mongoose-graphql-codegen

Generate GraphQL schema and resolvers automatically from Mongoose models — supports BSON types and advanced validation.

✨ Features

• Generates .graphql type definitions
• Creates resolvers with status code-aware GraphQL errors
• Supports both JavaScript (CommonJS) and TypeScript
• Handles BSON/extended scalar types: Decimal, Long, Date, UUID, Base64, etc.

📦 Installation

Install via npm

npm install -D mongoose-graphql-codegen

🧠 Example Mongoose Model

// models/User.js
const mongoose = require('mongoose');
const bcrypt = require('bcrypt');

const userSchema = new mongoose.Schema({
  name: { type: String, required: true },
  email: { type: String, required: true, unique: true },
  password: { type: String, required: true, minlength: 6 },
  roles: {
    type: [String],
    enum: ['user', 'admin', 'moderator'],
    default: ['user']
  },
  status: {
    type: String,
    enum: ['active', 'inactive', 'banned'],
    default: 'active'
  },
  lastLogin: Date
});

userSchema.pre('save', async function (next) {
  if (!this.isModified('password')) return next();
  const salt = await bcrypt.genSalt(10);
  this.password = await bcrypt.hash(this.password, salt);
  next();
});

userSchema.methods.comparePassword = async function (candidatePassword) {
  return bcrypt.compare(candidatePassword, this.password);
};

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

⚙️ Usage

TypeScript Generate for all models in the models directory

npx mongoose-graphql-codegen

Javascript Generate for all models in the models directory

npx mongoose-graphql-codegen js=true

JavaScript (CommonJS) graphql-codegen generate for a single Mongoose model

npx mongoose-graphql-codegen model=./models/User.js js=true

📁 Output Structure

After generation:

graphql-codegen/
  user/
    User.graphql
    UserResolver.js / .ts
  index.ts
  scalarResolvers.js / .ts

🛠 Integrate into Apollo GraphQL Server

//<filename>.js
const { ApolloServer } = require('@apollo/server');
const {typeDefs,resolvers} = require('../graphql-codegen')

async function createApolloServer() {
  const server = new ApolloServer({
    typeDefs,
    resolvers
  });
  await server.start();
  return server;
}

module.exports = createApolloServer;

// server.js
const bodyParser = require('body-parser');
const { expressMiddleware } = require('@apollo/server/express4');
const createApolloServer = require('./graphql/server');
(async () => {
const apolloServer = await createApolloServer();
app.use('/graphql', bodyParser.json(), expressMiddleware(apolloServer));
})();

// Use in ApolloServer, Mercurius, Yoga, etc.

📌 Coming Soon

• --outDir support

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