Is there a way to declare "allowed values" for a property?

[mstenta]

Let's say we have a JSON object like this:

{
  "id": 1,
  "name": "My object",
  "type": "foo",
}

And the "allowed values" of the type property are either foo or bar. Is there any way to describe this with JSON Schema?

[gbathree]

Looking here: https://json-schema.org/understanding-json-schema/reference/object.html#pattern-properties

Let's take this as an example. Here, it appears by using enum we are specifying the allowed values...

{
  "type": "object",
  "properties": {
    "number": { "type": "number" },
    "street_name": { "type": "string" },
    "street_type": { "enum": ["Street", "Avenue", "Boulevard"] }
  },
  "additionalProperties": false
}

Now, one could image in *Plant Data Service land the allowed values could get quite long and complex. Perhaps what you want is to a way to specify "enum":["a", "b", "c"] where a/b/c is a reference to a big object. Then you could run a program to 'compile' the actual things together... or perhaps (better yet) we can use a HTML reference in enum so it's web-based and version controlled... I'd like to brainstorm this with @sudokita also...