Error: Converting circular structure to JSON --> starting at object with constructor 'Topology' | property 's' -> object with .... in Nodejs Express

Question

这是我的index.js。我在哪里尝试通过查询字符串搜索功能。我从客户端收到查询，但错误发生在 campground.find() 中，它给出了上述错误

app.get('/results', (req, res) =>{
const {search_query} = req.query
console.log(search_query);
const campgrounds = Campground.find({title: 'gizzly Camp'})
res.send(campgrounds)})

型号：

const ImageSchema = Schema({
url:String,
filename: String,})


const CampgroundSchema = Schema({
title: String,
image: [
    ImageSchema
],
price: Number,
description: String,
category: {
    type: Schema.Types.ObjectId,
    ref: 'Category',
},
location: String,
geometry: {
    type: {
        type: String,
        enum: ['Point'],
        required: true
    },
    coordinates: {
        type: [Number],
        required: true,
    }
},
author:
{
    type: Schema.Types.ObjectId,
    ref: 'User'
},
reviews: [
    {
        type: Schema.Types.ObjectId,
        ref: 'Review'
    }
]}, opts);

这是来自查询的 ejs:

<form action="/results/?" class="d-flex mb-5">
    <input class="form-control me-2" type="search" placeholder="Search Your Campgrounds ...." name="search_query" aria-label="Search">
    <button class="btn btn-outline-dark" type="submit">Search</button>
  </form>

Answer 1

上面的问题解决了我忘了在Campground.find()中写等待，因为它是从数据库中提取数据的异步过程

Error: Converting circular structure to JSON --> starting at object with constructor 'Topology' | property 's' -> object with .... in Nodejs Express

Error: Converting circular structure to JSON --> starting at object with constructor 'Topology' | property 's' -> object with .... in Nodejs Express

structure

circular-dependency

node.js

express