bson-buffer

Fork disclaimer

This is a fork with breaking changes!

This is a fork of the mongodb js-bson project located at https://github.com/mongodb/js-bson). The modifications are simple, but breaks compatibility with the original software.

See the BSON-buffer changes section for more details.

BSON parser

If you don't yet know what BSON actually is, read the spec.

The browser version of the BSON parser is compiled using webpack and the current version is pre-compiled in the browser_build directory. To build a new version perform the following operation.

npm install
npm run build

A simple example of how to use BSON in the browser:

<script src="./browser_build/bson.js"></script>

<script>
  function start() {
    // Get the Long type
    var Long = BSON.Long;
    // Create a bson parser instance
    var bson = new BSON();

    // Serialize document
    var doc = { long: Long.fromNumber(100) }

    // Serialize a document
    var data = bson.serialize(doc)
    // De serialize it again
    var doc_2 = bson.deserialize(data)
  }
</script>

A simple example of how to use BSON in node.js:

// Get BSON parser class
var BSON = require('bson')
// Get the Long type
var Long = BSON.Long;
// Create a bson parser instance
var bson = new BSON();

// Serialize document
var doc = { long: Long.fromNumber(100) }

// Serialize a document
var data = bson.serialize(doc)
console.log('data:', data)

// Deserialize the resulting Buffer
var doc_2 = bson.deserialize(data)
console.log('doc_2:', doc_2)

Installation

npm install bson-ext

API

BSON types

For all BSON types documentation, please refer to the documentation for the mongodb driver.

https://github.com/mongodb/node-mongodb-native

BSON serialization and deserialiation

new BSON() - Creates a new BSON seralizer/deserializer you can use to serialize and deserialize BSON.

BSON.serialize

The BSON serialize method takes a javascript object and an optional options object and returns a Node.js Buffer.

• BSON.serialize(object, options)
  • @param {Object} object the Javascript object to serialize.
  • @param {Boolean} [options.checkKeys=false] the serializer will check if keys are valid.
  • @param {Boolean} [options.serializeFunctions=false] serialize the javascript. functions.
  • @param {Boolean} [options.ignoreUndefined=true]
  • @return {Buffer} returns a Buffer instance.

BSON.serializeWithBufferAndIndex

The BSON serializeWithBufferAndIndex method takes an object, a target buffer instance and an optional options object and returns the end serialization index in the final buffer.

• BSON.serializeWithBufferAndIndex(object, buffer, options)
  • @param {Object} object the Javascript object to serialize.
  • @param {Buffer} buffer the Buffer you pre-allocated to store the serialized BSON object.
  • @param {Boolean} [options.checkKeys=false] the serializer will check if keys are valid.
  • @param {Boolean} [options.serializeFunctions=false] serialize the javascript functions.
  • @param {Boolean} [options.ignoreUndefined=true] ignore undefined fields.
  • @param {Number} [options.index=0] the index in the buffer where we wish to start serializing into.
  • @return {Number} returns the index pointing to the last written byte in the buffer.

BSON.calculateObjectSize

The BSON calculateObjectSize method takes a javascript object and an optional options object and returns the size of the BSON object.

• BSON.calculateObjectSize(object, options)
  • @param {Object} object the Javascript object to serialize.
  • @param {Boolean} [options.serializeFunctions=false] serialize the javascript. functions.
  • @param {Boolean} [options.ignoreUndefined=true]
  • @return {Buffer} returns a Buffer instance.

BSON.deserialize

The BSON deserialize method takes a node.js Buffer and an optional options object and returns a deserialized Javascript object.

• BSON.deserialize(buffer, options)
  • @param {Object} [options.evalFunctions=false] evaluate functions in the BSON document scoped to the object deserialized.
  • @param {Object} [options.cacheFunctions=false] cache evaluated functions for reuse.
  • @param {Object} [options.cacheFunctionsCrc32=false] use a crc32 code for caching, otherwise use the string of the function.
  • @param {Object} [options.promoteLongs=true] when deserializing a Long will fit it into a Number if it's smaller than 53 bits
  • @param {Object} [options.promoteBuffers=false] when deserializing a Binary will return it as a node.js Buffer instance.
  • @param {Object} [options.promoteValues=false] when deserializing will promote BSON values to their Node.js closest equivalent types.
  • @param {Object} [options.fieldsAsRaw=null] allow to specify if there what fields we wish to return as unserialized raw buffer.
  • @param {Object} [options.bsonRegExp=false] return BSON regular expressions as BSONRegExp instances.
  • @return {Number} returns the next index in the buffer after deserialization x numbers of documents.

BSON.deserializeStream

The BSON deserializeStream method takes a node.js Buffer, startIndex and allow more control over deserialization of a Buffer containing concatenated BSON documents.

• BSON.deserializeStream(buffer, startIndex, numberOfDocuments, documents, docStartIndex, options)
  • @param {Buffer} buffer the buffer containing the serialized set of BSON documents.
  • @param {Number} startIndex the start index in the data Buffer where the deserialization is to start.
  • @param {Number} numberOfDocuments number of documents to deserialize.
  • @param {Array} documents an array where to store the deserialized documents.
  • @param {Number} docStartIndex the index in the documents array from where to start inserting documents.
  • @param {Object} [options.evalFunctions=false] evaluate functions in the BSON document scoped to the object deserialized.
  • @param {Object} [options.cacheFunctions=false] cache evaluated functions for reuse.
  • @param {Object} [options.cacheFunctionsCrc32=false] use a crc32 code for caching, otherwise use the string of the function.
  • @param {Object} [options.promoteLongs=true] when deserializing a Long will fit it into a Number if it's smaller than 53 bits
  • @param {Object} [options.promoteBuffers=false] when deserializing a Binary will return it as a node.js Buffer instance.
  • @param {Object} [options.promoteValues=false] when deserializing will promote BSON values to their Node.js closest equivalent types.
  • @param {Object} [options.fieldsAsRaw=null] allow to specify if there what fields we wish to return as unserialized raw buffer.
  • @param {Object} [options.bsonRegExp=false] return BSON regular expressions as BSONRegExp instances.
  • @return {Object} returns the deserialized Javascript Object.

BSON-buffer changes

The purpose of this fork is to introduce direct conversion of BSON type Binary to Buffer and vice versa. In the browser it uses Uint8Array instead of Buffer, but the general idea is the same. This only works reliably if there is only need for a single subtype.

Example:

var in = { payload: new Buffer('00FF00FF00FF', 'hex') }

var ser = BSON.serialize(in);

var out = BSON.deserialize(ser);

Value of out in this fork implementation

{ payload: Buffer } // '00FF00FF00FF'

Value of out in original implementation

{ payload: {
  _bsonType: 'Binary', 
  sub_type: BSON_BINARY_SUBTYPE_DEFAULT, 
  buffer: Buffer } } // '00FF00FF00FF'