使用Mongoose向MongoDB Atlas执行insertMany时遇primitive.D错误

执行Mongoose的insertMany批量插入操作时触发以下错误：

MongoBulkWriteError: Expected 'insert' to be string, but got primitive.D instead.

已尝试在Mongoose连接选项中设置retryWrites: false禁用重试写入，但问题未解决。

相关代码及信息 #

1. Mongoose连接配置 #

// Mongoose connection options
const mongooseOptions = {
   retryWrites: false,
};
mongoose.connect(mongoURI, mongooseOptions);

2. 初始接口代码 #

router.post('/insertMany', async (req, res) => {
    try {
        console.log(req.body);
        const category = await Category.insertMany(req.body.list);
        res.json(category);
    } catch (error) {
        console.log(error);
        res.status(400).json({ error: error.message });
    }
});

3. 修改后的接口代码 #

router.post('/insertMany', async (req, res) => {
    try {
        console.log(req.body);
        let list = req.body.list.map(cat => Category(cat))
        const category = await Category.insertMany(list);
        res.json(category);
    } catch (error) {
        console.log(error);
        res.status(400).json({ error: error.message });
    }
});

4. Postman请求体 #

{
    "list": [
        {
            "name": "Test Category",
            "description": "Test category Desc"
        }
    ]
}

5. 错误日志 #

Incoming POST request to /category/insertMany
{
  list: [ { name: 'Test Category', description: 'Test category Desc' } ]
}
MongoBulkWriteError: Expected 'insert' to be string, but got primitive.D instead. Doc = [{insert [{collection category}]} {documents [[{name Test Category} {active true} {description Test category Desc} {_id ObjectID("65e19ac0e6f006f0730df049")} {__v 0}]]} {ordered true} {writeConcern [{w majority}]} {lsid [{id {4 [20 207 50 38 60 101 78 182 181 103 131 17 48 167 185 124]}}]} {$clusterTime [{clusterTime {1709283559 1}} {signature [{hash {0 [143 10 169 77 44 6 244 27 189 31 40 244 125 245 89 91 153 147 30 152]}} {keyId 7285440633500598274}]}]} {$db desejo}]
    at resultHandler (/Users/jayedumindu/Dev/Desejo-Ecommerce/Backend/node_modules/mongoose/node_modules/mongodb/lib/bulk/common.js:294:29)
    at /Users/jayedumindu/Dev/Desejo-Ecommerce/Backend/node_modules/mongoose/node_modules/mongodb/lib/utils.js:274:66
    at process.processTicksAndRejections (node:internal/process/task_queues:95:5) {
  ok: 0,
  code: 8000,
  codeName: 'AtlasError',
  writeErrors: [],
  result: BulkWriteResult {
    insertedCount: 0,
    matchedCount: 0,
    modifiedCount: 0,
    deletedCount: 0,
    upsertedCount: 0,
    upsertedIds: {},
    insertedIds: { '0': new ObjectId('65e19ac0e6f006f0730df049') }
  },
  insertedDocs: [
    {
      name: 'Test Category',
      active: true,
      description: 'Test category Desc',
      _id: new ObjectId('65e19ac0e6f006f0730df049'),
      __v: 0
    }
  ],
  [Symbol(errorLabels)]: Set(0) {}
}

6. Category模型定义 #

// models/Category.js
const mongoose = require('mongoose');

const categorySchema = new mongoose.Schema({
    name: { type: String, unique: true },
    active: { type: Boolean, default: true }, // Added for tracking the active status
    description: String
});

module.exports = mongoose.model('Category', categorySchema, { collection: 'category' });

错误原因分析 #

错误日志中显示insert字段被传入了嵌套对象[{collection category}]，而MongoDB的批量插入命令要求insert的值是字符串类型的集合名。问题出在Category模型的导出代码：

mongoose.model()的第三个参数如果是对象，会被识别为模型选项，而非集合名。当前代码传入{ collection: 'category' }作为第三个参数，导致Mongoose内部生成批量插入命令时，错误地将集合名处理成了对象结构，最终触发primitive.D类型错误。

解决方法 #

修改Category模型的导出代码，将第三个参数直接传入字符串类型的集合名'category'，而非对象：

// models/Category.js
const mongoose = require('mongoose');

const categorySchema = new mongoose.Schema({
    name: { type: String, unique: true },
    active: { type: Boolean, default: true }, // Added for tracking the active status
    description: String
});

// 第三个参数直接传集合名字符串
module.exports = mongoose.model('Category', categorySchema, 'category');

另外，修改后的接口代码中list = req.body.list.map(cat => Category(cat))这一步是多余的，insertMany可以直接接收普通对象数组，因此可以改回初始的接口代码，也可以保留，不影响功能。

内容的提问来源于stack exchange，提问作者Dumindu Jayasekara