();
			conn.close();
			
		}catch(Exception e){
			System.out.println("Exception: " + e);
			
		}
		return result;
		
	}

}