Initial commit

node_modules/mongodb/lib/core/connection/apm.js

@@ -0,0 +1,251 @@
+'use strict';
+const Msg = require('../connection/msg').Msg;
+const KillCursor = require('../connection/commands').KillCursor;
+const GetMore = require('../connection/commands').GetMore;
+const calculateDurationInMs = require('../../utils').calculateDurationInMs;
+
+/** Commands that we want to redact because of the sensitive nature of their contents */
+const SENSITIVE_COMMANDS = new Set([
+  'authenticate',
+  'saslStart',
+  'saslContinue',
+  'getnonce',
+  'createUser',
+  'updateUser',
+  'copydbgetnonce',
+  'copydbsaslstart',
+  'copydb'
+]);
+
+// helper methods
+const extractCommandName = commandDoc => Object.keys(commandDoc)[0];
+const namespace = command => command.ns;
+const databaseName = command => command.ns.split('.')[0];
+const collectionName = command => command.ns.split('.')[1];
+const generateConnectionId = pool =>
+  pool.options ? `${pool.options.host}:${pool.options.port}` : pool.address;
+const maybeRedact = (commandName, result) => (SENSITIVE_COMMANDS.has(commandName) ? {} : result);
+const isLegacyPool = pool => pool.s && pool.queue;
+
+const LEGACY_FIND_QUERY_MAP = {
+  $query: 'filter',
+  $orderby: 'sort',
+  $hint: 'hint',
+  $comment: 'comment',
+  $maxScan: 'maxScan',
+  $max: 'max',
+  $min: 'min',
+  $returnKey: 'returnKey',
+  $showDiskLoc: 'showRecordId',
+  $maxTimeMS: 'maxTimeMS',
+  $snapshot: 'snapshot'
+};
+
+const LEGACY_FIND_OPTIONS_MAP = {
+  numberToSkip: 'skip',
+  numberToReturn: 'batchSize',
+  returnFieldsSelector: 'projection'
+};
+
+const OP_QUERY_KEYS = [
+  'tailable',
+  'oplogReplay',
+  'noCursorTimeout',
+  'awaitData',
+  'partial',
+  'exhaust'
+];
+
+/**
+ * Extract the actual command from the query, possibly upconverting if it's a legacy
+ * format
+ *
+ * @param {Object} command the command
+ */
+const extractCommand = command => {
+  if (command instanceof GetMore) {
+    return {
+      getMore: command.cursorId,
+      collection: collectionName(command),
+      batchSize: command.numberToReturn
+    };
+  }
+
+  if (command instanceof KillCursor) {
+    return {
+      killCursors: collectionName(command),
+      cursors: command.cursorIds
+    };
+  }
+
+  if (command instanceof Msg) {
+    return command.command;
+  }
+
+  if (command.query && command.query.$query) {
+    let result;
+    if (command.ns === 'admin.$cmd') {
+      // upconvert legacy command
+      result = Object.assign({}, command.query.$query);
+    } else {
+      // upconvert legacy find command
+      result = { find: collectionName(command) };
+      Object.keys(LEGACY_FIND_QUERY_MAP).forEach(key => {
+        if (typeof command.query[key] !== 'undefined')
+          result[LEGACY_FIND_QUERY_MAP[key]] = command.query[key];
+      });
+    }
+
+    Object.keys(LEGACY_FIND_OPTIONS_MAP).forEach(key => {
+      if (typeof command[key] !== 'undefined') result[LEGACY_FIND_OPTIONS_MAP[key]] = command[key];
+    });
+
+    OP_QUERY_KEYS.forEach(key => {
+      if (command[key]) result[key] = command[key];
+    });
+
+    if (typeof command.pre32Limit !== 'undefined') {
+      result.limit = command.pre32Limit;
+    }
+
+    if (command.query.$explain) {
+      return { explain: result };
+    }
+
+    return result;
+  }
+
+  return command.query ? command.query : command;
+};
+
+const extractReply = (command, reply) => {
+  if (command instanceof GetMore) {
+    return {
+      ok: 1,
+      cursor: {
+        id: reply.message.cursorId,
+        ns: namespace(command),
+        nextBatch: reply.message.documents
+      }
+    };
+  }
+
+  if (command instanceof KillCursor) {
+    return {
+      ok: 1,
+      cursorsUnknown: command.cursorIds
+    };
+  }
+
+  // is this a legacy find command?
+  if (command.query && typeof command.query.$query !== 'undefined') {
+    return {
+      ok: 1,
+      cursor: {
+        id: reply.message.cursorId,
+        ns: namespace(command),
+        firstBatch: reply.message.documents
+      }
+    };
+  }
+
+  return reply && reply.result ? reply.result : reply;
+};
+
+const extractConnectionDetails = pool => {
+  if (isLegacyPool(pool)) {
+    return {
+      connectionId: generateConnectionId(pool)
+    };
+  }
+
+  // APM in the modern pool is done at the `Connection` level, so we rename it here for
+  // readability.
+  const connection = pool;
+  return {
+    address: connection.address,
+    connectionId: connection.id
+  };
+};
+
+/** An event indicating the start of a given command */
+class CommandStartedEvent {
+  /**
+   * Create a started event
+   *
+   * @param {Pool} pool the pool that originated the command
+   * @param {Object} command the command
+   */
+  constructor(pool, command) {
+    const cmd = extractCommand(command);
+    const commandName = extractCommandName(cmd);
+    const connectionDetails = extractConnectionDetails(pool);
+
+    // NOTE: remove in major revision, this is not spec behavior
+    if (SENSITIVE_COMMANDS.has(commandName)) {
+      this.commandObj = {};
+      this.commandObj[commandName] = true;
+    }
+
+    Object.assign(this, connectionDetails, {
+      requestId: command.requestId,
+      databaseName: databaseName(command),
+      commandName,
+      command: cmd
+    });
+  }
+}
+
+/** An event indicating the success of a given command */
+class CommandSucceededEvent {
+  /**
+   * Create a succeeded event
+   *
+   * @param {Pool} pool the pool that originated the command
+   * @param {Object} command the command
+   * @param {Object} reply the reply for this command from the server
+   * @param {Array} started a high resolution tuple timestamp of when the command was first sent, to calculate duration
+   */
+  constructor(pool, command, reply, started) {
+    const cmd = extractCommand(command);
+    const commandName = extractCommandName(cmd);
+    const connectionDetails = extractConnectionDetails(pool);
+
+    Object.assign(this, connectionDetails, {
+      requestId: command.requestId,
+      commandName,
+      duration: calculateDurationInMs(started),
+      reply: maybeRedact(commandName, extractReply(command, reply))
+    });
+  }
+}
+
+/** An event indicating the failure of a given command */
+class CommandFailedEvent {
+  /**
+   * Create a failure event
+   *
+   * @param {Pool} pool the pool that originated the command
+   * @param {Object} command the command
+   * @param {MongoError|Object} error the generated error or a server error response
+   * @param {Array} started a high resolution tuple timestamp of when the command was first sent, to calculate duration
+   */
+  constructor(pool, command, error, started) {
+    const cmd = extractCommand(command);
+    const commandName = extractCommandName(cmd);
+    const connectionDetails = extractConnectionDetails(pool);
+
+    Object.assign(this, connectionDetails, {
+      requestId: command.requestId,
+      commandName,
+      duration: calculateDurationInMs(started),
+      failure: maybeRedact(commandName, error)
+    });
+  }
+}
+
+module.exports = {
+  CommandStartedEvent,
+  CommandSucceededEvent,
+  CommandFailedEvent
+};

node_modules/mongodb/lib/core/connection/command_result.js

@@ -0,0 +1,36 @@
+'use strict';
+
+/**
+ * Creates a new CommandResult instance
+ * @class
+ * @param {object} result CommandResult object
+ * @param {Connection} connection A connection instance associated with this result
+ * @return {CommandResult} A cursor instance
+ */
+var CommandResult = function(result, connection, message) {
+  this.result = result;
+  this.connection = connection;
+  this.message = message;
+};
+
+/**
+ * Convert CommandResult to JSON
+ * @method
+ * @return {object}
+ */
+CommandResult.prototype.toJSON = function() {
+  let result = Object.assign({}, this, this.result);
+  delete result.message;
+  return result;
+};
+
+/**
+ * Convert CommandResult to String representation
+ * @method
+ * @return {string}
+ */
+CommandResult.prototype.toString = function() {
+  return JSON.stringify(this.toJSON());
+};
+
+module.exports = CommandResult;

node_modules/mongodb/lib/core/connection/commands.js

@@ -0,0 +1,507 @@
+'use strict';
+
+var retrieveBSON = require('./utils').retrieveBSON;
+var BSON = retrieveBSON();
+var Long = BSON.Long;
+const Buffer = require('safe-buffer').Buffer;
+
+// Incrementing request id
+var _requestId = 0;
+
+// Wire command operation ids
+var opcodes = require('../wireprotocol/shared').opcodes;
+
+// Query flags
+var OPTS_TAILABLE_CURSOR = 2;
+var OPTS_SLAVE = 4;
+var OPTS_OPLOG_REPLAY = 8;
+var OPTS_NO_CURSOR_TIMEOUT = 16;
+var OPTS_AWAIT_DATA = 32;
+var OPTS_EXHAUST = 64;
+var OPTS_PARTIAL = 128;
+
+// Response flags
+var CURSOR_NOT_FOUND = 1;
+var QUERY_FAILURE = 2;
+var SHARD_CONFIG_STALE = 4;
+var AWAIT_CAPABLE = 8;
+
+/**************************************************************
+ * QUERY
+ **************************************************************/
+var Query = function(bson, ns, query, options) {
+  var self = this;
+  // Basic options needed to be passed in
+  if (ns == null) throw new Error('ns must be specified for query');
+  if (query == null) throw new Error('query must be specified for query');
+
+  // Validate that we are not passing 0x00 in the collection name
+  if (ns.indexOf('\x00') !== -1) {
+    throw new Error('namespace cannot contain a null character');
+  }
+
+  // Basic options
+  this.bson = bson;
+  this.ns = ns;
+  this.query = query;
+
+  // Additional options
+  this.numberToSkip = options.numberToSkip || 0;
+  this.numberToReturn = options.numberToReturn || 0;
+  this.returnFieldSelector = options.returnFieldSelector || null;
+  this.requestId = Query.getRequestId();
+
+  // special case for pre-3.2 find commands, delete ASAP
+  this.pre32Limit = options.pre32Limit;
+
+  // Serialization option
+  this.serializeFunctions =
+    typeof options.serializeFunctions === 'boolean' ? options.serializeFunctions : false;
+  this.ignoreUndefined =
+    typeof options.ignoreUndefined === 'boolean' ? options.ignoreUndefined : false;
+  this.maxBsonSize = options.maxBsonSize || 1024 * 1024 * 16;
+  this.checkKeys = typeof options.checkKeys === 'boolean' ? options.checkKeys : true;
+  this.batchSize = self.numberToReturn;
+
+  // Flags
+  this.tailable = false;
+  this.slaveOk = typeof options.slaveOk === 'boolean' ? options.slaveOk : false;
+  this.oplogReplay = false;
+  this.noCursorTimeout = false;
+  this.awaitData = false;
+  this.exhaust = false;
+  this.partial = false;
+};
+
+//
+// Assign a new request Id
+Query.prototype.incRequestId = function() {
+  this.requestId = _requestId++;
+};
+
+//
+// Assign a new request Id
+Query.nextRequestId = function() {
+  return _requestId + 1;
+};
+
+//
+// Uses a single allocated buffer for the process, avoiding multiple memory allocations
+Query.prototype.toBin = function() {
+  var self = this;
+  var buffers = [];
+  var projection = null;
+
+  // Set up the flags
+  var flags = 0;
+  if (this.tailable) {
+    flags |= OPTS_TAILABLE_CURSOR;
+  }
+
+  if (this.slaveOk) {
+    flags |= OPTS_SLAVE;
+  }
+
+  if (this.oplogReplay) {
+    flags |= OPTS_OPLOG_REPLAY;
+  }
+
+  if (this.noCursorTimeout) {
+    flags |= OPTS_NO_CURSOR_TIMEOUT;
+  }
+
+  if (this.awaitData) {
+    flags |= OPTS_AWAIT_DATA;
+  }
+
+  if (this.exhaust) {
+    flags |= OPTS_EXHAUST;
+  }
+
+  if (this.partial) {
+    flags |= OPTS_PARTIAL;
+  }
+
+  // If batchSize is different to self.numberToReturn
+  if (self.batchSize !== self.numberToReturn) self.numberToReturn = self.batchSize;
+
+  // Allocate write protocol header buffer
+  var header = Buffer.alloc(
+    4 * 4 + // Header
+    4 + // Flags
+    Buffer.byteLength(self.ns) +
+    1 + // namespace
+    4 + // numberToSkip
+      4 // numberToReturn
+  );
+
+  // Add header to buffers
+  buffers.push(header);
+
+  // Serialize the query
+  var query = self.bson.serialize(this.query, {
+    checkKeys: this.checkKeys,
+    serializeFunctions: this.serializeFunctions,
+    ignoreUndefined: this.ignoreUndefined
+  });
+
+  // Add query document
+  buffers.push(query);
+
+  if (self.returnFieldSelector && Object.keys(self.returnFieldSelector).length > 0) {
+    // Serialize the projection document
+    projection = self.bson.serialize(this.returnFieldSelector, {
+      checkKeys: this.checkKeys,
+      serializeFunctions: this.serializeFunctions,
+      ignoreUndefined: this.ignoreUndefined
+    });
+    // Add projection document
+    buffers.push(projection);
+  }
+
+  // Total message size
+  var totalLength = header.length + query.length + (projection ? projection.length : 0);
+
+  // Set up the index
+  var index = 4;
+
+  // Write total document length
+  header[3] = (totalLength >> 24) & 0xff;
+  header[2] = (totalLength >> 16) & 0xff;
+  header[1] = (totalLength >> 8) & 0xff;
+  header[0] = totalLength & 0xff;
+
+  // Write header information requestId
+  header[index + 3] = (this.requestId >> 24) & 0xff;
+  header[index + 2] = (this.requestId >> 16) & 0xff;
+  header[index + 1] = (this.requestId >> 8) & 0xff;
+  header[index] = this.requestId & 0xff;
+  index = index + 4;
+
+  // Write header information responseTo
+  header[index + 3] = (0 >> 24) & 0xff;
+  header[index + 2] = (0 >> 16) & 0xff;
+  header[index + 1] = (0 >> 8) & 0xff;
+  header[index] = 0 & 0xff;
+  index = index + 4;
+
+  // Write header information OP_QUERY
+  header[index + 3] = (opcodes.OP_QUERY >> 24) & 0xff;
+  header[index + 2] = (opcodes.OP_QUERY >> 16) & 0xff;
+  header[index + 1] = (opcodes.OP_QUERY >> 8) & 0xff;
+  header[index] = opcodes.OP_QUERY & 0xff;
+  index = index + 4;
+
+  // Write header information flags
+  header[index + 3] = (flags >> 24) & 0xff;
+  header[index + 2] = (flags >> 16) & 0xff;
+  header[index + 1] = (flags >> 8) & 0xff;
+  header[index] = flags & 0xff;
+  index = index + 4;
+
+  // Write collection name
+  index = index + header.write(this.ns, index, 'utf8') + 1;
+  header[index - 1] = 0;
+
+  // Write header information flags numberToSkip
+  header[index + 3] = (this.numberToSkip >> 24) & 0xff;
+  header[index + 2] = (this.numberToSkip >> 16) & 0xff;
+  header[index + 1] = (this.numberToSkip >> 8) & 0xff;
+  header[index] = this.numberToSkip & 0xff;
+  index = index + 4;
+
+  // Write header information flags numberToReturn
+  header[index + 3] = (this.numberToReturn >> 24) & 0xff;
+  header[index + 2] = (this.numberToReturn >> 16) & 0xff;
+  header[index + 1] = (this.numberToReturn >> 8) & 0xff;
+  header[index] = this.numberToReturn & 0xff;
+  index = index + 4;
+
+  // Return the buffers
+  return buffers;
+};
+
+Query.getRequestId = function() {
+  return ++_requestId;
+};
+
+/**************************************************************
+ * GETMORE
+ **************************************************************/
+var GetMore = function(bson, ns, cursorId, opts) {
+  opts = opts || {};
+  this.numberToReturn = opts.numberToReturn || 0;
+  this.requestId = _requestId++;
+  this.bson = bson;
+  this.ns = ns;
+  this.cursorId = cursorId;
+};
+
+//
+// Uses a single allocated buffer for the process, avoiding multiple memory allocations
+GetMore.prototype.toBin = function() {
+  var length = 4 + Buffer.byteLength(this.ns) + 1 + 4 + 8 + 4 * 4;
+  // Create command buffer
+  var index = 0;
+  // Allocate buffer
+  var _buffer = Buffer.alloc(length);
+
+  // Write header information
+  // index = write32bit(index, _buffer, length);
+  _buffer[index + 3] = (length >> 24) & 0xff;
+  _buffer[index + 2] = (length >> 16) & 0xff;
+  _buffer[index + 1] = (length >> 8) & 0xff;
+  _buffer[index] = length & 0xff;
+  index = index + 4;
+
+  // index = write32bit(index, _buffer, requestId);
+  _buffer[index + 3] = (this.requestId >> 24) & 0xff;
+  _buffer[index + 2] = (this.requestId >> 16) & 0xff;
+  _buffer[index + 1] = (this.requestId >> 8) & 0xff;
+  _buffer[index] = this.requestId & 0xff;
+  index = index + 4;
+
+  // index = write32bit(index, _buffer, 0);
+  _buffer[index + 3] = (0 >> 24) & 0xff;
+  _buffer[index + 2] = (0 >> 16) & 0xff;
+  _buffer[index + 1] = (0 >> 8) & 0xff;
+  _buffer[index] = 0 & 0xff;
+  index = index + 4;
+
+  // index = write32bit(index, _buffer, OP_GETMORE);
+  _buffer[index + 3] = (opcodes.OP_GETMORE >> 24) & 0xff;
+  _buffer[index + 2] = (opcodes.OP_GETMORE >> 16) & 0xff;
+  _buffer[index + 1] = (opcodes.OP_GETMORE >> 8) & 0xff;
+  _buffer[index] = opcodes.OP_GETMORE & 0xff;
+  index = index + 4;
+
+  // index = write32bit(index, _buffer, 0);
+  _buffer[index + 3] = (0 >> 24) & 0xff;
+  _buffer[index + 2] = (0 >> 16) & 0xff;
+  _buffer[index + 1] = (0 >> 8) & 0xff;
+  _buffer[index] = 0 & 0xff;
+  index = index + 4;
+
+  // Write collection name
+  index = index + _buffer.write(this.ns, index, 'utf8') + 1;
+  _buffer[index - 1] = 0;
+
+  // Write batch size
+  // index = write32bit(index, _buffer, numberToReturn);
+  _buffer[index + 3] = (this.numberToReturn >> 24) & 0xff;
+  _buffer[index + 2] = (this.numberToReturn >> 16) & 0xff;
+  _buffer[index + 1] = (this.numberToReturn >> 8) & 0xff;
+  _buffer[index] = this.numberToReturn & 0xff;
+  index = index + 4;
+
+  // Write cursor id
+  // index = write32bit(index, _buffer, cursorId.getLowBits());
+  _buffer[index + 3] = (this.cursorId.getLowBits() >> 24) & 0xff;
+  _buffer[index + 2] = (this.cursorId.getLowBits() >> 16) & 0xff;
+  _buffer[index + 1] = (this.cursorId.getLowBits() >> 8) & 0xff;
+  _buffer[index] = this.cursorId.getLowBits() & 0xff;
+  index = index + 4;
+
+  // index = write32bit(index, _buffer, cursorId.getHighBits());
+  _buffer[index + 3] = (this.cursorId.getHighBits() >> 24) & 0xff;
+  _buffer[index + 2] = (this.cursorId.getHighBits() >> 16) & 0xff;
+  _buffer[index + 1] = (this.cursorId.getHighBits() >> 8) & 0xff;
+  _buffer[index] = this.cursorId.getHighBits() & 0xff;
+  index = index + 4;
+
+  // Return buffer
+  return _buffer;
+};
+
+/**************************************************************
+ * KILLCURSOR
+ **************************************************************/
+var KillCursor = function(bson, ns, cursorIds) {
+  this.ns = ns;
+  this.requestId = _requestId++;
+  this.cursorIds = cursorIds;
+};
+
+//
+// Uses a single allocated buffer for the process, avoiding multiple memory allocations
+KillCursor.prototype.toBin = function() {
+  var length = 4 + 4 + 4 * 4 + this.cursorIds.length * 8;
+
+  // Create command buffer
+  var index = 0;
+  var _buffer = Buffer.alloc(length);
+
+  // Write header information
+  // index = write32bit(index, _buffer, length);
+  _buffer[index + 3] = (length >> 24) & 0xff;
+  _buffer[index + 2] = (length >> 16) & 0xff;
+  _buffer[index + 1] = (length >> 8) & 0xff;
+  _buffer[index] = length & 0xff;
+  index = index + 4;
+
+  // index = write32bit(index, _buffer, requestId);
+  _buffer[index + 3] = (this.requestId >> 24) & 0xff;
+  _buffer[index + 2] = (this.requestId >> 16) & 0xff;
+  _buffer[index + 1] = (this.requestId >> 8) & 0xff;
+  _buffer[index] = this.requestId & 0xff;
+  index = index + 4;
+
+  // index = write32bit(index, _buffer, 0);
+  _buffer[index + 3] = (0 >> 24) & 0xff;
+  _buffer[index + 2] = (0 >> 16) & 0xff;
+  _buffer[index + 1] = (0 >> 8) & 0xff;
+  _buffer[index] = 0 & 0xff;
+  index = index + 4;
+
+  // index = write32bit(index, _buffer, OP_KILL_CURSORS);
+  _buffer[index + 3] = (opcodes.OP_KILL_CURSORS >> 24) & 0xff;
+  _buffer[index + 2] = (opcodes.OP_KILL_CURSORS >> 16) & 0xff;
+  _buffer[index + 1] = (opcodes.OP_KILL_CURSORS >> 8) & 0xff;
+  _buffer[index] = opcodes.OP_KILL_CURSORS & 0xff;
+  index = index + 4;
+
+  // index = write32bit(index, _buffer, 0);
+  _buffer[index + 3] = (0 >> 24) & 0xff;
+  _buffer[index + 2] = (0 >> 16) & 0xff;
+  _buffer[index + 1] = (0 >> 8) & 0xff;
+  _buffer[index] = 0 & 0xff;
+  index = index + 4;
+
+  // Write batch size
+  // index = write32bit(index, _buffer, this.cursorIds.length);
+  _buffer[index + 3] = (this.cursorIds.length >> 24) & 0xff;
+  _buffer[index + 2] = (this.cursorIds.length >> 16) & 0xff;
+  _buffer[index + 1] = (this.cursorIds.length >> 8) & 0xff;
+  _buffer[index] = this.cursorIds.length & 0xff;
+  index = index + 4;
+
+  // Write all the cursor ids into the array
+  for (var i = 0; i < this.cursorIds.length; i++) {
+    // Write cursor id
+    // index = write32bit(index, _buffer, cursorIds[i].getLowBits());
+    _buffer[index + 3] = (this.cursorIds[i].getLowBits() >> 24) & 0xff;
+    _buffer[index + 2] = (this.cursorIds[i].getLowBits() >> 16) & 0xff;
+    _buffer[index + 1] = (this.cursorIds[i].getLowBits() >> 8) & 0xff;
+    _buffer[index] = this.cursorIds[i].getLowBits() & 0xff;
+    index = index + 4;
+
+    // index = write32bit(index, _buffer, cursorIds[i].getHighBits());
+    _buffer[index + 3] = (this.cursorIds[i].getHighBits() >> 24) & 0xff;
+    _buffer[index + 2] = (this.cursorIds[i].getHighBits() >> 16) & 0xff;
+    _buffer[index + 1] = (this.cursorIds[i].getHighBits() >> 8) & 0xff;
+    _buffer[index] = this.cursorIds[i].getHighBits() & 0xff;
+    index = index + 4;
+  }
+
+  // Return buffer
+  return _buffer;
+};
+
+var Response = function(bson, message, msgHeader, msgBody, opts) {
+  opts = opts || { promoteLongs: true, promoteValues: true, promoteBuffers: false };
+  this.parsed = false;
+  this.raw = message;
+  this.data = msgBody;
+  this.bson = bson;
+  this.opts = opts;
+
+  // Read the message header
+  this.length = msgHeader.length;
+  this.requestId = msgHeader.requestId;
+  this.responseTo = msgHeader.responseTo;
+  this.opCode = msgHeader.opCode;
+  this.fromCompressed = msgHeader.fromCompressed;
+
+  // Read the message body
+  this.responseFlags = msgBody.readInt32LE(0);
+  this.cursorId = new Long(msgBody.readInt32LE(4), msgBody.readInt32LE(8));
+  this.startingFrom = msgBody.readInt32LE(12);
+  this.numberReturned = msgBody.readInt32LE(16);
+
+  // Preallocate document array
+  this.documents = new Array(this.numberReturned);
+
+  // Flag values
+  this.cursorNotFound = (this.responseFlags & CURSOR_NOT_FOUND) !== 0;
+  this.queryFailure = (this.responseFlags & QUERY_FAILURE) !== 0;
+  this.shardConfigStale = (this.responseFlags & SHARD_CONFIG_STALE) !== 0;
+  this.awaitCapable = (this.responseFlags & AWAIT_CAPABLE) !== 0;
+  this.promoteLongs = typeof opts.promoteLongs === 'boolean' ? opts.promoteLongs : true;
+  this.promoteValues = typeof opts.promoteValues === 'boolean' ? opts.promoteValues : true;
+  this.promoteBuffers = typeof opts.promoteBuffers === 'boolean' ? opts.promoteBuffers : false;
+};
+
+Response.prototype.isParsed = function() {
+  return this.parsed;
+};
+
+Response.prototype.parse = function(options) {
+  // Don't parse again if not needed
+  if (this.parsed) return;
+  options = options || {};
+
+  // Allow the return of raw documents instead of parsing
+  var raw = options.raw || false;
+  var documentsReturnedIn = options.documentsReturnedIn || null;
+  var promoteLongs =
+    typeof options.promoteLongs === 'boolean' ? options.promoteLongs : this.opts.promoteLongs;
+  var promoteValues =
+    typeof options.promoteValues === 'boolean' ? options.promoteValues : this.opts.promoteValues;
+  var promoteBuffers =
+    typeof options.promoteBuffers === 'boolean' ? options.promoteBuffers : this.opts.promoteBuffers;
+  var bsonSize, _options;
+
+  // Set up the options
+  _options = {
+    promoteLongs: promoteLongs,
+    promoteValues: promoteValues,
+    promoteBuffers: promoteBuffers
+  };
+
+  // Position within OP_REPLY at which documents start
+  // (See https://docs.mongodb.com/manual/reference/mongodb-wire-protocol/#wire-op-reply)
+  this.index = 20;
+
+  //
+  // Parse Body
+  //
+  for (var i = 0; i < this.numberReturned; i++) {
+    bsonSize =
+      this.data[this.index] |
+      (this.data[this.index + 1] << 8) |
+      (this.data[this.index + 2] << 16) |
+      (this.data[this.index + 3] << 24);
+
+    // If we have raw results specified slice the return document
+    if (raw) {
+      this.documents[i] = this.data.slice(this.index, this.index + bsonSize);
+    } else {
+      this.documents[i] = this.bson.deserialize(
+        this.data.slice(this.index, this.index + bsonSize),
+        _options
+      );
+    }
+
+    // Adjust the index
+    this.index = this.index + bsonSize;
+  }
+
+  if (this.documents.length === 1 && documentsReturnedIn != null && raw) {
+    const fieldsAsRaw = {};
+    fieldsAsRaw[documentsReturnedIn] = true;
+    _options.fieldsAsRaw = fieldsAsRaw;
+
+    const doc = this.bson.deserialize(this.documents[0], _options);
+    this.documents = [doc];
+  }
+
+  // Set parsed
+  this.parsed = true;
+};
+
+module.exports = {
+  Query: Query,
+  GetMore: GetMore,
+  Response: Response,
+  KillCursor: KillCursor
+};

node_modules/mongodb/lib/core/connection/connect.js

@@ -0,0 +1,352 @@
+'use strict';
+const net = require('net');
+const tls = require('tls');
+const Connection = require('./connection');
+const MongoError = require('../error').MongoError;
+const MongoNetworkError = require('../error').MongoNetworkError;
+const MongoNetworkTimeoutError = require('../error').MongoNetworkTimeoutError;
+const defaultAuthProviders = require('../auth/defaultAuthProviders').defaultAuthProviders;
+const AuthContext = require('../auth/auth_provider').AuthContext;
+const WIRE_CONSTANTS = require('../wireprotocol/constants');
+const makeClientMetadata = require('../utils').makeClientMetadata;
+const MAX_SUPPORTED_WIRE_VERSION = WIRE_CONSTANTS.MAX_SUPPORTED_WIRE_VERSION;
+const MAX_SUPPORTED_SERVER_VERSION = WIRE_CONSTANTS.MAX_SUPPORTED_SERVER_VERSION;
+const MIN_SUPPORTED_WIRE_VERSION = WIRE_CONSTANTS.MIN_SUPPORTED_WIRE_VERSION;
+const MIN_SUPPORTED_SERVER_VERSION = WIRE_CONSTANTS.MIN_SUPPORTED_SERVER_VERSION;
+let AUTH_PROVIDERS;
+
+function connect(options, cancellationToken, callback) {
+  if (typeof cancellationToken === 'function') {
+    callback = cancellationToken;
+    cancellationToken = undefined;
+  }
+
+  const ConnectionType = options && options.connectionType ? options.connectionType : Connection;
+  if (AUTH_PROVIDERS == null) {
+    AUTH_PROVIDERS = defaultAuthProviders(options.bson);
+  }
+
+  const family = options.family !== void 0 ? options.family : 0;
+  makeConnection(family, options, cancellationToken, (err, socket) => {
+    if (err) {
+      callback(err, socket); // in the error case, `socket` is the originating error event name
+      return;
+    }
+
+    performInitialHandshake(new ConnectionType(socket, options), options, callback);
+  });
+}
+
+function isModernConnectionType(conn) {
+  return !(conn instanceof Connection);
+}
+
+function checkSupportedServer(ismaster, options) {
+  const serverVersionHighEnough =
+    ismaster &&
+    typeof ismaster.maxWireVersion === 'number' &&
+    ismaster.maxWireVersion >= MIN_SUPPORTED_WIRE_VERSION;
+  const serverVersionLowEnough =
+    ismaster &&
+    typeof ismaster.minWireVersion === 'number' &&
+    ismaster.minWireVersion <= MAX_SUPPORTED_WIRE_VERSION;
+
+  if (serverVersionHighEnough) {
+    if (serverVersionLowEnough) {
+      return null;
+    }
+
+    const message = `Server at ${options.host}:${options.port} reports minimum wire version ${ismaster.minWireVersion}, but this version of the Node.js Driver requires at most ${MAX_SUPPORTED_WIRE_VERSION} (MongoDB ${MAX_SUPPORTED_SERVER_VERSION})`;
+    return new MongoError(message);
+  }
+
+  const message = `Server at ${options.host}:${
+    options.port
+  } reports maximum wire version ${ismaster.maxWireVersion ||
+    0}, but this version of the Node.js Driver requires at least ${MIN_SUPPORTED_WIRE_VERSION} (MongoDB ${MIN_SUPPORTED_SERVER_VERSION})`;
+  return new MongoError(message);
+}
+
+function performInitialHandshake(conn, options, _callback) {
+  const callback = function(err, ret) {
+    if (err && conn) {
+      conn.destroy();
+    }
+    _callback(err, ret);
+  };
+
+  const credentials = options.credentials;
+  if (credentials) {
+    if (!credentials.mechanism.match(/DEFAULT/i) && !AUTH_PROVIDERS[credentials.mechanism]) {
+      callback(new MongoError(`authMechanism '${credentials.mechanism}' not supported`));
+      return;
+    }
+  }
+
+  const authContext = new AuthContext(conn, credentials, options);
+  prepareHandshakeDocument(authContext, (err, handshakeDoc) => {
+    if (err) {
+      return callback(err);
+    }
+
+    const handshakeOptions = Object.assign({}, options);
+    if (options.connectTimeoutMS || options.connectionTimeout) {
+      // The handshake technically is a monitoring check, so its socket timeout should be connectTimeoutMS
+      handshakeOptions.socketTimeout = options.connectTimeoutMS || options.connectionTimeout;
+    }
+
+    const start = new Date().getTime();
+    conn.command('admin.$cmd', handshakeDoc, handshakeOptions, (err, result) => {
+      if (err) {
+        callback(err);
+        return;
+      }
+
+      const response = result.result;
+      if (response.ok === 0) {
+        callback(new MongoError(response));
+        return;
+      }
+
+      const supportedServerErr = checkSupportedServer(response, options);
+      if (supportedServerErr) {
+        callback(supportedServerErr);
+        return;
+      }
+
+      if (!isModernConnectionType(conn)) {
+        // resolve compression
+        if (response.compression) {
+          const agreedCompressors = handshakeDoc.compression.filter(
+            compressor => response.compression.indexOf(compressor) !== -1
+          );
+
+          if (agreedCompressors.length) {
+            conn.agreedCompressor = agreedCompressors[0];
+          }
+
+          if (options.compression && options.compression.zlibCompressionLevel) {
+            conn.zlibCompressionLevel = options.compression.zlibCompressionLevel;
+          }
+        }
+      }
+
+      // NOTE: This is metadata attached to the connection while porting away from
+      //       handshake being done in the `Server` class. Likely, it should be
+      //       relocated, or at very least restructured.
+      conn.ismaster = response;
+      conn.lastIsMasterMS = new Date().getTime() - start;
+
+      if (!response.arbiterOnly && credentials) {
+        // store the response on auth context
+        Object.assign(authContext, { response });
+
+        const resolvedCredentials = credentials.resolveAuthMechanism(response);
+        const authProvider = AUTH_PROVIDERS[resolvedCredentials.mechanism];
+        authProvider.auth(authContext, err => {
+          if (err) return callback(err);
+          callback(undefined, conn);
+        });
+
+        return;
+      }
+
+      callback(undefined, conn);
+    });
+  });
+}
+
+function prepareHandshakeDocument(authContext, callback) {
+  const options = authContext.options;
+  const compressors =
+    options.compression && options.compression.compressors ? options.compression.compressors : [];
+
+  const handshakeDoc = {
+    ismaster: true,
+    client: options.metadata || makeClientMetadata(options),
+    compression: compressors
+  };
+
+  const credentials = authContext.credentials;
+  if (credentials) {
+    if (credentials.mechanism.match(/DEFAULT/i) && credentials.username) {
+      Object.assign(handshakeDoc, {
+        saslSupportedMechs: `${credentials.source}.${credentials.username}`
+      });
+
+      AUTH_PROVIDERS['scram-sha-256'].prepare(handshakeDoc, authContext, callback);
+      return;
+    }
+
+    const authProvider = AUTH_PROVIDERS[credentials.mechanism];
+    authProvider.prepare(handshakeDoc, authContext, callback);
+    return;
+  }
+
+  callback(undefined, handshakeDoc);
+}
+
+const LEGAL_SSL_SOCKET_OPTIONS = [
+  'pfx',
+  'key',
+  'passphrase',
+  'cert',
+  'ca',
+  'ciphers',
+  'NPNProtocols',
+  'ALPNProtocols',
+  'servername',
+  'ecdhCurve',
+  'secureProtocol',
+  'secureContext',
+  'session',
+  'minDHSize',
+  'crl',
+  'rejectUnauthorized'
+];
+
+function parseConnectOptions(family, options) {
+  const host = typeof options.host === 'string' ? options.host : 'localhost';
+  if (host.indexOf('/') !== -1) {
+    return { path: host };
+  }
+
+  const result = {
+    family,
+    host,
+    port: typeof options.port === 'number' ? options.port : 27017,
+    rejectUnauthorized: false
+  };
+
+  return result;
+}
+
+function parseSslOptions(family, options) {
+  const result = parseConnectOptions(family, options);
+
+  // Merge in valid SSL options
+  for (const name in options) {
+    if (options[name] != null && LEGAL_SSL_SOCKET_OPTIONS.indexOf(name) !== -1) {
+      result[name] = options[name];
+    }
+  }
+
+  // Override checkServerIdentity behavior
+  if (options.checkServerIdentity === false) {
+    // Skip the identiy check by retuning undefined as per node documents
+    // https://nodejs.org/api/tls.html#tls_tls_connect_options_callback
+    result.checkServerIdentity = function() {
+      return undefined;
+    };
+  } else if (typeof options.checkServerIdentity === 'function') {
+    result.checkServerIdentity = options.checkServerIdentity;
+  }
+
+  // Set default sni servername to be the same as host
+  if (result.servername == null) {
+    result.servername = result.host;
+  }
+
+  return result;
+}
+
+const SOCKET_ERROR_EVENTS = new Set(['error', 'close', 'timeout', 'parseError']);
+function makeConnection(family, options, cancellationToken, _callback) {
+  const useSsl = typeof options.ssl === 'boolean' ? options.ssl : false;
+  const keepAlive = typeof options.keepAlive === 'boolean' ? options.keepAlive : true;
+  let keepAliveInitialDelay =
+    typeof options.keepAliveInitialDelay === 'number' ? options.keepAliveInitialDelay : 120000;
+  const noDelay = typeof options.noDelay === 'boolean' ? options.noDelay : true;
+  const connectionTimeout =
+    typeof options.connectionTimeout === 'number'
+      ? options.connectionTimeout
+      : typeof options.connectTimeoutMS === 'number'
+      ? options.connectTimeoutMS
+      : 30000;
+  const socketTimeout = typeof options.socketTimeout === 'number' ? options.socketTimeout : 360000;
+  const rejectUnauthorized =
+    typeof options.rejectUnauthorized === 'boolean' ? options.rejectUnauthorized : true;
+
+  if (keepAliveInitialDelay > socketTimeout) {
+    keepAliveInitialDelay = Math.round(socketTimeout / 2);
+  }
+
+  let socket;
+  const callback = function(err, ret) {
+    if (err && socket) {
+      socket.destroy();
+    }
+
+    _callback(err, ret);
+  };
+
+  try {
+    if (useSsl) {
+      socket = tls.connect(parseSslOptions(family, options));
+      if (typeof socket.disableRenegotiation === 'function') {
+        socket.disableRenegotiation();
+      }
+    } else {
+      socket = net.createConnection(parseConnectOptions(family, options));
+    }
+  } catch (err) {
+    return callback(err);
+  }
+
+  socket.setKeepAlive(keepAlive, keepAliveInitialDelay);
+  socket.setTimeout(connectionTimeout);
+  socket.setNoDelay(noDelay);
+
+  const connectEvent = useSsl ? 'secureConnect' : 'connect';
+  let cancellationHandler;
+  function errorHandler(eventName) {
+    return err => {
+      SOCKET_ERROR_EVENTS.forEach(event => socket.removeAllListeners(event));
+      if (cancellationHandler) {
+        cancellationToken.removeListener('cancel', cancellationHandler);
+      }
+
+      socket.removeListener(connectEvent, connectHandler);
+      callback(connectionFailureError(eventName, err));
+    };
+  }
+
+  function connectHandler() {
+    SOCKET_ERROR_EVENTS.forEach(event => socket.removeAllListeners(event));
+    if (cancellationHandler) {
+      cancellationToken.removeListener('cancel', cancellationHandler);
+    }
+
+    if (socket.authorizationError && rejectUnauthorized) {
+      return callback(socket.authorizationError);
+    }
+
+    socket.setTimeout(socketTimeout);
+    callback(null, socket);
+  }
+
+  SOCKET_ERROR_EVENTS.forEach(event => socket.once(event, errorHandler(event)));
+  if (cancellationToken) {
+    cancellationHandler = errorHandler('cancel');
+    cancellationToken.once('cancel', cancellationHandler);
+  }
+
+  socket.once(connectEvent, connectHandler);
+}
+
+function connectionFailureError(type, err) {
+  switch (type) {
+    case 'error':
+      return new MongoNetworkError(err);
+    case 'timeout':
+      return new MongoNetworkTimeoutError(`connection timed out`);
+    case 'close':
+      return new MongoNetworkError(`connection closed`);
+    case 'cancel':
+      return new MongoNetworkError(`connection establishment was cancelled`);
+    default:
+      return new MongoNetworkError(`unknown network error`);
+  }
+}
+
+module.exports = connect;

node_modules/mongodb/lib/core/connection/connection.js

@@ -0,0 +1,712 @@
+'use strict';
+
+const EventEmitter = require('events').EventEmitter;
+const crypto = require('crypto');
+const debugOptions = require('./utils').debugOptions;
+const parseHeader = require('../wireprotocol/shared').parseHeader;
+const decompress = require('../wireprotocol/compression').decompress;
+const Response = require('./commands').Response;
+const BinMsg = require('./msg').BinMsg;
+const MongoNetworkError = require('../error').MongoNetworkError;
+const MongoNetworkTimeoutError = require('../error').MongoNetworkTimeoutError;
+const MongoError = require('../error').MongoError;
+const Logger = require('./logger');
+const OP_COMPRESSED = require('../wireprotocol/shared').opcodes.OP_COMPRESSED;
+const OP_MSG = require('../wireprotocol/shared').opcodes.OP_MSG;
+const MESSAGE_HEADER_SIZE = require('../wireprotocol/shared').MESSAGE_HEADER_SIZE;
+const Buffer = require('safe-buffer').Buffer;
+const Query = require('./commands').Query;
+const CommandResult = require('./command_result');
+
+let _id = 0;
+
+const DEFAULT_MAX_BSON_MESSAGE_SIZE = 1024 * 1024 * 16 * 4;
+const DEBUG_FIELDS = [
+  'host',
+  'port',
+  'size',
+  'keepAlive',
+  'keepAliveInitialDelay',
+  'noDelay',
+  'connectionTimeout',
+  'socketTimeout',
+  'ssl',
+  'ca',
+  'crl',
+  'cert',
+  'rejectUnauthorized',
+  'promoteLongs',
+  'promoteValues',
+  'promoteBuffers',
+  'checkServerIdentity'
+];
+
+let connectionAccountingSpy = undefined;
+let connectionAccounting = false;
+let connections = {};
+
+/**
+ * A class representing a single connection to a MongoDB server
+ *
+ * @fires Connection#connect
+ * @fires Connection#close
+ * @fires Connection#error
+ * @fires Connection#timeout
+ * @fires Connection#parseError
+ * @fires Connection#message
+ */
+class Connection extends EventEmitter {
+  /**
+   * Creates a new Connection instance
+   *
+   * **NOTE**: Internal class, do not instantiate directly
+   *
+   * @param {Socket} socket The socket this connection wraps
+   * @param {Object} options Various settings
+   * @param {object} options.bson An implementation of bson serialize and deserialize
+   * @param {string} [options.host='localhost'] The host the socket is connected to
+   * @param {number} [options.port=27017] The port used for the socket connection
+   * @param {boolean} [options.keepAlive=true] TCP Connection keep alive enabled
+   * @param {number} [options.keepAliveInitialDelay=120000] Initial delay before TCP keep alive enabled
+   * @param {number} [options.connectionTimeout=30000] TCP Connection timeout setting
+   * @param {number} [options.socketTimeout=360000] TCP Socket timeout setting
+   * @param {boolean} [options.promoteLongs] Convert Long values from the db into Numbers if they fit into 53 bits
+   * @param {boolean} [options.promoteValues] Promotes BSON values to native types where possible, set to false to only receive wrapper types.
+   * @param {boolean} [options.promoteBuffers] Promotes Binary BSON values to native Node Buffers.
+   * @param {number} [options.maxBsonMessageSize=0x4000000] Largest possible size of a BSON message (for legacy purposes)
+   */
+  constructor(socket, options) {
+    super();
+
+    options = options || {};
+    if (!options.bson) {
+      throw new TypeError('must pass in valid bson parser');
+    }
+
+    this.id = _id++;
+    this.options = options;
+    this.logger = Logger('Connection', options);
+    this.bson = options.bson;
+    this.tag = options.tag;
+    this.maxBsonMessageSize = options.maxBsonMessageSize || DEFAULT_MAX_BSON_MESSAGE_SIZE;
+
+    this.port = options.port || 27017;
+    this.host = options.host || 'localhost';
+    this.socketTimeout = typeof options.socketTimeout === 'number' ? options.socketTimeout : 360000;
+
+    // These values are inspected directly in tests, but maybe not necessary to keep around
+    this.keepAlive = typeof options.keepAlive === 'boolean' ? options.keepAlive : true;
+    this.keepAliveInitialDelay =
+      typeof options.keepAliveInitialDelay === 'number' ? options.keepAliveInitialDelay : 120000;
+    this.connectionTimeout =
+      typeof options.connectionTimeout === 'number' ? options.connectionTimeout : 30000;
+    if (this.keepAliveInitialDelay > this.socketTimeout) {
+      this.keepAliveInitialDelay = Math.round(this.socketTimeout / 2);
+    }
+
+    // Debug information
+    if (this.logger.isDebug()) {
+      this.logger.debug(
+        `creating connection ${this.id} with options [${JSON.stringify(
+          debugOptions(DEBUG_FIELDS, options)
+        )}]`
+      );
+    }
+
+    // Response options
+    this.responseOptions = {
+      promoteLongs: typeof options.promoteLongs === 'boolean' ? options.promoteLongs : true,
+      promoteValues: typeof options.promoteValues === 'boolean' ? options.promoteValues : true,
+      promoteBuffers: typeof options.promoteBuffers === 'boolean' ? options.promoteBuffers : false
+    };
+
+    // Flushing
+    this.flushing = false;
+    this.queue = [];
+
+    // Internal state
+    this.writeStream = null;
+    this.destroyed = false;
+    this.timedOut = false;
+
+    // Create hash method
+    const hash = crypto.createHash('sha1');
+    hash.update(this.address);
+    this.hashedName = hash.digest('hex');
+
+    // All operations in flight on the connection
+    this.workItems = [];
+
+    // setup socket
+    this.socket = socket;
+    this.socket.once('error', errorHandler(this));
+    this.socket.once('timeout', timeoutHandler(this));
+    this.socket.once('close', closeHandler(this));
+    this.socket.on('data', dataHandler(this));
+
+    if (connectionAccounting) {
+      addConnection(this.id, this);
+    }
+  }
+
+  setSocketTimeout(value) {
+    if (this.socket) {
+      this.socket.setTimeout(value);
+    }
+  }
+
+  resetSocketTimeout() {
+    if (this.socket) {
+      this.socket.setTimeout(this.socketTimeout);
+    }
+  }
+
+  static enableConnectionAccounting(spy) {
+    if (spy) {
+      connectionAccountingSpy = spy;
+    }
+
+    connectionAccounting = true;
+    connections = {};
+  }
+
+  static disableConnectionAccounting() {
+    connectionAccounting = false;
+    connectionAccountingSpy = undefined;
+  }
+
+  static connections() {
+    return connections;
+  }
+
+  get address() {
+    return `${this.host}:${this.port}`;
+  }
+
+  /**
+   * Unref this connection
+   * @method
+   * @return {boolean}
+   */
+  unref() {
+    if (this.socket == null) {
+      this.once('connect', () => this.socket.unref());
+      return;
+    }
+
+    this.socket.unref();
+  }
+
+  /**
+   * Flush all work Items on this connection
+   *
+   * @param {*} err The error to propagate to the flushed work items
+   */
+  flush(err) {
+    while (this.workItems.length > 0) {
+      const workItem = this.workItems.shift();
+      if (workItem.cb) {
+        workItem.cb(err);
+      }
+    }
+  }
+
+  /**
+   * Destroy connection
+   * @method
+   */
+  destroy(options, callback) {
+    if (typeof options === 'function') {
+      callback = options;
+      options = {};
+    }
+
+    options = Object.assign({ force: false }, options);
+
+    if (connectionAccounting) {
+      deleteConnection(this.id);
+    }
+
+    if (this.socket == null) {
+      this.destroyed = true;
+      return;
+    }
+
+    if (options.force || this.timedOut) {
+      this.socket.destroy();
+      this.destroyed = true;
+      if (typeof callback === 'function') callback(null, null);
+      return;
+    }
+
+    this.socket.end(err => {
+      this.destroyed = true;
+      if (typeof callback === 'function') callback(err, null);
+    });
+  }
+
+  /**
+   * Write to connection
+   * @method
+   * @param {Command} command Command to write out need to implement toBin and toBinUnified
+   */
+  write(buffer) {
+    // Debug Log
+    if (this.logger.isDebug()) {
+      if (!Array.isArray(buffer)) {
+        this.logger.debug(`writing buffer [${buffer.toString('hex')}] to ${this.address}`);
+      } else {
+        for (let i = 0; i < buffer.length; i++)
+          this.logger.debug(`writing buffer [${buffer[i].toString('hex')}] to ${this.address}`);
+      }
+    }
+
+    // Double check that the connection is not destroyed
+    if (this.socket.destroyed === false) {
+      // Write out the command
+      if (!Array.isArray(buffer)) {
+        this.socket.write(buffer, 'binary');
+        return true;
+      }
+
+      // Iterate over all buffers and write them in order to the socket
+      for (let i = 0; i < buffer.length; i++) {
+        this.socket.write(buffer[i], 'binary');
+      }
+
+      return true;
+    }
+
+    // Connection is destroyed return write failed
+    return false;
+  }
+
+  /**
+   * Return id of connection as a string
+   * @method
+   * @return {string}
+   */
+  toString() {
+    return '' + this.id;
+  }
+
+  /**
+   * Return json object of connection
+   * @method
+   * @return {object}
+   */
+  toJSON() {
+    return { id: this.id, host: this.host, port: this.port };
+  }
+
+  /**
+   * Is the connection connected
+   * @method
+   * @return {boolean}
+   */
+  isConnected() {
+    if (this.destroyed) return false;
+    return !this.socket.destroyed && this.socket.writable;
+  }
+
+  /**
+   * @ignore
+   */
+  command(ns, command, options, callback) {
+    if (typeof options === 'function') (callback = options), (options = {});
+
+    const conn = this;
+    const socketTimeout =
+      typeof options.socketTimeout === 'number' ? options.socketTimeout : 360000;
+    const bson = conn.options.bson;
+    const query = new Query(bson, ns, command, {
+      numberToSkip: 0,
+      numberToReturn: 1
+    });
+
+    const noop = () => {};
+    function _callback(err, result) {
+      callback(err, result);
+      callback = noop;
+    }
+
+    function errorHandler(err) {
+      conn.resetSocketTimeout();
+      CONNECTION_ERROR_EVENTS.forEach(eventName => conn.removeListener(eventName, errorHandler));
+      conn.removeListener('message', messageHandler);
+
+      if (err == null) {
+        err = new MongoError(`runCommand failed for connection to '${conn.address}'`);
+      }
+
+      // ignore all future errors
+      conn.on('error', noop);
+      _callback(err);
+    }
+
+    function messageHandler(msg) {
+      if (msg.responseTo !== query.requestId) {
+        return;
+      }
+
+      conn.resetSocketTimeout();
+      CONNECTION_ERROR_EVENTS.forEach(eventName => conn.removeListener(eventName, errorHandler));
+      conn.removeListener('message', messageHandler);
+
+      msg.parse({ promoteValues: true });
+
+      const response = msg.documents[0];
+      if (response.ok === 0 || response.$err || response.errmsg || response.code) {
+        _callback(new MongoError(response));
+        return;
+      }
+
+      _callback(undefined, new CommandResult(response, this, msg));
+    }
+
+    conn.setSocketTimeout(socketTimeout);
+    CONNECTION_ERROR_EVENTS.forEach(eventName => conn.once(eventName, errorHandler));
+    conn.on('message', messageHandler);
+    conn.write(query.toBin());
+  }
+}
+
+const CONNECTION_ERROR_EVENTS = ['error', 'close', 'timeout', 'parseError'];
+
+function deleteConnection(id) {
+  // console.log("=== deleted connection " + id + " :: " + (connections[id] ? connections[id].port : ''))
+  delete connections[id];
+
+  if (connectionAccountingSpy) {
+    connectionAccountingSpy.deleteConnection(id);
+  }
+}
+
+function addConnection(id, connection) {
+  // console.log("=== added connection " + id + " :: " + connection.port)
+  connections[id] = connection;
+
+  if (connectionAccountingSpy) {
+    connectionAccountingSpy.addConnection(id, connection);
+  }
+}
+
+//
+// Connection handlers
+function errorHandler(conn) {
+  return function(err) {
+    if (connectionAccounting) deleteConnection(conn.id);
+    // Debug information
+    if (conn.logger.isDebug()) {
+      conn.logger.debug(
+        `connection ${conn.id} for [${conn.address}] errored out with [${JSON.stringify(err)}]`
+      );
+    }
+
+    conn.emit('error', new MongoNetworkError(err), conn);
+  };
+}
+
+function timeoutHandler(conn) {
+  return function() {
+    if (connectionAccounting) deleteConnection(conn.id);
+
+    if (conn.logger.isDebug()) {
+      conn.logger.debug(`connection ${conn.id} for [${conn.address}] timed out`);
+    }
+
+    conn.timedOut = true;
+    conn.emit(
+      'timeout',
+      new MongoNetworkTimeoutError(`connection ${conn.id} to ${conn.address} timed out`, {
+        beforeHandshake: conn.ismaster == null
+      }),
+      conn
+    );
+  };
+}
+
+function closeHandler(conn) {
+  return function(hadError) {
+    if (connectionAccounting) deleteConnection(conn.id);
+
+    if (conn.logger.isDebug()) {
+      conn.logger.debug(`connection ${conn.id} with for [${conn.address}] closed`);
+    }
+
+    if (!hadError) {
+      conn.emit(
+        'close',
+        new MongoNetworkError(`connection ${conn.id} to ${conn.address} closed`),
+        conn
+      );
+    }
+  };
+}
+
+// Handle a message once it is received
+function processMessage(conn, message) {
+  const msgHeader = parseHeader(message);
+  if (msgHeader.opCode !== OP_COMPRESSED) {
+    const ResponseConstructor = msgHeader.opCode === OP_MSG ? BinMsg : Response;
+    conn.emit(
+      'message',
+      new ResponseConstructor(
+        conn.bson,
+        message,
+        msgHeader,
+        message.slice(MESSAGE_HEADER_SIZE),
+        conn.responseOptions
+      ),
+      conn
+    );
+
+    return;
+  }
+
+  msgHeader.fromCompressed = true;
+  let index = MESSAGE_HEADER_SIZE;
+  msgHeader.opCode = message.readInt32LE(index);
+  index += 4;
+  msgHeader.length = message.readInt32LE(index);
+  index += 4;
+  const compressorID = message[index];
+  index++;
+
+  decompress(compressorID, message.slice(index), (err, decompressedMsgBody) => {
+    if (err) {
+      conn.emit('error', err);
+      return;
+    }
+
+    if (decompressedMsgBody.length !== msgHeader.length) {
+      conn.emit(
+        'error',
+        new MongoError(
+          'Decompressing a compressed message from the server failed. The message is corrupt.'
+        )
+      );
+
+      return;
+    }
+
+    const ResponseConstructor = msgHeader.opCode === OP_MSG ? BinMsg : Response;
+    conn.emit(
+      'message',
+      new ResponseConstructor(
+        conn.bson,
+        message,
+        msgHeader,
+        decompressedMsgBody,
+        conn.responseOptions
+      ),
+      conn
+    );
+  });
+}
+
+function dataHandler(conn) {
+  return function(data) {
+    // Parse until we are done with the data
+    while (data.length > 0) {
+      // If we still have bytes to read on the current message
+      if (conn.bytesRead > 0 && conn.sizeOfMessage > 0) {
+        // Calculate the amount of remaining bytes
+        const remainingBytesToRead = conn.sizeOfMessage - conn.bytesRead;
+        // Check if the current chunk contains the rest of the message
+        if (remainingBytesToRead > data.length) {
+          // Copy the new data into the exiting buffer (should have been allocated when we know the message size)
+          data.copy(conn.buffer, conn.bytesRead);
+          // Adjust the number of bytes read so it point to the correct index in the buffer
+          conn.bytesRead = conn.bytesRead + data.length;
+
+          // Reset state of buffer
+          data = Buffer.alloc(0);
+        } else {
+          // Copy the missing part of the data into our current buffer
+          data.copy(conn.buffer, conn.bytesRead, 0, remainingBytesToRead);
+          // Slice the overflow into a new buffer that we will then re-parse
+          data = data.slice(remainingBytesToRead);
+
+          // Emit current complete message
+          const emitBuffer = conn.buffer;
+          // Reset state of buffer
+          conn.buffer = null;
+          conn.sizeOfMessage = 0;
+          conn.bytesRead = 0;
+          conn.stubBuffer = null;
+
+          processMessage(conn, emitBuffer);
+        }
+      } else {
+        // Stub buffer is kept in case we don't get enough bytes to determine the
+        // size of the message (< 4 bytes)
+        if (conn.stubBuffer != null && conn.stubBuffer.length > 0) {
+          // If we have enough bytes to determine the message size let's do it
+          if (conn.stubBuffer.length + data.length > 4) {
+            // Prepad the data
+            const newData = Buffer.alloc(conn.stubBuffer.length + data.length);
+            conn.stubBuffer.copy(newData, 0);
+            data.copy(newData, conn.stubBuffer.length);
+            // Reassign for parsing
+            data = newData;
+
+            // Reset state of buffer
+            conn.buffer = null;
+            conn.sizeOfMessage = 0;
+            conn.bytesRead = 0;
+            conn.stubBuffer = null;
+          } else {
+            // Add the the bytes to the stub buffer
+            const newStubBuffer = Buffer.alloc(conn.stubBuffer.length + data.length);
+            // Copy existing stub buffer
+            conn.stubBuffer.copy(newStubBuffer, 0);
+            // Copy missing part of the data
+            data.copy(newStubBuffer, conn.stubBuffer.length);
+            // Exit parsing loop
+            data = Buffer.alloc(0);
+          }
+        } else {
+          if (data.length > 4) {
+            // Retrieve the message size
+            const sizeOfMessage = data[0] | (data[1] << 8) | (data[2] << 16) | (data[3] << 24);
+            // If we have a negative sizeOfMessage emit error and return
+            if (sizeOfMessage < 0 || sizeOfMessage > conn.maxBsonMessageSize) {
+              const errorObject = {
+                err: 'socketHandler',
+                trace: '',
+                bin: conn.buffer,
+                parseState: {
+                  sizeOfMessage: sizeOfMessage,
+                  bytesRead: conn.bytesRead,
+                  stubBuffer: conn.stubBuffer
+                }
+              };
+              // We got a parse Error fire it off then keep going
+              conn.emit('parseError', errorObject, conn);
+              return;
+            }
+
+            // Ensure that the size of message is larger than 0 and less than the max allowed
+            if (
+              sizeOfMessage > 4 &&
+              sizeOfMessage < conn.maxBsonMessageSize &&
+              sizeOfMessage > data.length
+            ) {
+              conn.buffer = Buffer.alloc(sizeOfMessage);
+              // Copy all the data into the buffer
+              data.copy(conn.buffer, 0);
+              // Update bytes read
+              conn.bytesRead = data.length;
+              // Update sizeOfMessage
+              conn.sizeOfMessage = sizeOfMessage;
+              // Ensure stub buffer is null
+              conn.stubBuffer = null;
+              // Exit parsing loop
+              data = Buffer.alloc(0);
+            } else if (
+              sizeOfMessage > 4 &&
+              sizeOfMessage < conn.maxBsonMessageSize &&
+              sizeOfMessage === data.length
+            ) {
+              const emitBuffer = data;
+              // Reset state of buffer
+              conn.buffer = null;
+              conn.sizeOfMessage = 0;
+              conn.bytesRead = 0;
+              conn.stubBuffer = null;
+              // Exit parsing loop
+              data = Buffer.alloc(0);
+              // Emit the message
+              processMessage(conn, emitBuffer);
+            } else if (sizeOfMessage <= 4 || sizeOfMessage > conn.maxBsonMessageSize) {
+              const errorObject = {
+                err: 'socketHandler',
+                trace: null,
+                bin: data,
+                parseState: {
+                  sizeOfMessage: sizeOfMessage,
+                  bytesRead: 0,
+                  buffer: null,
+                  stubBuffer: null
+                }
+              };
+              // We got a parse Error fire it off then keep going
+              conn.emit('parseError', errorObject, conn);
+
+              // Clear out the state of the parser
+              conn.buffer = null;
+              conn.sizeOfMessage = 0;
+              conn.bytesRead = 0;
+              conn.stubBuffer = null;
+              // Exit parsing loop
+              data = Buffer.alloc(0);
+            } else {
+              const emitBuffer = data.slice(0, sizeOfMessage);
+              // Reset state of buffer
+              conn.buffer = null;
+              conn.sizeOfMessage = 0;
+              conn.bytesRead = 0;
+              conn.stubBuffer = null;
+              // Copy rest of message
+              data = data.slice(sizeOfMessage);
+              // Emit the message
+              processMessage(conn, emitBuffer);
+            }
+          } else {
+            // Create a buffer that contains the space for the non-complete message
+            conn.stubBuffer = Buffer.alloc(data.length);
+            // Copy the data to the stub buffer
+            data.copy(conn.stubBuffer, 0);
+            // Exit parsing loop
+            data = Buffer.alloc(0);
+          }
+        }
+      }
+    }
+  };
+}
+
+/**
+ * A server connect event, used to verify that the connection is up and running
+ *
+ * @event Connection#connect
+ * @type {Connection}
+ */
+
+/**
+ * The server connection closed, all pool connections closed
+ *
+ * @event Connection#close
+ * @type {Connection}
+ */
+
+/**
+ * The server connection caused an error, all pool connections closed
+ *
+ * @event Connection#error
+ * @type {Connection}
+ */
+
+/**
+ * The server connection timed out, all pool connections closed
+ *
+ * @event Connection#timeout
+ * @type {Connection}
+ */
+
+/**
+ * The driver experienced an invalid message, all pool connections closed
+ *
+ * @event Connection#parseError
+ * @type {Connection}
+ */
+
+/**
+ * An event emitted each time the connection receives a parsed message from the wire
+ *
+ * @event Connection#message
+ * @type {Connection}
+ */
+
+module.exports = Connection;

node_modules/mongodb/lib/core/connection/logger.js

@@ -0,0 +1,251 @@
+'use strict';
+
+var f = require('util').format,
+  MongoError = require('../error').MongoError;
+
+// Filters for classes
+var classFilters = {};
+var filteredClasses = {};
+var level = null;
+// Save the process id
+var pid = process.pid;
+// current logger
+var currentLogger = null;
+
+/**
+ * @callback Logger~loggerCallback
+ * @param {string} msg message being logged
+ * @param {object} state an object containing more metadata about the logging message
+ */
+
+/**
+ * Creates a new Logger instance
+ * @class
+ * @param {string} className The Class name associated with the logging instance
+ * @param {object} [options=null] Optional settings.
+ * @param {Logger~loggerCallback} [options.logger=null] Custom logger function;
+ * @param {string} [options.loggerLevel=error] Override default global log level.
+ */
+var Logger = function(className, options) {
+  if (!(this instanceof Logger)) return new Logger(className, options);
+  options = options || {};
+
+  // Current reference
+  this.className = className;
+
+  // Current logger
+  if (options.logger) {
+    currentLogger = options.logger;
+  } else if (currentLogger == null) {
+    currentLogger = console.log;
+  }
+
+  // Set level of logging, default is error
+  if (options.loggerLevel) {
+    level = options.loggerLevel || 'error';
+  }
+
+  // Add all class names
+  if (filteredClasses[this.className] == null) classFilters[this.className] = true;
+};
+
+/**
+ * Log a message at the debug level
+ * @method
+ * @param {string} message The message to log
+ * @param {object} object additional meta data to log
+ * @return {null}
+ */
+Logger.prototype.debug = function(message, object) {
+  if (
+    this.isDebug() &&
+    ((Object.keys(filteredClasses).length > 0 && filteredClasses[this.className]) ||
+      (Object.keys(filteredClasses).length === 0 && classFilters[this.className]))
+  ) {
+    var dateTime = new Date().getTime();
+    var msg = f('[%s-%s:%s] %s %s', 'DEBUG', this.className, pid, dateTime, message);
+    var state = {
+      type: 'debug',
+      message: message,
+      className: this.className,
+      pid: pid,
+      date: dateTime
+    };
+    if (object) state.meta = object;
+    currentLogger(msg, state);
+  }
+};
+
+/**
+ * Log a message at the warn level
+ * @method
+ * @param {string} message The message to log
+ * @param {object} object additional meta data to log
+ * @return {null}
+ */
+(Logger.prototype.warn = function(message, object) {
+  if (
+    this.isWarn() &&
+    ((Object.keys(filteredClasses).length > 0 && filteredClasses[this.className]) ||
+      (Object.keys(filteredClasses).length === 0 && classFilters[this.className]))
+  ) {
+    var dateTime = new Date().getTime();
+    var msg = f('[%s-%s:%s] %s %s', 'WARN', this.className, pid, dateTime, message);
+    var state = {
+      type: 'warn',
+      message: message,
+      className: this.className,
+      pid: pid,
+      date: dateTime
+    };
+    if (object) state.meta = object;
+    currentLogger(msg, state);
+  }
+}),
+  /**
+   * Log a message at the info level
+   * @method
+   * @param {string} message The message to log
+   * @param {object} object additional meta data to log
+   * @return {null}
+   */
+  (Logger.prototype.info = function(message, object) {
+    if (
+      this.isInfo() &&
+      ((Object.keys(filteredClasses).length > 0 && filteredClasses[this.className]) ||
+        (Object.keys(filteredClasses).length === 0 && classFilters[this.className]))
+    ) {
+      var dateTime = new Date().getTime();
+      var msg = f('[%s-%s:%s] %s %s', 'INFO', this.className, pid, dateTime, message);
+      var state = {
+        type: 'info',
+        message: message,
+        className: this.className,
+        pid: pid,
+        date: dateTime
+      };
+      if (object) state.meta = object;
+      currentLogger(msg, state);
+    }
+  }),
+  /**
+   * Log a message at the error level
+   * @method
+   * @param {string} message The message to log
+   * @param {object} object additional meta data to log
+   * @return {null}
+   */
+  (Logger.prototype.error = function(message, object) {
+    if (
+      this.isError() &&
+      ((Object.keys(filteredClasses).length > 0 && filteredClasses[this.className]) ||
+        (Object.keys(filteredClasses).length === 0 && classFilters[this.className]))
+    ) {
+      var dateTime = new Date().getTime();
+      var msg = f('[%s-%s:%s] %s %s', 'ERROR', this.className, pid, dateTime, message);
+      var state = {
+        type: 'error',
+        message: message,
+        className: this.className,
+        pid: pid,
+        date: dateTime
+      };
+      if (object) state.meta = object;
+      currentLogger(msg, state);
+    }
+  }),
+  /**
+   * Is the logger set at info level
+   * @method
+   * @return {boolean}
+   */
+  (Logger.prototype.isInfo = function() {
+    return level === 'info' || level === 'debug';
+  }),
+  /**
+   * Is the logger set at error level
+   * @method
+   * @return {boolean}
+   */
+  (Logger.prototype.isError = function() {
+    return level === 'error' || level === 'info' || level === 'debug';
+  }),
+  /**
+   * Is the logger set at error level
+   * @method
+   * @return {boolean}
+   */
+  (Logger.prototype.isWarn = function() {
+    return level === 'error' || level === 'warn' || level === 'info' || level === 'debug';
+  }),
+  /**
+   * Is the logger set at debug level
+   * @method
+   * @return {boolean}
+   */
+  (Logger.prototype.isDebug = function() {
+    return level === 'debug';
+  });
+
+/**
+ * Resets the logger to default settings, error and no filtered classes
+ * @method
+ * @return {null}
+ */
+Logger.reset = function() {
+  level = 'error';
+  filteredClasses = {};
+};
+
+/**
+ * Get the current logger function
+ * @method
+ * @return {Logger~loggerCallback}
+ */
+Logger.currentLogger = function() {
+  return currentLogger;
+};
+
+/**
+ * Set the current logger function
+ * @method
+ * @param {Logger~loggerCallback} logger Logger function.
+ * @return {null}
+ */
+Logger.setCurrentLogger = function(logger) {
+  if (typeof logger !== 'function') throw new MongoError('current logger must be a function');
+  currentLogger = logger;
+};
+
+/**
+ * Set what classes to log.
+ * @method
+ * @param {string} type The type of filter (currently only class)
+ * @param {string[]} values The filters to apply
+ * @return {null}
+ */
+Logger.filter = function(type, values) {
+  if (type === 'class' && Array.isArray(values)) {
+    filteredClasses = {};
+
+    values.forEach(function(x) {
+      filteredClasses[x] = true;
+    });
+  }
+};
+
+/**
+ * Set the current log level
+ * @method
+ * @param {string} level Set current log level (debug, info, error)
+ * @return {null}
+ */
+Logger.setLevel = function(_level) {
+  if (_level !== 'info' && _level !== 'error' && _level !== 'debug' && _level !== 'warn') {
+    throw new Error(f('%s is an illegal logging level', _level));
+  }
+
+  level = _level;
+};
+
+module.exports = Logger;

node_modules/mongodb/lib/core/connection/msg.js

@@ -0,0 +1,222 @@
+'use strict';
+
+// Implementation of OP_MSG spec:
+// https://github.com/mongodb/specifications/blob/master/source/message/OP_MSG.rst
+//
+// struct Section {
+//   uint8 payloadType;
+//   union payload {
+//       document  document; // payloadType == 0
+//       struct sequence { // payloadType == 1
+//           int32      size;
+//           cstring    identifier;
+//           document*  documents;
+//       };
+//   };
+// };
+
+// struct OP_MSG {
+//   struct MsgHeader {
+//       int32  messageLength;
+//       int32  requestID;
+//       int32  responseTo;
+//       int32  opCode = 2013;
+//   };
+//   uint32      flagBits;
+//   Section+    sections;
+//   [uint32     checksum;]
+// };
+
+const Buffer = require('safe-buffer').Buffer;
+const opcodes = require('../wireprotocol/shared').opcodes;
+const databaseNamespace = require('../wireprotocol/shared').databaseNamespace;
+const ReadPreference = require('../topologies/read_preference');
+
+// Incrementing request id
+let _requestId = 0;
+
+// Msg Flags
+const OPTS_CHECKSUM_PRESENT = 1;
+const OPTS_MORE_TO_COME = 2;
+const OPTS_EXHAUST_ALLOWED = 1 << 16;
+
+class Msg {
+  constructor(bson, ns, command, options) {
+    // Basic options needed to be passed in
+    if (command == null) throw new Error('query must be specified for query');
+
+    // Basic options
+    this.bson = bson;
+    this.ns = ns;
+    this.command = command;
+    this.command.$db = databaseNamespace(ns);
+
+    if (options.readPreference && options.readPreference.mode !== ReadPreference.PRIMARY) {
+      this.command.$readPreference = options.readPreference.toJSON();
+    }
+
+    // Ensure empty options
+    this.options = options || {};
+
+    // Additional options
+    this.requestId = options.requestId ? options.requestId : Msg.getRequestId();
+
+    // Serialization option
+    this.serializeFunctions =
+      typeof options.serializeFunctions === 'boolean' ? options.serializeFunctions : false;
+    this.ignoreUndefined =
+      typeof options.ignoreUndefined === 'boolean' ? options.ignoreUndefined : false;
+    this.checkKeys = typeof options.checkKeys === 'boolean' ? options.checkKeys : false;
+    this.maxBsonSize = options.maxBsonSize || 1024 * 1024 * 16;
+
+    // flags
+    this.checksumPresent = false;
+    this.moreToCome = options.moreToCome || false;
+    this.exhaustAllowed =
+      typeof options.exhaustAllowed === 'boolean' ? options.exhaustAllowed : false;
+  }
+
+  toBin() {
+    const buffers = [];
+    let flags = 0;
+
+    if (this.checksumPresent) {
+      flags |= OPTS_CHECKSUM_PRESENT;
+    }
+
+    if (this.moreToCome) {
+      flags |= OPTS_MORE_TO_COME;
+    }
+
+    if (this.exhaustAllowed) {
+      flags |= OPTS_EXHAUST_ALLOWED;
+    }
+
+    const header = Buffer.alloc(
+      4 * 4 + // Header
+        4 // Flags
+    );
+
+    buffers.push(header);
+
+    let totalLength = header.length;
+    const command = this.command;
+    totalLength += this.makeDocumentSegment(buffers, command);
+
+    header.writeInt32LE(totalLength, 0); // messageLength
+    header.writeInt32LE(this.requestId, 4); // requestID
+    header.writeInt32LE(0, 8); // responseTo
+    header.writeInt32LE(opcodes.OP_MSG, 12); // opCode
+    header.writeUInt32LE(flags, 16); // flags
+    return buffers;
+  }
+
+  makeDocumentSegment(buffers, document) {
+    const payloadTypeBuffer = Buffer.alloc(1);
+    payloadTypeBuffer[0] = 0;
+
+    const documentBuffer = this.serializeBson(document);
+    buffers.push(payloadTypeBuffer);
+    buffers.push(documentBuffer);
+
+    return payloadTypeBuffer.length + documentBuffer.length;
+  }
+
+  serializeBson(document) {
+    return this.bson.serialize(document, {
+      checkKeys: this.checkKeys,
+      serializeFunctions: this.serializeFunctions,
+      ignoreUndefined: this.ignoreUndefined
+    });
+  }
+}
+
+Msg.getRequestId = function() {
+  _requestId = (_requestId + 1) & 0x7fffffff;
+  return _requestId;
+};
+
+class BinMsg {
+  constructor(bson, message, msgHeader, msgBody, opts) {
+    opts = opts || { promoteLongs: true, promoteValues: true, promoteBuffers: false };
+    this.parsed = false;
+    this.raw = message;
+    this.data = msgBody;
+    this.bson = bson;
+    this.opts = opts;
+
+    // Read the message header
+    this.length = msgHeader.length;
+    this.requestId = msgHeader.requestId;
+    this.responseTo = msgHeader.responseTo;
+    this.opCode = msgHeader.opCode;
+    this.fromCompressed = msgHeader.fromCompressed;
+
+    // Read response flags
+    this.responseFlags = msgBody.readInt32LE(0);
+    this.checksumPresent = (this.responseFlags & OPTS_CHECKSUM_PRESENT) !== 0;
+    this.moreToCome = (this.responseFlags & OPTS_MORE_TO_COME) !== 0;
+    this.exhaustAllowed = (this.responseFlags & OPTS_EXHAUST_ALLOWED) !== 0;
+    this.promoteLongs = typeof opts.promoteLongs === 'boolean' ? opts.promoteLongs : true;
+    this.promoteValues = typeof opts.promoteValues === 'boolean' ? opts.promoteValues : true;
+    this.promoteBuffers = typeof opts.promoteBuffers === 'boolean' ? opts.promoteBuffers : false;
+
+    this.documents = [];
+  }
+
+  isParsed() {
+    return this.parsed;
+  }
+
+  parse(options) {
+    // Don't parse again if not needed
+    if (this.parsed) return;
+    options = options || {};
+
+    this.index = 4;
+    // Allow the return of raw documents instead of parsing
+    const raw = options.raw || false;
+    const documentsReturnedIn = options.documentsReturnedIn || null;
+    const promoteLongs =
+      typeof options.promoteLongs === 'boolean' ? options.promoteLongs : this.opts.promoteLongs;
+    const promoteValues =
+      typeof options.promoteValues === 'boolean' ? options.promoteValues : this.opts.promoteValues;
+    const promoteBuffers =
+      typeof options.promoteBuffers === 'boolean'
+        ? options.promoteBuffers
+        : this.opts.promoteBuffers;
+
+    // Set up the options
+    const _options = {
+      promoteLongs: promoteLongs,
+      promoteValues: promoteValues,
+      promoteBuffers: promoteBuffers
+    };
+
+    while (this.index < this.data.length) {
+      const payloadType = this.data.readUInt8(this.index++);
+      if (payloadType === 1) {
+        console.error('TYPE 1');
+      } else if (payloadType === 0) {
+        const bsonSize = this.data.readUInt32LE(this.index);
+        const bin = this.data.slice(this.index, this.index + bsonSize);
+        this.documents.push(raw ? bin : this.bson.deserialize(bin, _options));
+
+        this.index += bsonSize;
+      }
+    }
+
+    if (this.documents.length === 1 && documentsReturnedIn != null && raw) {
+      const fieldsAsRaw = {};
+      fieldsAsRaw[documentsReturnedIn] = true;
+      _options.fieldsAsRaw = fieldsAsRaw;
+
+      const doc = this.bson.deserialize(this.documents[0], _options);
+      this.documents = [doc];
+    }
+
+    this.parsed = true;
+  }
+}
+
+module.exports = { Msg, BinMsg };

node_modules/mongodb/lib/core/connection/utils.js

@@ -0,0 +1,57 @@
+'use strict';
+
+const require_optional = require('require_optional');
+
+function debugOptions(debugFields, options) {
+  var finaloptions = {};
+  debugFields.forEach(function(n) {
+    finaloptions[n] = options[n];
+  });
+
+  return finaloptions;
+}
+
+function retrieveBSON() {
+  var BSON = require('bson');
+  BSON.native = false;
+
+  try {
+    var optionalBSON = require_optional('bson-ext');
+    if (optionalBSON) {
+      optionalBSON.native = true;
+      return optionalBSON;
+    }
+  } catch (err) {} // eslint-disable-line
+
+  return BSON;
+}
+
+// Throw an error if an attempt to use Snappy is made when Snappy is not installed
+function noSnappyWarning() {
+  throw new Error(
+    'Attempted to use Snappy compression, but Snappy is not installed. Install or disable Snappy compression and try again.'
+  );
+}
+
+// Facilitate loading Snappy optionally
+function retrieveSnappy() {
+  var snappy = null;
+  try {
+    snappy = require_optional('snappy');
+  } catch (error) {} // eslint-disable-line
+  if (!snappy) {
+    snappy = {
+      compress: noSnappyWarning,
+      uncompress: noSnappyWarning,
+      compressSync: noSnappyWarning,
+      uncompressSync: noSnappyWarning
+    };
+  }
+  return snappy;
+}
+
+module.exports = {
+  debugOptions,
+  retrieveBSON,
+  retrieveSnappy
+};