The Problem

You love Mongoose for all it's convenience methods and valiate-before-saving logic, but but you store complex objects using Schema.Types.Mixed which lacks validation in Mongoose, or you just wish you could validate objects, strings, etc. using a richer JSON-schema vocabulary than is included with Mongoose.

The Solution

The mongoose-ajv-plugin lets you use the awesome AJV JSON-Schema validation library, to validate individual attributes or entire documents, giving you access to it's rich extensible schema vocabulary and convenience formats like email, Date, hostname, ect.

Getting Started

Import mongoose and add in the mongoose-ajv-plugin:

var mongoose = require("mongoose");
mongoose.plugin(require("mongoose-ajv-plugin"))

Now use your favorite AJV Schema, such as the ajv_contact_schema defined below, to validate entire documents using the "ajv-schema" keyword, like so:

var Contact_schema = new mongoose.Schema({
    "name": String ,
    "email": String,
    "birthday": String,
    // let AJV validate this entire document
    "ajv-schema": ajv_contact_schema 
});

Or use AJV to validate one or more attributes of a document using the "ajv-schema" option:

// use AJV to validate fields within a document
var Player_schema = new Schema({
    "user_name": String,
    "rank": Number,
    "ip_address": { 
        "type": String, 
        // let AJV validate this string attribute
        "ajv-schema": { 
            "type": 'string',
            "format": 'ipv4'  /
        } 
    },
    "contact-info": {
        "type": Schema.Types.Mixed ,
        // let AJV validate this nested object
        "ajv-schema": contact_json_schema 
    },
});

Using AJV Extensions

If you wish to extend the Ajv instance used for validation with additional schemata, formats, or keywords, you can pass your own (extended) ajv instance to the plugin, like so:

// create an Ajv instance
var Ajv = require("ajv");
var ajv = new Ajv();

// add custom schema, keywords, or formats
ajv.addSchema(...);
// or 
ajv.addKewword(...)
// or 
ajv.addFormat(...)
// or 
require("my-ajv-plugin")(ajv)

// use this ajv instance to compile every new validator
mongoose.plugin(require("mongoose-ajv-plugin",{"ajv":ajv})

// or use this ajv instance to compile validators for an individual
// mongoose schema
var my_schema = new mongoose.Schema({...});
my_schema.plugin(require("mongoose-ajv-plugin",{"ajv":ajv})

Contact JSON schema

And finally, here's the definition of ajv_contact_schema used in the above examples:

var ajv_contact_schema = {
    "type":"object",
    "properties":{
        "name": {
            "type":"string"
        },
        "email": {
            "type":"string",
            "fomrat":"email"
        },
        "birthday": {
            "oneOf":[
                {"$ref":"#/definitions/date"},
                {"$ref":"#/definitions/date-time"}
            ]
        }
    },
    "required":[
        "name",
        "email"
    ],
    "definitions":{
        "date":{
            "type":"string",
            "format":"date"
        },
        "date-time":{
            "type":"string",
            "format":"date-time"
        }
    }
};