Generate mongoose schema for your MongoDB database model from dynamic JSON objects with mixed types

gistfile1.txt

const mongoose = require('mongoose');

// Example JSON object with mixed types in arrays
const json = {
    "name": "John Doe",
    "age": 30,
    "email": "[email protected]",
    "isActive": true,
    "roles": [
        {"role": "admin", "level": 1},
        {"role": "user", "access": ["read", "write"]}
    ],
    "history": [
        {"event": "login", "timestamp": "2024-08-10T12:00:00Z"},
        {"event": "purchase", "item": "laptop", "price": 1200}
    ]
};

// Function to generate Mongoose schema from JSON
function generateSchemaFromJson(json) {
    const schemaDefinition = {};

    for (const key in json) {
        const value = json[key];

        if (Array.isArray(value)) {
            if (typeof value[0] === 'object' && value[0] !== null) {
                // If the array contains objects, use Mixed type
                schemaDefinition[key] = [mongoose.Schema.Types.Mixed];
            } else {
                // If the array contains primitive types
                schemaDefinition[key] = [getType(value[0])];
            }
        } else if (typeof value === 'object' && value !== null) {
            // Handle nested objects
            schemaDefinition[key] = generateSchemaFromJson(value);
        } else {
            // Handle primitive types
            schemaDefinition[key] = getType(value);
        }
    }

    return new mongoose.Schema(schemaDefinition);
}

// Helper function to determine the type
function getType(value) {
    if (typeof value === 'string') {
        return String;
    } else if (typeof value === 'number') {
        return Number;
    } else if (typeof value === 'boolean') {
        return Boolean;
    } else if (value instanceof Date || !isNaN(Date.parse(value))) {
        return Date;
    } else if (typeof value === 'object') {
        return mongoose.Schema.Types.Mixed; // Use Mixed type for complex objects
    } else {
        throw new Error(`Unknown type for value: ${value}`);
    }
}

// Generate the Mongoose schema
const dynamicSchema = generateSchemaFromJson(json);

// Create a Mongoose model
const DynamicModel = mongoose.model('DynamicModel', dynamicSchema);

// Example usage: Create and save a new document
const newDocument = new DynamicModel(json);

newDocument.save()
    .then(doc => {
        console.log('Document saved:', doc);
    })
    .catch(err => {
        console.error('Error saving document:', err);
    });