Database query within static function causes the program to wait indefinitely.

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英文:

Database query within static function causes the program to wait indefinitely

问题

I'm following a youtube tutorial (https://www.youtube.com/watch?v=mjZIv4ey0ps&list=PL4cUxeGkcC9g8OhpOZxNdhXggFz2lOuCT&index=3&t=597s) for making a login and authorization system and provided the link for the part I'm stuck on. you see when I invoke this.findOne({}) function from within a static method I created in the Schema file, the program starts waiting indefinitely, and no further code runs. The code for the model is,

const mongoose = require('mongoose')
const Schema = mongoose.Schema
const bcrypt = require('bcrypt')

const userSchema = new Schema({
    email: {
        type: String,
        required: true,
        unique: true,
    },
    password: {
        type: String,
        required: true
    }
})
userSchema.statics.signup = async (email, password) => {
    console.log("Static Method Triggered")
    const exists = await this.findOne({ email })
    console.log("Verifying existence")

    if (exists) {
        throw Error("Email is already in use")
    }
    console.log("Existence verified")

    const salt = await bcrypt.genSalt(5)
    const hash = await bcrypt.hash(password, salt)
    console.log(hash)
    const user = await this.create({ email: email, password: hash })
    console.log("End of function")
    return user
}

module.exports = mongoose.model('User', userSchema)

As you can see, I have log statements to see how far the program gets. I get the "Static Method Triggered" statement in the console, but not the "Verifying existence" statement or any subsequent statements. This means that the program is waiting indefinitely at the const exists = await this.fineOne({email}) line.

I have tried using find instead of findOne, same result. Other queries to the database work, so it's not a problem with MongoDB Atlas. Only custom functions (static methods) are having this problem. I tried editing the statement to

findOne({email: email})

and it's still the same result. Removing these statements entirely causes the salt and hash statements to run, and the hash to be logged, but then the program starts to wait indefinitely again at the

const user = await this.create({email: email, password: hash})

line. If I do console.log(this), it returns empty curly brackets {}. What am I doing wrong? Did I miss a step somewhere in the tutorial?

英文:

I'm following a youtube tutorial (https://www.youtube.com/watch?v=mjZIv4ey0ps&list=PL4cUxeGkcC9g8OhpOZxNdhXggFz2lOuCT&index=3&t=597s) for making a login and authorization system and provided the link for the part I'm stuck on. you see when I invoke this.findOne({}) function from within a static method I created in the Schema file, the program starts waiting indefinitely, and no further code runs. The code for the model is,

const mongoose = require('mongoose')
const Schema = mongoose.Schema
const bcrypt = require('bcrypt')

const userSchema = new Schema({
    email: {
        type: String,
        required: true,
        unique: true,
    },
    password: {
        type: String,
        required: true
    }
})
userSchema.statics.signup = async (email, password) => {
    console.log("Static Method Triggered")
    const exists = await this.findOne({ email })
    console.log("Verifying existence")

    if (exists) {
        throw Error("Email is already in use")
    }
    console.log("Existence verified")

    const salt = await bcrypt.genSalt(5)
    const hash = await bcrypt.hash(password, salt)
    console.log(hash)
    const user = await this.create({ email: email, password: hash })
    console.log("End of function")
    return user
}

module.exports = mongoose.model('User', userSchema) 

As you can see, I have log statements to see how far the program gets. I get the "Static Method Triggered" statement in the console, but not the "Verifying existence" statement or any subsequent statements. This means that the program is waiting indefinitely at the const exists = await this.fineOne({email}) line.

I have tried using find instead of findOne, same result. Other queries to the database work so it's not a problem with mongodb Atlas. Only custom functions (static methods) are having this problem. I tried editing the statement to

findOne({email: email})

and it's still the same result. Removing these statements entirely causes the salt and hash statements to run and the hash to be logged, but then the program starts to wait indefinitely again at the

const user = await this.create({email: email, password: hash})

line. If I do console.log(this), it returns empty curly brackets {}. What am I doing wrong? Did I miss a step somewhere in the tutorial?

答案1

得分: 1

The this keyword works differently in arrow functions () => {}. 所以请使用普通函数 function(){} 代替。

更新的代码:

userSchema.statics.signup = async function(email, password) {
    console.log("Static Method Triggered")
    const exists = await this.findOne({ email })
    console.log("Verifying existence")

    if (exists) {
        throw Error("Email is already in use")
    }
    console.log("Existence verified")

    const salt = await bcrypt.genSalt(5)
    const hash = await bcrypt.hash(password, salt)
    console.log(hash)
    const user = await this.create({ email: email, password: hash })
    console.log("End of function")
    return user
}

希望这有所帮助。

英文:

The this keyword works different in arrow functions () => {}. So use a regular function function(){} instead.

Updated code:

userSchema.statics.signup = async function(email, password) {
    console.log("Static Method Triggered")
    const exists = await this.findOne({ email })
    console.log("Verifying existence")

    if (exists) {
        throw Error("Email is already in use")
    }
    console.log("Existence verified")

    const salt = await bcrypt.genSalt(5)
    const hash = await bcrypt.hash(password, salt)
    console.log(hash)
    const user = await this.create({ email: email, password: hash })
    console.log("End of function")
    return user
}

Hope this helps

huangapple
  • 本文由 发表于 2023年6月30日 00:19:42
  • 转载请务必保留本文链接:https://go.coder-hub.com/76582894.html
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