Doing things in models on save/update

Erik — Mon, 19 Jun 2006 13:31:14 +0000

So, I wanted to do some sweet gsubbing before the save of projects in Rails. I found the API docs had a wealth of information about this, but I figured I’d post my method anyway:


  before_create :fix_amount
  before_update :fix_amount

Now you just define them under private in the model:


  def fix_amount
    self.amount.gsub!(/^\$/, "")
  end

This takes those pesky $’s right out, back to the back yard where they belong.

HTTP URL Validation Improved

Erik — Fri, 16 Jun 2006 16:40:28 +0000

I found the HTTP URL Validator for Rails very interesting, and well coded, yet it lacked some things such as URL format restrictions. I added some things, and I came up with a sweet solution.
It checks the format of the given URL, the content type, and whether it was permanently moved. I might be adding to this in the future.


#Check for content type:
  validates_http_url :url, :content_type => "text/html"

#Do not check for content type, just make sure the site is accessible:
  validates_http_url :website

#Make sure there is a DNS entry for a domain
  validates_http_domain :domain
# Domain must be in 'www.site.com' for or 'site.com' form.
# No http://, no path.

Update (6/26/06)

Added the validates_http_domain method:


def validates_http_domain(*attr_names)
  validates_each(attr_names) do |record, attr_name, value|
    # Set valid true on successful connect (all we need is one, one is all we need)
    failed = true
    possibilities = [value, "www."+value]
    possibilities.each do |url|
      begin
        temp = Socket.gethostbyname(url)
        rescue SocketError
          next
        end
        failed = false
        break
    end
    record.errors.add(attr_name, "cannot be resolved.") if failed
  end
end

Now I can just use


:validates_http_domain :website

in my controller, and everything comes up roses. ;)

Update (9/30/06)

It was brought to my attention through a dialogue of emails and the comments that I needed a simple way for people to modify the plugin to accept different codes depending on their needs, or at least a simple way for me to modify the default accepted codes. Therefore, I made an array in the library called allowed_codes:


           allowed_codes = [
            Net::HTTPMovedPermanently,
            Net::HTTPOK,
            Net::HTTPCreated,
            Net::HTTPAccepted,
            Net::HTTPNonAuthoritativeInformation,
            Net::HTTPPartialContent,
            Net::HTTPFound,
            Net::HTTPTemporaryRedirect,
            Net::HTTPSeeOther
           ]

I’ll make it so you can push on your own custom codes from the model soon. This is what I envision:


  validates_http_url :website, :extra_codes => [ HTTPResetContent, HTTPPartialContent ]

I’ll post here when this is reality, and probably make another blog post as well so the aggregators get it.

You can download it with svn:


svn co https://modzer0.cs.uaf.edu/repos/hank/code/http_url_validation_improved

Or use it as a plugin:


./script/plugin install -x https://modzer0.cs.uaf.edu/repos/hank/code/http_url_validation_improved

The above command only works if you have your entire rails project in subversion. If you do not, which I don’t recommend, you should either add it to a repository or alternatively remove the *-x* from the command. Of course, this will remove support for updating to the new code if I make a change.

Schadenfreude » validation

Doing things in models on save/update

HTTP URL Validation Improved

Update (6/26/06)

Update (9/30/06)