Build Formatter Middleware

[mbleigh]

The Formatter takes care of handling the various formats into which Grape API responses can be converted. It consists of two parts:

1. Determining from the request what kind of format is desired.

This would first look at any format appended as an extension (i.e. .json or .xml). If no format is appended, it would properly parse and use the HTTP Accept header (including weighted quality values) to determine an array of acceptable formats.

2. Converting data to the desired format.

The middleware would be transparent in Grape, but also usable outside of it. Any data set in the Rack env hash on the key api.response_data should automatically be converted to the desired format (falling back to a to_format call if existing methods aren't in place) and sent along as the response body. A proper content type should also be set based on the used response format.

This should be flexible enough to allow for stranger formats (for example, a PDF or a Zip file response).