How best to generate OpenAPI schema with reusable enums? #1303
Description
First check
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Description
How can I generate an OpenAPI schema with reusable enum classes?
If I have 2 pydantic models that reference the same enum class. By default, the generated OpenAPI schema will look something like this:
{
"components": {
"schemas": {
"Foo": {
"title": "Foo",
"type": "object",
"properties": {
"some_enum": {
"title": "Some Enum",
"enum": ["VALUE_ONE", "VALUE_TWO"],
"type": "string"
}
}
},
"Bar": {
"title": "Bar",
"type": "object",
"properties": {
"some_enum": {
"title": "Some Enum",
"enum": ["VALUE_ONE", "VALUE_TWO"],
"type": "string"
}
}
}
}
}
}I'm looking for a way to generate something like this instead:
{
"components": {
"schemas": {
"Foo": {
"title": "Foo",
"type": "object",
"properties": {
"some_enum": {
"$ref": "#/components/schemas/SomeEnum"
}
}
},
"Bar": {
"title": "Bar",
"type": "object",
"properties": {
"some_enum": {
"$ref": "#/components/schemas/SomeEnum"
}
}
},
"SomeEnum": {
"type": "string",
"enum": ["VALUE_ONE", "VALUE_TWO"]
}
}
}
}The main use case for this feature is to facilitate client code generation — the first schema will produce 2 separate enum classes in the client code, whereas the second schema will generate a single enum class that's referenced in both the Foo and Bar models. This follows the "Reusable enums" pattern here:
https://swagger.io/docs/specification/data-models/enums/
I recognize that this is related to pydantic as well as fastapi, but given that fastapi has its own OpenAPI layer on top of pydantic, I was hoping to find a solution here.
Is there a recommended way to achieve this behavior?