Programming Language independent Model Validation

Question

Let's say you use several different programming languages and frameworks in your infrastructure to handle large amounts of traffic etc.

Example Stack:

1. event driven API servers (using Scala, node.js, Ruby EM)
2. a standard full stack webapp (e.g. Rails)
3. (maybe more technologies)

When using different languages and frameworks I usually end up duplicating most of the model validations because every "customer entry point" needs to validate its input. This is of course a pain to keep in sync.

How would you handle this without something like CORBA?

Answer 1

Your best bet would be a framework that allows you to specify model validation in a language agnostic format, like JSON. You might end up with a validation schema of sorts, say:

{
  "name": [
    {
      "validate": "length",
      "minLength": 6,
      "maxLength": 10
    },
    ...
  ],
  ...
}

You would then have language-specific validators that could parse this format. The validators only need to be written once, and then you maintain a single schema for each model.

However, this is probably sounding a lot like CORBA/SOAP/Thrift/ProtocolBuffers/etc. at this point. That's because they were written to solve these types of problems, and you'll end up reinventing a few wheels if you write it yourself.