Yesterday I was tasked with implementing a Rails front-end onto my Tic-Tac-Toe library. At first I thought it would be trivial, considering how much effort I put into making sure my classes adhered to all the good coding principles and best practices I knew. But obviously things weren’t that simple.
For starters, I wasn’t sure exactly how to reuse my
Game class. As it turned out, it wasn’t really a general
Game class at all, but rather a
ConsoleGame class with only one appropriate environment. Trying to tack a Rails front-end onto it proved impossible, so I either had to generalize it out into a subclass, or pull it apart piece by piece until it was no longer a class at all.
It’s kind of funny how, even though I tried very diligently to make sure my original code could have different front-ends or different back-ends, there were some obvious rough-spots that I only found after actually trying to add a different, non-console-based front-end to it.
This was the first time that I successfully “spiked” a solution too. I wasn’t sure how the Rails controller would look. So I wrote just enough code to show me how the controller would basically function, moved the code to pseudo-code in a temporary file, and deleted the actual code. Then, I was able to tweak the pseudo-code until it appeared to make logical sense, at which point I began to actually implement the controller.
At first I was worried that writing a spike would feel like a waste of time/energy, but it actually felt right. I used it just enough to work out the details of the solution and resolve any unknowns, and once I knew what details would be used, I felt confident in my ability to test-drive the pseudo-implemented API into existence.
Finally by the end of yesterday, I had spec’d and written out my whole
GameController in Rails, and all tests passed!
So this morning, I began to work on spec’ing the views and test-driving them into fruition as well. At one point early on, I thought that was done too! And then there were a few surprises.
For one thing, I was surprised that, after all my seemingly-thorough testing, my Rails app completely lacked an AI. I simply forgot to specify it in any of my tests or pseudo-code.
As Eric had suggested, had I written acceptance tests via a cucumber feature set, this probably would have been caught much earlier on, as writing such tests would have forced me to think of the app “from the outside-in.” But alas, it was still my responsibility to have caught such a glaring omission, and thus it was kind of embarrassing.
Secondly, I realized that, because my classes were so coupled together, the controller’s
move action was awkward to write, and thus some of its corresponding tests were near-impossible to implement in a way that would drive my functionality in the right direction but also not be fragile.
Thirdly, when I tried to instantiate a
Player object with the
AI class inside the
game#move Rails action, it became apparent that I would be forced to drop down to using the
Minimax class. This is because the
Game classes are coupled in such a way that, when you instantiate a
Game with two players, it will set each one’s
opponent variable to the other player instance. In reality, this “hack” was only needed so the “next-move algorithm” of the
Minimax strategy-module would function properly. (It needed to know who itself was and who the opponent was.)
Even though I could (and did) work around the problem, this coupling honestly just needs to be worked out entirely. Otherwise I’ll run into even further problems down the road if I ever want to put a different front-end or back-end onto the game. One problem that this is going to pose, though, is that, if I change the various APIs to work in a different (albeit better) way, not only do I need to write the new API code, but I also need to rewrite every client code that uses them, as well as every test that uses them directly. And considering this might involve a non-trivial change, it could mean up to a day just spent rewriting tests and controllers. Not pretty. I only just began the process this afternoon and already my head is starting to spin. This is good motivation to do it right the first time!
Also, my “clever” solution to keeping “player string representations” completely separate from the player and all encapsulated within the
Board object may not be holding up too well. I’ve noticed that if you choose the 2nd position, you will be
x, but if the other player (
AI) chooses the 1st position next, you will be
o and the
AI will be
x. This is a big I thought I had squashed earlier, but I think I may have inadvertently resurrected it due to my assumption when writing the
Board class that a single given
Board instance will continue to exist throughout the life of the game. However, in my Rails front-end, a new
Board instance is created with each request. Yet another way that I had not full planned for alternative front-ends and back-ends.
As for testing views, that’s still taking me a bit of getting used to. Eric’s guidelines are, test only what has programming in it, ie. code inside a view that is likely to produce variable output. To me, that seems to be missing half the picture. Technically, the
form tag which allows making a move in my game, is never going to change. It has no variable code. But we need to make sure it exists, so that the player can actually make a move. Otherwise the game is basically just not playable.
On the other hand, testing the view at all seems pretty fragile. Views are tricky in the sense that they have a tendency to change the most often and with the biggest changes, from my experience. That’s the beauty and purpose of the view: it is user-facing, it only presents an interface to the user. Thus, it is subject to constant scrutiny from a much larger array of team members; a manager may want the page to contain an ad on the bottom, the designer may want the sidebar placed on the left of the body instead of the right, the coder may realize that the
div with inner
divs should actually be a
ul with inner
lis. These constant changes by themselves can be a large burden, but adding the fact that for every change, the tests must also be changed, well, to me that indicates a potential nightmare may be on the horizon. Honestly, I’m just not sure I feel entirely comfortable with this aspect of TDD + MVC just yet.
On an unrelated note, this project has so far also been good practice in experimenting with Haml within a Rails app; it’s surprisingly straightforward: ERb is just translated to Haml, the files renamed to .haml, and then you’reall done. Granted it has a slight less flexibility than ERb does, but it’s awesomely more succinct, and the few times you need that flexibility, you can just drop down to ERb and problem solved. Overall, I think using Haml has been and will from now on be a huge win.
By the way, the most up-to-date version of the live app is usually hosted on Heroku specifically for your personal entertainment.
My name is Steven Degutis, and I've been writing software professionally for a decade. During that time, I've written many apps and websites, quite a few technical articles, and kept up-to-date with the rapidly evolving software industry.
If you have software needs for web, mobile, or desktop, and are looking for a seasoned software professional, please reach out to me at email@example.com to set up a phone call.
- Self-employed – present
- Clean Coders – 5 years
- 8th Light – 2 years
- Big Nerd Ranch – 1 year
- Self-employed - 1 year
- Web: full-stack
- iOS (UIKit)
- macOS (Cocoa)
- REST APIs
- AWS / EC2 / ELB
- HTML5 / CSS
Over the past decade, I've written a total of 172 technical articles on various programming languages, frameworks, best practices, and my own projects, as I kept up-to-date and active in the software industry.
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- 2017 — "Clean code" isn't actually clean
- 2017 — Passion in your field is overrated
- 2017 — What I learned in 5 days of writing an experimental website
- 2014 — Age of the Polyglot
- 2013 — How to Program
- 2013 — Ignore the Naysayers
- 2013 — Writing Clearly
- 2012 — Reinvent the wheel
- 2010 — Good usability
- 2009 — Twitter is the wrong tool
- 2009 — We're all pretty bad at driving
- 2008 — Why I Code
|August||NDD: Narrative Driven Development|
|August||The truth about TDD|
|August||Macroframeworks vs Microframeworks|
|March||Notes on Haskell Extensions|
|February||Second thoughts on front-end tools|
|February||First thoughts on front-end tools|
|February||Some thoughts on GUIs|
|February||First thoughts on OCaml|
|February||First thoughts on Haskell|
|August||Age of the Polyglot|
|August||The history of Mjolnir|
|August||Quitting the GUI wars|
|June||Lua: my new favorite extension language|
|January||My programming life-goals|
|January||Lingua Latina, Pars I|
|January||Allocating an AST on the stack|
|April||Ruby Accessors Considered Pernicious|
|March||Reinvent the wheel|
Here are some of the projects I'm most proud of. They were created using a variety of technologies, running on several different platforms and OSes. They're all finished products, and many of them are open source.
I made Docks in 2009 for users who wanted to swap out icons in their Dock with a single click. Its unique functionality and design aesthetic attracted the attention of Apple, Engadget, MacWorld, and led to an acquisition of my start-up by Big Nerd Ranch.
This toy was made in a weekend to entertain my 1 year old daughter. It lets you create bubbles with your fingers, which then simulate physics by bumping into each other and falling.
When I couldn't find an app in the App Store that let me make very simple lists extremely quickly, I made one myself. I use it almost every day to organize and track my activities.
I created this app to increase my productivity by letting me move windows around in macOS using keyboard shortcuts. It grew into a community-driven highly extensible app, using Lua for its plugin system.
Implementing this elite social network gave me experience integrating both Apple Pay and credit card payments (via Stripe.com) seamlessly into web apps, for a frictionless and pain-free payment experience.
This isn't just any chatroom. In this web app, you can see what everyone is typing while they type it. I made this in order to scratch my itch for making real-time apps and games, and learned how to use WebSockets in the process.
This was written in 2009, before the time of Slack, when IRC was the main way for programmers to get short-term assistance from each other. Its purpose was to be a beautiful app with an emphasis on simplicity and usability over technical power.
This is an app I actually use every single day. It lets you move windows with global keyboard shortcuts. Since it uses Vim-like key bindings, it should feel pretty natural to any programmer. There's no configuration needed; it Just Works™.
As an evolution of Phoenix, Hydra was my first attempt at embedding a full Lua virtual machine into an Objective-C app, to make a lightweight and efficient window manager that focused on speed, low memory usage, low CPU usage, and overall being gentle on laptop batteries.
These may be tiny, but they're interesting technical feats.
|Lua4Swift||Swift framework for embedding Lua with a native Swift API.|
|choose||Command line fuzzy-matching tool for macOS that uses a GUI|
|music||Command line music daemon for macOS that only speaks JSON|
|hecto||Command line text editor with an embedded Lua plugin system|
|ZephSharp||Window manager for Windows using Clojure for scripting|
|management||Minimalist EC2 configuration & deployment tool in Ruby.|
|go.assert||Assertion helper package for writing tests in Go.|
|go.shattr||Go library for printing shell-attributed strings to stdout.|
|OCDSpec2||Objective-C based testing framework with Xcode integration.|