Pet App!
Overview
Track owners and pets!
Objectives
Practice:
- validations and error handling
- associations (one-to-many)
Getting Started
- Fork this repo, and clone it into your WDI class folder on your local machine. Change directories into the project directory.
- Run
bundle
in the Terminal to install gems from the Gemfile. (Feel free to take a look at what's included, first.) - Run
rails db:create db:migrate
in the Terminal to create your local database and run the migrations. - Run
rails s
in the Terminal to start your server. - Navigate to
localhost:3000
in the browser - you should see a genericsite#index
page. - Run
rails routes
to see what routes are available in the app. - Run
rails notes
to see some of the things you'll do with this app
Sharing
When you're finished working on the pet app:
- add a 3-5 sentence reflection on this app to the top of your readme
- push your work to the master branch of your GitHub fork
- add a link to your repo on the "My Work" section of your website
Part 1: Owner Validations and Error Handling
Add Model Validations
-
Run
rspec spec/models/owner_spec.rb
from the Terminal to see the tests that are set up for theOwner
model. -
Add validations to the
Owner
model. Owners have the following restrictions:
- owners are required to have a
first_name
, alast_name
, and anemail
- an owner's
first_name
,last_name
, andemail
must each be at most 255 characters long - emails must be unique; that is, no two owners can have the same
email
- emails must contain an
@
symbol (hint: this checks theformat
)
See the Active Record Validation guide for guidance.
- In the Terminal, open up the Rails console, and try adding an invalid owner to the database using the
.create
method:
irb(main):001:0> guy = Owner.create({
irb(main):001:1> first_name: "Guybrush",
irb(main):001:2> last_name: "Threepwood"
irb(main):001:3> })
What happens?
-
Now try storing the invalid owner in memory with the
.new
method, and check if it's valid:irb(main):001:0> guy = Owner.new({ irb(main):001:1> first_name: "Guybrush", irb(main):001:2> last_name: "Threepwood" irb(main):001:3> }) irb(main):001:4> guy.valid?
-
Still in the Rails console, use
.errors.full_messages
to display the user-friendly error messages for the invalid owner you just created.
Refactor Controller to Handle Errors
- The
owners#create
method currently looks like this:
#
# app/controllers/owners_controller.rb
#
def create
owner = Owner.create(owner_params)
redirect_to owner_path(owner)
end
The
owner_params
method is set up to use Rails strong parameters.
What happens when you navigate to localhost:3000/owners/new
in the browser and try to submit a blank form?
Refactor your owners#create
controller method to better handle this error. Hint: Use .new
and .save
.
Hint: which methods to use?
Try `.new` and `.save` so it's easier to see if there's an error.Hint: what to do if there's an error?
For now, redirect back to the page with the form. If you don't remember the path helper method to use, `rails routes` in your Terminal and check the prefixes!- Once you've refactored
owners#create
to redirect in the case of an error, add flash messages to show the user the specific validation error they triggered, so they won't make the same mistake twice.
Hint: where to set the flash message?
Set the flash message in the controller by adding the message into the `flash` hash. The `flash` hash is special short-term memory in Rails that lasts just until the end of the *next* request - which makes it perfect to use with redirects! (See the [Rails Flash message guide](http://api.rubyonrails.org/classes/ActionDispatch/Flash.html) for syntax.)Hint: where to display the flash message?
Create a place to render the flash message in the main application layout (`app/views/layouts/application.html.erb`). You should template in the contents of your flash hash.Editing Owners
-
You already have routes for
owners#edit
andowners#update
, sinceroutes.rb
callsresources :owners
. Now, set up controller methods forowners#edit
andowners#update
, as well as a view for editing owners (edit form). -
Make sure your
owners#update
method also handles errors by redirecting if the user submits invalid data and displaying a flash message in the view. -
Common keys for flash messages are
:notice
, which just displays some information, and:error
, which means something has gone wrong. Add styling to visually distinguish between these kinds of flash messages. -
If you look at
seeds.rb
, you'll see FFaker is set up to generate seed data. In your Rails console, tryFFaker::PhoneNumber.phone_number
a few times. Just like real user data, the phone numbers don't have a standard format. Fill in thenormalize_phone_number
method so that it will:
- remove
1
from the beginning of the owner's phone number, and - remove the characters
(
,)
,-
, and.
from the owner's phone number.
The
before_save
method makes it so thenormalize_phone_number
method gets called whenever an owner is about to be saved in the database.
Part 2: Owners Have Many Pets
-
In addition to owners, this app has a model for pets. In this app, each owner will have many pets, and each pet will belong to one owner. Change the
Owner
andPet
models to reflect this relationship. -
Add a foreign key to the
Pet
table so that each pet stores a reference to its owner.
See the ActiveRecord Migrations Rails guide for how add a foreign key to a table that's already been created.
Hint: how to generate migration to add foreign key?
The example from the docs adds a user foreign key to a products table, by running `bin/rails generate migration AddUserRefToProducts user:references`, but you can also use something like `rails g migration AddUserRefToProducts user:belongs_to`. Just replace the example models with the names this app needs!- In the Terminal, open up the Rails console, and create a few associated instances of pets and owners.
irb(main):001:0> ash = Owner.create({
irb(main):001:1> first_name: "Ash",
irb(main):001:2> last_name: "Ketchum",
irb(main):001:3> email: "a_ketchum@example.com",
irb(main):001:4> phone: "(03) 1234-5678"
irb(main):001:5> })
irb(main):001:0> pikachu = Pet.create({
irb(main):001:1> name: "Pikachu",
irb(main):001:2> breed: "pokemon"
irb(main):001:3> })
irb(main):001:0> ash.pets << pikachu
Compare ash
's id
with pikachu
's new owner_id
.
Model Validation for Pets
- Practice TDD. Pets are required to have both
name
andbreed
, andname
cannot be longer than 255 characters. Using theOwner
model tests as an example, write tests for these validations.
Note that two gems are included to add extra Rails-appropriate RSpec features to this project:
rspec-rails
andshoulda-matchers
. You can see where they're set up inGemfile
andspec/rails_helper.rb
.
Hint: Where to code `Pet` model tests?
The tests for the `Pet` model belong in `spec/models/pet_spec`. This file already exists and was generated when the command `rails g model pet ...` was run.Hint: Where to look for `Owner` test examples?
The tests for the `Owner` model are in `spec/models/owner_spec`.-
Add validations to the
Pet
model. Then, test your validations withrspec spec/models/pet_spec.rb
. If you're not sure of the quality of your tests, try a few valid and invalid inputs in the console to make sure invalid inputs don't get saved. -
At this point, you can "comment in" the parts of the
db/seeds.rb
file that relate to pets and runrails db:seed
. This will destroy all old pets and create new ones.
Pet Routes
Nest routes for pets inside the routes for owners. Start with just an few routes:
# config/routes.rb
resources :owners do
resources :pets, only: :index, :show, :new, :create
end
Run rails routes
in the Terminal to see the new routes. You can see a table of nested routes and each route's purpose in the Routing Rails guide.
Pet Index and Show
-
On the owner show view, add a "view this owner's pets" link. Remember to use
link_to
. The link should go to the path that will show all of that owner's pets. Reference the route table in the Routing Rails guide. -
The pets index view will show all the pets for a particular owner. Finish filling in the pets index view template. The pets index view should list the names of all pets belonging to the owner.
Hint: What data will this view need from the controller?
Since we're looking for the pets from a single owner, the view will need to know which owner to use (`@owner`). If you have your model relationship set up correctly, an owner's pets are simply `@owner.pets`.-
Add a link to each pet's name that leads to the pet's show page. Remember to use
link_to
. -
Fill in the
pets#index
controller action so that the view has the necessary information to display. -
Fill in the pet show template to display the pet's name and breed.
-
Fill in the
pets#show
controller action to give this view the necessary information.
Pet New and Create
-
On the pet index view, add a link to the path for the new pet form. Remember to reference the route table in the Routing Rails guide.
-
Create a new pet view that renders a form. The form should have text fields for the pet's
name
andbreed
. Research the syntax forform_for
with nested resources.
Hint: research help?
The top google result for "form_for nested resource" is a StackOverflow question, and the top answer has the necessary syntax. Take a look at [the answer](http://stackoverflow.com/a/4611932).- Add a
new
action to the pets controller, and have the controller retrieve the data necessary to create a new pet for a particular owner.
Hint: what data is necessary?
Like with most `new` actions, you'll want a dummy new pet to use with the `form_for` helper. Since this pet is being added to a particular owner, you'll also need to use that owner's information.-
Add a
create
action to the pets controller. This action will need to find the proper owner, make and save a new pet, and add the pet to the owner's list of pets. It can redirect to the new pet's show page when the creation is successful. -
If there is an error in the creation of the new pet, add a flash message. Redirect back to the new pet form for that owner.
Part 3: Choose Your Own Adventure
Three types of stretch challenges lay before you. Pick and implement the set(s) you find interesting. Solutions are provided.
Circumnavigate the Site for User Experience
Practice using path helper methods by adding link_to
s to help users move among the pages of your site. Consider adding:
- a link to the owner index from the owner show page
- a link to the owner's show page from the list of their pets
- a link to the owner's list of pets from the pet show page
- a link to the site index on every page (keep it DRY!)
Follow the Routes to Full CRUD
Create or fill in routes, controllers, and views for the missing crud actions for owners and pets. Choose one route at a time. It might be easiest to start with destroy
; just remember the difference between destroy
and delete
!
Play with Pets!
Practice your Ruby skills - get more time with the Date
and DateTime
built-in classes.
-
Generate and run a migration to add a
date_of_birth
field to thePet
model. The type of this field should bedate
. Display the pet'sdate_of_birth
in the view forpets#show
. -
Fill in the
Pet
model'sdate_of_birth_cannot_be_in_the_future
method. This method should add an error to the validation errors if the pet'sdate_of_birth
is in the future. See the Validations Rails guide. -
Fill in the
Pet
model'sage
instance method. If the pet instance has adate_of_birth
, this method should calculate and return the pet's age in years (as a decimal). If the pet doesn't have adate_of_birth
, theage
method should returnnil
. Display the pet'sage
in the view forpets#show
.