Convention Over Configuration Pattern

The final version of the pattern that I wrote for this class is now available. The html version can be found here and the pdf version can be found here.

The intent of the pattern:

Design a framework so that it enforces standard naming conventions for mapping classes to resources or events. A programmer only needs to write the mapping configurations when the naming convention fails.

I admit that the name is not coined by me. Instead it has beeb used actively in the Rails community.

As I mentioned during the writer's workshop session for this pattern, I was more interested in trying to give a definition to the phrase Convention Over Configuration. The term has been used loosely by various developers and I hope my description will offer developers a better understanding of the underlying concepts and the consequences for using Convention over Configuration.

One form of convention that I have seen - but not mentioned in the paper because it might make things too complicated - is the fact that code and resource organization can also be a form convention. For instance Rails expects to find all the ActiveRecord classes under the app/models folder. By having a convention for placing code and other resources, Rails does not need to traverse all the directories when it needs to find those files. Also, it does not need a configuration to tell it where to look for those files.

This is my first attempt at a pattern and it has been an interesting experience. It is very tempting to assume that the reader knows too much or too little. In the former case, I would make the mistake of writing too little and use too many terms. In the latter case, I tend to write too much and the underlying meaning to the pattern might be lost. In this final version, I feel that I have struck a balance between the two and have included sufficient references in case the reader wants to find out more.

The most important part of writing the pattern is actually getting feedback from other people. I was privileged to have the opinions of four members of the class and that really helped me identify the parts of the writing that need to be clarified.

Hopefully somebody finds this pattern and its description useful.

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