Connect to RServe from JAVA using authentication

Question

• I am running RServe from Server machine using cmd

  Rserve.exe --RS-conf Rserv.conf --RS-port 12306
  

• Rserv.conf file has following content:

  pwdfile RserveAuth.txt
  auth required
  remote enable
  plaintext disable

• RserveAuth.txt has following contents:

  Admin 123456

• I am connecting to R Server from JAVA

  import org.rosuda.REngine.REXPMismatchException;
  import org.rosuda.REngine.REngineException;
  import org.rosuda.REngine.Rserve.RConnection;
  import org.rosuda.REngine.Rserve.RserveException;
  import org.rosuda.REngine.REXP;
  import org.rosuda.REngine.*;
  public class ConnecttoR
  {
    ...
    ...
   public void connectR()
   {
       try 
      { 
          RConnection connection = new RConnection("172.16.33.242",12306); // Works if authentication is not required in Rserv.conf 
      }
      catch (RserveException e) {
      e.printStackTrace();
      } 
      catch(REXPMismatchException e){
      e.printStackTrace();
      }
      catch(REngineException e){
      e.printStackTrace();            
  } 
   }
  }
  

• Connection to Rserve is open to all without username & Password. How shall I add security and allow connection only with valid credentials to access Rserve

Bittner

it looks like your RServer is on Windows Rserve.exe, what is the client user running [Windows, MacOSX, Linux]? Is your production RServer on Windows? Just checking requirements. – Blowfly

@Blowfly RServer is on windows machine and my client can be any Windows/Linux/MacOSX connecting to it. The connection request to Rserver is made from JAVA class and later i run script on Rserve using connection object and pass the output of script to JSP page. – Bittner

FYI. The version of RServe under Windows is limited. The most important limitation is "no parallel connections are supported, subsequent connections share the same namespace" / "sessions are not supported - this is a consequence of the fact that parallel connections are not supported". See rforge.net/Rserve/rserve-win.html under "Please read before downloading/using the Windows version of Rserve!" – Homespun

@AndreyBelykh Good point - you beat me to it. My sense is that one option is to run Rserve via Windows Ubuntu subsystem and then restrict access via ssh. – Blowfly

Answer 1

As you have enabled the authentification after creating the connection as a first command you need to execute the login command. The Java library has a special wrapper for it.

See code below for example use case.

RConnection connection = new RConnection("127.0.0.1",12306);
connection.login("Admin", "123456");
REXP x = connection.eval("R.version.string");
System.out.println(x.asString());

Also, I would recommend using full path as the pwdfile value.

Objectify

Does it use ssh internally to connect? Is it a solution that would work for both Windows and linux box? – Kepler

Yes it will work for any system (I have tested it with MacOS X), and no it uses native socket connections. – Objectify

bcz i followed your solution and got a org.rosuda.REngine.Rserve.RserveException: login failed, request status: authorization failed at org.rosuda.REngine.Rserve.RConnection.login(RConnection.java:399) error – Kepler

Are you sure that the credentials are correct? as You can see the systems are connected, only the username and password did not match. – Objectify

the credentials are correct and also the same as present in the pwdfile in the rserv.conf file. Thanks for verifying though :) – Kepler