Ruby Schema Validation Project
An attempt to create a more universal schema format that can be used in Ruby projects to validate any incoming data, as long as it is a RUby object. At the time of writing this the two data containers being focused on are YAML and JSON.
Aside from the fact it's polite? Seriously though, I have yet to see a clean, simple, and straight-forward schema format that can be used against a variety of different data containers. I was also having trouble finding a recent and active YAML schema validation tool, specifically one written in Ruby. So here is my attempt at one!
The awesome part about RSVP is that you can write the schema in any data
container that can be parsed into a Ruby Hash or Array. I'll use YAML for my
examples, but only because I believe it has a clean and easy-to-read format. You
could use JSON, or even raw Ruby constructs; as long as it converts into a Ruby
object it can be considered a candidate for being the representation of a
desired schema.
Once you have your schema object constructed, you simply pass in a target Ruby
object for validation against the schema. The result of the validation is an
object with two key components: valid? and errors. The former returns true
if the object was considered valid or false if it wasn't. The latter is only
used in the case of invalid results, and contains an array of errors.
schema = Rsvp::Generator.from_yaml("schema.yaml")
result = schema.validate(target)
if result.valid?
# `target` object is valid according to schema.yaml
else
# did not successfully validate; inspect `result.errors` for details
end
The above example created a schema object from a YAML source file, then passed
in an arbitrary object target to be validated. Then we can use an if/else
block testing result.valid?, which is true if the object was valid and
false otherwise. Simple. The best part is that as long as the schema object is
created properly, you can use any source format to define a schema and validate
a Ruby object!
As of writing this, RSVP is targeted for use by another project of mine, Ruby View Abstractor. That means I will be developing, at first, with the needs of the Ruby View Abstractor in mind. However, I hope the community likes this concept and decides to help me grow and maintain the project. And since I am using it for my Ruby View Abstractor project, any interested in seeing how RSVP may be used in a real-life development effort can check out the abstractor.