On one page, I want a form. This form has a single field for a ticket
number. When someone enters a ticket number and submits the form, they
are shown a second page with links to download files. And here is a
list of other criteria:
- validate ticket numbers (is a number within a certain range)
- "used" tickets are stored in the database
- if a ticket is not in the database, add it
- if a ticket is in the database, increase "count" field by one
This seems simple enough, but I don't quite understand how to take all
of rails discrete processes (create using POST, update using PUT, show
using GET, all in separate actions within a controller) and roll it
all up into a single controller (or put it in the model, which makes
sense).
Should I scrap trying to use ActiveRecord and go to straight Ruby for
this? I've never done database access straight from Ruby before.
I don't think this is too simple to use for Rails. You may want to
consider using Sinatra or a smaller web framework, but I wouldn't
write it in straight Ruby unless you want that experience.
As for how to do this in Rails, usually when you have a form it should
map to the "new" or "edit" controller actions. Here you are creating
tickets. The only exception is that if the ticket already exists in
the database you want to update the existing record. However, this
behavior still belongs in the create action because, from the
interface perspective, the user is still creating a ticket.
Whenever you're deciding whether a request should be POST (create) or
PUT (update), ask yourself this: if the user submits the same request
again, will the second request alter the database? When updating a
record you can submit the PUT request as many times as you like
without effecting the database much. In contrast if you submit a POST
request multiple times it will create multiple records. Here you're
incrementing a counter so the database changes each time the request
is submitted, therefore a POST (create) request is the right way to
go.
The create action might look like this.
def create
@ticket =
Ticket.find_or_initialize_by_number(params[:ticket_number])
@ticket.increment(:count) unless @ticket.new_record?
if @ticket.save
redirect_to @ticket
else
render :new
end
end
Everything else would be standard RESTful controller actions.
Actually, I believe this is even simpler than you think.
Why don't you have a process which is:
People enter the ticket number
After validation they are directed to the download page.
You don't need to check if the ticket is in the database, you add it anyway.
Later, you'll be able to list the tickets entered and to count them.
if you use the scaffold, you have the new page that takes care of entering the ticket
This should use the create action in which you put the validation code and make sure that it redirects to the download page
The index page can be tuned to display the list of tickets and their respective count