$jsonSchema

On this page

Definition

Syntax
JSON Schema
Examples

Definition

$jsonSchema: The $jsonSchema operator matches documents that satisfy the specified JSON Schema.

Syntax

The $jsonSchema operator expression has the following syntax:

{ $jsonSchema: <JSON Schema object> }

Where the JSON Schema object is formatted according to draft 4 of the JSON Schema standard.

{ <keyword1>: <value1>, ... }

For example:

{
  $jsonSchema: {
     required: [ "name", "major", "gpa", "address" ],
     properties: {
        name: {
           bsonType: "string",
           description: "must be a string and is required"
        },
        address: {
           bsonType: "object",
           required: [ "zipcode" ],
           properties: {
               "street": { bsonType: "string" },
               "zipcode": { bsonType: "string" }
           }
        }
     }
  }
}

JSON Schema

MongoDB supports draft 4 of JSON Schema, including core specification and validation specification, with some differences. For details, see Extensions and Omissions.

For more information about JSON Schema, see the official website.

Available Keywords

You can specify the following keywords in your JSON Schema.

Note

MongoDB implements a subset of keywords available in JSON Schema. For a complete list of omissions, see Omissions.

Keyword	Type	Definition	Behavior
additionalItems	arrays	boolean or object	If an object, must be a valid JSON Schema
additionalProperties	objects	boolean or object	If `true`, additional fields are allowed. If `false`, they are not. If a valid JSON Schema object is specified, additional fields must validate against the schema. Defaults to `true`.
allOf	all types	array of JSON Schema objects	Field must match all specified schemas
anyOf	all types	array of JSON Schema objects	Field must match at least one of the specified schemas
bsonType	all types	string alias or array of string aliases	Accepts same string aliases used for the `$type` operator
dependencies	objects	object	Describes field or schema dependencies
description	N/A	string	A string that describes the schema and has no effect on validation. Starting in MongoDB 5.1, if the `description` field is specified, MongoDB includes the `description` in the error output when a document fails validation.
enum	all types	array of values	Enumerates all possible values of the field
exclusiveMaximum	numbers	boolean	If true and field is a number, `maximum` is an exclusive maximum. Otherwise, it is an inclusive maximum.
exclusiveMinimum	numbers	boolean	If true, `minimum` is an exclusive minimum. Otherwise, it is an inclusive minimum.
items	arrays	object or array	Must be either a valid JSON Schema, or an array of valid JSON Schemas
maximum	numbers	number	Indicates the maximum value of the field
maxItems	arrays	integer	Indicates the maximum length of array
maxLength	strings	integer	Indicates the maximum length of the field
maxProperties	objects	integer	Indicates the field's maximum number of properties
minimum	numbers	number	Indicates the minimum value of the field
minItems	arrays	integer	Indicates the minimum length of array
minLength	strings	integer	Indicates the minimum length of the field
minProperties	objects	integer	Indicates the field's minimum number of properties
multipleOf	numbers	number	Field must be a multiple of this value
not	all types	a JSON Schema object	Field must not match the schema
oneOf	all types	array of JSON Schema objects	Field must match exactly one of the specified schemas
pattern	strings	string containing a regex	Field must match the regular expression
patternProperties	objects	object	In addition to `properties` requirements, each property name of this object must be a valid regular expression
properties	objects	object	A valid JSON Schema where each value is also a valid JSON Schema object
required	objects	array of unique strings	Object's property set must contain all the specified elements in the array
title	N/A	string	A descriptive title string with no effect.
type	all types	string or array of unique strings	Enumerates the possible JSON types of the field. Available types are "object", "array", "number", "boolean", "string", and "null". MongoDB's implementation of the JSON Schema does not support the "integer" type. Use the `bsonType` keyword and the "int" or "long" types instead.
uniqueItems	arrays	boolean	If true, each item in the array must be unique. Otherwise, no uniqueness constraint is enforced.

Extensions

MongoDB's implementation of JSON Schema includes the addition of the bsonType keyword, which allows you to use all BSON types in the $jsonSchema operator. bsonType accepts the same string aliases used for the $type operator.

Omissions

The following are not supported in MongoDB's implementation of JSON Schema:

Hypertext definitions in draft 4 of the JSON Schema spec.
The keywords:
- $ref
- $schema
- default
- definitions
- format
- id
The integer type. You must use the BSON type int or long with the bsonType keyword.
Hypermedia and linking properties of JSON Schema, including the use of JSON References and JSON Pointers.
Unknown keywords.

Examples

For examples using $jsonSchema, see the following pages:

Back

$expr

$mod