{ "cells": [ { "cell_type": "code", "execution_count": 1, "metadata": {}, "outputs": [ { "data": { "text/plain": [ "Item(name='iPhone', price=0, number=0, categories=[Category(name='', level=1)])" ] }, "execution_count": 1, "metadata": {}, "output_type": "execute_result" } ], "source": [ "import typing as t\n", "\n", "from pydantic import BaseModel\n", "\n", "\n", "class Category(BaseModel):\n", " name: str = \"\"\n", " level: int = 1\n", "\n", "\n", "class Item(BaseModel):\n", " name: str\n", " price: t.Union[int, float] = 0\n", " number: int = 0\n", " categories: t.List[Category] = [Category()]\n", "\n", "\n", "Item(name=\"iPhone\")\n", "Item(name='iPhone', price=0, number=0, categories=[Category(name='', level=1)])" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## 额外的类型注解" ] }, { "cell_type": "code", "execution_count": 2, "metadata": {}, "outputs": [], "source": [ "from pydantic import BaseModel, FilePath, HttpUrl, IPvAnyAddress, PostgresDsn\n", "from pydantic.color import Color\n", "\n", "class FileSystem(BaseModel):\n", " path: FilePath\n", "\n", "\n", "class Link(BaseModel):\n", " url: HttpUrl\n", "\n", "\n", "class Network(BaseModel):\n", " ip: IPvAnyAddress\n", "\n", "\n", "class PostgreDatabase(BaseModel):\n", " dsn: PostgresDsn\n", "\n", "\n", "class WebColor(BaseModel):\n", " value: Color" ] }, { "cell_type": "code", "execution_count": 3, "metadata": {}, "outputs": [ { "data": { "text/plain": [ "Item(name='iphone', number=0)" ] }, "execution_count": 3, "metadata": {}, "output_type": "execute_result" } ], "source": [ "from pydantic import constr, conint\n", "\n", "class Item(BaseModel):\n", " name: constr(strip_whitespace=True, min_length=2, max_length=10)\n", " number: conint(ge=0) = 0\n", "\n", "\n", "Item(name=\" iphone \")\n" ] }, { "cell_type": "code", "execution_count": 4, "metadata": {}, "outputs": [], "source": [ "# Item(name=\"iPhone\", number=-1) # raise ValidationError here!" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## 数据校验" ] }, { "cell_type": "code", "execution_count": 5, "metadata": {}, "outputs": [], "source": [ "import typing as t\n", "from dataclasses import dataclass\n", "from pydantic import BaseModel, validator\n", "\n", "@dataclass\n", "class Category:\n", " level: int = 1\n", " name: str = \"\"\n", "\n", "class Item(BaseModel):\n", " name: str\n", " price: t.Union[int, float] = 0\n", " number: int = 0\n", " categories: t.List[Category] = [Category()]\n", "\n", "\n", " @validator(\"price\", \"number\")\n", " def prevent_negative_number(cls, v):\n", " if v < 0:\n", " raise ValueError(\"can't set a negative number\")\n", " return v" ] }, { "cell_type": "code", "execution_count": 6, "metadata": {}, "outputs": [], "source": [ "# Item(name=\"iPhone\", price=-1) # raise ValidationError here!" ] }, { "cell_type": "code", "execution_count": 7, "metadata": {}, "outputs": [], "source": [ "import typing as t\n", "from dataclasses import field\n", "\n", "from pydantic import validator\n", "from pydantic.dataclasses import dataclass # <-- use pydantic.dataclasses.dataclass\n", "\n", "\n", "@dataclass\n", "class Category:\n", " name: str = \"\"\n", " level: int = 1\n", "\n", "\n", "def default_categories():\n", " return [Category()]\n", "\n", "\n", "@dataclass\n", "class Item:\n", " name: str\n", " price: t.Union[int, float] = field(default=0)\n", " number: int = field(default=0)\n", " categories: t.List[Category] = field(default_factory=default_categories)\n", "\n", " @validator(\"price\", \"number\")\n", " def prevent_negative_number(cls, v):\n", " if v < 0:\n", " raise ValueError(\"can't set a negative number\")\n", " return v" ] }, { "cell_type": "code", "execution_count": 8, "metadata": {}, "outputs": [], "source": [ "import typing as t\n", "\n", "from pydantic import BaseModel, validator\n", "from pydantic.dataclasses import dataclass\n", "\n", "\n", "@dataclass\n", "class Category:\n", " name: str = \"\"\n", " level: int = 1\n", "\n", "\n", "\n", "class ItemCode(str):\n", " @classmethod\n", " def __get_validators__(cls):\n", " yield cls.validate\n", "\n", " @classmethod\n", " def validate(cls, v):\n", " if not v.startswith(\"ITEM\"):\n", " raise ValueError(\"invalid item code format\")\n", " return v\n", "\n", "\n", "class Item(BaseModel):\n", " name: str\n", " itemcode: ItemCode\n", " price: t.Union[int, float] = 0\n", " number: int = 0\n", " categories: t.List[Category] = [Category()]\n", "\n", " @validator(\"price\", \"number\")\n", " def prevent_negative_number(cls, v):\n", " if v < 0:\n", " raise ValueError(\"can't set a negative number\")\n", " return v" ] }, { "cell_type": "code", "execution_count": 9, "metadata": {}, "outputs": [ { "data": { "text/plain": [ "Item(name='iPhone', itemcode='ITEM31415926', price=0, number=0, categories=[Category(name='', level=1)])" ] }, "execution_count": 9, "metadata": {}, "output_type": "execute_result" } ], "source": [ "Item(name=\"iPhone\", itemcode=\"ITEM31415926\")" ] }, { "cell_type": "code", "execution_count": 10, "metadata": {}, "outputs": [], "source": [ "# Item(name=\"iPhone\", itemcode=\"aabbcc\") # raise ValidationError here!" ] }, { "cell_type": "code", "execution_count": 11, "metadata": {}, "outputs": [], "source": [ "import typing as t\n", "\n", "from pydantic import BaseModel, validator\n", "from pydantic.dataclasses import dataclass\n", "\n", "\n", "class ItemValidator:\n", " @classmethod\n", " def prevent_negative_number(cls, v):\n", " if v < 0:\n", " raise ValueError(\"can't set a negative number\")\n", " return v\n", "\n", " @classmethod\n", " def has_itemcode_preffix(cls, v: str):\n", " if not v.startswith(\"ITEM\"):\n", " raise ValueError(\"invalid item code format\")\n", " return v\n", "\n", "\n", "@dataclass\n", "class Category:\n", " name: str = \"\"\n", " level: int = 1\n", "\n", "\n", "\n", "class Item(BaseModel):\n", " name: str\n", " itemcode: str\n", " price: t.Union[int, float] = 0\n", " number: int = 0\n", " categories: t.List[Category] = [Category()]\n", "\n", " check_number = validator(\"price\", \"number\")(ItemValidator.prevent_negative_number)\n", " check_itemcode = validator(\"itemcode\")(ItemValidator.has_itemcode_preffix)" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## 导出数据类" ] }, { "cell_type": "code", "execution_count": 12, "metadata": {}, "outputs": [], "source": [ "import typing as t\n", "\n", "from pydantic import BaseModel\n", "\n", "\n", "class Category(BaseModel):\n", " name: str = \"\"\n", " level: int = 1\n", "\n", "\n", "class Item(BaseModel):\n", " name: str\n", " price: t.Union[int, float] = 0\n", " number: int = 0\n", " categories: t.List[Category] = [Category()]\n", "\n", "\n", "item = Item(\n", " name=\"iPhone\",\n", " price=6999,\n", " number=1000,\n", " categories=[Category(name=\"Phone\")],\n", ")\n" ] }, { "cell_type": "code", "execution_count": 13, "metadata": {}, "outputs": [ { "data": { "text/plain": [ "{'name': 'iPhone',\n", " 'price': 6999,\n", " 'number': 1000,\n", " 'categories': [{'name': 'Phone', 'level': 1}]}" ] }, "execution_count": 13, "metadata": {}, "output_type": "execute_result" } ], "source": [ "item.dict()" ] }, { "cell_type": "code", "execution_count": 14, "metadata": {}, "outputs": [ { "data": { "text/plain": [ "'{\"name\": \"iPhone\", \"price\": 6999, \"number\": 1000, \"categories\": [{\"name\": \"Phone\", \"level\": 1}]}'" ] }, "execution_count": 14, "metadata": {}, "output_type": "execute_result" } ], "source": [ "item.json()" ] }, { "cell_type": "code", "execution_count": 15, "metadata": {}, "outputs": [ { "data": { "text/plain": [ "{'name': 'iPhone',\n", " 'price': 6999,\n", " 'categories': [{'name': 'Phone', 'level': 1}]}" ] }, "execution_count": 15, "metadata": {}, "output_type": "execute_result" } ], "source": [ "item.dict(exclude={\"number\": True})" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## 从 ORM 中进行转换" ] }, { "cell_type": "code", "execution_count": 16, "metadata": {}, "outputs": [], "source": [ "import typing as t\n", "from datetime import datetime\n", "\n", "import peewee as pw\n", "from pydantic import BaseModel, Field\n", "\n", "db = pw.SqliteDatabase(\":memory:\")\n", "\n", "\n", "class NoteORM(pw.Model):\n", " id = pw.AutoField()\n", " title = pw.CharField()\n", " content = pw.TextField()\n", " tags = pw.CharField()\n", " create_at = pw.DateTimeField(default=datetime.now())\n", "\n", " class Meta:\n", " database = db\n", "\n", "\n", "class NoteModel(BaseModel):\n", " id: t.Optional[int] = Field(example=\"null\")\n", " title: str\n", " content: str\n", " tags: t.Optional[t.List[str]] = Field(example=\"null\")\n", "\n", " class Config:\n", " orm_mode = True" ] }, { "cell_type": "code", "execution_count": 17, "metadata": {}, "outputs": [ { "data": { "text/plain": [ "{'id': None, 'title': '测试', 'content': '# Hello, world\\n', 'tags': ['技术分享']}" ] }, "execution_count": 17, "metadata": {}, "output_type": "execute_result" } ], "source": [ "note_db = NoteORM(title=\"测试\", content=\"# Hello, world\\n\", tags=[\"技术分享\"])\n", "note = NoteModel.from_orm(note_db)\n", "note.dict()" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [] } ], "metadata": { "kernelspec": { "display_name": "Python 3.9.0 ('pandas-startup')", "language": "python", "name": "python3" }, "language_info": { "codemirror_mode": { "name": "ipython", "version": 3 }, "file_extension": ".py", "mimetype": "text/x-python", "name": "python", "nbconvert_exporter": "python", "pygments_lexer": "ipython3", "version": "3.9.0" }, "orig_nbformat": 4, "vscode": { "interpreter": { "hash": "13977d4cc82dee5f9d9535ceb495bd0ab12a43c33c664e5f0d53c24cf634b67f" } } }, "nbformat": 4, "nbformat_minor": 2 }