Add mixin example

Author: sozykin

15/15_mixin.ipynb

@@ -0,0 +1,110 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Mixin"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "Описываем класс Mixin для чтения параметров из конфигурационного файла"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "import configparser\n",
+    "from pathlib import Path\n",
+    "    \n",
+    "class SettingsFileMixin:\n",
+    "    # Путь к конфигурационному файле\n",
+    "    settings_path = Path('my_program.conf')\n",
+    "    # Парсер параметров\n",
+    "    config = configparser.ConfigParser()\n",
+    "\n",
+    "    def read_setting(self, key):\n",
+    "        # Читаем файл с параметрами\n",
+    "        self.config.read(self.settings_path)\n",
+    "        try:\n",
+    "            # Возвращаем нужный параметр\n",
+    "            # Атрибут settings_section не определен в Mixin \n",
+    "            return self.config[self.settings_section][key]\n",
+    "        except KeyError:\n",
+    "            raise KeyError(\"Неправильная секция в файле конфигурации\")"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "Создаем класс, наследуемый от Mixin"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "class DbController(SettingsFileMixin):\n",
+    "    def __init__(self):\n",
+    "        # Определяем атрибут, которого не хватает в Mixin\n",
+    "        self.settings_section = 'DATABASE'\n",
+    "\n",
+    "    def connect(self):\n",
+    "        # Вызываем методы класса Mixin\n",
+    "        hostname = self.read_setting('HostName')\n",
+    "        username = self.read_setting('UserName')\n",
+    "        password = self.read_setting('Password')\n",
+    "        print(f'Параметры соединения с базой данных: {hostname}, {username}, {password}')"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "d = DbController()"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "d.connect()"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": ".venv",
+   "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": "3.11.1"
+  },
+  "orig_nbformat": 4
+ },
+ "nbformat": 4,
+ "nbformat_minor": 2
+}