用Python开发粮食收购平台的简洁实现方案，采用分层架构设计并遵循高可维护性原则-优快云博客

以下是用Python开发粮食收购平台的简洁实现方案，采用分层架构设计并遵循高可维护性原则：

技术选型

Web框架：Django (自带ORM/Admin/安全防护)
数据库：PostgreSQL (支持JSON字段和地理查询)
异步任务：Celery + Redis
前端：Vue.js 3 (前后端分离)

核心模块设计

# models.py
class Farmer(models.Model):
    user = models.OneToOneField(User, on_delete=models.CASCADE)
    location = models.PointField()
    rating = models.FloatField(default=5.0)

class GrainType(models.Model):
    name = models.CharField(max_length=50)  # 小麦/玉米/水稻等
    quality_standard = models.JSONField()

class PurchaseOrder(models.Model):
    STATUS_CHOICES = [('pending', '待验收'), ('completed', '已完成'), ('canceled', '已取消')]
    
    farmer = models.ForeignKey(Farmer, on_delete=models.CASCADE)
    grain_type = models.ForeignKey(GrainType, on_delete=models.PROTECT)
    quantity = models.DecimalField(max_digits=10, decimal_places=2)  # 吨
    price = models.DecimalField(max_digits=10, decimal_places=2)
    status = models.CharField(max_length=20, choices=STATUS_CHOICES)
    quality_check = models.JSONField(null=True)

业务逻辑层示例

# services/purchase.py
class PurchaseService:
    @transaction.atomic
    def create_order(self, farmer_id, grain_data):
        farmer = Farmer.objects.get(id=farmer_id)
        grain_type = GrainType.objects.get(id=grain_data['type_id'])
        
        order = PurchaseOrder.objects.create(
            farmer=farmer,
            grain_type=grain_type,
            quantity=grain_data['quantity'],
            price=self._calculate_price(grain_type, farmer.rating),
            status='pending'
        )
        
        self._send_quality_check_task.delay(order.id)
        return order

    @staticmethod
    def _calculate_price(grain_type, farmer_rating):
        base_price = grain_type.base_price
        return base_price * (0.9 + farmer_rating * 0.02)

    @shared_task
    def _send_quality_check_task(order_id):
        # 调用第三方质量检测服务
        pass

API接口示例（DRF）

# api/views.py
class OrderAPI(GenericAPIView):
    serializer_class = OrderSerializer
    permission_classes = [IsAuthenticated]

    def post(self, request):
        serializer = self.get_serializer(data=request.data)
        serializer.is_valid(raise_exception=True)
        
        service = PurchaseService()
        order = service.create_order(
            request.user.farmer.id,
            serializer.validated_data
        )
        
        return Response(OrderSerializer(order).data, status=201)

运维部署建议

# 使用Docker编排
version: '3'
services:
  web:
    image: django:4.2
    command: gunicorn core.wsgi:application --bind 0.0.0.0:8000
    volumes:
      - .:/code
    depends_on:
      - redis
      - db

  db:
    image: postgres:15
    environment:
      POSTGRES_DB: grain
      POSTGRES_USER: admin
      POSTGRES_PASSWORD: securepass

  redis:
    image: redis:7

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