Tip: When is it best to use a configuration file?
Given that there are multiple ways to collect configuration data, when is it best to use a configuration file instead of via a user interface? This is actually a very difficult question to answer definitively. Consider the following:
Will the configuration property need to be modified frequently? If so, you may consider implementing a UI for sheer convenience.
Will setting the configuration property need to be a highly privileged right on the system? If so, then by placing it is a config file you ensure that only users with direct access to the file system will have permission to edit it.
How quickly do I need to introduce a new feature I am planning that requires configuration? If the answer is soon, then there is no quicker way to provide configurable features then via a config directive.
Will my feature need to be configured on a blog-by-blog basis? If so, then a config directive is not likely to be an ideal solution.