Question: Circular References in the scheme

[florintene]

Hi,

I do have a question, as I couldn't find in the docs, if circular references are supported by the asyncapi-validator ?
Currently, for a definition that has circular references the validation fails with:

/node_modules/json-schema-traverse/index.js:67
function _traverse(opts, pre, post, schema, jsonPtr, rootSchema, parentJsonPtr, parentKeyword, parentSchema, keyIndex) {
                  ^

RangeError: Maximum call stack size exceeded
    at _traverse (/node_modules/json-schema-traverse/index.js:67:19)

Thank you,

[WaleedAshraf]

I haven't tested it, but I think it should work. Though it's possible that there is some bug.
Feel free to open a PR if you spot the issue, I'll try to look into this in the next few days.

[WaleedAshraf]

@florintene It seems that circular refs are not supported, as per AJV here: https://ajv.js.org/security.html#circular-references-in-javascript-objects. I'll update the readme.

[florintene]

Thank you very much @WaleedAshraf.

Circular references are always a problem but i'm surprise that AJV doesn't support them.
I had a look through the AsyncAPI-Parser and they do support (mark & flag) the circular references.

There are options out there that can help in a combination with AJV.
For example, json-schema-ref-parser and json-schema-ref-parser(Github)

Used the bundle:

Bundles all referenced files/URLs into a single schema that only has internal $ref pointers.
...
This also eliminates the risk of circular references, so the schema can be safely serialized using JSON.stringify().

and then AJV can compile successfully the schema.

Not to mention that there is always the option to review the schema and drop the circular references - although that is not always possible.

Anyway, hope the above info might help others.

Thank you ;)

[WaleedAshraf]

I see your point. I think it's possible the way you suggested, though I'd prefer if it's done within asyncapi/parser-js as it handles the parsing. An optional parameter can be passed to remove circular references. It's already using json-schema-ref-parser. I suggest opening an issue there.

Another way you can try is to parse the schema with asyncapi/parser-js then remove the circular refs using json-schema-ref-parser and then use asyncpi-validator. This may work, but I haven't tested it yet.

[florintene]

Yes, is something to explore.
I'll have a look over the week to see if I manage to make it play nicely together :)
I think one of the issue might be that asyncapi/parser-js is deferencing the schema so we might have to use a json stringify that can deal with circular references.

Anyway, i'll try to have a look and let you know.