JSON Schema

[anonimusprogramus]

Hi Sebastian.

I like v8n, simple and light. I'm trying to use v8n with Fastify framework upon request validation.

How to make v8n outputs a JSON Schema compatible object?

As explained here, but I'd like to use v8n instead of Joi.

Thanks a lot.

[imbrn]

Hello @anonimusprogramus, thanks for your question.

I don't know the Fastify framework very well, so maybe this solution is not gonna work as you expect. But as I was looking at the documentation, I ended up with something like this:

function validate(schema, value) {
  const [error] = schema.testAll(value);
  return error ? { error } : { value };
}

fastify.post('/the/url', {
  schema: v8n().schema({
    body: v8n().schema({
      hello: v8n().string()
    })
  }),
  schemaCompiler: schema => data => validate(schema, data)
}, handler)

The validate function is a kind of adapter to the Fastify expected interface. I did it very simple in this example (with destructuring syntax), but you can use your imagination to create custom messages by using the v8n ValidationError returned by testAll. 🙂

[anonimusprogramus]

Bruno, thanks for your reply, much apreciated.

I've been trying your suggestion and some varians but still no luck, perhaps I need to read again v8n, fastify and json schema again. Hope there's something I missed. And this issue won't stop me from using v8n, it's awesome!

Again, thank you very much.