Question

我有一个包含子文档数组的文档：

{
  "company": "test plc",
  "address": [
    {
      "addr1": "37",
      "addr2": "",
      "addr3": "test",
      "addr4": "",
      "addrcity": "",
      "addrcounty": "test",
      "addrpostcode": "test"
    },
    {
      "addr1": "37",
      "addr2": "",
      "addr3": "test",
      "addr4": "",
      "addrcity": "",
      "addrcounty": "test",
      "addrpostcode": "test"
    },
    {
      "addr1": "37",
      "addr2": "",
      "addr3": "test",
      "addr4": "",
      "addrcity": "",
      "addrcounty": "test",
      "addrpostcode": "test"
    }
  ],
  "contacts": [
    {
      "name": "test",
      "surname": "testing",
      "title": "master"
    },
    {
      "name": "test",
      "surname": "testing",
      "title": "master"
    }
  ]
}

我想要做的是通过搜索contacts.surname属性来返回文档列表。

var leads = Lead.find({"contact.surname":req.params.name});

这会导致错误“将循环结构转换为JSON”，但我不确定原因。

在编辑时添加：

这是我的收藏架构：

var leadsSchema = new Schema({
  company: String,
  address:
  [
    {
      addr1: String,
      addr2: String,
      addr3: String,
      addr4: String,
      addrcity: String,
      addrcounty: String,
      addrpostcode: String
    }
  ],
  contacts:
  [
    {
      name: String,
      surname: String,
      title: String
    }
  ]
});
var Lead = mongoose.model('leads', leadsSchema);

这是我的两个路由器：

这将从集合find中返回所有内容：

router.get('/', function(req, res) {
  Lead.find({}).exec(function(err, leads) {
    res.send(leads);
  });
});

这会导致循环错误：

router.get('/findByContactName/:surname', function(req, res) {
  var leads = Lead.find({"contacts.surname":req.params.name});
  res.send(leads);
});

Answer 1

试试这个

router.get('/findByContactName/:surname', function(req, res){
Lead.find({"contacts.surname":req.params.name}).exec(function(err, leads){
res.send(leads);
});

Answer 2

或者尝试这个

 router.get('/findByContactName/:surname', async function(req, res) {
      const leads = await Lead.find({"contacts.surname":req.params.name});
      res.send(leads);
    });

Answer 3

TL; DR：

更改var leads = Lead.find({"contacts.surname":req.params.name});

收件人：

var leads = await Lead.find({"contacts.surname":req.params.name});

说明

model.find（）仅返回查询。它不会为您执行查询。因此，“ leads”变量当前是Mongoose查询文档。

当您进行res.send（leads）时，请在内部进行表达：

JSON.stringify(leads)

stringify（）无法将圆形结构转换为JSON。因此，错误。

如果这里有人可以阐明为什么Mongoose查询文档是圆形结构，那就太好了！

查询Mongodb子文档错误将循环结构转换为JSON

3 个答案: