'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 here. * * @example * const MongoClient = require('mongodb').MongoClient; * const GridStore = require('mongodb').GridStore; * const ObjectID = require('mongodb').ObjectID; * const test = require('assert'); * // Connection url * const url = 'mongodb://localhost:27017'; * // Database Name * const dbName = 'test'; * // Connect using MongoClient * MongoClient.connect(url, function(err, client) { * const db = client.db(dbName); * const 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); * client.close(); * test.done(); * }); * }); * }); * }); * }); */ const Chunk = require('./chunk'); const ObjectID = require('../core').BSON.ObjectID; const ReadPreference = require('../core').ReadPreference; const Buffer = require('safe-buffer').Buffer; const fs = require('fs'); const f = require('util').format; const util = require('util'); const MongoError = require('../core').MongoError; const inherits = util.inherits; const Duplex = require('stream').Duplex; const shallowClone = require('../utils').shallowClone; const executeLegacyOperation = require('../utils').executeLegacyOperation; const deprecate = require('util').deprecate; var REFERENCE_BY_FILENAME = 0, REFERENCE_BY_ID = 1; const deprecationFn = deprecate(() => {}, 'GridStore is deprecated, and will be removed in a future version. Please use GridFSBucket instead'); /** * Namespace provided by the core module * @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 overwritten. * * @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] Optional settings. * @param {(number|string)} [options.w] The write concern. * @param {number} [options.wtimeout] 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] Root collection to use. Defaults to **{GridStore.DEFAULT_ROOT_COLLECTION}**. * @param {string} [options.content_type] 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] Arbitrary data the user wants to store. * @param {object} [options.promiseLibrary] A Promise library class the application wishes to use such as Bluebird, must be ES6 compatible * @param {(ReadPreference|string)} [options.readPreference] 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) { deprecationFn(); 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 || 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; } }); }; /** * 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 {object} [options] Optional settings * @param {ClientSession} [options.session] optional session to use for this operation * @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(options, callback) { if (typeof options === 'function') (callback = options), (options = {}); options = options || {}; if (this.mode !== 'w' && this.mode !== 'w+' && this.mode !== 'r') { throw MongoError.create({ message: 'Illegal mode ' + this.mode, driver: true }); } return executeLegacyOperation(this.db.s.topology, open, [this, options, callback], { skipSessions: true }); }; var open = function(self, options, 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); }); } }; /** * 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; }; /** * The callback result format. * @callback GridStore~resultCallback * @param {object} [options] Optional settings * @param {ClientSession} [options.session] optional session to use for this operation * @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(options, callback) { if (typeof options === 'function') (callback = options), (options = {}); options = options || {}; return executeLegacyOperation(this.db.s.topology, getc, [this, options, callback], { skipSessions: true }); }; var getc = function(self, options, 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()); } }; /** * 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 {object} [options] Optional settings * @param {ClientSession} [options.session] optional session to use for this operation * @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, options, callback) { if (typeof options === 'function') (callback = options), (options = {}); options = options || {}; var finalString = string.match(/\n$/) == null ? string + '\n' : string; return executeLegacyOperation( this.db.s.topology, this.write.bind(this), [finalString, options, callback], { skipSessions: 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); }; /** * 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 {object} [options] Optional settings * @param {ClientSession} [options.session] optional session to use for this operation * @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, options, callback) { if (typeof options === 'function') (callback = options), (options = {}); options = options || {}; return executeLegacyOperation( this.db.s.topology, _writeNormal, [this, data, close, options, callback], { skipSessions: 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'); } }; /** * Stores a file from the file system to the GridFS database. * * @method * @param {(string|Buffer|FileHandle)} file the file to store. * @param {object} [options] Optional settings * @param {ClientSession} [options.session] optional session to use for this operation * @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, options, callback) { if (typeof options === 'function') (callback = options), (options = {}); options = options || {}; return executeLegacyOperation(this.db.s.topology, writeFile, [this, file, options, callback], { skipSessions: true }); }; var writeFile = function(self, file, options, 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() { // Allocate the buffer var _buffer = Buffer.alloc(self.chunkSize); // Read the file fs.read(file, _buffer, 0, _buffer.length, offset, function(err, bytesRead, data) { 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.slice(0, bytesRead), function(err, chunk) { if (err) return callback(err, self); chunk.save({}, function(err) { if (err) return callback(err, self); self.position = self.position + bytesRead; // Point to current chunk self.currentChunk = chunk; if (offset >= stats.size) { fs.close(file, function(err) { if (err) return callback(err); 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); }); }); }; /** * 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 {object} [options] Optional settings * @param {ClientSession} [options.session] optional session to use for this operation * @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(options, callback) { if (typeof options === 'function') (callback = options), (options = {}); options = options || {}; return executeLegacyOperation(this.db.s.topology, close, [this, options, callback], { skipSessions: true }); }; var close = function(self, options, callback) { if (self.mode[0] === 'w') { // Set up options options = Object.assign({}, self.writeConcern, options); 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 })); } }; /** * 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'); }; /** * Deletes all the chunks of this file in the database. * * @method * @param {object} [options] Optional settings * @param {ClientSession} [options.session] optional session to use for this operation * @param {GridStore~resultCallback} [callback] the command callback. * @return {Promise} returns Promise if no callback passed * @deprecated Use GridFSBucket API instead */ GridStore.prototype.unlink = function(options, callback) { if (typeof options === 'function') (callback = options), (options = {}); options = options || {}; return executeLegacyOperation(this.db.s.topology, unlink, [this, options, callback], { skipSessions: true }); }; var unlink = function(self, options, 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); }); }); }); }; /** * 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'); }; /** * 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 {object} [options] Optional settings * @param {ClientSession} [options.session] optional session to use for this operation * @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, options, callback) { var args = Array.prototype.slice.call(arguments, 0); callback = typeof args[args.length - 1] === 'function' ? args.pop() : undefined; separator = args.length ? args.shift() : '\n'; separator = separator || '\n'; options = args.length ? args.shift() : {}; return executeLegacyOperation( this.db.s.topology, readlines, [this, separator, options, callback], { skipSessions: true } ); }; var readlines = function(self, separator, options, 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); }); }; /** * 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 {object} [options] Optional settings * @param {ClientSession} [options.session] optional session to use for this operation * @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(options, callback) { if (typeof options === 'function') (callback = options), (options = {}); options = options || {}; return executeLegacyOperation(this.db.s.topology, rewind, [this, options, callback], { skipSessions: true }); }; var rewind = function(self, options, 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); } }; /** * 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 {object} [options] Optional settings * @param {ClientSession} [options.session] optional session to use for this operation * @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, options, callback) { var args = Array.prototype.slice.call(arguments, 0); callback = typeof args[args.length - 1] === 'function' ? args.pop() : undefined; length = args.length ? args.shift() : null; buffer = args.length ? args.shift() : null; options = args.length ? args.shift() : {}; return executeLegacyOperation( this.db.s.topology, read, [this, length, buffer, options, callback], { skipSessions: true } ); }; var read = function(self, length, buffer, options, 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 ? Buffer.alloc(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 ); } } }); }; /** * 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 {object} [options] Optional settings * @param {ClientSession} [options.session] optional session to use for this operation * @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); }); }; /** * 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 {object} [options] Optional settings * @param {ClientSession} [options.session] optional session to use for this operation * @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, options, callback) { var args = Array.prototype.slice.call(arguments, 1); callback = typeof args[args.length - 1] === 'function' ? args.pop() : undefined; seekLocation = args.length ? args.shift() : null; options = args.length ? args.shift() : {}; return executeLegacyOperation( this.db.s.topology, seek, [this, position, seekLocation, options, callback], { skipSessions: true } ); }; var seek = function(self, position, seekLocation, options, 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(); }; /** * @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. * *

 *        {
 *          '_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}
 *        }
 *        
* * @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] Optional settings. * @param {(ReadPreference|string)} [options.readPreference] The preferred read preference (ReadPreference.PRIMARY, ReadPreference.PRIMARY_PREFERRED, ReadPreference.SECONDARY, ReadPreference.SECONDARY_PREFERRED, ReadPreference.NEAREST). * @param {object} [options.promiseLibrary] A Promise library class the application wishes to use such as Bluebird, must be ES6 compatible * @param {ClientSession} [options.session] optional session to use for this operation * @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 = typeof args[args.length - 1] === 'function' ? args.pop() : undefined; rootCollection = args.length ? args.shift() : null; options = args.length ? args.shift() : {}; options = options || {}; return executeLegacyOperation( db.s.topology, exists, [db, fileIdObject, rootCollection, options, callback], { skipSessions: true } ); }; 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); }); }); }; /** * 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] Optional settings. * @param {(ReadPreference|string)} [options.readPreference] The preferred read preference (ReadPreference.PRIMARY, ReadPreference.PRIMARY_PREFERRED, ReadPreference.SECONDARY, ReadPreference.SECONDARY_PREFERRED, ReadPreference.NEAREST). * @param {object} [options.promiseLibrary] A Promise library class the application wishes to use such as Bluebird, must be ES6 compatible * @param {ClientSession} [options.session] optional session to use for this operation * @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 = typeof args[args.length - 1] === 'function' ? args.pop() : undefined; rootCollection = args.length ? args.shift() : null; options = args.length ? args.shift() : {}; options = options || {}; return executeLegacyOperation(db.s.topology, list, [db, rootCollection, options, callback], { skipSessions: true }); }; 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); } else { callback(err, items); } }); }); }); }; /** * Reads the contents of a file. * * This method has the following signatures * * (db, name, callback) * (db, name, length, callback) * (db, name, length, offset, callback) * (db, name, length, offset, options, callback) * * @method * @static * @param {Db} db the database to query. * @param {string} name The name of the file. * @param {number} [length] The size of data to read. * @param {number} [offset] The offset from the head of the file of which to start reading from. * @param {object} [options] Optional settings. * @param {(ReadPreference|string)} [options.readPreference] The preferred read preference (ReadPreference.PRIMARY, ReadPreference.PRIMARY_PREFERRED, ReadPreference.SECONDARY, ReadPreference.SECONDARY_PREFERRED, ReadPreference.NEAREST). * @param {object} [options.promiseLibrary] A Promise library class the application wishes to use such as Bluebird, must be ES6 compatible * @param {ClientSession} [options.session] optional session to use for this operation * @param {GridStore~readCallback} [callback] the command callback. * @return {Promise} returns Promise if no callback passed * @deprecated Use GridFSBucket API instead */ GridStore.read = function(db, name, length, offset, options, callback) { var args = Array.prototype.slice.call(arguments, 2); callback = typeof args[args.length - 1] === 'function' ? args.pop() : undefined; length = args.length ? args.shift() : null; offset = args.length ? args.shift() : null; options = args.length ? args.shift() : null; options = options || {}; return executeLegacyOperation( db.s.topology, readStatic, [db, name, length, offset, options, callback], { skipSessions: true } ); }; var readStatic = function(db, name, length, offset, options, callback) { new GridStore(db, name, 'r', options).open(function(err, gridStore) { if (err) return callback(err); // Make sure we are not reading out of bounds if (offset && offset >= gridStore.length) return callback('offset larger than size of file', null); if (length && length > gridStore.length) return callback('length is larger than the size of the file', null); if (offset && length && offset + length > gridStore.length) return callback('offset and length is larger than the size of the file', null); if (offset != null) { gridStore.seek(offset, function(err, gridStore) { if (err) return callback(err); gridStore.read(length, callback); }); } else { gridStore.read(length, callback); } }); }; /** * Read the entire file as a list of strings splitting by the provided separator. * * @method * @static * @param {Db} db the database to query. * @param {(String|object)} name the name of the file. * @param {string} [separator] The character to be recognized as the newline separator. * @param {object} [options] Optional settings. * @param {(ReadPreference|string)} [options.readPreference] The preferred read preference (ReadPreference.PRIMARY, ReadPreference.PRIMARY_PREFERRED, ReadPreference.SECONDARY, ReadPreference.SECONDARY_PREFERRED, ReadPreference.NEAREST). * @param {object} [options.promiseLibrary] A Promise library class the application wishes to use such as Bluebird, must be ES6 compatible * @param {ClientSession} [options.session] optional session to use for this operation * @param {GridStore~readlinesCallback} [callback] the command callback. * @return {Promise} returns Promise if no callback passed * @deprecated Use GridFSBucket API instead */ GridStore.readlines = function(db, name, separator, options, callback) { var args = Array.prototype.slice.call(arguments, 2); callback = typeof args[args.length - 1] === 'function' ? args.pop() : undefined; separator = args.length ? args.shift() : null; options = args.length ? args.shift() : null; options = options || {}; return executeLegacyOperation( db.s.topology, readlinesStatic, [db, name, separator, options, callback], { skipSessions: true } ); }; var readlinesStatic = function(db, name, separator, options, callback) { var finalSeperator = separator == null ? '\n' : separator; new GridStore(db, name, 'r', options).open(function(err, gridStore) { if (err) return callback(err); gridStore.readlines(finalSeperator, callback); }); }; /** * Deletes the chunks and metadata information of a file from GridFS. * * @method * @static * @param {Db} db The database to query. * @param {(string|array)} names The name/names of the files to delete. * @param {object} [options] Optional settings. * @param {object} [options.promiseLibrary] A Promise library class the application wishes to use such as Bluebird, must be ES6 compatible * @param {ClientSession} [options.session] optional session to use for this operation * @param {GridStore~resultCallback} [callback] the command callback. * @return {Promise} returns Promise if no callback passed * @deprecated Use GridFSBucket API instead */ GridStore.unlink = function(db, names, options, callback) { var args = Array.prototype.slice.call(arguments, 2); callback = typeof args[args.length - 1] === 'function' ? args.pop() : undefined; options = args.length ? args.shift() : {}; options = options || {}; return executeLegacyOperation(db.s.topology, unlinkStatic, [this, db, names, options, callback], { skipSessions: true }); }; var unlinkStatic = function(self, db, names, options, callback) { // Get the write concern var writeConcern = _getWriteConcern(db, options); // List of names if (names.constructor === Array) { var tc = 0; for (var i = 0; i < names.length; i++) { ++tc; GridStore.unlink(db, names[i], options, function() { if (--tc === 0) { callback(null, self); } }); } } else { new GridStore(db, names, 'w', options).open(function(err, gridStore) { if (err) return callback(err); deleteChunks(gridStore, function(err) { if (err) return callback(err); gridStore.collection(function(err, collection) { if (err) return callback(err); collection.remove({ _id: gridStore.fileId }, writeConcern, function(err) { callback(err, self); }); }); }); }); } }; /** * @ignore */ var _writeNormal = function(self, data, close, options, callback) { // If we have a buffer write it using the writeBuffer method if (Buffer.isBuffer(data)) { return writeBuffer(self, data, close, callback); } else { return writeBuffer(self, Buffer.from(data, 'binary'), close, callback); } }; /** * @ignore */ var _setWriteConcernHash = function(options) { var finalOptions = {}; if (options.w != null) finalOptions.w = options.w; if (options.journal === true) finalOptions.j = options.journal; if (options.j === true) finalOptions.j = options.j; if (options.fsync === true) finalOptions.fsync = options.fsync; if (options.wtimeout != null) finalOptions.wtimeout = options.wtimeout; return finalOptions; }; /** * @ignore */ var _getWriteConcern = function(self, options) { // Final options var finalOptions = { w: 1 }; options = options || {}; // Local options verification if ( options.w != null || typeof options.j === 'boolean' || typeof options.journal === 'boolean' || typeof options.fsync === 'boolean' ) { finalOptions = _setWriteConcernHash(options); } else if (options.safe != null && typeof options.safe === 'object') { finalOptions = _setWriteConcernHash(options.safe); } else if (typeof options.safe === 'boolean') { finalOptions = { w: options.safe ? 1 : 0 }; } else if ( self.options.w != null || typeof self.options.j === 'boolean' || typeof self.options.journal === 'boolean' || typeof self.options.fsync === 'boolean' ) { finalOptions = _setWriteConcernHash(self.options); } else if ( self.safe && (self.safe.w != null || typeof self.safe.j === 'boolean' || typeof self.safe.journal === 'boolean' || typeof self.safe.fsync === 'boolean') ) { finalOptions = _setWriteConcernHash(self.safe); } else if (typeof self.safe === 'boolean') { finalOptions = { w: self.safe ? 1 : 0 }; } // Ensure we don't have an invalid combination of write concerns if ( finalOptions.w < 1 && (finalOptions.journal === true || finalOptions.j === true || finalOptions.fsync === true) ) throw MongoError.create({ message: 'No acknowledgement using w < 1 cannot be combined with journal:true or fsync:true', driver: true }); // Return the options return finalOptions; }; /** * Create a new GridStoreStream instance (INTERNAL TYPE, do not instantiate directly) * * @class * @extends external:Duplex * @return {GridStoreStream} a GridStoreStream instance. * @deprecated Use GridFSBucket API instead */ var GridStoreStream = function(gs) { // Initialize the duplex stream Duplex.call(this); // Get the gridstore this.gs = gs; // End called this.endCalled = false; // If we have a seek this.totalBytesToRead = this.gs.length - this.gs.position; this.seekPosition = this.gs.position; }; // // Inherit duplex inherits(GridStoreStream, Duplex); GridStoreStream.prototype._pipe = GridStoreStream.prototype.pipe; // Set up override GridStoreStream.prototype.pipe = function(destination) { var self = this; // Only open gridstore if not already open if (!self.gs.isOpen) { self.gs.open(function(err) { if (err) return self.emit('error', err); self.totalBytesToRead = self.gs.length - self.gs.position; self._pipe.apply(self, [destination]); }); } else { self.totalBytesToRead = self.gs.length - self.gs.position; self._pipe.apply(self, [destination]); } return destination; }; // Called by stream GridStoreStream.prototype._read = function() { var self = this; var read = function() { // Read data self.gs.read(length, function(err, buffer) { if (err && !self.endCalled) return self.emit('error', err); // Stream is closed if (self.endCalled || buffer == null) return self.push(null); // Remove bytes read if (buffer.length <= self.totalBytesToRead) { self.totalBytesToRead = self.totalBytesToRead - buffer.length; self.push(buffer); } else if (buffer.length > self.totalBytesToRead) { self.totalBytesToRead = self.totalBytesToRead - buffer._index; self.push(buffer.slice(0, buffer._index)); } // Finished reading if (self.totalBytesToRead <= 0) { self.endCalled = true; } }); }; // Set read length var length = self.gs.length < self.gs.chunkSize ? self.gs.length - self.seekPosition : self.gs.chunkSize; if (!self.gs.isOpen) { self.gs.open(function(err) { self.totalBytesToRead = self.gs.length - self.gs.position; if (err) return self.emit('error', err); read(); }); } else { read(); } }; GridStoreStream.prototype.destroy = function() { this.pause(); this.endCalled = true; this.gs.close(); this.emit('end'); }; GridStoreStream.prototype.write = function(chunk) { var self = this; if (self.endCalled) return self.emit( 'error', MongoError.create({ message: 'attempting to write to stream after end called', driver: true }) ); // Do we have to open the gridstore if (!self.gs.isOpen) { self.gs.open(function() { self.gs.isOpen = true; self.gs.write(chunk, function() { process.nextTick(function() { self.emit('drain'); }); }); }); return false; } else { self.gs.write(chunk, function() { self.emit('drain'); }); return true; } }; GridStoreStream.prototype.end = function(chunk, encoding, callback) { var self = this; var args = Array.prototype.slice.call(arguments, 0); callback = typeof args[args.length - 1] === 'function' ? args.pop() : undefined; chunk = args.length ? args.shift() : null; encoding = args.length ? args.shift() : null; self.endCalled = true; if (chunk) { self.gs.write(chunk, function() { self.gs.close(function() { if (typeof callback === 'function') callback(); self.emit('end'); }); }); } self.gs.close(function() { if (typeof callback === 'function') callback(); self.emit('end'); }); }; /** * The read() method pulls some data out of the internal buffer and returns it. If there is no data available, then it will return null. * @function external:Duplex#read * @param {number} size Optional argument to specify how much data to read. * @return {(String | Buffer | null)} */ /** * Call this function to cause the stream to return strings of the specified encoding instead of Buffer objects. * @function external:Duplex#setEncoding * @param {string} encoding The encoding to use. * @return {null} */ /** * This method will cause the readable stream to resume emitting data events. * @function external:Duplex#resume * @return {null} */ /** * This method will cause a stream in flowing-mode to stop emitting data events. Any data that becomes available will remain in the internal buffer. * @function external:Duplex#pause * @return {null} */ /** * This method pulls all the data out of a readable stream, and writes it to the supplied destination, automatically managing the flow so that the destination is not overwhelmed by a fast readable stream. * @function external:Duplex#pipe * @param {Writable} destination The destination for writing data * @param {object} [options] Pipe options * @return {null} */ /** * This method will remove the hooks set up for a previous pipe() call. * @function external:Duplex#unpipe * @param {Writable} [destination] The destination for writing data * @return {null} */ /** * This is useful in certain cases where a stream is being consumed by a parser, which needs to "un-consume" some data that it has optimistically pulled out of the source, so that the stream can be passed on to some other party. * @function external:Duplex#unshift * @param {(Buffer|string)} chunk Chunk of data to unshift onto the read queue. * @return {null} */ /** * Versions of Node prior to v0.10 had streams that did not implement the entire Streams API as it is today. (See "Compatibility" below for more information.) * @function external:Duplex#wrap * @param {Stream} stream An "old style" readable stream. * @return {null} */ /** * This method writes some data to the underlying system, and calls the supplied callback once the data has been fully handled. * @function external:Duplex#write * @param {(string|Buffer)} chunk The data to write * @param {string} encoding The encoding, if chunk is a String * @param {function} callback Callback for when this chunk of data is flushed * @return {boolean} */ /** * Call this method when no more data will be written to the stream. If supplied, the callback is attached as a listener on the finish event. * @function external:Duplex#end * @param {(string|Buffer)} chunk The data to write * @param {string} encoding The encoding, if chunk is a String * @param {function} callback Callback for when this chunk of data is flushed * @return {null} */ /** * GridStoreStream stream data event, fired for each document in the cursor. * * @event GridStoreStream#data * @type {object} */ /** * GridStoreStream stream end event * * @event GridStoreStream#end * @type {null} */ /** * GridStoreStream stream close event * * @event GridStoreStream#close * @type {null} */ /** * GridStoreStream stream readable event * * @event GridStoreStream#readable * @type {null} */ /** * GridStoreStream stream drain event * * @event GridStoreStream#drain * @type {null} */ /** * GridStoreStream stream finish event * * @event GridStoreStream#finish * @type {null} */ /** * GridStoreStream stream pipe event * * @event GridStoreStream#pipe * @type {null} */ /** * GridStoreStream stream unpipe event * * @event GridStoreStream#unpipe * @type {null} */ /** * GridStoreStream stream error event * * @event GridStoreStream#error * @type {null} */ /** * @ignore */ module.exports = GridStore;