How do I execute a MongoDB js script using the Java MongoDriver

Question

I have implemented a JavaScript function inside the Mongodb server using this example.

It works fine when I use mongo shell, but I want to run it from inside a Java program. This is the code:

public String runFunction() {

    CommandResult commandResult1 = db.command("db.loadServerScripts()");
    CommandResult commandResult2 = db.command("echoFunction(3)");

    return commandResult2.toString();
}

I don't understand the result.

Answer 1

The previous answers does not work in MongoDB 3.4+. Th proper way to do this in version 3.4 and above is to create a BasicDBObject and use it as the parameter of Database.runCommand(). Here's an example.

final BasicDBObject command = new BasicDBObject();
            command.put("eval", String.format("function() { %s return;}}, {entity_id : 1, value : 1, type : 1}).forEach(someFun); }", code));
            Document result = database.runCommand(command);