Validation

Required

const courseSchema = new Mongoose.Schema({
  name:{type:String, required:true},	//to valide that name must not be empty
});
const createCourse = async() =>{
  const course = new Course({
    //name:"NodeJS Intro",
  });
  try{
    const result = await course.save();
    console.log(result);		
  }catch(error){
    console.log(error);	//Will generate an error when validation fails
  }
}

minLength maxLength

const courseSchema = new Mongoose.Schema({
  name:{type:String,required:true,minlength:5,maxlength:255},		//min and max of text
});

min max

const courseSchema = new Mongoose.Schema({
  price:{type:Number,required:true,min:0,max:9999},			//min and max of numbers
  date:{type:Date,min:'1900-01-01',max:'9999-12-31'}			//min and max of dates
});

enum

const courseSchema = new Mongoose.Schema({
  type:{type:String,enum:['physical','audiobook','ebook','pdf']},			//restrict entry
});

round

const courseSchema = new Mongoose.Schema({
  price:{
    type:Number,
    set:v => Math.round(v),			//when setting into database, round to the nearest whole number
    get:v => Math.round(v)			//when getting from database, round to the nearest whole number
  }	
});

lowercase uppercase

const courseSchema = new Mongoose.Schema({
  name:{type:String,lowercase:true},		//convert to lowercase
  author:{type:String,upppercase:true},		//convert to uppercase
});

trim

const courseSchema = new Mongoose.Schema({
  description:{type:String,trim:true}		//trim left and right blank spaces
});

default

const courseSchema = new Mongoose.Schema({
  isPublished:{type:Boolean,default:false},		//set default value
  date:{type:Date,default:Date.now}
});

match

• match is used to set a regexp validator for your schema value

const courseSchema = new Mongoose.Schema({
  email:{type:String,match:/.+@[^@]+\.[^@]{2,}$/}
});

custom

• we can set our own validator

const courseSchema = new Mongoose.Schema({
  tag:{
    type:Array,
    validate:{validator:function(v){return v && v.length>0;},message:'a course should have a least one tag'}
  }
});