Java MongoDB : Authentication example

By default, MongoDB is run in trust environment (authentication with a username and password is NOT required). In this tutorial, we will show you how to start MongoDB in secure mode / enable authentication, and connect with the Java MongoDB driver.

1. Start MongoDB in Secure Mode

Start MongoDB with --auth option, now, MongoDB need username and password to perform any database / collection operations.

mongod --auth

Later, we need to connect to the database “testdb”, so add a user for testing later.

> use admin
> db.addUser("admin","password")
> use testdb
> db.addUser("mkyong","password")

To enable MongoDB authentication, you must first add a user to the special “admin” database, please refer to this MongoDB authentication example for detail guide.

2. Java + MongoDB Authentication example

If MongoDB is started in secure mode, below “insert” operation is no longer valid, and prompts “need to login” error message.

	Mongo mongo = new Mongo("localhost", 27017);
	DB db = mongo.getDB("testdb");

	DBCollection table = db.getCollection("user");

	BasicDBObject document = new BasicDBObject();
	document.put("name", "mkyong");
	table.insert(document);

com.mongodb.CommandResult$CommandFailure: command failed [getlasterror]: 
	{ "serverUsed" : "localhost/127.0.0.1:27017" , "errmsg" : "need to login" , "ok" : 0.0}
	
	at com.mongodb.CommandResult.getException(CommandResult.java:88)
	at com.mongodb.CommandResult.throwOnError(CommandResult.java:134)
	at com.mongodb.DBTCPConnector._checkWriteError(DBTCPConnector.java:142)
	at com.mongodb.DBTCPConnector.say(DBTCPConnector.java:183)
	at com.mongodb.DBTCPConnector.say(DBTCPConnector.java:155)
	at com.mongodb.DBApiLayer$MyCollection.insert(DBApiLayer.java:270)
	at com.mongodb.DBApiLayer$MyCollection.insert(DBApiLayer.java:226)
	at com.mongodb.DBCollection.insert(DBCollection.java:75)
	at com.mongodb.DBCollection.insert(DBCollection.java:59)
	at com.mongodb.DBCollection.insert(DBCollection.java:104)
	at com.mkyong.core.App.main(App.java:40)

Now, using db.authenticate() to perform the authentication, a return value of true = success, false = fail.

package com.mkyong.core;

import java.net.UnknownHostException;
import java.util.Date;
import com.mongodb.BasicDBObject;
import com.mongodb.DB;
import com.mongodb.DBCollection;
import com.mongodb.Mongo;
import com.mongodb.MongoException;

/**
 * Java + MongoDB in Secure Mode
 * 
 */
public class JavaMongoDBAuthExample {
   public static void main(String[] args) {

    try {

	Mongo mongo = new Mongo("localhost", 27017);
	DB db = mongo.getDB("testdb");
			
	boolean auth = db.authenticate("testdb", "password".toCharArray());
	if (auth) {
			
		DBCollection table = db.getCollection("user");

		BasicDBObject document = new BasicDBObject();
		document.put("name", "mkyong");
		table.insert(document);
	
		System.out.println("Login is successful!");
	} else {
		System.out.println("Login is failed!");
	}
	System.out.println("Done");

    } catch (UnknownHostException e) {
	e.printStackTrace();
    } catch (MongoException e) {
	e.printStackTrace();
    }
  }
}

References

1. Java MongoDB authentication example
2. JIRA – DB.authenticate() should use a char[] for the password
3. MongoDB Java Authentication example
4. MongoDB Security Practices and Management