Rails%203%20In%20Action

220 CHAPTER 9 File uploading
This file tells Git which files you don’t want versioned. The whole file should look like
this now:
.bundle
db/*.sqlite3
log/*.log
tmp/**/*
public/system
By default, the .bundle directory (for Bundler’s configuration), the SQLite3 databases,
the logs for the application, and any files in tmp are ignored. With public/system
added, this directory is now ignored by Git too. You should also remove this
directory from your latest commit, and thankfully, Git provides a way to do so by using
these two commands:
git rm public/system/assets/1/original/speed.txt
git commit --amend -m "Added the ability to attach a file to a ticket"
The first command removes the file from the filesystem and tells Git to remove it from
the repository. The second command amends your latest commit to exclude this file,
and it will be as if your first commit with this message never existed. Let’s push this
change:
git push
Great! Now you can attach a file to a ticket. There’s still some work to do, however.
What would happen if somebody wanted to add more than one file to a ticket? Let’s
take a look at how to do that.
9.2 Attaching many files
You have an interface for attaching a single file to a ticket but no way for a user to
attach more than one. Let’s imagine your pretend client asked you to boost the number
of file-input fields on this page to three.
If you’re going to add these three file-input fields to your view, you need some
more fields in your database to handle them. You could define four fields for each fileupload
field, but a much better way to handle this is to add another model.
Creating another model gives you the advantage of being able to scale it to not just
three file-input fields but more if you ever need them. Call this model Asset, after the
name you gave to the has_attached_file in the Ticket model.
When you’re done with this feature, you should see three fileupload
fields as shown in figure 9.1.
You can create new instances of this model through the ticket
form by using nested attributes. Nested attributes have been a feature
of Rails since version 2.3, and they allow the attributes of an associ-
ation to be passed from the creation or update of a particular
resource. In this case, you’ll be passing nested attributes for new
Figure 9.1
File-upload boxes