I've now worked with a number of Turing students on the futbol project.
There's a few consistent spots that they tend to get stuck on, but I'm not familiar enough with the right solution to guide them to it.
Also, I've always enjoyed re-writing Turing projects. They usually take a tiny fraction of the time they took me in Turing, and I gain an appreciation for design patterns I've read about in books like Eloquent Ruby by Russ Owens (2011) and Sandy Metz' famous Practical Object-Oriented Design in Ruby, and of course Refactoring: Ruby Edition by Jay Fields.
I'm building this resource with goals and constraints in mind:
- share information in a way that advances the learning of a broad number of people, "beginner" through at least "intermediate".
- advance the related goals I've got described on intermediateruby.com/about
- do this quickly. for a variety of reasons, I'm working on "shipping quickly"
- advance the state of current Turing students who avail themselves of this resource, even if it's while they're doing the Futbol project
- be accessible enough that someone who isn't even in Turing could follow along, and probably gain some useful knowledge along the way. At minimum they'd get a laugh from at least one or two gifs ahead.
- Be "advanced" enough that someone who's about the level of a Turing grad a few months (or a year) out of Turing will still glean things of value.
- Exemplify design considerations expressed in the various Ruby books I have lying around.
- Learn some super useful things about exploring in Git how files evolve over time.
- Find opportunities for focused applications of Ruby/Object-Oriented Design best practices. I've no doubt I'll make some sub-optimal implementations, and in time (maybe weeks/months from now) I'll read about some refactoring pattern, and I'll find a way to implement it in this project.
- time, current knowledge
- I desire to "follow the path of most value", and I plan on this resource or a related resource to some day convey the kind of learning in a short enough time that people would plausibly spend non-trivial resources to learn more from.
- I've been typing for 10 minutes and I'm hoping to have at least some of this project done in the next 30 minutes
- My wife and I are pretty busy today. It's also relevant how much income I bring in. I'm a husband, future father, neighbor, homeowner, etc. I've got lots of competing demands on my time, and I hope to not waste your time that you might spend on this resource with me, no matter how you busy you are or are not.
- I'm open to sinking a dozen-plus hours into this guide (and I'm well on my way to that commitment) as long as the result is world class. Ideally, resources like this will lead to people like you, who work for companies that have external learning budgets, spending your money sponsoring more guides like this: https://github.com/sponsors/josh-works/. (If you dig this guide and don't have access to Other People's Money, consider sponsoring me at $1/mo. It's useful signaling behavior to me, makes it easier for me to rustle up corporate sponsors. Your $1/mo makes it easier for me to get $3k/mo from BIG_SOFTWARE_CORP down the road.)
_user's guide: this is a guide explaining how I've created Turing's futbal project from scratch. I've never done it before, I'll try to avoid making any leaps, but when I do lose you, please open an issue on this repo expressing as much. If you're not sure what that means, DM me in slack.
I'll outline my steps in stream-of-consciousness style, or as minimally-modified stream-of-consciousness as possible, from absolute scratch.
I'll include links to specific commits, so you can "follow along" this repo a bit better. I'll be starting from mkdir futbol and git init.
I use a today-i-learned repo, and as I work through the following resources, I'll update it and link to it in various ways.
https://github.com/josh-works/til/
I would advocate for almost everyone reading these words to use a resource like the above.
mkdir futbol
cd futbol
atom readme.md
This is what I've done for the above.
When pasting my git commands, I use my actual terminal commands, aliases included, because it'll reveal a slightly higher amount of information about how I work and patterns I use.
If at any point it get in the way of your learning, and I've either not explained it, or not explained it adequately, let me know and I'll clarify.
I'll commit it via:
git init
git status
ga .
gc -m "initial commit"
hub create
git lg
And the output:
* 4b3ca40 - (HEAD -> master) initial commit (2 minutes ago) <Josh Thompson>
https://github.com/josh-works/futbol/commit/4b3ca40
And you can figure out how to browse to the above commit in the repo (that's a whole sub-skill of itself I could talk about) and view the commit I just made checks watch 3 minutes ago from when I type these words.
The timing doesn't matter a lot, but it matters at least a little, in that the way code changes over time tells a story, had a purpose and meaning.
The speed at which a story unfolds adds meaning to the story, so inasmuch as the time I've spent working on this (and how that might correlate to how quickly you could do ("worse"|"the same"|"better")) has implications.
I just added the busy constraint in commit c7dc5d4 which adds some context.
https://github.com/josh-works/futbol/commit/c7dc5d4
I'll also be using screenshots throughout this guide, so I need a location to store the screenshots. you obviously don't need a screenshot directory.
And that'll be another commit. Obviously you don't need to be committing like this or anything. I just want to explain every step of my process, so if you check out the specific commits I list in the future, you'll be able to understand all the constituent pieces of what's gone into the application.
commit 5668ba1
https://github.com/josh-works/futbol/commit/5668ba1
I'll be using aliases for git commands. I've got them setup in my ~/.gitconfig, which currently contains:
# ~/.gitconfig
# This is Git's per-user configuration file.
[user]
name = Josh Thompson
email = thompsonjoshd@gmail.com
[alias]
co = checkout
hist = log --pretty=format:'%h %ad | %s%d [%an]' --graph --date=short
st = status
br = branch
lg = log --color --graph --pretty=format:'%Cred%h%Creset -%C(yellow)%d%Creset %s %Cgreen(%cr) %C(bold blue)<%an>%Creset' --abbrev-commit
[branch]
sort=committerdate
[push]
default = matching
[core]
editor = atom
excludesfile = /Users/joshthompson/.gitignore_global
# from https://tekin.co.uk/2020/10/better-git-diff-output-for-ruby-python-elixir-and-more
attributesfile = /Users/joshthompson/.gitattributes
[color]
ui = true
[difftool "sourcetree"]
cmd = opendiff \"$LOCAL\" \"$REMOTE\"
path =
[mergetool "sourcetree"]
cmd = /Applications/Sourcetree.app/Contents/Resources/opendiff-w.sh \"$LOCAL\" \"$REMOTE\" -ancestor \"$BASE\" -merge \"$MERGED\"
trustExitCode = true
[blame]
# coloring = repeatedLines
coloring = highlightRecent
The above committed in 1f15647
https://github.com/josh-works/futbol/commit/1f15647
OH! Forgot to mention... I'm about 20 minutes into beginning this project, 2021-03-02. Most of that time has been writing the above "outline" of everything. After the last commit on march 2, I was out of the house for the evening, having a covid-safe outdoor dinner with some friends in Denver.
The commit logs will show "wall time" that's elapsed as I've completed this project, but I'll be carefully tracking how much time I spend actually implementing this project. So far, we've not really begun any implementation besides setting up an empty git repo, adding a readme.md, and a folder for images.
Back to the futbol spec, under iterations: https://backend.turing.edu/module1/projects/futbol/index
Iteration 1: Setup and File I/O
Click the link to iteration 1: https://backend.turing.edu/module1/projects/futbol/iterations/file_io
The steps are:
- One team member forks the repository here and adds the other(s) as collaborators.
- Each of the other team members accepts the invitation to collaborate and then clones the repository.
- Setup SimpleCov to monitor test coverage along the way.
- Create a Rakefile that will run each of your test files without having to run them individually. See this lesson plan for more details.
I'll be skipping the Rakefile and Simplecov step for now. If you're following this guide, do the same. Both of those are worth learning, and setting up, but later, not now.
OK, the File I/O section... is so barebones.
I'm going to take a break from this (because the instructions are junk) and take a tour through... CSV Exploration
go read the REALLY LONG README I wrote in the /csv_exploration_lesson directory. It's long, detailed, full of screenshots and useful learnings, and sets the stage for the futbol lesson.
Much of what I'll cover in the next few hours will be at least partially based on learnings from that lesson, and your own learning outcomes will be vastly improved if you explore that lesson for yourself.
Even if you don't complete it in the same way or to the same degree that I do, you'll be better off for the exploration
Did you spend a few hours working through the above CSV Exploration README? Take a look at the class that I built, in order to make it all pass: https://github.com/josh-works/futbol/blob/master/csv_exploration_lesson/name.rb
If there's a lot in there that is unintelligble to you, you might not be ready to move to the Futbol project.
Take a look at the file (and how it evolved over time) in git history
You'll get a feel for how software evolves. It's worth understanding!
Consider yourself warned...
add a .keep to the inside - that lets the file get added to git and you can commit it: ea02997
https://github.com/josh-works/futbol/commit/ea02997
Download the CSVs, place them in a data directory.
It's tricky to get these files. You can download their directory using this github file downloader
Unzip the file, figure out how to get them in your data directory:
$ lr ~/Downloads | tail -10
-rw-rw-rw-@ 1 1.0M Feb 27 11:47 stendahl1963.pdf
-rw-rw-rw-@ 1 1.0M Feb 27 11:47 stendahl1963(1).pdf
-rw-rw-rw-@ 1 78K Feb 27 12:06 qGhC3pM2.rss
-rw-r--r--@ 1 98K Feb 27 14:44 .DS_Store
-rw-rw-rw-@ 1 19M Feb 28 18:33 The Needful Annihilation -Mark 8.mp3
-rw-rw-rw-@ 1 2.5M Mar 1 14:29 bloom-two-sigma(2).pdf
-rw-rw-rw-@ 1 76K Mar 1 17:27 Benefit-Summary-Red-Canary.pdf
-rw-r--r--@ 1 1.6M Mar 4 14:10 turingschool-examples futbol main data.zip
drwx------@ 734 23K Mar 4 14:10 .
drwxr-xr-x+ 162 5.1K Mar 4 14:16 ..
That bottom file is the one we want!
$ mv ~/Downloads/turingschool-examples\ futbol\ main\ data.zip ./data
# tab complete is a lifesaverHere's what it looks like:
lr in my terminal is aliased to "ls the files, but [R]everse the order based on most recently updated"
The bottom entry, when calling lr is always the newest/most-recently-changed file/directory. It's quite handy.
unzip the file. I know there's an unzip utility, not sure how to use it, so looking it up in tldr:
then delete the zip.
Now you've got the data in your data directory. Open up the CSVs, think about them for a minute.
you can do open data/game_teams.csv to open the CSV up in your local CSV-reading application.
This is the "hint" you get next:
# runner.rb
require './lib/stat_tracker'
game_path = './data/games.csv'
team_path = './data/teams.csv'
game_teams_path = './data/game_teams.csv'
locations = {
games: game_path,
teams: team_path,
game_teams: game_teams_path
}
stat_tracker = StatTracker.from_csv(locations)
require 'pry'; binding.pryThis is a big leap. I mean... it makes some sense to me, but it's a rough way to start the project.
Why not try running it? I know it's not going to work, we've not created the StatTracker class, nor written a from_csv method.
So, lets do that...
create base class: https://github.com/josh-works/futbol/commit/8b736b5
create runner file: https://github.com/josh-works/futbol/commit/e951634
run it:
ruby runner.rb
From: /Users/joshthompson/me/projects/futbol/runner.rb:16 :
11: game_teams: game_teams_path
12: }
13:
14: stat_tracker = StatTracker.from_csv(locations)
15:
=> 16: require 'pry'; binding.pry
main:0> stat_tracker
=> nilCool.
And now the instructions say:
::from_csvreturns an instance of StatTracker. That instance ofStatTrackerwill hold all of the information you need for the methods included in the remainder of the project description.
hm. The only next step is: https://backend.turing.edu/module1/projects/futbol/iterations/statistics
Which doesn't talk much about how to set this thing up.
So, I'll take a minute to think about it. I need to read ahead and see what might be expected for the application down the road.
For starters, I know I'm going to need:
- A model with column-referencing attributes, so I can call something like
game.date_timeand get back the date/time for that particularGameinstance.
Based on the CSV lesson we just did, I'll probably want to call methods on instances and their classes. Something like:
Games.all
Games.order_by(:date_time)
game.teams
game.home_goalsetc.
Of course I'll need to write tests against those classes, because the non-TDD way I did the CSV lesson was so painful and difficult. We'll use real-world test-writing, and use it in such a way that it makes our lives dramatically easier.
I don't have to worry too much about the long-term growth of this application, since I know at minimum a little about the stuff I'll do with Games. I'll just set that up next time I sit down, and I'll share the progress with you.
https://github.com/josh-works/futbol/commit/9cfae08
OK, outlined an idea game class, based on the first row of game.csv. I'm just making on attribute for every column.
I'll feed the data in probably as a comma-separated list, for now, so I'd call (again, copying now the 2nd line of the CSV):
"2012030221,20122013,Postseason,5/16/13,3,6,2,3,Toyota Stadium,/api/v1/venues/null"
data = "2012030221,20122013,Postseason,5/16/13,3,6,2,3,Toyota Stadium,/api/v1/venues/null".split(',')
Game.new(data)Here's what I've got... lets get it to run!
oh, yeah, requires are wrong. Lets peek at some existing test file somewhere...
And added a little front-matter in commit https://github.com/josh-works/futbol/commit/3a64799
OK, test runs, now it gets an error, which... is to be expected.
(by the way, we're starting with some naïve initialization in a moment, I'll refactor down the road, according to the amazing book Practical Object Oriented Design in Ruby).
And the test passes:
https://github.com/josh-works/futbol/commit/4494178
Break time for me! Been a long day. I'm glad that I'm finally getting to write some of the code on this project, though!
So, picking up with fleshing out the Game class.
Already, I know I'm going to want to improve the initialization process. It's quite fragile right now, but I'll let future design considerations drive updates to the initialization method.
For now, I know that when I create a new game instance, I can call:
game.away_team_idand get back an integer, like 15. That's the ID of an entry in teams.csv
I don't want to just be passing around integers, I want to be able to get the actual team.
So, I'll figure out how to be able to do:
game.away_teamand it'll return an instance of the Teams class, corresponding to the underlying team.
Before doing this, of course, I'll need a bare Teams class, and an associated test. For now, though, I'm going to write an "aspirational" test in my Game class that guides me in the right direction:
def test_away_team_returns_a_team_object
assert_instance_of Team, @game.away_team
endThis fails, of course... do you know why? Take a moment, think, why does this test fail, and what specific error message will it generate?
answer: uninitialized constant Team. Lets make it pass, but along the way, we'll start a team_test.rb file too.
https://github.com/josh-works/futbol/commit/4b2f7bd
Adding a test - notice how I'm using data in the setup method - that string (critically) ends with "".split(","), which allows me to take the first row of data from the teams.csv, copy-paste it in here, and split it into an array, ready to be "consumed" by my initialization method.
This new test passes: https://github.com/josh-works/futbol/commit/325feec
So, back to my Game class, to figure out how to get game.home_team to return a Team instance.
Currently, running the test, I get Uninitialized Constant Team. Let's add another require statement, but this time we're going to introduce a "test helper" file. This file will contain all necessary require statements and gems, and we'll simply require it from each additional test file we might create. Go look at this specific commit:
https://github.com/josh-works/futbol/commit/c62ddd4
It'll save you a lot of hassle down the road. This also solves our Uninitialized Constant problem - now we're getting undefined method, because there is no away_team method. Lets add it:
def away_team
# ??? What goes here???
endWe want a Team object back, and based on the CSV lesson we just did, we know we could do something like Class.find(id) and expect to find an instance of that class, with that ID.
How might you write this?
I used:
def away_team
Team.find(away_team_id)
endRemember - this isn't going to pass this test at all! I've not created a Team#find method on the Teams class, but I know I have an away_team_id available to this Game class, so... I'm good with this. I'll let this method drive me back towards writing code in the team class...
When I run the tests, I get:
NoMethodError: undefined method `find' for Team:Class
https://github.com/josh-works/futbol/commit/b5ef633
I added this test:
def test_find_class_method_finds_team_by_id
assert_instance_of Team, Team.find(1)
endObviously, again, it fails because I've not made it pass yet, but it tells me where to go.
I don't know that a team with that ID exists, but I think it does, because of the data I'm feeding in on the setup. The id looks like 1, so I'm going to expect this method to return that particular instance of a Team, eventually.
Here's what I wrote in my find method:
def self.find(id)
all_teams.find {|team| team.id == id }
endyou might say:
Josh, where'd that
all_teamsthing come from?
Good question. I've not written the method yet. When I run the tests, it'll throw an error about "all_teams", so lets add a test for all_teams, and make it pass... (all the while, this test I just wrote, and the test in my Game class are still failing, this is fine, to be expected.)
I've renamed it, I'm going to do Team.all (class method) instead of all_teams (a different class method).
[...]
OK, we're getting a little complicated, writing a lot of small methods. Try to stick with me...
Here's where I'm at:
https://github.com/josh-works/futbol/commit/01b8a0d
I have to figure out how to load up all my teams data. I am making a "private class method", that looks like so:
Now's a great time to flip to name.rb in that CSV exploration lesson for inspiration...
I wrote out:
def self.load_teams_data
rows = CSV.read(@@filename, headers: true, header_converters: :symbol)
rows.map do |row|
Team.new(row)
end
endLets run the tests, see how it looks.
Ah, it needs the CSV class. I'll add a require 'csv' to the top of the file, though if you suspect we'll be using a helper file to handle all our requires soon... you'd be correct.
Here's the current state of things: https://github.com/josh-works/futbol/commit/8feb80d
When I run the tests, I have a failure and an error.
Here's the failures:
$ ruby test/team_test.rb
Run options: --seed 60717
# Running:
FE.
Fabulous run in 0.002825s, 1061.9469 runs/s, 2477.8761 assertions/s.
1) Failure:
TeamTest#test_find_all_returns_all_teams [test/team_test.rb:25]:
Expected: 1
Actual: 32
2) Error:
TeamTest#test_find_class_method_finds_team_by_id:
NoMethodError: undefined method `id' for #<Team:0x00007fb4eb12cd78>
/Users/joshthompson/me/projects/futbol/lib/team.rb:24:in `block in find'
/Users/joshthompson/me/projects/futbol/lib/team.rb:24:in `each'
/Users/joshthompson/me/projects/futbol/lib/team.rb:24:in `find'
/Users/joshthompson/me/projects/futbol/lib/team.rb:24:in `find'
test/team_test.rb:20:in `test_find_class_method_finds_team_by_id'
3 runs, 7 assertions, 1 failures, 1 errors, 0 skips
Now - I want you to take a moment and think about this, especially if you're getting the same errors.
In some ways, this is exactly what I expected, and is easily fixed. In other ways, it's also telling me I mis-labeled some things. It's not a problem, but it's easily fixed.
I'm now loading 32 teams, not 1, so my assertion on line 25 is coming back as 32 instead of 1. (This is a good thing!)
and I don't have a team.id attribute, I have a team.team_id attribute. Update the code and... my find is still broken.
Ah, it's because I'm saving team_id as a string, not an integer.
These are different:
"1"
1
I'll update my initialization method to convert the team_id to an integer, and all passes:
https://github.com/josh-works/futbol/commit/52a2f44
Lets try my other test, see how that looks...
[...]
Ah, I need to coerce all id-like bits of data to an integer. I'll go ahead and update the tests and initialize to convert more stuff to integers... and the tests pass:
https://github.com/josh-works/futbol/commit/8978149
Now lets add a home_team method (and test) and we're doing fine. Tests still pass.
https://github.com/josh-works/futbol/commit/7f75e86
Now that we have two test files, while we often want to run a single test file, it would be nice to easily run all of our test files, to make sure we didn't break something in another test file.
We could run it manually like:
$ ruby test/game_test.rb
# check results
$ ruby test/team_test.rb
# check resultsThat's a lot of typing, especially as the tests add up.
In the repository it was expected that you use as a base for this project (I didn't, built it from scratch) there's a Rakefile. Check it out:
https://github.com/turingschool-examples/futbol/blob/main/Rakefile
Bring that Rakefile over to your current project. The filename is Rakefile (not rakefile, or Rakefile.rb), and copy/paste that stuff into it. Now, in your terminal, type rake and it runs all your tests. rake and rake test are the same.
Here's how usage looks:
added it in this commit: https://github.com/josh-works/futbol/commit/ef93f3b
OK, next, even without looking at much other stuff in the spec, I know I'll want to know who won a particular game.
If I have a game instance, I need to be able to call game.winner and get a Team instance back. Bonus points if that team happens to be the winner for that game. (brilliant, right?)
So, I'll write out a test in game_test.rb, and let that drive me towards dealing with this game_teams.csv... stuff.
Outlined my (failing) test here: https://github.com/josh-works/futbol/commit/24d447f
Now lets build a game_teams model. I'll need to be able to say, at minimum, something like:
def winner
GameTeam.winner_of_game(game_id)
endand get back a Team object.
Lets go build GameTeam!
(BTW, I know I'm going to need a Class.all method for Game. You can build your own implementation of that now if you want. There's no "exactly correct" order to how to do all this.)
So, outline my test, same as before. Update my test_helper to reference my new game_team class, and we have a passing test. https://github.com/josh-works/futbol/commit/ecd0275
A little more cleanup, anytime I have an _id attirbute, I can just coerce that string to an integer. In fact, most attibutes of GameTeam are integers (except for #face_off_win_percentage needs to be a Float), so lets do that...
Update tests, update code, test still passes in commit https://github.com/josh-works/futbol/commit/ecf890f
Back to trying to make... which test pass again?
I know I have a failing test. I don't even remember what class it was in, though I could figure it out. Instead I'll run rake, to run all tests, and see which one(s) fail.
OK, I need a winner_of_game method that takes a game_id and returns a Team object that represents the winner of that game...
ooooh, crap. I don't need to call out to GameTeam from my Game class, the game knows who the winner is, based on the home_goals and away_goals. I can do logic on self and return the winning team....
here's what I aspirationally typed into my Game#winner method:
def winner
# GameTeam.winner_of_game(game_id)
return away_team if away_team_won?
return home_team if home_team_won?
endthose away_team_won? and home_team_won? methods have not been written yet.
OK, a little more code (lots of small, clearly-labeled methods) and we've got passing tests. Note the use of private, which denotes "these methods are not being tested". Saves me time of having to write more test code, and since these methods will never be "public" to other classes, it's... OK... to not test them. (er, this is a hot take, some people may strongly disagree. You're welcome to write this code however you want!)
Why not add a loser method too, just for completeness. I could see it making code more readable!
https://github.com/josh-works/futbol/commit/cce5fd0
now... I want to refactor this code a little.
Because I've used ActiveRecord, a lot, I'm a fan of being able to call id on objects and just... get their id back. Here's how to do that, without adding much code at all:
Here's what it looks like:
And the commit: https://github.com/josh-works/futbol/commit/afbeca3
Let's take a look at the spec. I've not looked in a while. I could "garden" a bit more here. For example, I'll probably need the following methods:
GameTeam.all
GameTeam.find(game_team_id)
Game.all
Game.find(game_id)
Team.all
Team.find(team_id)This is a good spot to use a Module to enable this funcionality across all three classes without duplicating a bunch of code. I'll go ahead an add this, so you can get a feel for how it could work. First, lets add tests to all three classes that prove that this functionality will exist.
I've added failing tests here: https://github.com/josh-works/futbol/commit/6ac30c6
I already have this method in the team_test class, so I didn't add anything there.
OK, refactored to use a module for Team#find. Took a minute of Googling to figure out how to include the module on line 5 in such a way that I stopped getting a method not found error for Team#find. Team "Extends" Finder, per Add class methods and instance methods to class by including one Module
commit: https://github.com/josh-works/futbol/commit/ddcb7a7
Lets extend this functionality to other classes now:
When I run rake I get:
Run options: --seed 19617
# Running:
.........E.E.
Fabulous run in 0.002867s, 4534.3565 runs/s, 14300.6627 assertions/s.
1) Error:
GameTest#test_find_returns_game_by_id:
NoMethodError: undefined method `find' for Game:Class
/Users/joshthompson/me/projects/futbol/test/game_test.rb:50:in `test_find_returns_game_by_id'
2) Error:
GameTeamTest#test_find_returns_game_team_by_id:
NoMethodError: undefined method `find' for GameTeam:Class
/Users/joshthompson/me/projects/futbol/test/game_team_test.rb:32:in `test_find_returns_game_team_by_id'
13 runs, 41 assertions, 0 failures, 2 errors, 0 skips
As expended, no find method available there. But I've got a module that has this method!
Now I've got no access to a method all for the class, so I'm going to add that to finder too....
OK, a bunch of code just happened. I undoubtedly made some leaps. Read the commits carefully. I've got a working version that passes all tests here:
https://github.com/josh-works/futbol/commit/e944702
and refactored some more...
https://github.com/josh-works/futbol/commit/eeb2df4
OK, there's a ton of StatTracker methods we seem to need to do.
Let's take a stab at just outlining the very first method, beginning-to-end, with tests and such...
Game Statistics:
highest_total_score | Highest sum of the winning and losing teams’ scores | Integer
OK. And they should be instance methods, not class methods.
I'm continuously trying to write "aspirational" code, so here's what I have in my StatTracker class. Notice that I don't have a GameStats class, and it certainly doesn't have the given method on it.
require './helper'
class StatTracker
def self.from_csv(locations)
end
def highest_total_score
GameStats.highest_total_score
end
endBut... I can create that class, and it can probably interface with my Game class fairly nicely.
OK, bunch of futzing around. Messing with requires, to keep my code well-organized.
I've got a passing test (the first one) for my GameStats class:
https://github.com/josh-works/futbol/commit/ca21d0d
and refactored a bit more to make all tests pass, with the usage of rake:
https://github.com/josh-works/futbol/commit/ea56f01
So, I have to use this spec harness to provide external evaluation of my code.
It can be a total PITA to set up, so let me walk you through it...
cd .. # this gets you one directory "up" from your `futbol` repo
git clone
git@github.com:turingschool-examples/futbol_spec_harness.gitNow when you ls you should both futbol_spec_harness and futbol directories
cd futbol_spec_harness
atom . # to explore it, just for the heck of it.
bundle # installs all dependenciesRun the tests with:
rspecNow, it failed, all over the place. No sweat, I have to change require statements in my futbol repo.
It better not eff with my tests I'm running locally....
Everywhere I have the following:
require './lib/...'
I'll change it to require_relative ./...
Commit showing the changes: https://github.com/josh-works/futbol/commit/8b0c1a7
Sigh. So frustrating. I'm losing a lot of time trying to make both my local tests and the spec harness run without errors.
Here's how I'm running the test:
$ rspec spec/stat_tracker_spec.rb:22Appending :22 to the command says run just the test on that line, greatly reduces the output I have to scroll through.
TONS of uninitialized constant errors.
I guess I'll just bite the bullet on the circular loading error, and accept the successful RSPEC output.
Here's the commit: https://github.com/josh-works/futbol/commit/51d564d
So, I'm comfortable with my basic setup. I'll have my StatTracker make calls to GameStat class methods, and in the GameStat class I'll do the heavy lifting.
I'll write tests for all of it, and yes, it's a bit annoying that I'm kinda "duplicating" the tests in StatTracker and GameStat. I think we'll find out quickly that this is still a helpful process, so bear with me as I do it.
Lemme brag on some copy-paste-terminal goodies.
I just copied-pasted the table from the spec into named-and-ready-to-go test methods, en-mass.
I got from here:
lowest_total_score Lowest sum of the winning and losing teams’ scores Integer
percentage_home_wins Percentage of games that a home team has won (rounded to the nearest 100th) Float
percentage_visitor_wins Percentage of games that a visitor has won (rounded to the nearest 100th) Float
percentage_ties Percentage of games that has resulted in a tie (rounded to the nearest 100th) Float
count_of_games_by_season A hash with season names (e.g. 20122013) as keys and counts of games as values Hash
average_goals_per_game Average number of goals scored in a game across all seasons including both home and away goals (rounded to the nearest 100th) Float
average_goals_by_season Average number of goals scored in a game organized in a hash with season names (e.g. 20122013) as keys and a float representing the average number of goals in a game for that season as values (rounded to the nearest 100th) Hash
to here:
class GameStatsTest < Minitest::Test
def test_highest_total_score
assert_equal 11, GameStats.highest_total_score
end
###############################
# GAME STATISTICS #
###############################
def test_lowest_total_score
# Lowest sum of the winning and losing teams’ scores
# => Integer
end
def test_percentage_home_wins
# Percentage of games that a home team has won (rounded to the nearest 100th)
# => Float
end
def test_percentage_visitor_wins
# Percentage of games that a visitor has won (rounded to the nearest 100th)
# => Float
end
def test_percentage_ties
# Percentage of games that has resulted in a tie (rounded to the nearest 100th)
# => Float
end
def test_count_of_games_by_season
# A hash with season names (e.g. 20122013) as keys and counts of games as values
# => Hash
end
def test_average_goals_per_game
# Average number of goals scored in a game across all seasons including both home and away goals (rounded to the nearest 100th)
# => Float
end
def test_average_goals_by_season
# Average number of goals scored in a game organized in a hash with season names (e.g. 20122013) as keys and a float representing the average number of goals in a game for that season as values (rounded to the nearest 100th)
# => Hash
end
endWith just multi-cursor movement. Consider doing the same. It's helping me organize my tests very cleanly.
Here's what I've got, as I've finished outlining the tests. I'm not committing to any of them, but it will help me know where I'm going.
commit https://github.com/josh-works/futbol/commit/d232113
Next session. In the last few days I realized I want to do away with this GameStats class (I think) and work on building up Game query methods.
So, I've done that in this commit:
https://github.com/josh-works/futbol/commit/c0fa719
More complexity. I think I'd like to be able to do something like this:
Game.where(winner: :home)
Game.where(winner: :away)and, well, get the games where the winner was the home team. Seems like this would be handy, right? We can probably imagine ways of upgrading the value of the queries, and as long as we can make this work how we want, this will be a useful tool to have down the road.
To this end, here's the test I wrote:
def test_where_home_won
assert_equal 144, Game.where(winner: :home)
endAnd here's my attempt at making it pass. I've not run the test yet, I know for a fact this is going to blow up:
def self.where(query)
key = query.first
value = query.last
Game.select do |game|
game.send(key) == value
end
endLet's find out!
OK, didn't quite work as written, minor updates:
def self.where(query)
key = query.first[0]
value = query[key]
Game.all.select do |game|
game.send(key) == game.send(value)
end
endOK, now that this method works (I wrote model tests for my Game class, along with a helper method or two.)
Commit:
https://github.com/josh-works/futbol/commit/ec325f5
Story time: I've got these two methods:
def winner
return away_team if away_team_won?
return home_team if home_team_won?
end
def loser
return away_team if !away_team_won?
return home_team if !home_team_won?
endThose call out to:
def away_team_won?
away_goals > home_goals
end
def home_team_won?
home_goals > away_goals
endSee the problem?
This doesn't handle ties. What if both teams scored 3?
I need to set up a test that lets me set up a game where both teams scored 3. Here's how I'm setting up a team right now in my test:
data = "2012030221,20122013,Postseason,5/16/13,3,6,2,3,Toyota Stadium,/api/v1/venues/null".split(',')
@game = Game.new(data)Which one of those numbers do I need to update to get a game with no winners?
Damned if I know. I went and looked at the games.csv data, tried counting, etc, it was ugly. Here's how I want to be able to set up my game:
data = {
game_id: 2012030221
,season: 20122013
,type: "Postseason"
,date_time: "5/16/13"
,away_team_id: 3
,home_team_id: 6
,away_goals: 2
,home_goals: 3
,venue: "Toyota Stadium"
,venue_link: "/api/v1/venues/null"
}
@game = Game.new(data)See, because now I could specify the exact values I want for goals, quite easily.
I remember reading something in Practical Object-Oriented Design in Ruby about this...
Found it. Page 49: Write Loosely Coupled Code: Isolate Multiparameter Initialization. Sandi Metz says if you're stuck relying on order-dependent object initialization, write a wrapper that takes a hash and makes a call to Class.new with the parameters correctly written.
So, what we'd do is something like this:
class GameMaker
def self.new(data)
Game.new(
game_id: data[:game_id],
season: data[:season],
type: data[:type],
home_team_id: data[:home_team_id],
away_team_id: data[:away_team_id],
home_goals: data[:home_goals],
away_goals: data[:away_goals]
)
end
endetc. Then, you could use it like:
data = {
home_goals: 3
away_goals: 4
}
GameMaker.new(data)
=> # a new game instanceLet's take a stab at doing that. Mostly because its a good chance to practice building a wrapper around an inflexible interface (order-dependent initialization) and making it a more flexible interface (keyword-based object initialization).
Cool, it works:
This now allows me to do something like:
GameMaker.new(home_goals: 3, away_goals: 4)And I'll get a Game object with those values set. (Everything else will be nil, which is fine, for testing purposes.)
This lives in commit: https://github.com/josh-works/futbol/commit/0150cca
For evidence that this is working, here's the test that fails, using my Game initialization method:
def test_when_no_winner
data = {
home_goals: 3,
away_goals: 3
}
game = Game.new(data)
assert_equal 3, game.home_goals
assert_equal 3, game.away_goals
assert_nil game.winner
endAnd notice now using GameMaker, and it passes:
def test_when_no_winner
data = {
home_goals: 3,
away_goals: 3
}
game = GameMaker.new(data)
assert_equal 3, game.home_goals
assert_equal 3, game.away_goals
assert_nil game.winner
endThis GameMaker pattern might help me down the road, as it'll allow me to initialize Game objects (and Team objects with a TeamMaker, etc) in a flexible way, which will make my test writing vastly easier.
Oh, and I did this, to turn off all the circular loading warnings whenever I ran rake:
diff --git a/Rakefile b/Rakefile
index f37b89d..04a551b 100644
--- a/Rakefile
+++ b/Rakefile
@@ -2,6 +2,7 @@ require 'rake/testtask'
Rake::TestTask.new do |t|
t.pattern = "test/**/*_test.rb"
+ t.warning = false
end
task default: ["test"]Inspired by If you just want to turn off the warnings, you can do so in the rake test task setup:
https://github.com/josh-works/futbol/commit/2541639
OK, lets finish up Game Stats. I think when we move to other kinds of stats, it'll get far more interesting.
I had to update my self.where query to handle the way I wanted this method to work. To find all ties, I should be able to say
find all Games where
winnerisnil
At least, that's how I decided to do it.
So, that meant a query like:
Game.where(winner: :nil)That required an if/else statement in my Game#where query, otherwise I was getting game does not respond to nil, which is, in fact, true. game.nil doesn't make sense, but game.nil? totally does.
Anyway, I then had to update my #winner and #loser classes, because I wasn't actually testing for a tie, just win/losses.
Updated my tests a bit, too. They might be not-great. It would be nice to have Factories set up. I need a kinda-sorta valid Team to create a valid Game. There's something in Sandi Metz book about mocks/stubs, I'll look those up later.
Current commit, with the above refactoring:
https://github.com/josh-works/futbol/commit/1c77554
Seems like a simple group_by, but I'm thinking I might also want to later create a Season class, so I could do something like:
Season.alland get something like:
{ id: [game_1, game_2],
id: [game_3, game_4] }
NVM, I'm going to use a lot of Season stuff down the line. Let's make a Season class.
Here it is:
https://github.com/josh-works/futbol/commit/793e9a7
Now, that gives me Season instances that respond to id and games.
I still want Season.all to work, so let me add a test and make it pass.
Did that here:
https://github.com/josh-works/futbol/commit/5a2d703
Now, lets do count of games by season. That'll be simply iterating through our Season objects with Season.all.each and calling games.count on each season.
I've got it done here:
https://github.com/josh-works/futbol/commit/5e1e6f2
Adding a query method.
Maybe I'll end up doing something different. I thought of a where-esque kind of solution, but, meh. This is quick and easy.
https://github.com/josh-works/futbol/commit/f010060
This doesn't feel like very meaningful information.
I have a Season.all method, so I can map through them, and do an inject for games.total_score and then divide that with games.count? Hm.
I'm skeptical, but I don't see a different way to do it.
note to the reader. 4 months elapsed from me writing the above line, and the following. I wanted to come back to this project and finish it up, so I'm not moving forward with very, very low recollection of this entire project. This is a common phenomina that you'll encounter on the job. You'll do some work on a system, and then forget about it for months, and then need to come back and pick it up again. This isn't a problem, don't be discouraged, it's normal.
... looks like this was a good strategy.
And all the work for this method is visible in
https://github.com/josh-works/futbol/commit/d7ea53f
OK, we know we'll need to be able to call StatTracker#count_of_teams, so I'm outlining a basic version of that test:
def test_count_of_teams
assert_equal 22, @st.count_of_teams
# i just made up the 22. I have no idea how many teams we've got.
endOoooh, we've got all these Team things in the data. I just looked at teams.rb again, and because of the importing I'm seeing:
class Team
extend Finder
extend DataLoaderI think Team.all will return an array of all team objects.
So, my stat tracker method is amended to:
def count_of_teams
Team.all.count
endand I rerun my test. Looks like we have 32 teams instead of my guess of 22, so I'm going to update the spec.
https://github.com/josh-works/futbol/commit/7362eb9
The spec says:
Name of the team with the highest average number of goals scored per game across all seasons.
OK. So, we're going to ask our Teams a question that will require teach team to generate it's goals-per-game for all seasons.
Something like Team#avg_goal_per_game_all_seasons. Then we'll do a max_by in our query method. The stat tracker method will look like:
Teams.all.max_by(:avg_goal_per_game_all_seasons).nameand that should give us the name of the team. Lets make this work. What's our rough process?
- Write a failing test in the
stat_tracker_testfile - write the outline of that method in the
stat_trackerfile - Write a failing test in the
team_test.rbfile - make the method past in
team.rb - Use this new method from the
stat_trackerclass - Everything passes?
So, I've got failing tests, but I still don't understand the requirement.
A team has an average goals per game across all seasons.
Like.... 2.48?
Anyway, here's the commit. Tests are failing, but I'm moving in an OK direction I think: