Postman向MongoDB提交数据遇ObjectId转换错误求助

使用Postman通过http://localhost:5000/api/import/products接口提交产品数据时触发ValidationError，错误信息如下：

{
    "message": "Product validation failed: _id: Cast to ObjectId failed for value \"1\" (type string) at path \"_id\"",
    "stack": "ValidationError: Product validation failed: _id: Cast to ObjectId failed for value \"1\" (type string) at path \"_id\"\n    at model.Document.invalidate (D:\\Uni\\SE_Y3\\Semester 1\\Web Programming\\Project code\\Uptown_Book\\server\\node_modules\\mongoose\\lib\\document.js:2917:32)\n    at model.$set (D:\\Uni\\SE_Y3\\Semester 1\\Web Programming\\Project code\\Uptown_Book\\server\\node_modules\\mongoose\\lib\\document.js:1454:12)\n    at model.$set (D:\\Uni\\SE_Y3\\Semester 1\\Web Programming\\Project code\\Uptown_Book\\server\\node_modules\\mongoose\\lib\\document.js:1149:16)\n    at model.Document (D:\\Uni\\SE_Y3\\Semester 1\\Web Programming\\Project code\\Uptown_Book\\server\\node_modules\\mongoose\\lib\\document.js:158:12)\n    at model.Model (D:\\Uni\\SE_Y3\\Semester 1\\Web Programming\\Project code\\Uptown_Book\\server\\node_modules\\mongoose\\lib\\model.js:107:12)\n    at new model (D:\\Uni\\SE_Y3\\Semester 1\\Web Programming\\Project code\\Uptown_Book\\server\\node_modules\\mongoose\\lib\\model.js:4792:15)\n    at Array.<anonymous> (D:\\Uni\\SE_Y3\\Semester 1\\Web Programming\\Project code\\Uptown_Book\\server\\node_modules\\mongoose\\lib\\model.js:3336:17)\n    at _start (D:\\Uni\\SE_Y3\\Semester 1\\Web Programming\\Project code\\Uptown_Book\\server\\node_modules\\mongoose\\lib\\helpers\\parallelLimit.js:27:37)\n    at parallelLimit (D:\\Uni\\SE_Y3\\Semester 1\\Web Programming\\Project code\\Uptown_Book\\server\\node_modules\\mongoose\\lib\\helpers\\parallelLimit.js:23:5)\n    at Function.Model.$__insertMany (D:\\Uni\\SE_Y3\\Semester 1\\Web Programming\\Project code\\Uptown_Book\\server\\node_modules\\mongoose\\lib\\model.js:3366:3)"
}

提交的产品数据：

const products = [
  {
    _id: "1",
    name: "Velcro Ballerinas For Girls  (Pink)",
    image: "/images/6.png",
    description: "Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book",
    price: 89,
    countInStock: 3,
    rating: 4,
    numReviews: 4,
  },
  {
    _id: "2",
    name: "Velcro Sneakers For Boys & Girls  (Blue)",
    image: "/images/5.png",
    description: "Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book",
    price: 599,
    countInStock: 10,
    rating: 2,
    numReviews: 2,
  },
  {
    _id: "3",
    name: "Sesame Street Unisex-Child ELMO Puppet Slipper",
    image: "/images/4.png",
    description: "Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book",
    price: 929,
    countInStock: 0,
    rating: 3.5,
    numReviews: 3,
  },
  {
    _id: "4",
    name: "Lace Casual Boots For Boys & Girls  (Tan)",
    image: "/images/3.png",
    description: "Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book",
    price: 399,
    countInStock: 10,
    rating: 5,
    numReviews: 9,
  },
  {
    _id: "5",
    name: "Lace Walking Shoes For Boys & Girls  (Pink)",
    image: "/images/2.png",
    description: "Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book",
    price: 49,
    countInStock: 7,
    rating: 2,
    numReviews: 2,
  },
  {
    _id: "6",
    name: "Women Red Heels Sandal",
    image: "/images/1.png",
    description: "Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book",
    price: 29,
    countInStock: 0,
    rating: 0,
    numReviews: 0,
  },
];

export default products;

修复方案 #

方案1：移除自定义_id，让Mongo自动生成 #

Mongoose默认会为每个文档自动生成符合ObjectId格式的_id，无需手动指定数值型字符串的_id。修改产品数据，删除所有_id字段即可：

const products = [
  {
    name: "Velcro Ballerinas For Girls  (Pink)",
    image: "/images/6.png",
    description: "Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book",
    price: 89,
    countInStock: 3,
    rating: 4,
    numReviews: 4,
  },
  // 其他产品同理，删除_id字段
];

方案2：修改Schema，允许自定义字符串类型的_id #

如果必须使用自定义的_id（如数值字符串"1"、"2"），需在Mongoose的Product Schema中显式指定_id类型为String，而非默认的ObjectId：

const productSchema = new mongoose.Schema({
  _id: { type: String, required: true }, // 指定类型为String
  name: { type: String, required: true },
  image: { type: String, required: true },
  description: { type: String, required: true },
  price: { type: Number, required: true },
  countInStock: { type: Number, required: true },
  rating: { type: Number, required: true },
  numReviews: { type: Number, required: true },
});

const Product = mongoose.model('Product', productSchema);

修改Schema后重启服务，再提交原数据即可通过验证。

方案3：将_id转换为ObjectId格式（不推荐，除非有特殊需求） #

若坚持使用ObjectId类型的_id，需把每个产品的_id改成MongoDB认可的24位十六进制ObjectId字符串，例如：

const products = [
  {
    _id: "60d21b4667d0d8992e610c85", // 合法的ObjectId
    // 其他字段不变
  },
];

此方式需手动生成合法的ObjectId，一般不建议，除非有特定关联需求。

内容的提问来源于stack exchange，提问作者Shiraie