Question

在我的项目中，我使用猫鼬，并且我想使用select查询从JSON文件中选择特定字段。猫鼬的文档说正确的形式是这样的：

// selecting the `name` and `occupation` fields
query.select('name occupation');

过滤时，我用,分隔字段，但用（space）

替换了它们

这是我的代码段：

//@desc     Get all bootcamps
//@route    GET /api/v1/bootcamps
//@access   Public

exports.getBootcamps = async (req, res, next) => {
    try {
        let query;

        //Copy req.query
        const reqQuery = { ...req.query };

        //Fields to exclude
        const removeFields = ['select'];

        //Loop over the removeFields and delete them from reqQuery
        removeFields.forEach(param => delete reqQuery[param]);

        //Create query string
        let queryStr = JSON.stringify(req.query);

        //Create operators($gt, $gte, etc)
        const regex = /\b(gt|gte|lt|lte|in)\b/g;
        queryStr = queryStr.replace(regex, match => `$${match}`);

        //Finding resouce
        query = Bootcamp.find(JSON.parse(queryStr));

        //Select Fields

        if (req.query.select) {
            const fields = req.query.select.split(',').join(' ');
            console.log(fields);
            query = query.select(fields);
        }

        //Executing query
        const bootcamps = await query;

        res.status(200).json({
            succes: true,
            count: bootcamps.length,
            data: bootcamps
        });
    } catch (err) {
        return res.status(404).json({ succes: false });
    }
};

因此，console.log(fields);之后，我得到了正确的形式，即：name description，因为在URL中过滤器是

{{URL}}?select=name,description

但是在将其传递给query = query.select(fields);之后，我得到了一个200响应的空数组...

我的JSON文件：

{
        "_id": "5d713995b721c3bb38c1f5d0",
        "name": "Devworks Bootcamp",
        "description": "Devworks is a full stack JavaScript Bootcamp located in the heart of Boston that focuses on the technologies you need to get a high paying job as a web developer",
        "website": "https://devworks.com",
        "phone": "(111) 111-1111",
        "email": "enroll@devworks.com",
        "address": "233 Bay State Rd Boston MA 02215",
        "careers": ["Web Development", "UI/UX", "Business"],
        "housing": true,
        "jobAssistance": true,
        "jobGuarantee": false,
        "acceptGi": true
    }

编辑：我试图这样写查询：

const bootcamps = await query.select('name description');

当然这次没有使用过滤和 IT WORKED 。我现在不明白...我得到了想要的东西

{
    "succes": true,
    "count": 4,
    "data": [
        {
            "_id": "5d713a66ec8f2b88b8f830b8",
            "name": "ModernTech Bootcamp",
            "description": "ModernTech has one goal, and that is to make you a rockstar developer and/or designer with a six figure salary. We teach both development and UI/UX"
        },
        {
            "_id": "5d725a1b7b292f5f8ceff788",
            "name": "Devcentral Bootcamp",
            "description": "Is coding your passion? Codemasters will give you the skills and the tools to become the best developer possible. We specialize in front end and full stack web development"
        },
        {
            "_id": "5d713995b721c3bb38c1f5d0",
            "name": "Devworks Bootcamp",
            "description": "Devworks is a full stack JavaScript Bootcamp located in the heart of Boston that focuses on the technologies you need to get a high paying job as a web developer"
        },
        {
            "_id": "5d725a037b292f5f8ceff787",
            "name": "Codemasters",
            "description": "Is coding your passion? Codemasters will give you the skills and the tools to become the best developer possible. We specialize in full stack web development and data science"
        }
    ]
}

NodeJS，猫鼬：选择查询无效

0 个答案: