feat: 种类属性管理，支持定义属性模板和商品属性值

src/main/java/com/example/building/controller/CategoryAttributeController.java

@@ -0,0 +1,37 @@
+package com.example.building.controller;
+
+import com.example.building.common.Result;
+import com.example.building.entity.CategoryAttribute;
+import com.example.building.service.CategoryAttributeService;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.web.bind.annotation.*;
+
+import java.util.List;
+
+/**
+ * 种类属性控制器
+ */
+@RestController
+@RequestMapping("/api/v1/category-attributes")
+public class CategoryAttributeController {
+
+    @Autowired
+    private CategoryAttributeService categoryAttributeService;
+
+    /**
+     * 获取种类的属性列表
+     */
+    @GetMapping("/category/{categoryId}")
+    public Result<List<CategoryAttribute>> getByCategoryId(@PathVariable String categoryId) {
+        return Result.success(categoryAttributeService.getByCategoryId(categoryId));
+    }
+
+    /**
+     * 保存种类属性
+     */
+    @PostMapping("/category/{categoryId}")
+    public Result<Void> saveAttributes(@PathVariable String categoryId, @RequestBody List<CategoryAttribute> attrs) {
+        categoryAttributeService.saveAttributes(categoryId, attrs);
+        return Result.success();
+    }
+}

src/main/java/com/example/building/controller/ProductController.java

@@ -5,6 +5,8 @@ import com.example.building.common.Result;
 import com.example.building.entity.Category;
 import com.example.building.entity.Product;
 import com.example.building.service.ProductService;
+import com.example.building.service.CategoryAttributeService;
+import com.example.building.service.ProductAttributeService;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.web.bind.annotation.*;
 
@@ -22,6 +24,12 @@ public class ProductController {
     @Autowired
     private ProductService productService;
 
+    @Autowired
+    private CategoryAttributeService categoryAttributeService;
+
+    @Autowired
+    private ProductAttributeService productAttributeService;
+
     /**
      * 获取分类列表
      */
@@ -131,4 +139,52 @@ public class ProductController {
     public Result<List<Map<String, Object>>> getStockAlerts() {
         return Result.success(productService.getStockAlerts());
     }
+
+    // ============ 属性相关 ============
+
+    /**
+     * 获取种类的属性定义
+     */
+    @GetMapping("/categories/{categoryId}/attributes")
+    public Result<List> getCategoryAttributes(@PathVariable String categoryId) {
+        return Result.success(categoryAttributeService.getByCategoryId(categoryId));
+    }
+
+    /**
+     * 保存种类的属性定义
+     */
+    @PostMapping("/categories/{categoryId}/attributes")
+    public Result<Void> saveCategoryAttributes(
+            @PathVariable String categoryId,
+            @RequestBody List attributes,
+            @RequestHeader(value = "X-User-Role", required = false) String role) {
+        if (!"admin".equals(role)) {
+            return Result.error("只有管理员可以操作");
+        }
+        categoryAttributeService.saveAttributes(categoryId, attributes);
+        return Result.success();
+    }
+
+    /**
+     * 获取商品的属性值
+     */
+    @GetMapping("/{productId}/attributes")
+    public Result<List> getProductAttributes(@PathVariable String productId) {
+        return Result.success(productAttributeService.getByProductId(productId));
+    }
+
+    /**
+     * 保存商品的属性值
+     */
+    @PostMapping("/{productId}/attributes")
+    public Result<Void> saveProductAttributes(
+            @PathVariable String productId,
+            @RequestBody List<Map<String, Object>> attrs,
+            @RequestHeader(value = "X-User-Role", required = false) String role) {
+        if (!"admin".equals(role)) {
+            return Result.error("只有管理员可以操作");
+        }
+        productAttributeService.saveProductAttributes(productId, attrs);
+        return Result.success();
+    }
 }

src/main/java/com/example/building/entity/CategoryAttribute.java

@@ -0,0 +1,58 @@
+package com.example.building.entity;
+
+import com.baomidou.mybatisplus.annotation.*;
+import lombok.Data;
+
+import java.time.LocalDateTime;
+
+/**
+ * 种类属性定义实体
+ */
+@Data
+@TableName("category_attributes")
+public class CategoryAttribute {
+
+    @TableId(type = IdType.ASSIGN_UUID)
+    private String attrId;
+
+    /**
+     * 种类ID
+     */
+    private String categoryId;
+
+    /**
+     * 属性名称
+     */
+    private String name;
+
+    /**
+     * 属性类型: number=数字, text=文本, formula=公式
+     */
+    private String attrType;
+
+    /**
+     * 单位
+     */
+    private String unit;
+
+    /**
+     * 公式表达式（如：length*width）
+     */
+    private String formula;
+
+    /**
+     * 排序
+     */
+    private Integer sortOrder;
+
+    /**
+     * 是否必填
+     */
+    private Integer required;
+
+    @TableField(fill = FieldFill.INSERT)
+    private LocalDateTime createdAt;
+
+    @TableField(fill = FieldFill.INSERT_UPDATE)
+    private LocalDateTime updatedAt;
+}

src/main/java/com/example/building/entity/ProductAttribute.java

@@ -0,0 +1,40 @@
+package com.example.building.entity;
+
+import com.baomidou.mybatisplus.annotation.*;
+import lombok.Data;
+
+import java.time.LocalDateTime;
+
+/**
+ * 商品属性值实体
+ */
+@Data
+@TableName("product_attributes")
+public class ProductAttribute {
+
+    @TableId(type = IdType.ASSIGN_UUID)
+    private String id;
+
+    /**
+     * 商品ID
+     */
+    private String productId;
+
+    /**
+     * 属性定义ID
+     */
+    private String attrId;
+
+    /**
+     * 属性名称（冗余）
+     */
+    private String attrName;
+
+    /**
+     * 属性值
+     */
+    private String attrValue;
+
+    @TableField(fill = FieldFill.INSERT)
+    private LocalDateTime createdAt;
+}

src/main/java/com/example/building/mapper/CategoryAttributeMapper.java

@@ -0,0 +1,9 @@
+package com.example.building.mapper;
+
+import com.baomidou.mybatisplus.core.mapper.BaseMapper;
+import com.example.building.entity.CategoryAttribute;
+import org.apache.ibatis.annotations.Mapper;
+
+@Mapper
+public interface CategoryAttributeMapper extends BaseMapper<CategoryAttribute> {
+}

src/main/java/com/example/building/mapper/ProductAttributeMapper.java

@@ -0,0 +1,9 @@
+package com.example.building.mapper;
+
+import com.baomidou.mybatisplus.core.mapper.BaseMapper;
+import com.example.building.entity.ProductAttribute;
+import org.apache.ibatis.annotations.Mapper;
+
+@Mapper
+public interface ProductAttributeMapper extends BaseMapper<ProductAttribute> {
+}

src/main/java/com/example/building/service/CategoryAttributeService.java

@@ -0,0 +1,26 @@
+package com.example.building.service;
+
+import com.example.building.entity.CategoryAttribute;
+import com.baomidou.mybatisplus.extension.service.IService;
+import java.util.List;
+
+/**
+ * 种类属性服务接口
+ */
+public interface CategoryAttributeService extends IService<CategoryAttribute> {
+
+    /**
+     * 获取种类的所有属性
+     */
+    List<CategoryAttribute> getByCategoryId(String categoryId);
+
+    /**
+     * 保存属性
+     */
+    void saveAttributes(String categoryId, List<CategoryAttribute> attrs);
+
+    /**
+     * 删除种类的所有属性
+     */
+    void deleteByCategoryId(String categoryId);
+}

src/main/java/com/example/building/service/ProductAttributeService.java

@@ -0,0 +1,27 @@
+package com.example.building.service;
+
+import com.example.building.entity.ProductAttribute;
+import com.baomidou.mybatisplus.extension.service.IService;
+import java.util.List;
+import java.util.Map;
+
+/**
+ * 商品属性服务接口
+ */
+public interface ProductAttributeService extends IService<ProductAttribute> {
+
+    /**
+     * 获取商品的属性值
+     */
+    List<ProductAttribute> getByProductId(String productId);
+
+    /**
+     * 保存商品属性值
+     */
+    void saveProductAttributes(String productId, List<Map<String, Object>> attrs);
+
+    /**
+     * 删除商品的所有属性
+     */
+    void deleteByProductId(String productId);
+}

src/main/java/com/example/building/service/impl/CategoryAttributeServiceImpl.java

@@ -0,0 +1,52 @@
+package com.example.building.service.impl;
+
+import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
+import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
+import com.example.building.entity.CategoryAttribute;
+import com.example.building.mapper.CategoryAttributeMapper;
+import com.example.building.service.CategoryAttributeService;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+import java.util.List;
+import java.util.UUID;
+
+/**
+ * 种类属性服务实现
+ */
+@Service
+public class CategoryAttributeServiceImpl implements CategoryAttributeService {
+
+    @Override
+    public List<CategoryAttribute> getByCategoryId(String categoryId) {
+        return this.list(new LambdaQueryWrapper<CategoryAttribute>()
+                .eq(CategoryAttribute::getCategoryId, categoryId)
+                .orderByAsc(CategoryAttribute::getSortOrder));
+    }
+
+    @Override
+    @Transactional
+    public void saveAttributes(String categoryId, List<CategoryAttribute> attrs) {
+        // 删除旧属性
+        this.remove(new LambdaQueryWrapper<CategoryAttribute>()
+                .eq(CategoryAttribute::getCategoryId, categoryId));
+        
+        // 保存新属性
+        if (attrs != null && !attrs.isEmpty()) {
+            for (int i = 0; i < attrs.size(); i++) {
+                CategoryAttribute attr = attrs.get(i);
+                attr.setAttrId(UUID.randomUUID().toString());
+                attr.setCategoryId(categoryId);
+                attr.setSortOrder(i);
+                this.save(attr);
+            }
+        }
+    }
+
+    @Override
+    @Transactional
+    public void deleteByCategoryId(String categoryId) {
+        this.remove(new LambdaQueryWrapper<CategoryAttribute>()
+                .eq(CategoryAttribute::getCategoryId, categoryId));
+    }
+}

src/main/java/com/example/building/service/impl/ProductAttributeServiceImpl.java

@@ -0,0 +1,54 @@
+package com.example.building.service.impl;
+
+import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
+import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
+import com.example.building.entity.ProductAttribute;
+import com.example.building.mapper.ProductAttributeMapper;
+import com.example.building.service.ProductAttributeService;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+import java.util.List;
+import java.util.Map;
+import java.util.UUID;
+
+/**
+ * 商品属性服务实现
+ */
+@Service
+public class ProductAttributeServiceImpl implements ProductAttributeService {
+
+    @Override
+    public List<ProductAttribute> getByProductId(String productId) {
+        return this.list(new LambdaQueryWrapper<ProductAttribute>()
+                .eq(ProductAttribute::getProductId, productId));
+    }
+
+    @Override
+    @Transactional
+    public void saveProductAttributes(String productId, List<Map<String, Object>> attrs) {
+        // 删除旧属性
+        this.remove(new LambdaQueryWrapper<ProductAttribute>()
+                .eq(ProductAttribute::getProductId, productId));
+        
+        // 保存新属性
+        if (attrs != null && !attrs.isEmpty()) {
+            for (Map<String, Object> attr : attrs) {
+                ProductAttribute pa = new ProductAttribute();
+                pa.setId(UUID.randomUUID().toString());
+                pa.setProductId(productId);
+                pa.setAttrId((String) attr.get("attrId"));
+                pa.setAttrName((String) attr.get("attrName"));
+                pa.setAttrValue(String.valueOf(attr.get("attrValue")));
+                this.save(pa);
+            }
+        }
+    }
+
+    @Override
+    @Transactional
+    public void deleteByProductId(String productId) {
+        this.remove(new LambdaQueryWrapper<ProductAttribute>()
+                .eq(ProductAttribute::getProductId, productId));
+    }
+}

src/main/resources/db/migration/V7__add_category_attributes.sql

@@ -0,0 +1,29 @@
+-- 种类属性定义表
+CREATE TABLE IF NOT EXISTS category_attributes (
+    attr_id VARCHAR(36) PRIMARY KEY,
+    category_id VARCHAR(36) NOT NULL,
+    name VARCHAR(50) NOT NULL,
+    attr_type VARCHAR(20) DEFAULT 'number',
+    unit VARCHAR(20),
+    formula VARCHAR(200),
+    sort_order INTEGER DEFAULT 0,
+    required INTEGER DEFAULT 0,
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    FOREIGN KEY (category_id) REFERENCES categories(category_id) ON DELETE CASCADE
+);
+
+-- 商品属性值表
+CREATE TABLE IF NOT EXISTS product_attributes (
+    id VARCHAR(36) PRIMARY KEY,
+    product_id VARCHAR(36) NOT NULL,
+    attr_id VARCHAR(36) NOT NULL,
+    attr_name VARCHAR(50),
+    attr_value VARCHAR(200),
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    FOREIGN KEY (product_id) REFERENCES products(product_id) ON DELETE CASCADE,
+    FOREIGN KEY (attr_id) REFERENCES category_attributes(attr_id) ON DELETE CASCADE
+);
+
+-- 商品表增加默认单位字段
+ALTER TABLE products ADD COLUMN default_unit VARCHAR(20);