ADD file via upload

User.js

@@ -0,0 +1,44 @@
+const mongoose = require('mongoose');
+const bcrypt = require('bcryptjs');
+
+const userSchema = new mongoose.Schema({
+    username: {
+        type: String,
+        required: true,
+        unique: true,
+        trim: true
+    },
+    password: {
+        type: String,
+        required: true
+    },
+    role: {
+        type: String,
+        enum: ['student', 'teacher', 'admin'],
+        default: 'student'
+    },
+    createdAt: {
+        type: Date,
+        default: Date.now
+    }
+});
+
+// 密码加密中间件
+userSchema.pre('save', async function (next) {
+    if (!this.isModified('password')) return next();
+
+    try {
+        const salt = await bcrypt.genSalt(10);
+        this.password = await bcrypt.hash(this.password, salt);
+        next();
+    } catch (err) {
+        next(err);
+    }
+});
+
+// 密码验证方法
+userSchema.methods.comparePassword = async function (candidatePassword) {
+    return await bcrypt.compare(candidatePassword, this.password);
+};
+
+module.exports = mongoose.model('User', userSchema);