Mongoose Integration (in progress)

ds-express-errors can automatically identify and map Mongoose errors into appropriate HTTP errors and responses.

The Mongoose mapper works out of the box and does not require any additional configuration.

1. Basic integration
2. Supported errors
3. Configuration
4. Strict error detection
5. Example
6. Resulting responses

1. Basic Integration

Use Mongoose normally in your application and add the ds-express-errors error handler after all routes.

Add errorHandler after your application routes:

javascript

Import syntaxES Modules (import)CommonJS (require) Copy

import express from 'express'
import { errorHandler } from 'ds-express-errors'

const app = express();

// Your routes

// Add Error Handler at the very end
app.use(errorHandler);

If Mongoose throws a supported error, it will be automatically identified and mapped by errorHandler.

2. Supported Errors

The Mongoose mapper handles the following errors:

3. Configuration

By default, all available mappers are enabled.

If you want ds-express-errors to use only selected mappers, configure them with needMappers:

javascript

Import syntaxES Modules (import)CommonJS (require) Copy

import { setConfig } from 'ds-express-errors'

setConfig({ needMappers: ['mongoose'] })

4. Strict Error Detection

Strict error detection through errorClasses is currently not available for Mongoose.

Mongoose errors are identified using the library's default zero-dependency detection.

No Mongoose package or error classes need to be passed to ds-express-errors.

5. Example

Consider a Mongoose schema with a unique email and validation rules:

javascript

Copy

const userSchema = new mongoose.Schema({ 
  email: { 
    type: String, 
    required: [true, 'Email is required'], 
    unique: true 
  }, 
  age: { 
    type: Number, 
    min: [18, 'Age must be at least 18'] 
  } 
}) 
const User = mongoose.model('User', userSchema)

If an operation attempts to create a user with an email that already exists:

javascript

Copy

await User.create({ email: 'user@example.com', age: 25 })

MongoDB can throw a duplicate key error with code 11000.

ds-express-errors identifies it and maps it to 409 Conflict.

The same applies to Mongoose validation and cast errors without requiring manual checks for each error type.

6. Resulting Responses

For a supported Mongoose error, the final response follows the standard ds-express-errors response format. (configured by setConfig())

For example, a Duplicate key error in production is mapped to:

json

Copy

{ 
	"status": "fail", 
	"message": "Duplicate field value entered" 
}