Comments on: Quick and Dirty URL Validation

By: Bob Aman

Bob Aman — Wed, 11 Feb 2009 21:06:49 +0000

If I wanted to break this, I think I'd write a custom "webserver" that responded to a HEAD request with an unending stream of headers. Server never closes the connection, just keeps sending you headers until the client finally gives up, assuming it ever does.

By: Trevor

Trevor — Wed, 11 Feb 2009 17:22:31 +0000

Hmm… yes… I think I got it now? I pasted it from running code, so I hope so

By: name

name — Wed, 11 Feb 2009 16:49:39 +0000

There is still one slash left unescaped.

By: Trevor

Trevor — Wed, 11 Feb 2009 15:58:54 +0000

This is my favorite URL format validator right now: http://github.com/henrik/validates_url_format_of/... URI.regexp didn't catch a lot of invalid stuff I tried to trow at it.

By: Trevor

Trevor — Wed, 11 Feb 2009 10:52:05 +0000

Ah yes. Fixed, thanks!

By: name

name — Wed, 11 Feb 2009 02:11:58 +0000

Btw, regexp is wrong. You should escape slashes:
regexp = url.match(/https?://([^/]+)(.*)/)

By: Trevor

Trevor — Tue, 10 Feb 2009 21:13:47 +0000

Thanks, Walter. That looks like a good plugin to consider if you're worried about overkill but need more than quick and dirty.

By: Walter McGinnis

Walter McGinnis — Tue, 10 Feb 2009 16:51:58 +0000

Sorry, meant to add link to the source. It can be found here: https://modzer0.cs.uaf.edu/repos/hank/code/http_u...

By: Walter McGinnis

Walter McGinnis — Tue, 10 Feb 2009 16:51:16 +0000

This is the same basic concept of the older http_url_validation_improved plugin. It's not on github, so perhaps that is why you missed it.

We use it in Kete (http://kete.net.nz) to achieve what you are after. It does look like it could use that URI.regexp refactoring added to it.

One nice thing is that it will check for allowed content types with configuration. It also gives more finegrained feedback when validation fails.

By: Trevor

Trevor — Tue, 10 Feb 2009 15:53:35 +0000

As an aside, found this easy way to do basic URL format validation:

http://www.ruby-doc.org/core/classes/URI.html#M00…

require 'uri'

validates_format_of :uri, :with => URI.regexp

Very nice – no need for a custom regexp