How to configure tomcat to work with mysql in OpenShift? - mysql

Question

I just discovered OpenShift and i love it! And i would like to try it with a tomcat app that communicates with mysql.I was able to install tomcat through this tutorial
and my tomcat server is up and running !I also installed mysql and phpmyadmin,but now i have to deploy my servlet in the tomcat server .My servlet communicates with mysql but i cant find where to insert the variables that Openshift give me !Does anyone have any idea?
Thnx in advandce Andi :)
OPENSHIFT VARIABLES ARE:
Root User :andi
RootPassword: andi
Connection URL: mysql://$OPENSHIFT_MYSQL_DB_HOST:$OPENSHIFT_MYSQL_DB_PORT/
MY SERVLET:
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.mysql.jdbc.Connection;
import com.mysql.jdbc.PreparedStatement;
#WebServlet("/HelloWorldServlet")
public class HelloWorldServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
public HelloWorldServlet() {
super();
}
protected void doGet(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
String titulli = request.getParameter("titulli");
String ingredientet = request.getParameter("ingredientet");
String receta = request.getParameter("receta");
final String url = "jdbc:mysql://localhost/andi";
final String user = "andi";
final String password = "andi";
try {
// jdbc try
Class.forName("com.mysql.jdbc.Driver");
Connection con = (Connection) DriverManager.getConnection(url, user,
password);
// insert values into the first table
PreparedStatement s = (PreparedStatement) con
.prepareStatement("INSERT INTO recetat(titulli,ingredientet,receta) VALUES (?,?,?)");
s.setString(1, titulli);
s.setString(2, ingredientet);
s.setString(3, receta);
s.executeUpdate();
} catch (SQLException e) {
e.printStackTrace();
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
PrintWriter out = response.getWriter();
out.println("Receta u ruajt me sukses ne server !");
System.out.println(titulli+ingredientet+receta);
}
}
like you can see i dont know where to insert the
Connection URL: mysql://$OPENSHIFT_MYSQL_DB_HOST:$OPENSHIFT_MYSQL_DB_PORT/
variable...

Answer 1

OpenShift puts the MySQL host and port as environment variables on exactly that name. In Java terms, they are available by
String host = System.getenv("OPENSHIFT_MYSQL_DB_HOST");
String port = System.getenv("OPENSHIFT_MYSQL_DB_PORT");
Then, compose the JDBC URL as follows
String url = String.format("jdbc:mysql://%s:%s/andi", host, port);
The normal approach, however, is to create a connection pooled datasource in context.xml and obtain that by JNDI instead.

Answer 2

Somewhat related - you can now install tomcat directly (without following the DIY steps) but running
rhc app create <name> jbossews-1.0
JBoss EWS is a maintained and supported version of Tomcat from Red Hat - all the same bits. Also, starting next week the rhc client tools will support
rhc app create <name> tomcat6
To make it even simpler.