mongodb
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The official MongoDB driver for Node.js
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JavaScript
"use strict";
/**
* @fileOverview GridFS is a tool for MongoDB to store files to the database.
* Because of the restrictions of the object size the database can hold, a
* facility to split a file into several chunks is needed. The {@link GridStore}
* class offers a simplified api to interact with files while managing the
* chunks of split files behind the scenes. More information about GridFS can be
* found <a href="http://www.mongodb.org/display/DOCS/GridFS">here</a>.
*
* @example
* var MongoClient = require('mongodb').MongoClient,
* GridStore = require('mongodb').GridStore,
* ObjectID = require('mongodb').ObjectID,
* test = require('assert');
*
* // Connection url
* var url = 'mongodb://localhost:27017/test';
* // Connect using MongoClient
* MongoClient.connect(url, function(err, db) {
* var gridStore = new GridStore(db, null, "w");
* gridStore.open(function(err, gridStore) {
* gridStore.write("hello world!", function(err, gridStore) {
* gridStore.close(function(err, result) {
*
* // Let's read the file using object Id
* GridStore.read(db, result._id, function(err, data) {
* test.equal('hello world!', data);
* db.close();
* test.done();
* });
* });
* });
* });
* });
*/
var Chunk = require('./chunk'),
ObjectID = require('mongodb-core').BSON.ObjectID,
ReadPreference = require('../read_preference'),
Buffer = require('buffer').Buffer,
Collection = require('../collection'),
fs = require('fs'),
f = require('util').format,
util = require('util'),
Define = require('../metadata'),
MongoError = require('mongodb-core').MongoError,
inherits = util.inherits,
Duplex = require('stream').Duplex || require('readable-stream').Duplex,
shallowClone = require('../utils').shallowClone;
var REFERENCE_BY_FILENAME = 0,
REFERENCE_BY_ID = 1;
/**
* Namespace provided by the mongodb-core and node.js
* @external Duplex
*/
/**
* Create a new GridStore instance
*
* Modes
* - **"r"** - read only. This is the default mode.
* - **"w"** - write in truncate mode. Existing data will be overwriten.
*
* @class
* @param {Db} db A database instance to interact with.
* @param {object} [id] optional unique id for this file
* @param {string} [filename] optional filename for this file, no unique constrain on the field
* @param {string} mode set the mode for this file.
* @param {object} [options=null] Optional settings.
* @param {(number|string)} [options.w=null] The write concern.
* @param {number} [options.wtimeout=null] The write concern timeout.
* @param {boolean} [options.j=false] Specify a journal write concern.
* @param {boolean} [options.fsync=false] Specify a file sync write concern.
* @param {string} [options.root=null] Root collection to use. Defaults to **{GridStore.DEFAULT_ROOT_COLLECTION}**.
* @param {string} [options.content_type=null] MIME type of the file. Defaults to **{GridStore.DEFAULT_CONTENT_TYPE}**.
* @param {number} [options.chunk_size=261120] Size for the chunk. Defaults to **{Chunk.DEFAULT_CHUNK_SIZE}**.
* @param {object} [options.metadata=null] Arbitrary data the user wants to store.
* @param {object} [options.promiseLibrary=null] A Promise library class the application wishes to use such as Bluebird, must be ES6 compatible
* @param {(ReadPreference|string)} [options.readPreference=null] The preferred read preference (ReadPreference.PRIMARY, ReadPreference.PRIMARY_PREFERRED, ReadPreference.SECONDARY, ReadPreference.SECONDARY_PREFERRED, ReadPreference.NEAREST).
* @property {number} chunkSize Get the gridstore chunk size.
* @property {number} md5 The md5 checksum for this file.
* @property {number} chunkNumber The current chunk number the gridstore has materialized into memory
* @return {GridStore} a GridStore instance.
* @deprecated Use GridFSBucket API instead
*/
var GridStore = function GridStore(db, id, filename, mode, options) {
if(!(this instanceof GridStore)) return new GridStore(db, id, filename, mode, options);
this.db = db;
// Handle options
if(typeof options === 'undefined') options = {};
// Handle mode
if(typeof mode === 'undefined') {
mode = filename;
filename = undefined;
} else if(typeof mode == 'object') {
options = mode;
mode = filename;
filename = undefined;
}
if(id && id._bsontype == 'ObjectID') {
this.referenceBy = REFERENCE_BY_ID;
this.fileId = id;
this.filename = filename;
} else if(typeof filename == 'undefined') {
this.referenceBy = REFERENCE_BY_FILENAME;
this.filename = id;
if (mode.indexOf('w') != null) {
this.fileId = new ObjectID();
}
} else {
this.referenceBy = REFERENCE_BY_ID;
this.fileId = id;
this.filename = filename;
}
// Set up the rest
this.mode = mode == null ? "r" : mode;
this.options = options || {};
// Opened
this.isOpen = false;
// Set the root if overridden
this.root = this.options['root'] == null ? GridStore.DEFAULT_ROOT_COLLECTION : this.options['root'];
this.position = 0;
this.readPreference = this.options.readPreference || db.options.readPreference || ReadPreference.PRIMARY;
this.writeConcern = _getWriteConcern(db, this.options);
// Set default chunk size
this.internalChunkSize = this.options['chunkSize'] == null ? Chunk.DEFAULT_CHUNK_SIZE : this.options['chunkSize'];
// Get the promiseLibrary
var promiseLibrary = this.options.promiseLibrary;
// No promise library selected fall back
if(!promiseLibrary) {
promiseLibrary = typeof global.Promise == 'function' ?
global.Promise : require('es6-promise').Promise;
}
// Set the promiseLibrary
this.promiseLibrary = promiseLibrary;
Object.defineProperty(this, "chunkSize", { enumerable: true
, get: function () {
return this.internalChunkSize;
}
, set: function(value) {
if(!(this.mode[0] == "w" && this.position == 0 && this.uploadDate == null)) {
this.internalChunkSize = this.internalChunkSize;
} else {
this.internalChunkSize = value;
}
}
});
Object.defineProperty(this, "md5", { enumerable: true
, get: function () {
return this.internalMd5;
}
});
Object.defineProperty(this, "chunkNumber", { enumerable: true
, get: function () {
return this.currentChunk && this.currentChunk.chunkNumber ? this.currentChunk.chunkNumber : null;
}
});
}
var define = GridStore.define = new Define('Gridstore', GridStore, true);
/**
* The callback format for the Gridstore.open method
* @callback GridStore~openCallback
* @param {MongoError} error An error instance representing the error during the execution.
* @param {GridStore} gridStore The GridStore instance if the open method was successful.
*/
/**
* Opens the file from the database and initialize this object. Also creates a
* new one if file does not exist.
*
* @method
* @param {GridStore~openCallback} [callback] this will be called after executing this method
* @return {Promise} returns Promise if no callback passed
* @deprecated Use GridFSBucket API instead
*/
GridStore.prototype.open = function(callback) {
var self = this;
if( this.mode != "w" && this.mode != "w+" && this.mode != "r"){
throw MongoError.create({message: "Illegal mode " + this.mode, driver:true});
}
// We provided a callback leg
if(typeof callback == 'function') return open(self, callback);
// Return promise
return new self.promiseLibrary(function(resolve, reject) {
open(self, function(err, store) {
if(err) return reject(err);
resolve(store);
})
});
};
var open = function(self, callback) {
// Get the write concern
var writeConcern = _getWriteConcern(self.db, self.options);
// If we are writing we need to ensure we have the right indexes for md5's
if((self.mode == "w" || self.mode == "w+")) {
// Get files collection
var collection = self.collection();
// Put index on filename
collection.ensureIndex([['filename', 1]], writeConcern, function() {
// Get chunk collection
var chunkCollection = self.chunkCollection();
// Make an unique index for compatibility with mongo-cxx-driver:legacy
var chunkIndexOptions = shallowClone(writeConcern);
chunkIndexOptions.unique = true;
// Ensure index on chunk collection
chunkCollection.ensureIndex([['files_id', 1], ['n', 1]], chunkIndexOptions, function() {
// Open the connection
_open(self, writeConcern, function(err, r) {
if(err) return callback(err);
self.isOpen = true;
callback(err, r);
});
});
});
} else {
// Open the gridstore
_open(self, writeConcern, function(err, r) {
if(err) return callback(err);
self.isOpen = true;
callback(err, r);
});
}
}
// Push the definition for open
define.classMethod('open', {callback: true, promise:true});
/**
* Verify if the file is at EOF.
*
* @method
* @return {boolean} true if the read/write head is at the end of this file.
* @deprecated Use GridFSBucket API instead
*/
GridStore.prototype.eof = function() {
return this.position == this.length ? true : false;
}
define.classMethod('eof', {callback: false, promise:false, returns: [Boolean]});
/**
* The callback result format.
* @callback GridStore~resultCallback
* @param {MongoError} error An error instance representing the error during the execution.
* @param {object} result The result from the callback.
*/
/**
* Retrieves a single character from this file.
*
* @method
* @param {GridStore~resultCallback} [callback] this gets called after this method is executed. Passes null to the first parameter and the character read to the second or null to the second if the read/write head is at the end of the file.
* @return {Promise} returns Promise if no callback passed
* @deprecated Use GridFSBucket API instead
*/
GridStore.prototype.getc = function(callback) {
var self = this;
// We provided a callback leg
if(typeof callback == 'function') return eof(self, callback);
// Return promise
return new self.promiseLibrary(function(resolve, reject) {
eof(self, function(err, r) {
if(err) return reject(err);
resolve(r);
})
});
}
var eof = function(self, callback) {
if(self.eof()) {
callback(null, null);
} else if(self.currentChunk.eof()) {
nthChunk(self, self.currentChunk.chunkNumber + 1, function(err, chunk) {
self.currentChunk = chunk;
self.position = self.position + 1;
callback(err, self.currentChunk.getc());
});
} else {
self.position = self.position + 1;
callback(null, self.currentChunk.getc());
}
}
define.classMethod('getc', {callback: true, promise:true});
/**
* Writes a string to the file with a newline character appended at the end if
* the given string does not have one.
*
* @method
* @param {string} string the string to write.
* @param {GridStore~resultCallback} [callback] this will be called after executing this method. The first parameter will contain null and the second one will contain a reference to this object.
* @return {Promise} returns Promise if no callback passed
* @deprecated Use GridFSBucket API instead
*/
GridStore.prototype.puts = function(string, callback) {
var self = this;
var finalString = string.match(/\n$/) == null ? string + "\n" : string;
// We provided a callback leg
if(typeof callback == 'function') return this.write(finalString, callback);
// Return promise
return new self.promiseLibrary(function(resolve, reject) {
self.write(finalString, function(err, r) {
if(err) return reject(err);
resolve(r);
})
});
}
define.classMethod('puts', {callback: true, promise:true});
/**
* Return a modified Readable stream including a possible transform method.
*
* @method
* @return {GridStoreStream}
* @deprecated Use GridFSBucket API instead
*/
GridStore.prototype.stream = function() {
return new GridStoreStream(this);
}
define.classMethod('stream', {callback: false, promise:false, returns: [GridStoreStream]});
/**
* Writes some data. This method will work properly only if initialized with mode "w" or "w+".
*
* @method
* @param {(string|Buffer)} data the data to write.
* @param {boolean} [close] closes this file after writing if set to true.
* @param {GridStore~resultCallback} [callback] this will be called after executing this method. The first parameter will contain null and the second one will contain a reference to this object.
* @return {Promise} returns Promise if no callback passed
* @deprecated Use GridFSBucket API instead
*/
GridStore.prototype.write = function write(data, close, callback) {
var self = this;
// We provided a callback leg
if(typeof callback == 'function') return _writeNormal(this, data, close, callback);
// Return promise
return new self.promiseLibrary(function(resolve, reject) {
_writeNormal(self, data, close, function(err, r) {
if(err) return reject(err);
resolve(r);
})
});
}
define.classMethod('write', {callback: true, promise:true});
/**
* Handles the destroy part of a stream
*
* @method
* @result {null}
* @deprecated Use GridFSBucket API instead
*/
GridStore.prototype.destroy = function destroy() {
// close and do not emit any more events. queued data is not sent.
if(!this.writable) return;
this.readable = false;
if(this.writable) {
this.writable = false;
this._q.length = 0;
this.emit('close');
}
}
define.classMethod('destroy', {callback: false, promise:false});
/**
* Stores a file from the file system to the GridFS database.
*
* @method
* @param {(string|Buffer|FileHandle)} file the file to store.
* @param {GridStore~resultCallback} [callback] this will be called after executing this method. The first parameter will contain null and the second one will contain a reference to this object.
* @return {Promise} returns Promise if no callback passed
* @deprecated Use GridFSBucket API instead
*/
GridStore.prototype.writeFile = function (file, callback) {
var self = this;
// We provided a callback leg
if(typeof callback == 'function') return writeFile(self, file, callback);
// Return promise
return new self.promiseLibrary(function(resolve, reject) {
writeFile(self, file, function(err, r) {
if(err) return reject(err);
resolve(r);
})
});
};
var writeFile = function(self, file, callback) {
if (typeof file === 'string') {
fs.open(file, 'r', function (err, fd) {
if(err) return callback(err);
self.writeFile(fd, callback);
});
return;
}
self.open(function (err, self) {
if(err) return callback(err, self);
fs.fstat(file, function (err, stats) {
if(err) return callback(err, self);
var offset = 0;
var index = 0;
// Write a chunk
var writeChunk = function() {
fs.read(file, self.chunkSize, offset, 'binary', function(err, data, bytesRead) {
if(err) return callback(err, self);
offset = offset + bytesRead;
// Create a new chunk for the data
var chunk = new Chunk(self, {n:index++}, self.writeConcern);
chunk.write(data, function(err, chunk) {
if(err) return callback(err, self);
chunk.save({}, function(err) {
if(err) return callback(err, self);
self.position = self.position + data.length;
// Point to current chunk
self.currentChunk = chunk;
if(offset >= stats.size) {
fs.close(file);
self.close(function(err) {
if(err) return callback(err, self);
return callback(null, self);
});
} else {
return process.nextTick(writeChunk);
}
});
});
});
}
// Process the first write
process.nextTick(writeChunk);
});
});
}
define.classMethod('writeFile', {callback: true, promise:true});
/**
* Saves this file to the database. This will overwrite the old entry if it
* already exists. This will work properly only if mode was initialized to
* "w" or "w+".
*
* @method
* @param {GridStore~resultCallback} [callback] this will be called after executing this method. The first parameter will contain null and the second one will contain a reference to this object.
* @return {Promise} returns Promise if no callback passed
* @deprecated Use GridFSBucket API instead
*/
GridStore.prototype.close = function(callback) {
var self = this;
// We provided a callback leg
if(typeof callback == 'function') return close(self, callback);
// Return promise
return new self.promiseLibrary(function(resolve, reject) {
close(self, function(err, r) {
if(err) return reject(err);
resolve(r);
})
});
};
var close = function(self, callback) {
if(self.mode[0] == "w") {
// Set up options
var options = self.writeConcern;
if(self.currentChunk != null && self.currentChunk.position > 0) {
self.currentChunk.save({}, function(err) {
if(err && typeof callback == 'function') return callback(err);
self.collection(function(err, files) {
if(err && typeof callback == 'function') return callback(err);
// Build the mongo object
if(self.uploadDate != null) {
buildMongoObject(self, function(err, mongoObject) {
if(err) {
if(typeof callback == 'function') return callback(err); else throw err;
}
files.save(mongoObject, options, function(err) {
if(typeof callback == 'function')
callback(err, mongoObject);
});
});
} else {
self.uploadDate = new Date();
buildMongoObject(self, function(err, mongoObject) {
if(err) {
if(typeof callback == 'function') return callback(err); else throw err;
}
files.save(mongoObject, options, function(err) {
if(typeof callback == 'function')
callback(err, mongoObject);
});
});
}
});
});
} else {
self.collection(function(err, files) {
if(err && typeof callback == 'function') return callback(err);
self.uploadDate = new Date();
buildMongoObject(self, function(err, mongoObject) {
if(err) {
if(typeof callback == 'function') return callback(err); else throw err;
}
files.save(mongoObject, options, function(err) {
if(typeof callback == 'function')
callback(err, mongoObject);
});
});
});
}
} else if(self.mode[0] == "r") {
if(typeof callback == 'function')
callback(null, null);
} else {
if(typeof callback == 'function')
callback(MongoError.create({message: f("Illegal mode %s", self.mode), driver:true}));
}
}
define.classMethod('close', {callback: true, promise:true});
/**
* The collection callback format.
* @callback GridStore~collectionCallback
* @param {MongoError} error An error instance representing the error during the execution.
* @param {Collection} collection The collection from the command execution.
*/
/**
* Retrieve this file's chunks collection.
*
* @method
* @param {GridStore~collectionCallback} callback the command callback.
* @return {Collection}
* @deprecated Use GridFSBucket API instead
*/
GridStore.prototype.chunkCollection = function(callback) {
if(typeof callback == 'function')
return this.db.collection((this.root + ".chunks"), callback);
return this.db.collection((this.root + ".chunks"));
};
define.classMethod('chunkCollection', {callback: true, promise:false, returns: [Collection]});
/**
* Deletes all the chunks of this file in the database.
*
* @method
* @param {GridStore~resultCallback} [callback] the command callback.
* @return {Promise} returns Promise if no callback passed
* @deprecated Use GridFSBucket API instead
*/
GridStore.prototype.unlink = function(callback) {
var self = this;
// We provided a callback leg
if(typeof callback == 'function') return unlink(self, callback);
// Return promise
return new self.promiseLibrary(function(resolve, reject) {
unlink(self, function(err, r) {
if(err) return reject(err);
resolve(r);
})
});
};
var unlink = function(self, callback) {
deleteChunks(self, function(err) {
if(err!==null) {
err.message = "at deleteChunks: " + err.message;
return callback(err);
}
self.collection(function(err, collection) {
if(err!==null) {
err.message = "at collection: " + err.message;
return callback(err);
}
collection.remove({'_id':self.fileId}, self.writeConcern, function(err) {
callback(err, self);
});
});
});
}
define.classMethod('unlink', {callback: true, promise:true});
/**
* Retrieves the file collection associated with this object.
*
* @method
* @param {GridStore~collectionCallback} callback the command callback.
* @return {Collection}
* @deprecated Use GridFSBucket API instead
*/
GridStore.prototype.collection = function(callback) {
if(typeof callback == 'function')
this.db.collection(this.root + ".files", callback);
return this.db.collection(this.root + ".files");
};
define.classMethod('collection', {callback: true, promise:false, returns: [Collection]});
/**
* The readlines callback format.
* @callback GridStore~readlinesCallback
* @param {MongoError} error An error instance representing the error during the execution.
* @param {string[]} strings The array of strings returned.
*/
/**
* Read the entire file as a list of strings splitting by the provided separator.
*
* @method
* @param {string} [separator] The character to be recognized as the newline separator.
* @param {GridStore~readlinesCallback} [callback] the command callback.
* @return {Promise} returns Promise if no callback passed
* @deprecated Use GridFSBucket API instead
*/
GridStore.prototype.readlines = function(separator, callback) {
var self = this;
var args = Array.prototype.slice.call(arguments, 0);
callback = args.pop();
if(typeof callback != 'function') args.push(callback);
separator = args.length ? args.shift() : "\n";
separator = separator || "\n";
// We provided a callback leg
if(typeof callback == 'function') return readlines(self, separator, callback);
// Return promise
return new self.promiseLibrary(function(resolve, reject) {
readlines(self, separator, function(err, r) {
if(err) return reject(err);
resolve(r);
})
});
};
var readlines = function(self, separator, callback) {
self.read(function(err, data) {
if(err) return callback(err);
var items = data.toString().split(separator);
items = items.length > 0 ? items.splice(0, items.length - 1) : [];
for(var i = 0; i < items.length; i++) {
items[i] = items[i] + separator;
}
callback(null, items);
});
}
define.classMethod('readlines', {callback: true, promise:true});
/**
* Deletes all the chunks of this file in the database if mode was set to "w" or
* "w+" and resets the read/write head to the initial position.
*
* @method
* @param {GridStore~resultCallback} [callback] this will be called after executing this method. The first parameter will contain null and the second one will contain a reference to this object.
* @return {Promise} returns Promise if no callback passed
* @deprecated Use GridFSBucket API instead
*/
GridStore.prototype.rewind = function(callback) {
var self = this;
// We provided a callback leg
if(typeof callback == 'function') return rewind(self, callback);
// Return promise
return new self.promiseLibrary(function(resolve, reject) {
rewind(self, function(err, r) {
if(err) return reject(err);
resolve(r);
})
});
};
var rewind = function(self, callback) {
if(self.currentChunk.chunkNumber != 0) {
if(self.mode[0] == "w") {
deleteChunks(self, function(err) {
if(err) return callback(err);
self.currentChunk = new Chunk(self, {'n': 0}, self.writeConcern);
self.position = 0;
callback(null, self);
});
} else {
self.currentChunk(0, function(err, chunk) {
if(err) return callback(err);
self.currentChunk = chunk;
self.currentChunk.rewind();
self.position = 0;
callback(null, self);
});
}
} else {
self.currentChunk.rewind();
self.position = 0;
callback(null, self);
}
}
define.classMethod('rewind', {callback: true, promise:true});
/**
* The read callback format.
* @callback GridStore~readCallback
* @param {MongoError} error An error instance representing the error during the execution.
* @param {Buffer} data The data read from the GridStore object
*/
/**
* Retrieves the contents of this file and advances the read/write head. Works with Buffers only.
*
* There are 3 signatures for this method:
*
* (callback)
* (length, callback)
* (length, buffer, callback)
*
* @method
* @param {number} [length] the number of characters to read. Reads all the characters from the read/write head to the EOF if not specified.
* @param {(string|Buffer)} [buffer] a string to hold temporary data. This is used for storing the string data read so far when recursively calling this method.
* @param {GridStore~readCallback} [callback] the command callback.
* @return {Promise} returns Promise if no callback passed
* @deprecated Use GridFSBucket API instead
*/
GridStore.prototype.read = function(length, buffer, callback) {
var self = this;
var args = Array.prototype.slice.call(arguments, 0);
callback = args.pop();
if(typeof callback != 'function') args.push(callback);
length = args.length ? args.shift() : null;
buffer = args.length ? args.shift() : null;
// We provided a callback leg
if(typeof callback == 'function') return read(self, length, buffer, callback);
// Return promise
return new self.promiseLibrary(function(resolve, reject) {
read(self, length, buffer, function(err, r) {
if(err) return reject(err);
resolve(r);
})
});
}
var read = function(self, length, buffer, callback) {
// The data is a c-terminated string and thus the length - 1
var finalLength = length == null ? self.length - self.position : length;
var finalBuffer = buffer == null ? new Buffer(finalLength) : buffer;
// Add a index to buffer to keep track of writing position or apply current index
finalBuffer._index = buffer != null && buffer._index != null ? buffer._index : 0;
if((self.currentChunk.length() - self.currentChunk.position + finalBuffer._index) >= finalLength) {
var slice = self.currentChunk.readSlice(finalLength - finalBuffer._index);
// Copy content to final buffer
slice.copy(finalBuffer, finalBuffer._index);
// Update internal position
self.position = self.position + finalBuffer.length;
// Check if we don't have a file at all
if(finalLength == 0 && finalBuffer.length == 0) return callback(MongoError.create({message: "File does not exist", driver:true}), null);
// Else return data
return callback(null, finalBuffer);
}
// Read the next chunk
slice = self.currentChunk.readSlice(self.currentChunk.length() - self.currentChunk.position);
// Copy content to final buffer
slice.copy(finalBuffer, finalBuffer._index);
// Update index position
finalBuffer._index += slice.length;
// Load next chunk and read more
nthChunk(self, self.currentChunk.chunkNumber + 1, function(err, chunk) {
if(err) return callback(err);
if(chunk.length() > 0) {
self.currentChunk = chunk;
self.read(length, finalBuffer, callback);
} else {
if(finalBuffer._index > 0) {
callback(null, finalBuffer)
} else {
callback(MongoError.create({message: "no chunks found for file, possibly corrupt", driver:true}), null);
}
}
});
}
define.classMethod('read', {callback: true, promise:true});
/**
* The tell callback format.
* @callback GridStore~tellCallback
* @param {MongoError} error An error instance representing the error during the execution.
* @param {number} position The current read position in the GridStore.
*/
/**
* Retrieves the position of the read/write head of this file.
*
* @method
* @param {number} [length] the number of characters to read. Reads all the characters from the read/write head to the EOF if not specified.
* @param {(string|Buffer)} [buffer] a string to hold temporary data. This is used for storing the string data read so far when recursively calling this method.
* @param {GridStore~tellCallback} [callback] the command callback.
* @return {Promise} returns Promise if no callback passed
* @deprecated Use GridFSBucket API instead
*/
GridStore.prototype.tell = function(callback) {
var self = this;
// We provided a callback leg
if(typeof callback == 'function') return callback(null, this.position);
// Return promise
return new self.promiseLibrary(function(resolve) {
resolve(self.position);
});
};
define.classMethod('tell', {callback: true, promise:true});
/**
* The tell callback format.
* @callback GridStore~gridStoreCallback
* @param {MongoError} error An error instance representing the error during the execution.
* @param {GridStore} gridStore The gridStore.
*/
/**
* Moves the read/write head to a new location.
*
* There are 3 signatures for this method
*
* Seek Location Modes
* - **GridStore.IO_SEEK_SET**, **(default)** set the position from the start of the file.
* - **GridStore.IO_SEEK_CUR**, set the position from the current position in the file.
* - **GridStore.IO_SEEK_END**, set the position from the end of the file.
*
* @method
* @param {number} [position] the position to seek to
* @param {number} [seekLocation] seek mode. Use one of the Seek Location modes.
* @param {GridStore~gridStoreCallback} [callback] the command callback.
* @return {Promise} returns Promise if no callback passed
* @deprecated Use GridFSBucket API instead
*/
GridStore.prototype.seek = function(position, seekLocation, callback) {
var self = this;
var args = Array.prototype.slice.call(arguments, 1);
callback = args.pop();
if(typeof callback != 'function') args.push(callback);
seekLocation = args.length ? args.shift() : null;
// We provided a callback leg
if(typeof callback == 'function') return seek(self, position, seekLocation, callback);
// Return promise
return new self.promiseLibrary(function(resolve, reject) {
seek(self, position, seekLocation, function(err, r) {
if(err) return reject(err);
resolve(r);
})
});
}
var seek = function(self, position, seekLocation, callback) {
// Seek only supports read mode
if(self.mode != 'r') {
return callback(MongoError.create({message: "seek is only supported for mode r", driver:true}))
}
var seekLocationFinal = seekLocation == null ? GridStore.IO_SEEK_SET : seekLocation;
var finalPosition = position;
var targetPosition = 0;
// Calculate the position
if(seekLocationFinal == GridStore.IO_SEEK_CUR) {
targetPosition = self.position + finalPosition;
} else if(seekLocationFinal == GridStore.IO_SEEK_END) {
targetPosition = self.length + finalPosition;
} else {
targetPosition = finalPosition;
}
// Get the chunk
var newChunkNumber = Math.floor(targetPosition/self.chunkSize);
var seekChunk = function() {
nthChunk(self, newChunkNumber, function(err, chunk) {
if(err) return callback(err, null);
if(chunk == null) return callback(new Error('no chunk found'));
// Set the current chunk
self.currentChunk = chunk;
self.position = targetPosition;
self.currentChunk.position = (self.position % self.chunkSize);
callback(err, self);
});
};
seekChunk();
}
define.classMethod('seek', {callback: true, promise:true});
/**
* @ignore
*/
var _open = function(self, options, callback) {
var collection = self.collection();
// Create the query
var query = self.referenceBy == REFERENCE_BY_ID ? {_id:self.fileId} : {filename:self.filename};
query = null == self.fileId && self.filename == null ? null : query;
options.readPreference = self.readPreference;
// Fetch the chunks
if(query != null) {
collection.findOne(query, options, function(err, doc) {
if(err) return error(err);
// Check if the collection for the files exists otherwise prepare the new one
if(doc != null) {
self.fileId = doc._id;
// Prefer a new filename over the existing one if this is a write
self.filename = ((self.mode == 'r') || (self.filename == undefined)) ? doc.filename : self.filename;
self.contentType = doc.contentType;
self.internalChunkSize = doc.chunkSize;
self.uploadDate = doc.uploadDate;
self.aliases = doc.aliases;
self.length = doc.length;
self.metadata = doc.metadata;
self.internalMd5 = doc.md5;
} else if (self.mode != 'r') {
self.fileId = self.fileId == null ? new ObjectID() : self.fileId;
self.contentType = GridStore.DEFAULT_CONTENT_TYPE;
self.internalChunkSize = self.internalChunkSize == null ? Chunk.DEFAULT_CHUNK_SIZE : self.internalChunkSize;
self.length = 0;
} else {
self.length = 0;
var txtId = self.fileId._bsontype == "ObjectID" ? self.fileId.toHexString() : self.fileId;
return error(MongoError.create({message: f("file with id %s not opened for writing", (self.referenceBy == REFERENCE_BY_ID ? txtId : self.filename)), driver:true}), self);
}
// Process the mode of the object
if(self.mode == "r") {
nthChunk(self, 0, options, function(err, chunk) {
if(err) return error(err);
self.currentChunk = chunk;
self.position = 0;
callback(null, self);
});
} else if(self.mode == "w" && doc) {
// Delete any existing chunks
deleteChunks(self, options, function(err) {
if(err) return error(err);
self.currentChunk = new Chunk(self, {'n':0}, self.writeConcern);
self.contentType = self.options['content_type'] == null ? self.contentType : self.options['content_type'];
self.internalChunkSize = self.options['chunk_size'] == null ? self.internalChunkSize : self.options['chunk_size'];
self.metadata = self.options['metadata'] == null ? self.metadata : self.options['metadata'];
self.aliases = self.options['aliases'] == null ? self.aliases : self.options['aliases'];
self.position = 0;
callback(null, self);
});
} else if(self.mode == "w") {
self.currentChunk = new Chunk(self, {'n':0}, self.writeConcern);
self.contentType = self.options['content_type'] == null ? self.contentType : self.options['content_type'];
self.internalChunkSize = self.options['chunk_size'] == null ? self.internalChunkSize : self.options['chunk_size'];
self.metadata = self.options['metadata'] == null ? self.metadata : self.options['metadata'];
self.aliases = self.options['aliases'] == null ? self.aliases : self.options['aliases'];
self.position = 0;
callback(null, self);
} else if(self.mode == "w+") {
nthChunk(self, lastChunkNumber(self), options, function(err, chunk) {
if(err) return error(err);
// Set the current chunk
self.currentChunk = chunk == null ? new Chunk(self, {'n':0}, self.writeConcern) : chunk;
self.currentChunk.position = self.currentChunk.data.length();
self.metadata = self.options['metadata'] == null ? self.metadata : self.options['metadata'];
self.aliases = self.options['aliases'] == null ? self.aliases : self.options['aliases'];
self.position = self.length;
callback(null, self);
});
}
});
} else {
// Write only mode
self.fileId = null == self.fileId ? new ObjectID() : self.fileId;
self.contentType = GridStore.DEFAULT_CONTENT_TYPE;
self.internalChunkSize = self.internalChunkSize == null ? Chunk.DEFAULT_CHUNK_SIZE : self.internalChunkSize;
self.length = 0;
// No file exists set up write mode
if(self.mode == "w") {
// Delete any existing chunks
deleteChunks(self, options, function(err) {
if(err) return error(err);
self.currentChunk = new Chunk(self, {'n':0}, self.writeConcern);
self.contentType = self.options['content_type'] == null ? self.contentType : self.options['content_type'];
self.internalChunkSize = self.options['chunk_size'] == null ? self.internalChunkSize : self.options['chunk_size'];
self.metadata = self.options['metadata'] == null ? self.metadata : self.options['metadata'];
self.aliases = self.options['aliases'] == null ? self.aliases : self.options['aliases'];
self.position = 0;
callback(null, self);
});
} else if(self.mode == "w+") {
nthChunk(self, lastChunkNumber(self), options, function(err, chunk) {
if(err) return error(err);
// Set the current chunk
self.currentChunk = chunk == null ? new Chunk(self, {'n':0}, self.writeConcern) : chunk;
self.currentChunk.position = self.currentChunk.data.length();
self.metadata = self.options['metadata'] == null ? self.metadata : self.options['metadata'];
self.aliases = self.options['aliases'] == null ? self.aliases : self.options['aliases'];
self.position = self.length;
callback(null, self);
});
}
}
// only pass error to callback once
function error (err) {
if(error.err) return;
callback(error.err = err);
}
};
/**
* @ignore
*/
var writeBuffer = function(self, buffer, close, callback) {
if(typeof close === "function") { callback = close; close = null; }
var finalClose = typeof close == 'boolean' ? close : false;
if(self.mode != "w") {
callback(MongoError.create({message: f("file with id %s not opened for writing", (self.referenceBy == REFERENCE_BY_ID ? self.referenceBy : self.filename)), driver:true}), null);
} else {
if(self.currentChunk.position + buffer.length >= self.chunkSize) {
// Write out the current Chunk and then keep writing until we have less data left than a chunkSize left
// to a new chunk (recursively)
var previousChunkNumber = self.currentChunk.chunkNumber;
var leftOverDataSize = self.chunkSize - self.currentChunk.position;
var firstChunkData = buffer.slice(0, leftOverDataSize);
var leftOverData = buffer.slice(leftOverDataSize);
// A list of chunks to write out
var chunksToWrite = [self.currentChunk.write(firstChunkData)];
// If we have more data left than the chunk size let's keep writing new chunks
while(leftOverData.length >= self.chunkSize) {
// Create a new chunk and write to it
var newChunk = new Chunk(self, {'n': (previousChunkNumber + 1)}, self.writeConcern);
firstChunkData = leftOverData.slice(0, self.chunkSize);
leftOverData = leftOverData.slice(self.chunkSize);
// Update chunk number
previousChunkNumber = previousChunkNumber + 1;
// Write data
newChunk.write(firstChunkData);
// Push chunk to save list
chunksToWrite.push(newChunk);
}
// Set current chunk with remaining data
self.currentChunk = new Chunk(self, {'n': (previousChunkNumber + 1)}, self.writeConcern);
// If we have left over data write it
if(leftOverData.length > 0) self.currentChunk.write(leftOverData);
// Update the position for the gridstore
self.position = self.position + buffer.length;
// Total number of chunks to write
var numberOfChunksToWrite = chunksToWrite.length;
for(var i = 0; i < chunksToWrite.length; i++) {
chunksToWrite[i].save({}, function(err) {
if(err) return callback(err);
numberOfChunksToWrite = numberOfChunksToWrite - 1;
if(numberOfChunksToWrite <= 0) {
// We care closing the file before returning
if(finalClose) {
return self.close(function(err) {
callback(err, self);
});
}
// Return normally
return callback(null, self);
}
});
}
} else {
// Update the position for the gridstore
self.position = self.position + buffer.length;
// We have less data than the chunk size just write it and callback
self.currentChunk.write(buffer);
// We care closing the file before returning
if(finalClose) {
return self.close(function(err) {
callback(err, self);
});
}
// Return normally
return callback(null, self);
}
}
};
/**
* Creates a mongoDB object representation of this object.
*
* <pre><code>
* {
* '_id' : , // {number} id for this file
* 'filename' : , // {string} name for this file
* 'contentType' : , // {string} mime type for this file
* 'length' : , // {number} size of this file?
* 'chunksize' : , // {number} chunk size used by this file
* 'uploadDate' : , // {Date}
* 'aliases' : , // {array of string}
* 'metadata' : , // {string}
* }
* </code></pre>
*
* @ignore
*/
var buildMongoObject = function(self, callback) {
// Calcuate the length
var mongoObject = {
'_id': self.fileId,
'filename': self.filename,
'contentType': self.contentType,
'length': self.position ? self.position : 0,
'chunkSize': self.chunkSize,
'uploadDate': self.uploadDate,
'aliases': self.aliases,
'metadata': self.metadata
};
var md5Command = {filemd5:self.fileId, root:self.root};
self.db.command(md5Command, function(err, results) {
if(err) return callback(err);
mongoObject.md5 = results.md5;
callback(null, mongoObject);
});
};
/**
* Gets the nth chunk of this file.
* @ignore
*/
var nthChunk = function(self, chunkNumber, options, callback) {
if(typeof options == 'function') {
callback = options;
options = {};
}
options = options || self.writeConcern;
options.readPreference = self.readPreference;
// Get the nth chunk
self.chunkCollection().findOne({'files_id':self.fileId, 'n':chunkNumber}, options, function(err, chunk) {
if(err) return callback(err);
var finalChunk = chunk == null ? {} : chunk;
callback(null, new Chunk(self, finalChunk, self.writeConcern));
});
};
/**
* @ignore
*/
var lastChunkNumber = function(self) {
return Math.floor((self.length ? self.length - 1 : 0)/self.chunkSize);
};
/**
* Deletes all the chunks of this file in the database.
*
* @ignore
*/
var deleteChunks = function(self, options, callback) {
if(typeof options == 'function') {
callback = options;
options = {};
}
options = options || self.writeConcern;
if(self.fileId != null) {
self.chunkCollection().remove({'files_id':self.fileId}, options, function(err) {
if(err) return callback(err, false);
callback(null, true);
});
} else {
callback(null, true);
}
};
/**
* The collection to be used for holding the files and chunks collection.
*
* @classconstant DEFAULT_ROOT_COLLECTION
**/
GridStore.DEFAULT_ROOT_COLLECTION = 'fs';
/**
* Default file mime type
*
* @classconstant DEFAULT_CONTENT_TYPE
**/
GridStore.DEFAULT_CONTENT_TYPE = 'binary/octet-stream';
/**
* Seek mode where the given length is absolute.
*
* @classconstant IO_SEEK_SET
**/
GridStore.IO_SEEK_SET = 0;
/**
* Seek mode where the given length is an offset to the current read/write head.
*
* @classconstant IO_SEEK_CUR
**/
GridStore.IO_SEEK_CUR = 1;
/**
* Seek mode where the given length is an offset to the end of the file.
*
* @classconstant IO_SEEK_END
**/
GridStore.IO_SEEK_END = 2;
/**
* Checks if a file exists in the database.
*
* @method
* @static
* @param {Db} db the database to query.
* @param {string} name The name of the file to look for.
* @param {string} [rootCollection] The root collection that holds the files and chunks collection. Defaults to **{GridStore.DEFAULT_ROOT_COLLECTION}**.
* @param {object} [options=null] Optional settings.
* @param {(ReadPreference|string)} [options.readPreference=null] The preferred read preference (ReadPreference.PRIMARY, ReadPreference.PRIMARY_PREFERRED, ReadPreference.SECONDARY, ReadPreference.SECONDARY_PREFERRED, ReadPreference.NEAREST).
* @param {object} [options.promiseLibrary=null] A Promise library class the application wishes to use such as Bluebird, must be ES6 compatible
* @param {GridStore~resultCallback} [callback] result from exists.
* @return {Promise} returns Promise if no callback passed
* @deprecated Use GridFSBucket API instead
*/
GridStore.exist = function(db, fileIdObject, rootCollection, options, callback) {
var args = Array.prototype.slice.call(arguments, 2);
callback = args.pop();
if(typeof callback != 'function') args.push(callback);
rootCollection = args.length ? args.shift() : null;
options = args.length ? args.shift() : {};
options = options || {};
// Get the promiseLibrary
var promiseLibrary = options.promiseLibrary;
// No promise library selected fall back
if(!promiseLibrary) {
promiseLibrary = typeof global.Promise == 'function' ?
global.Promise : require('es6-promise').Promise;
}
// We provided a callback leg
if(typeof callback == 'function') return exists(db, fileIdObject, rootCollection, options, callback);
// Return promise
return new promiseLibrary(function(resolve, reject) {
exists(db, fileIdObject, rootCollection, options, function(err, r) {
if(err) return reject(err);
resolve(r);
})
});
};
var exists = function(db, fileIdObject, rootCollection, options, callback) {
// Establish read preference
var readPreference = options.readPreference || ReadPreference.PRIMARY;
// Fetch collection
var rootCollectionFinal = rootCollection != null ? rootCollection : GridStore.DEFAULT_ROOT_COLLECTION;
db.collection(rootCollectionFinal + ".files", function(err, collection) {
if(err) return callback(err);
// Build query
var query = (typeof fileIdObject == 'string' || Object.prototype.toString.call(fileIdObject) == '[object RegExp]' )
? {'filename':fileIdObject}
: {'_id':fileIdObject}; // Attempt to locate file
// We have a specific query
if(fileIdObject != null
&& typeof fileIdObject == 'object'
&& Object.prototype.toString.call(fileIdObject) != '[object RegExp]') {
query = fileIdObject;
}
// Check if the entry exists
collection.findOne(query, {readPreference:readPreference}, function(err, item) {
if(err) return callback(err);
callback(null, item == null ? false : true);
});
});
}
define.staticMethod('exist', {callback: true, promise:true});
/**
* Gets the list of files stored in the GridFS.
*
* @method
* @static
* @param {Db} db the database to query.
* @param {string} [rootCollection] The root collection that holds the files and chunks collection. Defaults to **{GridStore.DEFAULT_ROOT_COLLECTION}**.
* @param {object} [options=null] Optional settings.
* @param {(ReadPreference|string)} [options.readPreference=null] The preferred read preference (ReadPreference.PRIMARY, ReadPreference.PRIMARY_PREFERRED, ReadPreference.SECONDARY, ReadPreference.SECONDARY_PREFERRED, ReadPreference.NEAREST).
* @param {object} [options.promiseLibrary=null] A Promise library class the application wishes to use such as Bluebird, must be ES6 compatible
* @param {GridStore~resultCallback} [callback] result from exists.
* @return {Promise} returns Promise if no callback passed
* @deprecated Use GridFSBucket API instead
*/
GridStore.list = function(db, rootCollection, options, callback) {
var args = Array.prototype.slice.call(arguments, 1);
callback = args.pop();
if(typeof callback != 'function') args.push(callback);
rootCollection = args.length ? args.shift() : null;
options = args.length ? args.shift() : {};
options = options || {};
// Get the promiseLibrary
var promiseLibrary = options.promiseLibrary;
// No promise library selected fall back
if(!promiseLibrary) {
promiseLibrary = typeof global.Promise == 'function' ?
global.Promise : require('es6-promise').Promise;
}
// We provided a callback leg
if(typeof callback == 'function') return list(db, rootCollection, options, callback);
// Return promise
return new promiseLibrary(function(resolve, reject) {
list(db, rootCollection, options, function(err, r) {
if(err) return reject(err);
resolve(r);
})
});
};
var list = function(db, rootCollection, options, callback) {
// Ensure we have correct values
if(rootCollection != null && typeof rootCollection == 'object') {
options = rootCollection;
rootCollection = null;
}
// Establish read preference
var readPreference = options.readPreference || ReadPreference.PRIMARY;
// Check if we are returning by id not filename
var byId = options['id'] != null ? options['id'] : false;
// Fetch item
var rootCollectionFinal = rootCollection != null ? rootCollection : GridStore.DEFAULT_ROOT_COLLECTION;
var items = [];
db.collection((rootCollectionFinal + ".files"), function(err, collection) {
if(err) return callback(err);
collection.find({}, {readPreference:readPreference}, function(err, cursor) {
if(err) return callback(err);
cursor.each(function(err, item) {
if(item != null) {
items.push(byId ? item._id : item.filename);
}