jsonschema.exceptions._RefResolutionError: hypothesis-jsonschema does not fetch remote references

[nbro10]

My understanding is that we can refer to other local JSON schemas using $ref. So, I have these 2 schemas in my local file system (in the same directory)

main.json

{
    "type": "object",
    "properties": {
        "language": {
            "$ref": "./language.json#"
        },
        "required": [
            "language",
        ],
        "additionalProperties": false
    }
}

And language.json

{
    "type": "string",
    "enum": [
        "en",
        "fr"
    ]
}

Now, I was trying to generate a random sample by calling from_schema(my_schema).example(), but I keep getting the error

jsonschema.exceptions._RefResolutionError: hypothesis-jsonschema does not fetch remote references (uri='./language.json')

and I'm not sure why.

Instead of "./language.json#", I also tried "language.json#" and other variations I've seen on the web...

Does this library support this? If yes, how? If not, what alternative do you suggest?

[Zac-HD]

A "remote reference" is anything outside the current document, so unfortunately this is working as intended - local filesystem and remote URL both involve IO, and that's the problematic part.

[nbro10]

@Zac-HD Why is it problematic to read from the file system? Can you clarify?

[Zac-HD]

IO and state make managing the logic much more difficult, introduce performance issues, and make caching unsafe. I'd suggest resolving the schema into a single document before handing that to hypothesis-jsonschema.

[nbro10]

Ok, but you'd not be forced to use it. If you want performance, you can just create a single schema, if you want composability, you'd need $ref. It looks like a big limitation to me and I'd assume that I am not the first one asking or looking for this feature.

[roversch]

Hey I totally understand where you're coming from @Zac-HD , but can you add a note somewhere? I just lost 2 hours before I stumbled upon this issue.

As of version 0.11, this includes resolving non-recursive references!

This signals that $ref into other file is supported.

Anyway, thanks for the great library!