@stephanullmann/mockgoose

A lightweight mock of essential Mongoose features designed specifically for StackBlitz WebContainers.

Why?

Standard MongoDB and Mongoose connections don't work inside browser-based WebContainers. Solutions like mongodb-memory-server require native binaries that are also unsupported in that environment.

mockgoose solves this by mocking the Mongoose API (Schemas, Models, Queries) and persisting data to simple .json files in a local .mockgoose directory.

Features

• Familiar API: Create Schemas and Models just like in Mongoose.
• Persistence: Automatically saves data to .mockgoose/**/*.json sorted by collection.
• WebContainer Compatible: Pure JavaScript/TypeScript, no binaries required.
• Query Support: Supports common operations like find, findOne, create, updateOne, deleteOne, etc.

Installation

npm install @stephanullmann/mockgoose

Basic Usage

import { connect, Schema, model } from '@stephanullmann/mockgoose';

await connect('mongodb://localhost:27017/myapp'); // The URI is ignored, but setup is performed

//  Define a Schema
const userSchema = new Schema({
  name: String,
  email: { type: String, required: true },
  age: Number
});

//  Create a Model
const User = model('User', userSchema);

//  Use it like Mongoose
async function run() {
  // Create
  const newUser = await User.create({ 
    name: 'Guybrush Threeepwood', 
    email: '[email protected]', 
    age: 24 
  });

  // Read
  const users = await User.find({ age: { $gte: 18 } });
  
  // Update
  await User.updateOne({ _id: newUser._id }, { age: 31 });

  // Delete
  await User.deleteOne({ _id: newUser._id });
}

Supported Features

mockgoose aims to support the most common Mongoose operations, but it is not a 1:1 replacement.

Current Limitations:

• Schema Validation: Basic schema structure is supported, but strict validation (required, min/max, custom validators) is not yet implemented.
• Typescript: Basic type inference is available, but complex Mongoose Document types are not supported.
• Advanced Queries: Features like Aggregation Pipelines, and complex populate calls are currently not supported or have limited support.
• Connection: connect() is present for API compatibility but ignores the connection string.

Storage

Data is stored in the root of your project:

.mockgoose/
  ├── Users.json
  └── Books.json