When overriding theme functions in Drupal 7 you would normally copy the theme function into the template.php and alter it to suit your needs. This isn't always convenient though, especially if you are trying to abstract functionality into modules and not have code in your theme layer that is reliant on module code. If you add theme override functions to your module files then they won't do anything as Drupal isn't looking for them there and won't pick them up.
Or, how you can render a Drupal page with an entirely different template.
I recently had a requirement where I needed to get Drupal to render a single page of HTML that was entirely separate from the normal page layout of a site. This was actually part of an API callback, but this got me involved in looking at how delivery callbacks work in Drupal 7. It isn't necessary to create a new theme just for the job of rendering a single page with some custom HTML, especially as Drupal has mechanisms to provide this built in.
The city of Sunderland played host to DrupalCamp North, which saw Drupal users and contributors travelling from all over the UK and Europe to attend. The event, which was held from 24th-26th July, was jointly led by the North East, North West and Yorkshire Drupal User Groups and consisted of a three day sprint, a business day, and a two day conference.
There are a few ways in which you can create complex node access systems. Modules like Taxonomy Access Control and Node Access will allow you to restrict node access in different ways, and work very well for setting up taxonomy or role based access control. There are a few edge cases where you need to restrict access to a node based on some arbitrary conditions like the age of the user or the contents of a field. This is where the build in Drupal access control mechanisms come into play.
Basic HTTP authentication is a simple authentication mechanism that is used to prevent access to an site or directory on a server. It is by no means the most secure authentication mechanism but it is commonly used on staging sites in order to prevent unwanted access. This is a good way of preventing search engine bots from spidering the staging site, which is undesirable as it can cause staging site pages appearing in search engines results.
When generating markup in Drupal you'll often want to store the output in a cache instead of regenerating it every time. This is especially important for potentially expensive rendering tasks that don't change between page requests. Drupal 7 comes with a cache system that can be taken advantage of with the cache_get() and cache_set() functions. There is also a third function called drupal_static() that also fills in gaps between these two functions.