OpenAPI generation failed with internal enums and with pydantic >=1.6.*

[arxell]

First check

• I added a very descriptive title to this issue.
• I used the GitHub search to find a similar issue and didn't find it.

Example

from fastapi import FastAPI
from pydantic import BaseModel
from enum import Enum

app = FastAPI()


class EnumExample(Enum):
    a = 1


class Foo(BaseModel):
    class EnumExample(Enum):
        a = EnumExample.a
        b = 2

    x: EnumExample


class Bar(BaseModel):
    class EnumExample(Enum):
        a = EnumExample.a
        b = 2

    x: EnumExample


class TestResp(BaseModel):
    foo: Foo
    bar: Bar


@app.get("/", response_model=TestResp)
async def test():
    return TestResp(foo=Foo(x=Foo.EnumExample.a), bar=Bar(x=Bar.EnumExample.b))

Description

• Open the browser and call the endpoint http://127.0.0.1:8000/docs.
• It returns an error Internal Server Error /openapi.json .
• The problem is relevant only with pydantic>=1.6.* versions

StackTrace

  File "/Users/arxell/repo/mdcm/alfa/venv39/lib/python3.9/site-packages/fastapi/applications.py", line 143, in openapi
    return JSONResponse(self.openapi())
  File "/Users/arxell/repo/mdcm/alfa/venv39/lib/python3.9/site-packages/fastapi/applications.py", line 121, in openapi
    self.openapi_schema = get_openapi(
  File "/Users/arxell/repo/mdcm/alfa/venv39/lib/python3.9/site-packages/fastapi/openapi/utils.py", line 348, in get_openapi
    definitions = get_model_definitions(
  File "/Users/arxell/repo/mdcm/alfa/venv39/lib/python3.9/site-packages/fastapi/utils.py", line 31, in get_model_definitions
    model_name = model_name_map[model]
KeyError: <enum 'EnumExample'>

Environment

• OS: macOS
• FastAPI: 0.62.0
• Python: 3.9.0
• pydantic: 1.7.3

[includeamin]

#2061

[includeamin]

#1986

[brumar]

We had the same problem, updating to fastapi to 0.65 worked for us.

[Sailokeshg]

We had the same problem, updating to fastapi to 0.65 worked for us.

How do i update existing version of fastapi to latest in ubuntu. I'm getting some errors when using pip install fastapi

[JarroVGIT]

Either uninstall it first, or use pip install fastapi --upgrade

[Sailokeshg]

That worked Successfully installed fastapi-0.78.0 starlette-0.19.1 , but in http://127.0.0.1:8000/openapi.json . it is still showing version of fastapi as "0.1.0"

[JarroVGIT]

That is not the version of FastAPI, but the default version of your API itself. You can set the version like so:

app = FastAPI(version='15.0.3')

When not setting a version when initiating a FastAPI() application, it defaults to 0.1.0 which you will see in the docs. See also: https://fastapi.tiangolo.com/tutorial/metadata/?h=version#metadata-for-api