Ruby on Rails is a so-called opinionated framework, this means that it bakes in a bunch of conventions for how applications should be built. By following these conventions, you can write less code, and make more software. This is great, unless some of those conventions depend on something inconsistent or irregular.

One thing that is particularly inconsistent and irregular is the English language. Do you remember the rule for Is and Es? “I before E except after C and except after words like neighbor and weigh…”. This is typical of the English language, exceptions abound. There is no consistent rule we can give for combining the letters I and E in a sentence.

Similarly, pluralization follows no single scheme, there are words like ‘chair’ that are pluralized as ‘chairs’, and then there are words like ‘sheep’ that are their own plurals. Finally, there are words inherited from Latin like cactus, which can be pluralized as ‘cactii’ or ‘cactuses’.

The reason I am bringing this up is that Ruby on Rails has a module called ActiveSupport::Inflector that has pluralization methods built into it. One of the conventions used in rails applications is the following: if you have a data model representing a thing, then rails generates a table in your database called things, where each record in the database represents a single thing.

The inflector module kicks in so that you don’t have to say what the name of the table will be, rails takes care of that for you. This works fine, most of the time. I recently had to fix an application that was failing because it has ambiguous routes, that means that a route has multiple possible controller actions it could trigger, this is not good, hence the error. The culprit was a model called series. When you pluralize it:

The result is the same word, this leads to ambiguous routes, since there is a series_path (singular) and series_path (plural) that are supposed to mean different things.

This problem took me a few days to solve, and it would have been a non-issue if I would just made my own database table names and route. Not because my conventions are better, but simply because I would have been forced to think about what things are called, instead of trusting that the conventions of the framework will yield consistent results.

I think that ‘convention over configuration’ is a good idea, but only when the conventions are logical and make sense. At the vary least, there should be no ambiguities.