dictaclass 0.6.0

Convert heirarchies of dicts/list/sets/values (JSON?) to heirarchies of type annotated dataclasses.

dictaclass - dicts to dataclasses

Have you ever been handed an "example JSON" and wanted to have it in an intellisense-friendly structure? Just define the JSON structure as a hierarchy of dataclasses and run to_dataclass(MyJsonDataclass, json.loads(source))

Well, the library works with whatever source of data you have, as long as you can represent the way json.loads does - dicts, lists, and values.

Features

• Supports deeply nested dataclasses (duh)
• Supports inheritance
• Supports collections
  • list
  • set
  • dict
• Supports frozen dataclasses
• Supports timestamps as datetime objects

Limitations

• Requires Python 3.7+
• Cannot guess types.
• Cannot use mixed types.
• Cannot use Union[].
• Cannot use Tuple[].

Installation

py -m pip install dictaclass

or

python3 -m pip install dictaclass

Example

from typing import Set

from dataclasses import dataclass
from dictaclass import to_dataclass

import json

@dataclass(frozen=True)
class Pair:
    first: str
    last: str

@dataclass(frozen=True)
class PairPair:
    a: Pair

@dataclass(frozen=True)
class Object:
    pairs: Set[PairPair]

v = to_dataclass(
    Object,
    {
        "pairs": [
            {"a": {"first": "f0", "last": "l0"}},
            {"a": {"first": "f1", "last": "l1"}},
        ]
    },
)
# or
v = to_dataclass(
    Object,
    json.loads(
        """
        {
            "pairs": [
                {"a": {"first": "f0", "last": "l0"}},
                {"a": {"first": "f1", "last": "l1"}}
            ]
        }
        """
    ),
)

assert isinstance(v, Object)
assert isinstance(v.pairs, set) # it was a list in the JSON
assert len(v.pairs) == 2
assert v.pairs == {
    PairPair(Pair("f0", "l0")),
    PairPair(Pair("f1", "l1"))
}