TO START (run in Terminal):
cd ~/code/$GITHUB_USERNAME
git clone [email protected]:ajdubovoy/food-delivery-reboot.git
cd food-delivery-reboot
rm -rf .git
git init
code .We'll build a new challenge together, modelled on the concepts of OOP.
We'll start off with a short recap of the key concepts of OOP and Ruby classes, particularly focusing on the difference between a class and an instance, as well as a class method vs an instance method.
NOTE: There's no rake for this challenge. We'll review each piece individually together.
We'll try to do this before lunch together.
Today, we're going to build a multi-part app, focusing on restaurants. We'll build out all the pieces of the MVC patter together.
Define a class Restaurant in a new file app/models/restaurant.rb.
Our Restaurant model should have 3 instance variables:
@id@nameas aString@priceas anInteger. The price should be a number, ideally between 1 and 5 (it's like in Google Maps how it prints out "€" or "€€€€€").
Like in Food Delivery, the #initialize(attributes) should take one argument (an attributes hash). It should not take the id, name, and price as separate arguments.
Review with the teacher as a group.
Define a RestaurantRepository class in a new file app/repositories/restaurant_repository.rb.
It should have the following methods:
- An
#initialize(csv_file_path)method.- Should define a variable
@restaurantsthat is an array ofRestaurantinstances (this is the main purpose of a repository). - should store a
@csv_file_pathvariable that can be a String like"data/restaurants.csv". - Should call a
#load_csvmethod that opens the@csv_file_pathand fills up the@restaurantsArray with the restaurants that are already stored.
- Should define a variable
#all, which should return all the restaurants in the app.#find(id). When given anid(as an integer) it should return theRestaurantinstance with that id.
Please note that I've already filled out a data/restaurants.csv file for you with some sample data.
Review with the teacher as a group.
Now we'll dive in and build features in our application 🚀 Our goal for now is only to build this feature:
As a user, I can list all the restaurants
In order to build this feature, you will need to add a RestaurantsController class in a new file app/controllers/restaurants_controller.rb.
It should have the following methods:
- An
#initialize(restaurant_repository)method. - A
#listaction
The #list action in the RestaurantsController is where you'll need to implement your list code. Let's pseudo-code it together:
- Fetch all the restaurants from the repository
- Display them in a pretty list
To build step 2, we'll want to print some information, so you'll need a RestaurantsView!
In order to build this feature, you will need to add a RestaurantsView class in a new file app/views/restaurants_view.rb.
It should have the following methods:
- A
#display_list(restaurants)action
Review with the teacher as a group.
Finally, if we want to test out our list feature, we'll need to actually get our app up and running. To do so, we'll need to write 2 new files (they're already created, but they're just empty right now).
Let's code a new class Router in router.rb. This class should have a #initialize(restaurants_controller) that takes a RestaurantsController instance as an argument.
The Router should also have a #run method. This is the method that actually starts our application 🚀 It should:
- Start a loop (probably using
while) - Print out a menu to the user of all the options in our app, currently:
Press 1 to list all restaurants; Press 9 to quit - Ask the user to type in a number (from the menu).
- Run the correct corresponding controller action (or quit), depending on which number the user typed.
Now, we want to actually call our Router#run method and start our app! We'll want to write our app.rb file. It should create a new Router instance and "glue" all our files together.
When you run:
ruby app.rbin the Terminal, your application should start.
Review with the teacher as a group.
----------BREAK FOR LUNCH 🌮------------
Same format as Part 1, but we're going to add a new level of complexity.
Define a class Review in a new file app/models/review.rb.
Our Review model should have 4 instance variables:
@id@contentas aString. This is what the text of the review actually is.@ratingas anInteger. The price should be a number, ideally between 1 and 5 (it's like in Google Maps how it prints out "⭐" or ⭐⭐⭐⭐⭐"").@restaurantas aRestaurantinstance. This is the restaurant the review is written for. It should NOT be an integer, a string, a line in the CSV, anything else. It should be an instance of your existingRestaurantmodel.
Review with the teacher as a group.
Define a ReviewRepository class in a new file app/repositories/review_repository.rb.
It should have the following methods:
- An
#initialize(csv_file_path, restaurant_repository)method.- Should define a variable
@reviewsthat is an array ofReviewinstances (this is the main purpose of a repository). - should store a
@csv_file_pathvariable that can be a String like"data/reviews.csv". - Should call a
#load_csvmethod that opens the@csv_file_pathand fills up the@reviewsArray with the reviews that are already stored. How will you handle therestaurant_idcolumn?
- Should define a variable
#all, which should return all the reviews in the app.#add, which should add a new review to the app.- Should call a
#save_csvmethod that re-writes the CSV file (since we changed data and need to save it).
- Should call a
Please note that I've already filled out a data/reviews.csv file for you with some sample data. Definitely look at this file before beginning.
Review with the teacher as a group.
Now we'll dive in and build features in our application 🚀 Our goal for now is only to build this feature:
As a user, I can add a review for a specific restaurant.
In order to build this feature, you will need to add a ReviewsController class in a new file app/controllers/reviews_controller.rb.
It should have the following methods:
- An
#initialize(restaurant_repository, review_repository)method. - A
#createaction
The #create action in the ReviewsController is where you'll need to implement your list code. Let's pseudo-code it together:
- Fetch all the restaurants in the app from the repository.
- Display the user a numbered list of all the restaurants in the app.
- Ask the user to type the index of the restaurant they want to write a review for.
- Ask the user to type the content of their review.
- Ask the user to type a rating for their review.
- Take the information the user typed and build a new
Reviewinstance based on it. - Save that review to the repository.
To build steps 3-5, we'll want to print some information, so you'll need a ReviewsView!
In order to build this feature, you will need to add a ReviewsView class in a new file app/views/reviews_view.rb.
It should have the following method:
- An
#ask_for(stuff)method (or separate methods for asking for an index, a content, and a rating).
Make sure to add this new feature to your Router. How will this change the router.rb and app.rb files?
Review with the teacher as a group.
HARD CONCEPTUAL QUESTION:
Now, we want to actually see which reviews a restaurant has 🔍 But, it doesn't make sense to just list all the reviews in our app all at once.
Instead, we want to make it so that when you pick the existing "List all restaurants" menu item (RestaurantsController#list), it should show you the reviews like this:
1. Charlotte I (€€)
People said:
- (⭐⭐⭐⭐⭐) Amazing Place
- (⭐⭐⭐⭐⭐) So good
2. Chupenga
People said:
...
Do we need to add a new controller action to do this? How would it change the existing code?