bson-rpc
Version:
the nodejs version of bson-rpc
363 lines (317 loc) • 10.3 kB
JavaScript
/**
* Machine id.
*
* Create a random 3-byte value (i.e. unique for this
* process). Other drivers use a md5 of the machine id here, but
* that would mean an asyc call to gethostname, so we don't bother.
* @ignore
*/
var MACHINE_ID = parseInt(Math.random() * 0xFFFFFF, 10);
// Regular expression that checks for hex value
var checkForHexRegExp = new RegExp("^[0-9a-fA-F]{24}$");
var hasBufferType = false;
// Check if buffer exists
try {
if(Buffer && Buffer.from) hasBufferType = true;
} catch(err) {};
/**
* Create a new ObjectID instance
*
* @class
* @param {(string|number)} id Can be a 24 byte hex string, 12 byte binary string or a Number.
* @property {number} generationTime The generation time of this ObjectId instance
* @return {ObjectID} instance of ObjectID.
*/
var ObjectID = function ObjectID(id) {
// Duck-typing to support ObjectId from different npm packages
if(id instanceof ObjectID) return id;
if(!(this instanceof ObjectID)) return new ObjectID(id);
this._bsontype = 'ObjectID';
// The most common usecase (blank id, new objectId instance)
if(id == null || typeof id == 'number') {
// Generate a new id
this.id = this.generate(id);
// If we are caching the hex string
if(ObjectID.cacheHexString) this.__id = this.toString('hex');
// Return the object
return;
}
// Check if the passed in id is valid
var valid = ObjectID.isValid(id);
// Throw an error if it's not a valid setup
if(!valid && id != null){
throw new Error("Argument passed in must be a single String of 12 bytes or a string of 24 hex characters");
} else if(valid && typeof id == 'string' && id.length == 24 && hasBufferType) {
return new ObjectID(new Buffer(id, 'hex'));
} else if(valid && typeof id == 'string' && id.length == 24) {
return ObjectID.createFromHexString(id);
} else if(id != null && id.length === 12) {
// assume 12 byte string
this.id = id;
} else if(id != null && id.toHexString) {
// Duck-typing to support ObjectId from different npm packages
return id;
} else {
throw new Error("Argument passed in must be a single String of 12 bytes or a string of 24 hex characters");
}
if(ObjectID.cacheHexString) this.__id = this.toString('hex');
};
// Allow usage of ObjectId as well as ObjectID
var ObjectId = ObjectID;
// Precomputed hex table enables speedy hex string conversion
var hexTable = [];
for (var i = 0; i < 256; i++) {
hexTable[i] = (i <= 15 ? '0' : '') + i.toString(16);
}
/**
* Return the ObjectID id as a 24 byte hex string representation
*
* @method
* @return {string} return the 24 byte hex string representation.
*/
ObjectID.prototype.toHexString = function() {
if(ObjectID.cacheHexString && this.__id) return this.__id;
var hexString = '';
if(!this.id || !this.id.length) {
throw new Error('invalid ObjectId, ObjectId.id must be either a string or a Buffer, but is [' + JSON.stringify(this.id) + ']');
}
if(this.id instanceof _Buffer) {
hexString = convertToHex(this.id);
if(ObjectID.cacheHexString) this.__id = hexString;
return hexString;
}
for (var i = 0; i < this.id.length; i++) {
hexString += hexTable[this.id.charCodeAt(i)];
}
if(ObjectID.cacheHexString) this.__id = hexString;
return hexString;
};
/**
* Update the ObjectID index used in generating new ObjectID's on the driver
*
* @method
* @return {number} returns next index value.
* @ignore
*/
ObjectID.prototype.get_inc = function() {
return ObjectID.index = (ObjectID.index + 1) % 0xFFFFFF;
};
/**
* Update the ObjectID index used in generating new ObjectID's on the driver
*
* @method
* @return {number} returns next index value.
* @ignore
*/
ObjectID.prototype.getInc = function() {
return this.get_inc();
};
/**
* Generate a 12 byte id buffer used in ObjectID's
*
* @method
* @param {number} [time] optional parameter allowing to pass in a second based timestamp.
* @return {Buffer} return the 12 byte id buffer string.
*/
ObjectID.prototype.generate = function(time) {
if ('number' != typeof time) {
time = ~~(Date.now()/1000);
}
// Use pid
var pid = (typeof process === 'undefined' ? Math.floor(Math.random() * 100000) : process.pid) % 0xFFFF;
var inc = this.get_inc();
// Buffer used
var buffer = new Buffer(12);
// Encode time
buffer[3] = time & 0xff;
buffer[2] = (time >> 8) & 0xff;
buffer[1] = (time >> 16) & 0xff;
buffer[0] = (time >> 24) & 0xff;
// Encode machine
buffer[6] = MACHINE_ID & 0xff;
buffer[5] = (MACHINE_ID >> 8) & 0xff;
buffer[4] = (MACHINE_ID >> 16) & 0xff;
// Encode pid
buffer[8] = pid & 0xff;
buffer[7] = (pid >> 8) & 0xff;
// Encode index
buffer[11] = inc & 0xff;
buffer[10] = (inc >> 8) & 0xff;
buffer[9] = (inc >> 16) & 0xff;
// Return the buffer
return buffer;
};
/**
* Converts the id into a 24 byte hex string for printing
*
* @param {String} format The Buffer toString format parameter.
* @return {String} return the 24 byte hex string representation.
* @ignore
*/
ObjectID.prototype.toString = function(format) {
// Is the id a buffer then use the buffer toString method to return the format
if(this.id && this.id.copy) {
return this.id.toString(typeof format === 'string' ? format : 'hex');
}
// if(this.buffer )
return this.toHexString();
};
/**
* Converts to a string representation of this Id.
*
* @return {String} return the 24 byte hex string representation.
* @ignore
*/
ObjectID.prototype.inspect = ObjectID.prototype.toString;
/**
* Converts to its JSON representation.
*
* @return {String} return the 24 byte hex string representation.
* @ignore
*/
ObjectID.prototype.toJSON = function() {
return this.toHexString();
};
/**
* Compares the equality of this ObjectID with `otherID`.
*
* @method
* @param {object} otherID ObjectID instance to compare against.
* @return {boolean} the result of comparing two ObjectID's
*/
ObjectID.prototype.equals = function equals (otherId) {
var id;
if(otherId instanceof ObjectID) {
return this.toString() == otherId.toString();
} else if(typeof otherId == 'string' && ObjectID.isValid(otherId) && otherId.length == 12 && this.id instanceof _Buffer) {
return otherId === this.id.toString('binary');
} else if(typeof otherId == 'string' && ObjectID.isValid(otherId) && otherId.length == 24) {
return otherId.toLowerCase() === this.toHexString();
} else if(typeof otherId == 'string' && ObjectID.isValid(otherId) && otherId.length == 12) {
return otherId === this.id;
} else if(otherId != null && (otherId instanceof ObjectID || otherId.toHexString)) {
return otherId.toHexString() === this.toHexString();
} else {
return false;
}
}
/**
* Returns the generation date (accurate up to the second) that this ID was generated.
*
* @method
* @return {date} the generation date
*/
ObjectID.prototype.getTimestamp = function() {
var timestamp = new Date();
var time = this.id[3] | this.id[2] << 8 | this.id[1] << 16 | this.id[0] << 24;
timestamp.setTime(Math.floor(time) * 1000);
return timestamp;
}
/**
* @ignore
*/
ObjectID.index = ~~(Math.random() * 0xFFFFFF);
/**
* @ignore
*/
ObjectID.createPk = function createPk () {
return new ObjectID();
};
/**
* Creates an ObjectID from a second based number, with the rest of the ObjectID zeroed out. Used for comparisons or sorting the ObjectID.
*
* @method
* @param {number} time an integer number representing a number of seconds.
* @return {ObjectID} return the created ObjectID
*/
ObjectID.createFromTime = function createFromTime (time) {
var buffer = new Buffer([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]);
// Encode time into first 4 bytes
buffer[3] = time & 0xff;
buffer[2] = (time >> 8) & 0xff;
buffer[1] = (time >> 16) & 0xff;
buffer[0] = (time >> 24) & 0xff;
// Return the new objectId
return new ObjectID(buffer);
};
// Lookup tables
var encodeLookup = '0123456789abcdef'.split('')
var decodeLookup = []
var i = 0
while (i < 10) decodeLookup[0x30 + i] = i++
while (i < 16) decodeLookup[0x41 - 10 + i] = decodeLookup[0x61 - 10 + i] = i++
var _Buffer = Buffer;
var convertToHex = function(bytes) {
return bytes.toString('hex');
}
/**
* Creates an ObjectID from a hex string representation of an ObjectID.
*
* @method
* @param {string} hexString create a ObjectID from a passed in 24 byte hexstring.
* @return {ObjectID} return the created ObjectID
*/
ObjectID.createFromHexString = function createFromHexString (string) {
// Throw an error if it's not a valid setup
if(typeof string === 'undefined' || string != null && string.length != 24) {
throw new Error("Argument passed in must be a single String of 12 bytes or a string of 24 hex characters");
}
// Use Buffer.from method if available
if(hasBufferType) return new ObjectID(new Buffer(string, 'hex'));
// Calculate lengths
var array = new _Buffer(12);
var n = 0;
var i = 0;
while (i < 24) {
array[n++] = decodeLookup[string.charCodeAt(i++)] << 4 | decodeLookup[string.charCodeAt(i++)]
}
return new ObjectID(array);
};
/**
* Checks if a value is a valid bson ObjectId
*
* @method
* @return {boolean} return true if the value is a valid bson ObjectId, return false otherwise.
*/
ObjectID.isValid = function isValid(id) {
if(id == null) return false;
if(typeof id == 'number') {
return true;
}
if(typeof id == 'string') {
return id.length == 12 || (id.length == 24 && checkForHexRegExp.test(id));
}
if(id instanceof ObjectID) {
return true;
}
if(id instanceof _Buffer) {
return true;
}
// Duck-Typing detection of ObjectId like objects
if(id.toHexString) {
return id.id.length == 12 || (id.id.length == 24 && checkForHexRegExp.test(id.id));
}
return false;
};
/**
* @ignore
*/
Object.defineProperty(ObjectID.prototype, "generationTime", {
enumerable: true
, get: function () {
return this.id[3] | this.id[2] << 8 | this.id[1] << 16 | this.id[0] << 24;
}
, set: function (value) {
// Encode time into first 4 bytes
this.id[3] = value & 0xff;
this.id[2] = (value >> 8) & 0xff;
this.id[1] = (value >> 16) & 0xff;
this.id[0] = (value >> 24) & 0xff;
}
});
/**
* Expose.
*/
module.exports = ObjectID;
module.exports.ObjectID = ObjectID;
module.exports.ObjectId = ObjectID;