Frontier Tutorials / Writing an ObjectNotFoundHandler / ONFH Applications

ONFH Applications

The ObjectNotFoundHandler is a very powerful mechanism. You could, for example, use an ONFH to serve an entire website. Some other possible uses:

• Serve Cascading Style Sheets (see Bonus: Mode 3 Utility Script).

• Serve Javascript "files" (see Bonus: Mode 3 Utility Script).

• Provide url-based access to a database. For example, http://yoursite.com/members/member_id/ might return (the contents of) a page with information about a member of your organization, and the presence of post-args might indicate a request for an update of that information.

• Serve up Fronter scripts on demand (encoded as Fat Pages).

With Power Comes Responsibility

Be careful what you serve up using ONFHs, though. They allow you to serve up literally anything that is accessible from within Frontier. This includes a lot of stuff that should remain private (or at least, should not be published arbitrarily):

• Frontier built-ins. These belong to UserLand; only UserLand has the authority to decide whether, when, and how to publish them.
• User settings. Especially passwords and serial numbers!
• Other People's Code. As with UserLand's stuff, don't publish without permission.
• Did I say passwords and serial numbers?

If you do decide to serve up arbitrary Frontier content (text, scripts, etc.), I suggest you carefully restrict what can be served up to a specific table or tables created solely for that purpose.