Pydantic vs cattrs Deserialization Benchmark

pydantic_vs_cattrs.ipynb

{
 "cells": [
  {
   "cell_type": "code",
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   "metadata": {},
   "outputs": [],
   "source": [
    "from attrs import define, field\n",
    "from cattrs.gen import make_dict_structure_fn, make_dict_unstructure_fn, override\n",
    "from cattrs.preconf.orjson import make_converter\n",
    "from pydantic import ConfigDict, Field, TypeAdapter\n",
    "from pydantic.dataclasses import dataclass\n",
    "\n",
    "\n",
    "# attrs/cattrs\n",
    "@define\n",
    "class UserAttrs:\n",
    "    name: str = field(metadata={\"rename\": \"userName\"})\n",
    "\n",
    "\n",
    "converter = make_converter()\n",
    "unst_hook = make_dict_unstructure_fn(\n",
    "    UserAttrs, converter, name=override(rename=\"userName\")\n",
    ")\n",
    "st_hook = make_dict_structure_fn(UserAttrs, converter, name=override(rename=\"userName\"))\n",
    "converter.register_unstructure_hook(UserAttrs, unst_hook)\n",
    "converter.register_structure_hook(UserAttrs, st_hook)\n",
    "\n",
    "# pydantic\n",
    "@dataclass(config=ConfigDict(populate_by_name=True))\n",
    "class UserPydanticDataclass:\n",
    "    name: str = Field(validation_alias=\"userName\", serialization_alias=\"userName\")\n",
    "\n",
    "\n",
    "type_adapter = TypeAdapter(UserPydanticDataclass)\n",
    "\n",
    "# data\n",
    "json_literal = b'{\"userName\":\"Alice\"}'"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "949 ns ± 46.1 ns per loop (mean ± std. dev. of 7 runs, 1,000,000 loops each)\n"
     ]
    }
   ],
   "source": [
    "%timeit type_adapter.validate_json(json_literal)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "1.42 μs ± 55.3 ns per loop (mean ± std. dev. of 7 runs, 1,000,000 loops each)\n"
     ]
    }
   ],
   "source": [
    "%timeit converter.loads(json_literal, UserAttrs)"
   ]
  }
 ],
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