> [Wiki](Home) ▸ [[API Reference|API-Reference]] ▸ **Schema**
# Schema
Module used to validate structures.
Access it with:
```javascript
const { Schema } = Neft;
```
> [`Source`](/Neft-io/neft/blob/8a7d1218650a3ad43d88cdbda24dae5a72a732ea/src/schema/index.litcoffee)
## Nested APIs
* [[Array Validator|Schema-Array Validator-API]]
* [[Max Validator|Schema-Max Validator-API]]
* [[Min Validator|Schema-Min Validator-API]]
* [[Object Validator|Schema-Object Validator-API]]
* [[Optional Validator|Schema-Optional Validator-API]]
* [[Options Validator|Schema-Options Validator-API]]
* [[RegExp Validator|Schema-RegExp Validator-API]]
* [[Type Validator|Schema-Type Validator-API]]
## Table of contents
* [Schema](#schema)
* [**Class** SchemaError](#class-schemaerror)
* [**Class** Schema](#class-schema)
* [constructor](#constructor)
* [schema](#schema)
* [validate](#validate)
* [Nested properties](#nested-properties)
##**Class** SchemaError
- Syntax
**Class** SchemaError()
Raised by `Schema::validate()` if given data doesn't pass the schema.
Access it with:
```javascript
var Schema = require('schema');
var SchemaError = Schema.Error;
```
> [`Source`](/Neft-io/neft/blob/8a7d1218650a3ad43d88cdbda24dae5a72a732ea/src/schema/index.litcoffee#class-schemaerror)
## **Class** Schema
> [`Source`](/Neft-io/neft/blob/8a7d1218650a3ad43d88cdbda24dae5a72a732ea/src/schema/index.litcoffee)
###constructor
- Syntax
Schema::constructor(*Object* schema)- Prototype method of
- Schema
- Parameters
Creates a new Schema instance used to validate data.
Specify schema validators for each of the accepted property.
```javascript
new Schema({
address: {
type: 'string'
},
delivery: {
optional: true,
type: 'boolean'
}
});
```
> [`Source`](/Neft-io/neft/blob/8a7d1218650a3ad43d88cdbda24dae5a72a732ea/src/schema/index.litcoffee#schemaconstructorobject-schema)
###schema
- Syntax
*Object* Schema::schema- Prototype property of
- Schema
- Type
- Object
Saved schema object from the constructor.
It's allowed to change this object in runtime.
> [`Source`](/Neft-io/neft/blob/8a7d1218650a3ad43d88cdbda24dae5a72a732ea/src/schema/index.litcoffee#object-schemaschema)
###validate
- Syntax
*Boolean* Schema::validate(*Object* data)- Prototype method of
- Schema
- Parameters
- Returns
- Boolean
Validates the given data object by the schema.
Returns `true` if the data is valid, otherwise throws an SchemaError instance.
```javascript
var schema = new Schema({
age: {
type: 'number',
min: 0,
max: 200
}
});
console.log(utils.catchError(schema.validate, schema, [{}])+'');
// "SchemaError: Required property age not found"
console.log(utils.catchError(schema.validate, schema, [{name: 'Jony'}])+'');
// "SchemaError: Unexpected name property"
console.log(utils.catchError(schema.validate, schema, [{age: -5}])+'');
// "SchemaError: Minimum range of age is 0"
console.log(schema.validate({age: 20}));
// true
console.log(utils.tryFunction(schema.validate, schema, [{age: -1}], false));
// false
console.log(utils.tryFunction(schema.validate, schema, [{age: 5}], false));
// true
```
#### Nested properties
Use dot in the property name to valdiate deep objects.
```javascript
var schema = new Schema({
obj: {
type: 'object'
},
'obj.prop1.name': {
type: 'string'
}
});
console.log(utils.catchError(schema.validate, schema, [{obj: {prop1: {name: 123}}}])+'');
// "SchemaError: obj.prop1.name must be a string"
console.log(schema.validate({obj: {prop1: {name: 'Lily'}}}));
// true
```
This function uses *utils.get()* internally.
```javascript
var schema = new Schema({
names: {
array: true
},
'names[]': {
type: 'string'
}
});
console.log(utils.catchError(schema.validate, schema, [{names: [123, null]}])+'');
// "SchemaError: names[] must be a string"
console.log(schema.validate({names: ['Lily', 'Max']}));
// true
```
> [`Source`](/Neft-io/neft/blob/8a7d1218650a3ad43d88cdbda24dae5a72a732ea/src/schema/index.litcoffee)