zod-mongoose-bridge

A simple, lightweight utility to automatically generate Mongoose Schema definitions from Zod validation schemas. This eliminates the duplicate effort of writing separate schemas for data validation (Zod) and database models (Mongoose).

Features

• 🚀 Dynamic Translation — translates Zod types (ZodString, ZodNumber, ZodBoolean, ZodDate, ZodEnum, ZodArray, ZodObject) to their Mongoose equivalents.
• 🔒 Validation Sync — converts Zod enums into Mongoose validation enums automatically.
• ⚙️ Required Sync — handles .optional() and .nullable() constraints, mapping them to Mongoose required: false vs required: true.
• 📦 Nested Object Support — recursively resolves nested objects and arrays of nested objects.

Installation

npm install zod-mongoose-bridge

Note: zod and mongoose are required as peer dependencies.

Usage

const mongoose = require('mongoose');
const { z } = require('zod');
const { convertZodToMongoose } = require('zod-mongoose-bridge');

// 1. Define your validation schema with Zod
const UserValidationSchema = z.object({
  username: z.string(),
  email: z.string(),
  age: z.number().optional(),
  role: z.enum(['admin', 'user', 'guest']),
  tags: z.array(z.string()),
  address: z.object({
    city: z.string(),
    zipCode: z.string().optional()
  })
});

// 2. Generate Mongoose schema definition
const mongooseDefinition = convertZodToMongoose(UserValidationSchema);

// 3. Create your Mongoose Model
const UserSchema = new mongoose.Schema(mongooseDefinition, { timestamps: true });
const UserModel = mongoose.model('User', UserSchema);

Generated Schema Mapping Reference

The conversion performs the following mappings:

| Zod Type | Mongoose Type | Required State | |---|---|---| | z.string() | String | required: true (default) | | z.string().optional() | String | required: false | | z.number() | Number | required: true | | z.boolean() | Boolean | required: true | | z.date() | Date | required: true | | z.enum(['a', 'b']) | String with enum: ['a', 'b'] | required: true | | z.array(z.string()) | [String] | required: false | | z.object({...}) | Nested object schema {...} | Checked properties |

Options

convertZodToMongoose(zodSchema, options) accepts:

const definition = convertZodToMongoose(UserValidationSchema, {
  defaultRequired: false // If false, fields will not be marked 'required: true' unless explicitly validated (default: true)
});

License

MIT