Rails%203%20In%20Action

68 CHAPTER 3 Developing a real Rails application
}
},
"controller" => "projects"
TIP If you’d like to inspect the params hash at any point in time, you can
put p params in any action and then run the action either by accessing it
through rails server or by running a scenario that will run an action
containing this line. This outputs to the console the params hash and is
equivalent to doing puts params.inspect.
All the hashes nested inside this hash are also HashWithIndifferentAccess hashes. If
you want to get the name key from the project hash here, you can use either { :name =>
"TextMate 2" }[:name], as in a normal Hash object, or { :name => "TextMate 2"
}['name']; you may use either the String or the Symbol version—it doesn’t matter.
The first key in the params hash, commit, comes from the Submit button, which
has the value Create Project. This is accessible as params[:commit]. The second key,
action, is one of two parameters always available, the other being controller. These
represent exactly what their names imply: the controller and action of the request,
accessible as params[:controller] and params[:action] respectively. The final key,
project, is, as mentioned before, a HashWithIndifferentAccess. It contains the
fields from your form and is accessible via params[:project]. To access the name field,
use params[:project][:name], which calls the [] method on params to get the value
of the :project key and then, on the result, calls [] again, this time with the :name
key to get the name of the project passed in.
When new receives this HashWithIndifferentAccess, it generates a new Project
object with the attributes based on the parameters passed in. The Project object will
have a name attribute set to the value from params[:project][:name].
You call @project.save to save your new Project object into the projects table.
The flash method in your create action is a way of passing messages to the next
request, and it’s also a HashWithIndifferentAccess. These messages are stored in the
session and are cleared at the completion of the next request. Here you set the
:notice key to be Project has been created. to inform the user what has happened. This
message is displayed later, as is required by the final step in your feature.
The redirect_to method takes either an object, as in the create action, or a path
to redirect to as a string. If an object is given, Rails inspects that object to determine
what route it should go to, in this case, project_path(@project) because the object
has now been saved to the database. This method generates the path of something
such as /projects/:id, where :id is the record id attribute assigned by your database
system. The redirect_to method tells the browser to begin making a new request to
that path and sends back an empty response body; the HTTP status code will be a 302
Redirected to /projects/1, which is the currently nonexistent show action.
Upon running rake cucumber:ok again, you are told that your app doesn’t know
about a show action:
And I press "Create Project"
The action 'show' could not be found for ProjectsController