Schema.json_schema() does not return properties for a dict of dicts where first level key can be any string

[WillGibson]

We want to auto generate a reference from our schema and have been playing with the following which looks promising in conjunction with Schema.json_schema() and then us parsing the JSON into a more friendly display format...

Schema( {
    Literal("application", description="The name of your application. Letters, numbers, hyphens and underscores are allowed."): str
})

Our schema include several dicts of dicts where the first level key can be any string. E.g...

Schema( {
    "dict-of-dicts-any-name-allowed": {
        str: {
            "property-1": str
        }
    }
})

There seems to be an issue with Schema.json_schema() where, for these, it does not return any properties. E.g...

{
  "type": "object",
  "properties": {
    "dict-of-dicts-any-name-allowed": {
      "type": "object",
      "properties": {},
      "required": [],
      "additionalProperties": true

    }
  },
  ...
}

I have created a gist so that you can see this easily first hand.

Is there something we should be doing to get Schema.json_schema() to return the properties for these dicts?

If this is not currently supported, would you be open to us submitting a pull request to add support for it?

If we are submitting a pull request, would the following approach be suitable for the expected output (based on the example above)?

{
  "type": "object",
  "properties": {
    "dict-of-dicts-any-name-allowed": {
      "type": "object",
      "properties": {
        "<string_key>": {
          "type": "object",
          "properties": {
            "property-1": {
              "type": "string"
            }
          },
          "required": [
            "property-1"
          ],
          "additionalProperties": false
        }
      },
      "required": [],
      "additionalProperties": false
    }
  },
  ...
}

[jeliebig]

Based on the Schema you provided the correct JSON schema would look like this:

{
    "type": "object",
    "properties": {
        "dict-of-dicts-any-name-allowed": {
            "type": "object",
            "properties": {},
            "required": [],
            "additionalProperties": {
                "type": "object",
                "properties": {
                    "property-1": {
                        "type": "string"
                    }
                },
                "required": ["property-1"],
                "additionalProperties": false
            }
        }
    },
    "required": ["dict-of-dicts-any-name-allowed"],
    "additionalProperties": false,
    "$id": "example-id",
    "$schema": "http://json-schema.org/draft-07/schema#"
}

You can find more examples in the tests of my PR which adds support for these kind of schemas: #340

[WillGibson]

Thanks for this @jeliebig.

I am not longer working on the project where this came up so will tag @JohnStainsby and @a-gleeson who I think might still have an interest in this.