There is a world where developers need never worry about poorly formatted JSON. This is not that world. If a client submits invalid / poorly formatted JSON to a Rails 3.2 or 4 app, a cryptic and unhelpful error is thrown and they’re left wondering why the request tanked. Example errors The error thrown by the parameter parsing middleware behaves differently depending on your version of Rails: 3.2
![Catching Invalid JSON Parse Errors with Rack Middleware](https://cdn-ak-scissors.b.st-hatena.com/image/square/beac31a4be8e4962e2fefc94fd70b667eb3e9cec/height=288;version=1;width=512/https%3A%2F%2Fimages.thoughtbot.com%2Fblog-images%2Fsocial-share-default.png)