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$jsonSchema

New in version 3.6.

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

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" }
}
}
}
}
}

For a list of keywords supported by MongoDB, see Available Keywords.

Note

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

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

The featureCompatibilityVersion must be set to "3.6" or higher in order to use $jsonSchema.

You can use $jsonSchema in a document validator to enforce the specified schema on insert and update operations:

db.createCollection( <collection>, { validator: { $jsonSchema: <schema> } } )
db.runCommand( { collMod: <collection>, validator:{ $jsonSchema: <schema> } } )

You can use $jsonSchema in query conditions for read and write operations to find documents in the collection that satisfy the specified schema:

db.collection.find( { $jsonSchema: <schema> } )
db.collection.aggregate( [ { $match: { $jsonSchema: <schema> } } ] )
db.collection.updateMany( { $jsonSchema: <schema> }, <update> )
db.collection.deleteOne( { $jsonSchema: <schema> } )

To find documents in the collection that do not satisfy the specified schema, use the $jsonSchema expression in a $nor expression. For example:

db.collection.find( { $nor: [ { $jsonSchema: <schema> } ] } )
db.collection.aggregate( [ { $match: { $nor: [ { $jsonSchema: <schema> } ] } }, ... ] )
db.collection.updateMany( { $nor: [ { $jsonSchema: <schema> } ] }, <update> )
db.collection.deleteOne( { $nor: [ { $jsonSchema: <schema> } ] } )

The following db.createCollection() method creates a collection named students and uses the $jsonSchema operator to set schema validation rules:

db.createCollection("students", {
validator: {
$jsonSchema: {
bsonType: "object",
required: [ "name", "year", "major", "address" ],
properties: {
name: {
bsonType: "string",
description: "must be a string and is required"
},
year: {
bsonType: "int",
minimum: 2017,
maximum: 3017,
description: "must be an integer in [ 2017, 3017 ] and is required"
},
major: {
enum: [ "Math", "English", "Computer Science", "History", null ],
description: "can only be one of the enum values and is required"
},
gpa: {
bsonType: [ "double" ],
description: "must be a double if the field exists"
},
address: {
bsonType: "object",
required: [ "city" ],
properties: {
street: {
bsonType: "string",
description: "must be a string if the field exists"
},
city: {
bsonType: "string",
"description": "must be a string and is required"
}
}
}
}
}
}
})

Given the created validator for the collection, the following insert operation will fail because gpa is an integer when the validator requires a double.

db.students.insert({
name: "Alice",
year: NumberInt(2019),
major: "History",
gpa: NumberInt(3),
address: {
city: "NYC",
street: "33rd Street"
}
})

The operation returns the following error:

WriteResult({
"nInserted" : 0,
"writeError" : {
"code" : 121,
"errmsg" : "Document failed validation"
}
})

After changing the gpa to a double, the insert succeeds:

db.students.insert({
name: "Alice",
year: NumberInt(2019),
major: "History",
gpa: 3.0,
address: {
city: "NYC",
street: "33rd Street"
}
})

The operation returns the following:

WriteResult({ "nInserted" : 1 })

You can use $jsonSchema in query conditions for read and write operations to find documents in the collection that satisfy the specified schema.

For example, create a sample collection inventory with the following documents:

db.inventory.insertMany([
{ item: "journal", qty: NumberInt(25), size: { h: 14, w: 21, uom: "cm" }, instock: true },
{ item: "notebook", qty: NumberInt(50), size: { h: 8.5, w: 11, uom: "in" }, instock: true },
{ item: "paper", qty: NumberInt(100), size: { h: 8.5, w: 11, uom: "in" }, instock: 1 },
{ item: "planner", qty: NumberInt(75), size: { h: 22.85, w: 30, uom: "cm" }, instock: 1 },
{ item: "postcard", qty: NumberInt(45), size: { h: 10, w: 15.25, uom: "cm" }, instock: true },
{ item: "apple", qty: NumberInt(45), status: "A", instock: true },
{ item: "pears", qty: NumberInt(50), status: "A", instock: true }
])

Next, define the following sample schema object:

let myschema = {
required: [ "item", "qty", "instock" ],
properties: {
item: { bsonType: "string" },
qty: { bsonType: "int" },
size: {
bsonType: "object",
required: [ "uom" ],
properties: {
uom: { bsonType: "string" },
h: { bsonType: "double" },
w: { bsonType: "double" }
}
},
instock: { bsonType: "bool" }
}
}

You can use $jsonSchema to find all documents in the collection that satisfy the schema:

db.inventory.find( { $jsonSchema: myschema } )
db.inventory.aggregate( [ { $match: { $jsonSchema: myschema } } ] )

You can use $jsonSchema with the $nor to find all documents that do not satisfy the schema:

db.inventory.find( { $nor: [ { $jsonSchema: myschema } ] } )

Or, you can update all documents that do not satisfy the schema:

db.inventory.updateMany( { $nor: [ { $jsonSchema: myschema } ] }, { $set: { isValid: false } } )

Or, you can delete all documents that do not satisfy the schema:

db.inventory.deleteMany( { $nor: [ { $jsonSchema: myschema } ] } )

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

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

Note

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

Keyword
Type
Definition
Behavior
bsonType
all types
string alias or array of string aliases
Accepts same string aliases used for the $type operator
enum
all types
array of values
Enumerates all possible values of the field
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.

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
oneOf
all types
array of JSON Schema objects
Field must match exactly one of the specified schemas
not
all types
a JSON Schema object
Field must not match the schema
multipleOf
numbers
number
Field must be a multiple of this value
maximum
numbers
number
Indicates the maximum value of the field
exclusiveMaximum
numbers
boolean
If true and field is a number, maximum is an exclusive maximum. Otherwise, it is an inclusive maximum.
minimum
numbers
number
Indicates the minimum value of the field
exclusiveMinimum
numbers
boolean
If true, minimum is an exclusive minimum. Otherwise, it is an inclusive minimum.
maxLength
strings
integer
Indicates the maximum length of the field
minLength
strings
integer
Indicates the minimum length of the field
pattern
strings
string containing a regex
Field must match the regular expression
maxProperties
objects
integer
Indicates the field's maximum number of properties
minProperties
objects
integer
Indicates the field's minimum number of properties
required
objects
array of unique strings
Object's property set must contain all the specified elements in the array
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.

properties
objects
object
A valid JSON Schema where each value is also a valid JSON Schema object
patternProperties
objects
object
In addition to properties requirements, each property name of this object must be a valid regular expression
dependencies
objects
object
Describes field or schema dependencies
additionalItems
arrays
boolean or object
If an object, must be a valid JSON Schema
items
arrays
object or array
Must be either a valid JSON Schema, or an array of valid JSON Schemas
maxItems
arrays
integer
Indicates the maximum length of array
minItems
arrays
integer
Indicates the minimum length of array
uniqueItems
arrays
boolean
If true, each item in the array must be unique. Otherwise, no uniqueness constraint is enforced.
title
N/A
string
A descriptive title string with no effect.
description
N/A
string
A string that describes the schema and has no effect.

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.

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.
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