Rails%203%20In%20Action

5.1.3 Defining a has_many association
Creating tickets
The tickets method is defined by an association method in the Project class called
has_many, which you can use as follows, putting it directly above the validation you put
there earlier:
has_many :tickets
As mentioned before, this defines the tickets method you need but also gives you a
whole slew of other useful methods, such as the build method, which you call on the
association. The build method is equivalent to new for the Ticket class (which you
create in a moment) but associates the new object instantly with the @project object
by setting a foreign key called project_id automatically. Upon running the feature,
you get this:
And I follow "New Ticket"
uninitialized constant Project::Ticket (NameError)
You can determine from this output that the method is looking for the Ticket class,
but why? The tickets method on Project objects is defined by the has_many call in
the Project model. This method assumes that when you want to get the tickets, you
actually want objects of the Ticket model. This model is currently missing; hence, the
error. You can add this model now with the following command:
rails generate model ticket title:string description:text project:references
The project:references part defines an integer column for the tickets table called
project_id in the migration. This column represents the project this ticket links to
and is called a foreign key. You should now run the migration by using rake
db:migrate and load the new schema into your test database by running rake
db:test:prepare.
The rake db:migrate task runs the migrations and then dumps the structure of
the database to a file called db/schema.rb. This structure allows you to restore your
database using the rake db:schema:load task if you wish, which is better than running
all the migrations on a large project again! The rake db:test:prepare task
loads this schema into the test database, making the fields that were just made available
on the development database by running the migration also now available on
the test database.
Now when you run bin/cucumber features/creating_tickets.feature, you’re
told the new template is missing:
And I follow "New Ticket"
Missing template tickets/new, application/new
with {:handlers=>[:erb, :builder],
:formats=>[:html],
:locale=>[:en, :en]}.
Searched in:
* ".../ticketee/app/views"
A file seems to be missing! You must create this file in order to continue.
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