Golang vs. Ratpack

30 Oct 2019

Over the past few weeks I’ve started learning Ratpack since it is a fairly popular framework where I work. It is an emerging new framework that is really centered around making Asynchronous programming in JVM languages easier.

Additionally, I’ve also been working on a side project at work written in GoLang. While Golang(Go) can be considered a language and ratpack more of a framework(Since it can be written in Kotlin or Groovy which are both languages), I’m still going to compare them both as if they were languages since Ratpack really brings along its own syntax.

So just a little bit about the two projects for background as they do differ in scope quite a bit.

Ratpack Project

The Ratpack project I chose was basically to have a simple API endpoint that accepts a 4 alpha-numeric code that represents a Target store and returns the store operating hours as well as if the store is a new store(has not opened to public yet) or if it is an existing store. This means I not only had to expose a REST endpoint but I also had to utilize an HTTP client to call a REST API hosted somewhere else. Then parse the results and return them back to the user that called my endpoint.

Quite literally just a small project to learn Ratpack. I tried to keep the scope as small as possible to avoid unnecessary injecting extra “learning adventures” into the tech stack.

Golang Project

The Golang project is a client library that allows others to import it and easily interact with a database abstraction service run at Target. I can’t really go into details about that project, but basically the client is simply a wrapper around another API. I was initially inspired by a few other client libraries I wrote in Python and how easy it is to wrap API’s using Python’s object model where you can do things like this:

import requests

class APIWrapper(object):
  def __init__(self, url, user, pass):
    self.url = url
    self.user = user
    self.pass = pass

  def __getattr__(self, name):
    return path(name)

  def path(self, path):
    newurl = self.url + '/' + path
    return APIWrapper(newurl, self.user, self.pass)

  def call(self, method):
    request_method = getattr(requests, method)
    return request_method(newurl, auth=(self.user, self.pass))

Then if the API you are calling is laid out such that endpoints are truly Restful such as /foo/<object>/<key> and allow you to do POST, PUT, GET, DELETE against these types of URL schemes you can easily use this wrapper such as:

client = APIWrapper('http://example.com', 'user', 'pass')
r = client.foo.myobject.mykey("GET")

– or –

r = client.path('foo').path('myobject').path('mykey')("GET")

Now r will have a response object after making a GET to http://example.com/foo/myobject/mykey

Disclaimer: I didn’t test the above code, so there are probably some simple mistakes in it, however, the concept works great!

So back to Go, the idea was that I wanted to replicate the APIWrapper pattern. Yes, I’m sure there is some specific technical term for what APIWrapper is doing but I’m not really big on technical terms so APIWrapper pattern it is!

Turns out you can mostly replicate the python code above, but since I’m fairly new to Golang I wasn’t sure if you could easily replicate the __getattr__ portion so just stuck with implementing Path(...) which works fine and is a little more straight forward on what is going on.


Before I dive into my comparison it is probably best to talk about some of my personal preferences and biases. One thing I dislike about reading other articles like this is that they don’t talk about their personal preferences, but you can clearly see them defined in how they compare things.

Probably the most important things to me, which will be no surprise to anybody that works with me, is that I have a very strong affinity towards VIM, Bash, Linux and Python. Anything that falls outside of this tech ecosystem better be easy to mold into it. That is, if I cannot write code easily in VIM and get all the niceties such as syntax highlighting, code formatting, code building, code running can take a hike right off a cliff into a pile of sharp rocks!


It is probably a bit silly to compare the two using these two projects since the projects are fundamentally different, but I think the core comparison will still be valid.

Overall it probably won’t surprise you, but I liked my Golang experience more. What really did surprise me though was that in all of the Groovy/Java/Spring/Beans experiences I’ve had in the past, Ratpack has been the best. Maybe it can just hike to the top of the cliff and not fall into the pit of rocks.


You can tell that things are really thought out well. The learning curve was not really not that steep. You don’t get burdened by having to learn so many things all at once. Simply write your code. Run go build. Execute code! Really, that is it. This is of course assuming you have jumped through the GOPATH hurdles. Really, WTF was Google thinking with this whole GOPATH thing? All I can say is, if you want to do a Go project just make a directory in your home directory called src and then for every code repository site you upload to make a directory for it (Example ~/src/github.com). Then put your project inside that directory(Example ~/src/github.com/myproject). Last, you should just be able to set your GOPATH to ~/ and things “should” work.

Did I mention that VIM picks up Go syntax pretty much natively? Mix that with the Ale plugin and you get code formatting and compile errors right in VIM!

Few other things that I really liked:

  • Godoc - wow, comes with the language basically and standardized formatting for docs. Tool is super easy to get and use
  • The compiler is so picky about formatting. No more “well I like 2 spaces” or “i do it this way”. No! This is the way everybody formats their code and you don’t get to compile unless you do it that way.
  • Works easily with VIM. It really doesn’t matter what editor you use, but so far in my experience if you cannot easily write in VIM and get syntax highlighting, formatting, compiler errors working out of the box, there are other issues. Java is honestly impossible to get to work in VIM without doing crazy things involving Eclipse. Scares the shit out of me.
  • Tons of documentation for everything and things make sense with very little effort. Ratpack specifically is a nightmare when it comes to finding information about anything. It really feels like tribal knowledge here at Target. If you want to learn Ratpack you have to either endure the learning curve of figuring everything out or find somebody who already knows it and learn from them. Also, who else uses Ratpack in the industry? Maybe there are quite a few others, but seems like it is not really widely used?
  • You can compile for whatever OS you want. Don’t need a JVM installed just run the binary. This is also a pitfall of python/ruby… You can’t just run the app, you have to ensure python is installed and also whatever libraries it needs.

Writing in Go was fun and each thing I had to learn wasn’t a huge hurdle as the docs are so straight forward for anything in Golang(not to mention there are docs for everything).


Ratpack started off rough as I knew I would have to also learn how to navigate around IntelliJ since Java/Groovy just don’t work in VIM. Ya, you can enable VIM shortcuts in IntelliJ, but it really just isn’t the same and you end up relearning a bunch of keystrokes to get the same functionality. I just want the same editor no matter where I am or what I’m doing(I’m writing this post in VIM!)

When I was developing the Ratpack app it felt overwhelming for the most part. Where do I start? Docs say to do this, if you are lucky and there are docs, but every example on the web is different than what that says. Who do I trust now, stack overflow or Ratpack docs? And don’t even get me started on the Ratpack docs, just head over yourself and learn about the Registry. Nothing like finding a few TODO blocks in there. It felt like the docs were written by somebody who knows Ratpack too well and very minor things were skipped over.

It felt like being a toddler. One minute you are just blasting away at code happy as can be and the next minute you are crying in your room because null pointer exception and don’t understand what changed nor what is going on. It really felt like everything is this smoke and mirrors show. Where does this variable come from? 10 minutes of digging later on the Google: “It is injected automatically for you through this mechanism that you would only know about if you have been a Java developer for 5 years”. Maybe I just really hate code automatic code injection. It was something I really despised about Spring Boot as well.

One thing that really made the whole experience tough was the fact that in order to even start doing anything with Ratpack, I had to first figure out how to use IntelliJ. Then how do I setup Gradle. Then how do I start writing the project. There was too much involved in just getting started. Maybe it is an unfair comparison since there are quite a few IntelliJ users out there and they might look at using VIM as the same learning curve.

Few other thoughts:

  • Groovy, Kotlin, Scala? What the hell is going on? So there are many different languages now that are based on the JVM or is it Java? Can we just kill java and move on now that it is 2019?
  • Ratpack specifically is a nightmare when it comes to finding information about anything. If you want to learn Ratpack you have to either endure the learning curve of figuring everything out or find somebody who already knows it and learn from them.

Writing the app in Ratpack was quite the journey. In the end I did feel like I had finally gotten to the point where I understood at a very minimal level, how it works. I’m still not 100% sure about how the Registry works and how all of the auto-injection works either, but I feel that knowledge would come after working with it a bit more.

I did find an article that really helped which I highly recommend if you are going to plunge into Ratpack. https://danhyun.github.io/mastering-async-ratpack/

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