I'm used to thinking in Java and I'm trying to get my head around node.js. My program needs to log information when things go wrong, and I find I'm having to put in a lot of boilerplate code in my node.js program to get what I'd get for free in Java.

My question boils down to:

• is there an easier/non-boilerplate way to get stack-like information in a chain of callbacks? and/or
• am I guilty of failing to grasp node.js properly, and trying to force asynchronous node.js to be more like synchronous Java?

Java Example

Here's a noddy Java program which tries (and fails) to connect to a Mongo database: import java.net.UnknownHostException;

import com.mongodb.Mongo;

public class Test {

    public static void main(final String[] args) throws UnknownHostException {
        final Mongo mongo = a();
    }

    private static Mongo a() throws UnknownHostException {
        return b();
    }

    private static Mongo b() throws UnknownHostException {
        return c();
    }

    private static Mongo c() throws UnknownHostException {
        return new Mongo("non-existent host");
    }

}

...which gives this helpful stack output:

Exception in thread "main" java.net.UnknownHostException: non-existent host
at java.net.Inet6AddressImpl.lookupAllHostAddr(Native Method)
at java.net.InetAddress$1.lookupAllHostAddr(Unknown Source)
at java.net.InetAddress.getAddressesFromNameService(Unknown Source)
at java.net.InetAddress.getAllByName0(Unknown Source)
at java.net.InetAddress.getAllByName(Unknown Source)
at java.net.InetAddress.getAllByName(Unknown Source)
at java.net.InetAddress.getByName(Unknown Source)
at com.mongodb.ServerAddress.updateInetAddress(ServerAddress.java:204)
at com.mongodb.ServerAddress.<init>(ServerAddress.java:73)
at com.mongodb.ServerAddress.<init>(ServerAddress.java:46)
at com.mongodb.Mongo.<init>(Mongo.java:138)
at Test.c(Test.java:20)
at Test.b(Test.java:16)
at Test.a(Test.java:12)
at Test.main(Test.java:8)

(In particular, the last 4 lines show me "what was happening" in my own code at the time the Mongo error occurred.)

Node.js Example

Here's my attempt to re-write my program in node.js:

a(function (err, mongo) {
    if (err) {
        console.log("Something went wrong in main");
        console.log(err);
    }
});

function a(callback) {
    b(function (err, mongo) {
        if (err) {
            console.log("Something went wrong in a()");
            return callback(err);
        }

        return callback(null, mongo);
    });
}

function b(callback) {
    c(function (err, mongo) {
        if (err) {
            console.log("Something went wrong in b()");
            return callback(err);
        }

        return callback(null, mongo);
    });
}

function c(callback) {
    var MongoClient = require('mongodb').MongoClient;
    return MongoClient.connect('mongodb://non-existent host/', function (err, mongo) {
        if (err) {
            console.log("Something went wrong in c()");
            return callback(err);
        }

        return callback(null, mongo);
    });
}

...which gives this output:

Something went wrong in c()
Something went wrong in b()
Something went wrong in a()
Something went wrong in main
[Error: failed to connect to [non-existent host:27017]]

But to get this output, I have to put in lots of boilerplate code throughout my program, which is going to be a pain to police as my program gets larger and I have a whole development team.

Can I get this stack-like output another way? Is it un-node-like to expect this kind of output?