Pydantic parsing derived classes

README.md

You can also check the official documentation and example here https://pydantic-docs.helpmanual.io/usage/types/#literal-type

main.py

from typing import Union

from pydantic import parse_obj_as

from models import LocalRepo, RemoteRepo, VirtualRepo

local = {
  "rclass": "local",
  "name": "local-repo"
}


remote = {
  "rclass": "remote",
  "name": "remote-repo"
}


virtual = {
  "rclass": "virtual",
  "name": "virtual-repo"
}

local_repository = parse_obj_as(Union[LocalRepo, RemoteRepo, VirtualRepo], local)
remote_repository = parse_obj_as(Union[LocalRepo, RemoteRepo, VirtualRepo], remote)
virtual_repository = parse_obj_as(Union[LocalRepo, RemoteRepo, VirtualRepo], virtual)

print(type(local_repository).__name__)
print(type(remote_repository).__name__)
print(type(virtual_repository).__name__)

models.py

from enum import Enum
from typing_extensions import Literal

from pydantic import BaseModel

class RclassEnum(str, Enum):
  local = "local"
  remote = "remote"
  virtual = "virtual"

class BaseRepo(BaseModel):
  rclass: RclassEnum
  name: str

class LocalRepo(BaseRepo):
  rclass: Literal[RclassEnum.local] = RclassEnum.local


class RemoteRepo(BaseRepo):
  rclass: Literal[RclassEnum.remote] = RclassEnum.remote


class VirtualRepo(BaseRepo):
  rclass: Literal[RclassEnum.virtual] = RclassEnum.virtual