Login to or logout from Drupal in Java

I wanted to post and update a lot of biographical data to Drupal, but I could only do so by first logging in – manually. How tedious. So I thought that it would a good general tool to be able to programmatically login and logout of Drupal without having to go through the GUI each time. But how to do it?

The method I settled on was to use Java's HttpURLConnection class. I would open a http connection to Drupal, send it my username and password, get back a cookie and then send my stuff. When I had finished I could then programmatically logoff. Cool. But it turned out to be a bit more difficult than I had imagined. i used POST because I couldn't make GET work properly, and all applications seemed to use POST. Some of the parameters are probably not necessary, but I added them all from the packets I captured in Wireshark, and at least this way it works:

import java.net.URL; import java.net.URLConnection; import java.net.HttpURLConnection; import java.io.OutputStream; import java.util.Random; /** * Login/logout of Drupal programmatically * @author desmond */ public class DrupalLogin { String boundary; public DrupalLogin() { boundary = "----------------------------"+randomHex(12); } String randomHex( int size ) { String str = "0123456789abcdef"; Random r = new Random(System.currentTimeMillis()); StringBuilder sb = new StringBuilder(); for ( int i=0;i<size;i++ ) { int index = r.nextInt(16); char c = str.charAt(index); sb.append( c ); } return sb.toString(); } void encodeParam( StringBuilder sb, String key, String value, boolean last ) { sb.append("Content-Disposition: form-data; name=\""); sb.append( key ); sb.append( "\"\r\n\r\n" ); sb.append( value ); sb.append( "\r\n--"); sb.append( boundary ); if ( last ) sb.append("--"); else sb.append("\r\n"); } String buildLoginRequest( String user, String password ) { StringBuilder sb = new StringBuilder(); sb.append("--"); sb.append(boundary); sb.append("\r\n"); encodeParam( sb, "name", user, false ); encodeParam( sb, "pass", password, false ); encodeParam( sb, "form_id", "user_login", false ); encodeParam( sb, "op", "Log in", true ); return sb.toString(); } String login( String host, String user, String password ) throws Exception { String cookie = null; URL login = new URL("http://"+host+"/user/login"); URLConnection conn = login.openConnection(); HttpURLConnection hconn = (HttpURLConnection) conn; hconn.setDoOutput( true ); hconn.setRequestProperty("Accept","*/*"); hconn.setRequestProperty("Host",host); hconn.setRequestProperty("Expect","100-continue"); String body = buildLoginRequest( user, password); hconn.setRequestProperty( "Content-length", Integer.toString(body.getBytes().length) ); hconn.setRequestProperty("Connection","keep-alive"); hconn.setRequestProperty("Content-Type", "multipart/form-data; boundary="+boundary); // without this Drupal redirects and we lose the cookie hconn.setInstanceFollowRedirects(false); OutputStream output = hconn.getOutputStream(); output.write( body.getBytes() ); output.write("\r\n\r\n".getBytes()); output.flush(); output.close(); String headerName=null; for (int i=1; (headerName = conn.getHeaderFieldKey(i))!=null; i++) { if (headerName.equals("Set-Cookie")) { System.out.println("logged in!"); cookie = conn.getHeaderField(i); } } if ( cookie ==null) System.out.println("failed to login. error=" +hconn.getResponseCode()); return cookie; } public void logout( String host, String cookie ) throws Exception { URL logout = new URL("http://"+host+"/user/logout"); URLConnection newConn = logout.openConnection(); HttpURLConnection hconn2 = (HttpURLConnection) newConn; hconn2.setRequestProperty("Host",host); hconn2.setRequestProperty("Accept", "text/html,application/xhtml+xml,application/xml;q=0.9," +"*/*;q=0.8"); hconn2.setRequestProperty("Accept-Language", "en-US,en;q=0.5"); hconn2.setRequestProperty("Accept-Encoding", "gzip, deflate"); hconn2.setRequestProperty("Referer", "http://"+host+"/user"); hconn2.setRequestProperty("Cookie", "has_js=1; "+cookie); hconn2.setRequestProperty("Connection","keep-alive"); hconn2.connect(); int code = hconn2.getResponseCode(); if ( code ==200 ) System.out.println("Logged out!"); else System.out.println("Not logged out. code="+code); } /** * Just a test of Drupal login * @param args the command line arguments */ public static void main(String[] args) { try { DrupalLogin dl = new DrupalLogin(); String cookie = dl.login( "mydrupalhost.com", "anonymous", "secret" ); if ( cookie != null ) dl.logout( "mydrupalhost.com", cookie ); } catch ( Exception e ) { e.printStackTrace(System.out); } } }