Allowing the use of a modified Ajv instance about fast-json-stringify HOT 6 CLOSED

Thanks for reporting! Would you mind to share an example of what it is not working for you?

from fast-json-stringify.

Sure! Here's an exmaple:

const ajv = require("ajv")();
const server = require("fastify")();

ajv.setFormat("test", /[a-z]{24}/);

server.setSchemaCompiler(schema => ajv.compile(schema));

server.post("/", {
  schema: {
    response: {
      "200": {
        type: "object";
        properties: {
          test: {
            type: "string",
            format: "test"
          }
        }
      }
    }
  }
}, async (req, res) => ({}));

server.listen();

Results in an error similar to:

I realise that it would have made more sense to open this on the main Fastify repository first, apologies! But as I was reading the code for Fastify I (think) I tracked it down to the fact that it uses this package to compile the response schemas.

from fast-json-stringify.

The problem is that this module is not used to validate the responses before sending them. It is used to render them. As such, it does not know anything about your format, it would in fact be totally ignored even if you pass it through. We use AJV to validate that your schema is valid JSON schema.

Passing in a custom AJV would remove the error, but it will just make that ignored.

from fast-json-stringify.

That makes sense, and I don't want any validation, I'd just like to be able to use a schema that I use in both the request and response (because they share the same data) but have the custom format ignored when it is used in the response.

I've realised that there is an alternative to passing in a custom Ajv instance but instead use the option unknownFormats: "ignore" on the internal Ajv instance of this package, which would allow custom formats in the response schema but ignore them.

from fast-json-stringify.

I've realised that there is an alternative to passing in a custom Ajv instance but instead use the option unknownFormats: "ignore" instead which would allow custom formats in the response schema but ignore them.

I think we should add this to fast-json-stringify ajv config.

from fast-json-stringify.

Yes that's what I was thinking. 👍

I'll open a PR. Thanks for the quick responses. 😄

from fast-json-stringify.