Django+MySQL接口开发完全指南

前言

本文将详细介绍如何使用Django结合MySQL数据库开发RESTful API接口。我们将从环境搭建开始，一步步实现一个完整的接口项目。

环境准备

首先需要安装以下组件：

• Python 3.8+
• Django 4.2
• MySQL 8.0
• mysqlclient
• djangorestframework

安装命令

# 创建虚拟环境
python -m venv venv
source venv/bin/activate  # Windows使用 venv\Scripts\activate# 安装依赖
pip install django==4.2
pip install mysqlclient
pip install djangorestframework

项目创建与配置

1. 创建项目

django-admin startproject myproject
cd myproject
python manage.py startapp api

2. 配置settings.py

INSTALLED_APPS = ['django.contrib.admin','django.contrib.auth','django.contrib.contenttypes','django.contrib.sessions','django.contrib.messages','django.contrib.staticfiles','rest_framework',  # 添加rest_framework'api',  # 添加api应用
]# 数据库配置
DATABASES = {'default': {'ENGINE': 'django.db.backends.mysql','NAME': 'django_demo','USER': 'root','PASSWORD': 'your_password','HOST': '127.0.0.1','PORT': '3306',}
}# REST框架配置
REST_FRAMEWORK = {'DEFAULT_PAGINATION_CLASS': 'rest_framework.pagination.PageNumberPagination','PAGE_SIZE': 10,
}

数据库模型设计

1. 创建模型（api/models.py）

from django.db import modelsclass Book(models.Model):title = models.CharField(max_length=100, verbose_name='书名')author = models.CharField(max_length=50, verbose_name='作者')price = models.DecimalField(max_digits=5, decimal_places=2, verbose_name='价格')publish_date = models.DateField(verbose_name='出版日期')created_at = models.DateTimeField(auto_now_add=True, verbose_name='创建时间')updated_at = models.DateTimeField(auto_now=True, verbose_name='更新时间')class Meta:db_table = 'books'verbose_name = '图书'verbose_name_plural = verbose_nameordering = ['-created_at']def __str__(self):return self.title

2. 生成并应用数据库迁移

python manage.py makemigrations
python manage.py migrate

序列化器开发

1. 创建序列化器（api/serializers.py）

from rest_framework import serializers
from .models import Bookclass BookSerializer(serializers.ModelSerializer):class Meta:model = Bookfields = ['id', 'title', 'author', 'price', 'publish_date', 'created_at', 'updated_at']read_only_fields = ['created_at', 'updated_at']

视图开发

1. 创建视图（api/views.py）

from rest_framework import viewsets, filters
from rest_framework.response import Response
from rest_framework.decorators import action
from django_filters.rest_framework import DjangoFilterBackend
from .models import Book
from .serializers import BookSerializerclass BookViewSet(viewsets.ModelViewSet):queryset = Book.objects.all()serializer_class = BookSerializerfilter_backends = [DjangoFilterBackend, filters.SearchFilter, filters.OrderingFilter]filterset_fields = ['author']search_fields = ['title', 'author']ordering_fields = ['price', 'publish_date']@action(detail=False, methods=['get'])def get_book_stats(self, request):"""获取图书统计信息"""total_books = Book.objects.count()total_authors = Book.objects.values('author').distinct().count()avg_price = Book.objects.aggregate(avg_price=models.Avg('price'))return Response({'total_books': total_books,'total_authors': total_authors,'average_price': avg_price['avg_price']})

URL配置

1. 配置项目URLs（myproject/urls.py）

from django.contrib import admin
from django.urls import path, include
from rest_framework.routers import DefaultRouter
from api.views import BookViewSetrouter = DefaultRouter()
router.register(r'books', BookViewSet)urlpatterns = [path('admin/', admin.site.urls),path('api/', include(router.urls)),
]

中间件开发

1. 创建自定义中间件（api/middleware.py）

import time
from django.utils.deprecation import MiddlewareMixin
import logginglogger = logging.getLogger(__name__)class RequestLogMiddleware(MiddlewareMixin):def process_request(self, request):request.start_time = time.time()def process_response(self, request, response):if hasattr(request, 'start_time'):duration = time.time() - request.start_timelogger.info(f'{request.method} {request.path} - {response.status_code} - {duration:.2f}s')return response

2. 在settings.py中注册中间件

MIDDLEWARE = ['django.middleware.security.SecurityMiddleware','django.contrib.sessions.middleware.SessionMiddleware','django.middleware.common.CommonMiddleware','django.middleware.csrf.CsrfViewMiddleware','django.contrib.auth.middleware.AuthenticationMiddleware','django.contrib.messages.middleware.MessageMiddleware','django.middleware.clickjacking.XFrameOptionsMiddleware','api.middleware.RequestLogMiddleware',  # 添加自定义中间件
]

异常处理

1. 创建自定义异常处理（api/exceptions.py）

from rest_framework.views import exception_handler
from rest_framework.response import Response
from rest_framework import statusdef custom_exception_handler(exc, context):response = exception_handler(exc, context)if response is None:return Response({'error': str(exc),'message': '服务器内部错误'}, status=status.HTTP_500_INTERNAL_SERVER_ERROR)return response

2. 在settings.py中配置异常处理器

REST_FRAMEWORK = {'EXCEPTION_HANDLER': 'api.exceptions.custom_exception_handler'
}

API接口测试

1. 创建测试用例（api/tests.py）

from rest_framework.test import APITestCase
from rest_framework import status
from .models import Book
from datetime import dateclass BookTests(APITestCase):def setUp(self):self.book_data = {'title': 'Django实战','author': '张三','price': '59.99','publish_date': '2024-01-01'}self.book = Book.objects.create(**self.book_data)def test_create_book(self):"""测试创建图书"""response = self.client.post('/api/books/', self.book_data, format='json')self.assertEqual(response.status_code, status.HTTP_201_CREATED)self.assertEqual(Book.objects.count(), 2)def test_get_book_list(self):"""测试获取图书列表"""response = self.client.get('/api/books/')self.assertEqual(response.status_code, status.HTTP_200_OK)self.assertEqual(len(response.data['results']), 1)

API接口文档

使用drf-yasg生成Swagger文档：

1. 安装drf-yasg

pip install drf-yasg

2. 配置settings.py

INSTALLED_APPS = [...'drf_yasg',
]

3. 配置URLs（myproject/urls.py）

from django.urls import path, include, re_path
from rest_framework import permissions
from drf_yasg.views import get_schema_view
from drf_yasg import openapischema_view = get_schema_view(openapi.Info(title="图书管理API",default_version='v1',description="图书管理系统API文档",terms_of_service="https://www.yourapp.com/terms/",contact=openapi.Contact(email="contact@yourapp.com"),license=openapi.License(name="BSD License"),),public=True,permission_classes=(permissions.AllowAny,),
)urlpatterns = [...re_path(r'^swagger(?P<format>\.json|\.yaml)$', schema_view.without_ui(cache_timeout=0), name='schema-json'),path('swagger/', schema_view.with_ui('swagger', cache_timeout=0), name='schema-swagger-ui'),path('redoc/', schema_view.with_ui('redoc', cache_timeout=0), name='schema-redoc'),
]

接口使用示例

1. 创建图书

curl -X POST http://localhost:8000/api/books/ \-H "Content-Type: application/json" \-d '{"title":"Django实战","author":"张三","price":"59.99","publish_date":"2024-01-01"}'

2. 获取图书列表

curl http://localhost:8000/api/books/

3. 更新图书

curl -X PUT http://localhost:8000/api/books/1/ \-H "Content-Type: application/json" \-d '{"title":"Django实战（第二版）","author":"张三","price":"69.99","publish_date":"2024-01-01"}'

4. 删除图书

curl -X DELETE http://localhost:8000/api/books/1/

性能优化建议

1. 使用数据库索引

   class Book(models.Model):...class Meta:indexes = [models.Index(fields=['title']),models.Index(fields=['author']),]

2. 使用缓存

   from django.core.cache import cacheclass BookViewSet(viewsets.ModelViewSet):def list(self, request):cache_key = 'book_list'cached_data = cache.get(cache_key)if cached_data is None:queryset = self.filter_queryset(self.get_queryset())serializer = self.get_serializer(queryset, many=True)cached_data = serializer.datacache.set(cache_key, cached_data, timeout=300)  # 缓存5分钟return Response(cached_data)

总结

本文详细介绍了使用Django开发RESTful API的完整流程，包括：

1. 环境搭建和项目配置
2. 数据库模型设计
3. 序列化器开发
4. 视图和URL配置
5. 中间件和异常处理
6. 测试用例编写
7. API文档生成
8. 性能优化建议

通过按照本教程的步骤，你可以快速搭建一个功能完善的Django API项目。建议在实际开发中根据具体需求进行适当调整和扩展。