MongoDB Extended JSON (v2) (original) (raw)

Important

Disambiguation

JSON can only directly represent a subset of the types supported by BSON. To preserve type information, MongoDB adds the following extensions to the JSON format.

• Canonical Mode
  A string format that emphasizes type preservation at the expense of readability and interoperability. That is, conversion from canonical to BSON will generally preserve type information except in certain specific cases.
• Relaxed Mode
  A string format that emphasizes readability and interoperability at the expense of type preservation. That is, conversion from relaxed format to BSON can lose type information.

Both formats conform to the JSON RFC and can be parsed by the various MongoDB drivers and tools.

The following drivers use the Extended JSON v2.0

For C# and Ruby that use Legacy MongoDB Extended JSON v1, refer toMongoDB Extended JSON (v1).

MongoDB provides the following methods for Extended JSON:

For usage examples, see Extended JSON Object Conversions below.

For additional details, see the documentation for:

• MongoDB NodeJS Driver
• BSON Parser
• BSON-EXT Parser

Starting in version 4.2:

The following presents some common BSON data types and the associated representations in Canonical and Relaxed.

The complete list is here.

Array

Where the array elements are as follows:

• <elements>
  • Array elements use Extended JSON.
  • To specify an empty array, omit the content [ ].

Binary

Where the values are as follows:

• "<payload>"
  • Base64 encoded (with padding as "=") payload string.
• "<t>"
  • A one- or two-character hex string that corresponds to a BSON binary subtype. See the extended bson documentationhttp://bsonspec.org/spec.html for subtypes available.

Date

For dates between years 1970 and 9999, inclusive:

For dates before year 1970 or after year 9999:

Where the values are as follows:

• "<millis>"
  • A 64-bit signed integer as string. The value represents milliseconds relative to the epoch.
• "<ISO-8601 Date/Time Format>"
  • A date in ISO-8601 Internet Date/Time Format as string.
  • The date/time has a maximum time precision of milliseconds:
    * Fractional seconds have exactly 3 decimal places if the fractional part is non-zero.
    * Otherwise, fractional seconds SHOULD be omitted if zero.

Decimal128

Where the values are as follows:

• "<number>"
  • A high-precision decimalas a string.

Document

Where the document contents are as follows:

• <content>
  • Name:value pairs that use Extended JSON.
  • To specify an empty document, omit the content { }.

Double

For finite numbers:

For infinite numbers or NAN:

Where the values are as follows:

• "<decimal string>"
  • A 64-bit signed floating point as a string.
• <non-integer number>
  • A non-integer number. Integer numbers are parsed as an integer instead of a double.

Int64

Where the values are as follows:

• "<number>"
  • A 64-bit signed integer as string.
• <integer>
  • A 64-bit signed integer.

Int32

Where the values are as follows:

• "<number>"
  • A 32-bit signed integer as a string.
• <integer>
  • A 32-bit signed integer.

MaxKey

The MaxKey BSON data type compares higher than all other types. SeeComparison/Sort Order for more information on comparison order for BSON types.

MinKey

The MinKey BSON data type compares lower than all other types. SeeComparison/Sort Order for more information on comparison order for BSON types.

ObjectId

Where the values are as follows:

• "<ObjectId bytes>"
  • A 24-character, big-endian hexadecimal string that represents the ObjectId bytes.

Regular Expression

Where the values are as follows:

• "<regexPattern>"
  • A string that corresponds to the regular expression pattern. The string can contain valid JSON characters and unescaped double quote (") characters, but may not contain unescaped forward slash (/) characters.
• "<options>"
  • A string that specifies BSON regular expression options. You must specify the options in alphabetical order. For information on the supported options, see $options.

Timestamp

Where the values are as follows:

• <t>
  • A positive integer for the seconds since epoch.
• <i>
  • A positive integer for the increment.

The following examples illustrate Extended JSON usage.

The following short examples create a document object and then convert the object to different forms using Extended JSON object conversion methods.

Create a document in the conversions collection:

db.conversions.insertOne( { insertDate: new Date() } )

mongosh returns a document object:

{

  acknowledged: true,

  insertedId: ObjectId("61fbaf25671c45f3f5f4074a")

}

Serialize the data stored in a MongoDB document object:

serialized = EJSON.serialize( db.conversions.findOne() )

mongosh parses a JavaScript object and returns values using"$" prefixed types:

{

  _id: { '$oid': '61fbaf25671c45f3f5f4074a' },

  insertDate: { '$date': '2022-02-03T10:32:05.230Z' }

}

Deserialize a serialized object:

EJSON.deserialize( serialized )

mongosh parses a JavaScript object and returns values using the default mongosh type form:

{

  _id: new ObjectId( "61fbaf25671c45f3f5f4074a" ),

  insertDate: ISODate( "2022-02-03T10:32:05.230Z" )

}

Convert an object to a string:

stringified = EJSON.stringify( db.conversions.findOne() )

mongosh outputs the elements of the converted object as strings:

{

   "_id": {"$oid":"61fbaf25671c45f3f5f4074a"},

   "insertDate":{"$date":"2022-02-03T10:32:05.230Z"}

}

Parse a string to create an object:

EJSON.parse( stringified )

mongosh returns the converted strings as documents:

{

  _id: new ObjectId("61fbaf25671c45f3f5f4074a"),

  insertDate: ISODate("2022-02-03T10:32:05.230Z")

}